Articles de revues : « Stratigraphic Geological mapping »

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Seggie, R. J., S. C. Lang, N. M. Marshall, C. J. Cubitt, D. Alsop, R. Kirk et S. Twartz. « INTEGRATED MULTI-DISCIPLINARY ANALYSIS OF THE RANKIN TREND GAS RESERVOIRS NORTH WEST SHELF, AUSTRALIA ». APPEA Journal 47, n^o 1 (2007) : 55. http://dx.doi.org/10.1071/aj06003.

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An integrated geological study of the Rankin Trend of the North West Shelf, Australia, was undertaken to underpin the ongoing development of the giant gas fields it contains. The study applied an improved understanding ofthe regional stratigraphy in conjunction with interpretation of the regional-scale Demeter 3D seismic survey and focussed on existing fields, undeveloped discoveries, and exploration prospects. The study included a redescription of 1,500 m of core, a new facies-based petrological analysis, a revision of the well-based stratigraphy and palaeogeographic mapping, and a seismic stratigraphic analysis. Reservoir production and hydrodynamic data were also integrated. The stratigraphic framework was improved by implementing a broad range of depositional and facies analogues and a system-wide sequence stratigraphic approach to understanding lateral and vertical stacking patterns of the reservoir succession. Visualisation and modelling technologies were also employed to more adequately describe genetic reservoir packages.Specific outcomes include: improved correlation of reservoir sequences, application of appropriate subsurface depositional analogues to field descriptions, updated palaeogeographic maps and recognition of palaeosols as stratigraphic marker horizons—resulting in a more consistent regional interpretation framework. This forms the basis for seismic stratigraphic interpretation away from well control.The new regional geological model has enabled the linkage of exploration, development and production understanding across the North West Shelf assets as well as management of geological uncertainties.

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Kombrink, H., J. C. Doornenbal, E. J. T. Duin, M. den Dulk, J. H. ten Veen et N. Witmans. « New insights into the geological structure of the Netherlands ; results of a detailed mapping project ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 91, n^o 4 (décembre 2012) : 419–46. http://dx.doi.org/10.1017/s0016774600000329.

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AbstractA five years geological mapping project, in which the Netherlands Continental Shelf has been re-examined using all publicly available data, resulted in an important update of the existing dataset. The stratigraphy of over 400 wells has been re-interpreted. New depth and thickness grids, based mainly on the interpretation of 3D seismic data have been produced for the most important stratigraphic intervals from Permian Upper Rotliegend to Neogene. New reservoir grids describe the top, base and thickness of 30 (potential) reservoir units in the area. In addition, the uncertainty related to interpretation and further processing of the data has been assessed. This resulted in maps displaying the standard deviation for the depth of the main stratigraphic intervals. Based on these results and the data already available for the onshore area, an updated structural element map was made for the Netherlands.

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Birkenmajer, Krzysztof. « Polish Geological Research in Svalbard ». Earth Sciences History 11, n^o 2 (1 janvier 1992) : 81–87. http://dx.doi.org/10.17704/eshi.11.2.n2747185001nv261.

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The Polish geological investigations started in the Svalbard archipelago in 1934. The most diversified stratigraphic, tectonic, sedimentological and palacontological work, along with detailed geological mapping, was carried out in the Hornsund area, south Spitsbergen, between 1957 and 1960, in connection with the Illrd International Geophysical Year and its prolongation (International Geophysical Co-operation). Between 1962 and 1970, some Polish geologists worked in Spitsbergen for the Norwegian Polar Institute. From 1974 onwards, the Polish geological investigations extended from southern to central and eastern Spitsbergen. In south Spitsbergen, at Hornsund, they are based at the Polish Scientific Station built already in 1957, and renovated in 1978. The paper presents a review of mainly pre-Quaternary (Proterozoic through Tertiary) geological, structuraltectonic, petrological, stratigraphic, palaeontologiesl and sedimentologtcal problems of Svalbard elaborated by the Polish geologists.

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KROCHAK, Maryna. « МEMORIES ON THE FIELD COURSE IN GEOLOGICAL MAPPING ». Ukrainian Geologist, n^o 1-2(44-45) (30 juin 2021) : 158–60. http://dx.doi.org/10.53087/ug.2021.1-2(44-45).238970.

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This article is a memory of the field course in geological mapping. It was a part of studying process of the author while her education at the Geology & Geophysics Department, Novosibirsk University. The practice took place in the 80s of the last century in the steppe region of the Khakassia Autonomous Region (Krasnoyarsk Territory, Russia) at the university’s geological training camp. The article features a technique of creating a geological map of the site. Geological strata were distinguished by lithological features. However, the instructors did not indicate the real geological age of the deposits to the students because it was believed that such information is unnecessary for them. The main task of students was to master the methods of geological mapping of an unknown territory. Students covered the site with routes along the cross of the strike of sediments. Students had to recognize these sediments, determine the area of their distribution, divide them into stratigraphic horizons and give them their own names. Then students marked the boundaries of the rock layers at outcrops and the elements of their occurrence on the topographic base. This original teaching method gave a positive result. Students have developed a geological map of the training site where certain stratigraphic horizons were shown with real bedding elements. This approach contributed to the independent creative work of students. Students felt themselves like pioneer geologists who came to this territory for the first time, conducted geological mapping and gave names to geological strata that are exposed. In addition, this method excluded the possibility of cheating and copying the existing real geological map. The article presents memories of the young nineteen-year-old student’s perception of the features of field geology, expeditionary life and collective work. With a certain degree of self-irony the author brings his thoughts, feelings and impressions of nature. The experience gained during this field practice has become the basis of the author’s professional skills and now helps us in educational process.

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Matano, Fabio, Silvio Di Nocera, Sara Criniti et Salvatore Critelli. « Geology of the Epicentral Area of the November 23, 1980 Earthquake (Irpinia, Italy) : New Stratigraphical, Structural and Petrological Constrains ». Geosciences 10, n^o 6 (25 juin 2020) : 247. http://dx.doi.org/10.3390/geosciences10060247.

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The geology of the epicentral area of the 1980 earthquake (Irpinia-Lucania, Italy) is described with new stratigraphic, petrographic and structural data. Subsurface geological data have been collected during the studies for the excavation works of the Pavoncelli bis hydraulic tunnel, developing between Caposele and Conza della Campania in an area that was highly damaged during 1980 earthquake. Our approach includes geological, stratigraphic, structural studies, and petrological analyses of rock samples collected along the tunnel profile and in outcropping sections. Stratigraphic studies and detailed geological and structural mapping were carried out in about 200 km2 wide area. The main units cropping out have been studied and correlated in order to document the effects of tectonic changes during the orogenic evolution on the foreland basin systems and the sandstone detrital modes in this sector of the southern Apennines. The multi-disciplinary and updated datasets have allowed getting new insights on the tectono-stratigraphic evolution and stratigraphic architecture of the southern Apennines foreland basin system and on the structural and stratigraphic relations of Apennines tectonic units and timing of their kinematic evolution. They also allowed to better understand the relationships between internal and external basin units within the Apennine thrust belt and its tectonic evolution.

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Tracey, Joshua. « Surveying the Nomenclature of Geologic Time ». Earth Sciences History 8, n^o 2 (1 janvier 1989) : 183–89. http://dx.doi.org/10.17704/eshi.8.2.cv506tk65l518760.

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Publication in 1976 of the International Stratigraphic Guide climaxed a movement toward unification of nomenclature begun a century earlier when an American committee formed to promote an international meeting of geologists. American stratigraphic practice during the remainder of the 19th Century developed chiefly through the needs of the United States Geological Survey for uniform standards in geologic nomenclature and cartography. The requirement for maps which were usable by the intelligent layman for practical purposes led Directors King and Powell to emphasize the mapping of lithology, rather than time units delineated faunally. This approach was not universally accepted and led to bitter dispute. H. S. Williams and C. D. Walcott deserve credit for clarifying the distinction between terms for time and terms for rocks. Under Director Walcott, the 1890 codification of Powell was modified and formalized into the 1904 "Rules" of the U.S. Geological Survey. A major distinction was the placing in separate sections those rules concerned with lithologic units and those concerned with time and correlation. This dual classification, fundamental to all United States and North American stratigraphic codes during this century, has become a guiding principal in the international efforts at standardization of usage.

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Surlyk, F. « Tectonostratigraphy of North Greenland ». Bulletin Grønlands Geologiske Undersøgelse 160 (1 janvier 1991) : 25–47. http://dx.doi.org/10.34194/bullggu.v160.6712.

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A coherent tectonic and stratigraphic picture of the geological evolution of North Greenland has emerged after a decade of systematic mapping and topical studies by the Geological Survey of Greenland (GGU) in cooperation with groups from the University of Copenhagen and various non-Danish institutions. These studies represent the culmination of a long exploration history, with field work often carried out under harsh conditions.

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Shubin, Mikhail. « Сartographic Provision of Monitoring of Engineering-Geological Processes on the Basis of GIS-Technologies ». Natural Systems and Resources, n^o 4 (décembre 2018) : 64–69. http://dx.doi.org/10.15688/nsr.jvolsu.2018.4.8.

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Mapping information is needed when using geo-information technologies to develop a system of monitoring geological processes. The thematic basis of the engineering-geological map is a data Bank for assessing the state of the geological environment. The sources of the digital cartographic basis are remote sensing data and field survey materials. The data is included in the contents of the MapInfo working set. Engineering-geologic map consists of two thematic layers. The first layer - stratigraphic genetic complexes of surface deposits, their composition and physical and mechanical properties. The second layer is a characteristic of exogenous processes, including a description of the types, prevalence (scale) and intensity of manifestation separately for each group of processes: landslide, erosion, Aeolian, suffusion-karst, waterlogging and flooding. As an example, the map of soil density in MapInfo for the pipeline section is shown.

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Wang, Chengbin, Xinqing Wang et Jianguo Chen. « Digital Geological Mapping to Facilitate Field Data Collection, Integration, and Map Production in Zhoukoudian, China ». Applied Sciences 11, n^o 11 (29 mai 2021) : 5041. http://dx.doi.org/10.3390/app11115041.

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The development of innovative information technologies has improved the geological mapping process through the use of smart and portable equipment to collect field data, build a geological database and produce geological maps. This revolution has also brought great influence and challenges to practical training in field geology. In this paper, we present our workflow and application of the Digital Geological Survey System (DGSS) during field geology training for undergraduates in Zhoukoudian. The DGSS employs a Point-Routing-Boundary (PRB) model to reform the methods of geological section survey and geological mapping in terms of data collection and map-making and provides a pipelined solution from field data collection to map-making. The experiences of data collection, geological mapping, cross-section survey, and production of stratigraphic histograms and cross-section maps prove that DGSS can save time and reduce labor intensity for undergraduates during learning field geology. Based on the field practice of undergraduates in Zhoukoudian, the influence of the DGSS in promoting field geological teaching and the students’ feedbacks to DGSS are discussed. Overall, the DGM system is more popular than the conventional notebook and toolbox. The experience in Zhoukoudian proves that digital devices are efficient and useful for geological practical training of field geology for undergraduates.

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Paudyal, KR, LB Adhikari, N. Maharjan et LP Paudel. « Geological setting and lithostratigraphy of Bandipur-Gondrang area of Lesser Himalaya, central Nepal ». Bulletin of the Department of Geology 15 (21 janvier 2013) : 49–62. http://dx.doi.org/10.3126/bdg.v15i0.7417.

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Detailed geological mapping was carried out in the Bandipur-Gondrang area of Tanahun district to clarify the geological set up and stratigraphy of the area. Wherever possible, geological mapping is based on stratigraphic units proposed by Stocklin and Bhattarai (1977) in central Nepal and the present mapping is the west ward continuation from Mugling-Banspani area (Paudyal and Paudel, 2011). The study area comprises low grade metasedimentary rocks of Nawakot Complex. The rock succession of the area are divided into six formations as the Kunchha Formation, the Fagfog Quartzite, the Dandagaon Phyllite, the Nourpul Formation with four members, the Dhading Dolomite and the Benighat Slates in stratigraphic upwards. The former four formations belong to Upper Nawakot Group and the remaining one belongs to the Lower Nawakot Group of Nawakot Complex (Stöcklin and Bhattarai, 1977). Based on lithology, the Nourpul Formation is divided into the Purebensi Quartzite, the Amdanda Phyllite, the Labdi Khola Member and the Bandipur Slate from bottom to top respectively. The Purebensi Quartzite is lithologically distinct in the field; the Labdi Khola Member is significant with copper and iron mineralization in the area, and the Bandipur Slate is also significant with roofing quality slate, however, the Amdanda Phyllite is mapped as an intervening member between significant lithologies. The rocks of the present study area consist of several sedimentary structures like mud cracks, ripple marks, graded bedding and cross and parallel laminations. A broad Ghumaune- Gondran Synclinorium is mapped in the area. In addition to this, several anticlines and synclines are also mapped in the study area. Jalbhanjyang Thrust has brought the older metasedimentary rocks of the Nawakot Complex over the younger rocks of the same Complex. Some corrections are recommended over the distribution of previously shown lithological units by Stocklin and Bhattarai (1977) around the Ghumaune-Bhut Khola section. DOI: http://dx.doi.org/10.3126/bdg.v15i0.7417 Bulletin of the Department of Geology, Vol. 15, 2012, pp. 49-62

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Perrella Júnior, Pascoal, Alexandre Uhlein, Gabriel Jube Uhlein, Alcides Nobrega Sial, Antônio Carlos Pedrosa-Soares et Otávio Nunes Borges de Lima. « Facies analysis, sequence stratigraphy and chemostratigraphy of the Sete Lagoas Formation (Bambui Group), northern Minas Gerais State, Brazil : evidence of a cap carbonate deposited on the Januária basement high ». Brazilian Journal of Geology 47, n^o 1 (janvier 2017) : 59–77. http://dx.doi.org/10.1590/2317-4889201720160112.

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ABSTRACT: Sedimentary rocks of the Sete Lagoas Formation, exposed in the left margin of the São Francisco river (Minas Gerais State, Brazil), were deposited on the Januária-Itacarambi basement high. They show both lateral and vertical rock stacking along continuous outcrops, allowing us to carry out detailed facies analysis and sequence stratigraphy studies. Our studies also integrate data from geological mapping, macro and microscopic petrography and high-resolution C and O isotope analysis. Eight facies and four facies associations make up a sequence composed by a transgressive tract in the base, and a high stand tract in the upper portion, separated by a maximum flooding surface. The high stand tract shows a progradation stacking from the basement high apex towards progressively deeper basement areas. This stratigraphic framework, associated with others stratigraphic and isotopic features, indicates that the now exposed Januária basement high also represents a paleo-high during the sedimentation event. Aragonite pseudomorphs and dolomites coupled with δ13C values of -5‰ characterize the basal carbonate of the transgressive tract as a cap carbonate. Records of the Cloudina fossil, recognized in the high stand tract, indicate a Late Ediacaran age for the upper portion of the studied stratigraphic sequence.

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BOULVAIN, Frédéric, Isabelle BELANGER, Dominique DELSATE, Pierre GHYSEL, Pascal GODEFROIT, Martin LALOUX, Roger MONTEYNE et Marc ROCHE. « Triassic and Jurassic lithostratigraphic units (Belgian Lorraine) ». Geologica Belgica 4, n^o 1-2 (15 avril 2002) : 113–19. http://dx.doi.org/10.20341/gb.2014.048.

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A multidisciplinary study of some extensively cored boreholes together with the new 1/25,000 geological mapping of Wallonia led us to propose a new lithostratigraphic canvas for Belgian Lorraine. This area is located on the NE border of the Paris Basin, south of the Ardennes; the studied stratigraphic interval covers the Late Triassic to the Bajocian.

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Olaleye, O. K., P. A. Enikanselu et M. A. Ayuk. « Use of spectral decomposition technique for mapping geologic features of ‘Reigh’ field, Onshore Niger Delta ». Nigeria Journal of Pure and Applied Physics 10, n^o 1 (6 mai 2021) : 1–7. http://dx.doi.org/10.4314/njpap.v10i1.1.

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Spectral Decomposition Technique based on Short-Window Discrete Fourier Transform (SWDFT) was applied to threedimensional (3D) seismic data obtained from ‘Reigh’ field, onshore Niger Delta with a view to enhancing stratigraphic interpretation for geological features which are beyond seismic resolution. Two sands units from the study area were studied to produce spectrally decomposedsurfaces. The result of the study revealed thin bed layer at the centre of the field on sand unit ‘A’. Sand-filled meandering channel wasdetected and highlighted in the northern part of sand unit ‘B’ based on Red-Green-Blue frequency modulation of spectral decomposition. The study has enhanced geologic understanding of the field by improving thin bed resolution, highlighting geologic features and displaying bed thickness variation of studied sand units in the study area. Keywords: geologic features, Niger Delta, seismic data, spectral decomposition

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Fuller, J. « Stratigraphic Stand-Off at the 49th Parallel ». Earth Sciences History 24, n^o 2 (1 janvier 2005) : 247–64. http://dx.doi.org/10.17704/eshi.24.2.w220364922xw6906.

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The 49th Parallel divides the western Prairies between Canada and the United States, crossing the central part of the Williston basin and marking the International boundary that separates Saskatchewan from the States of Montana and North Dakota. Discoveries of oil in this area during the 1950s triggered widespread geological activity, and revealed significant differences of stratigraphical understanding on each side of the border. Problems seemed to arise from contrasts between ‘American' and ‘English' interpretations of stratigraphical method, particularly for the oil-producing zones of the Mississippian. This study analyzes the differing points of view, and presents historical reasons for them. Difficulties with stratigraphical method and nomenclature in the 1950s were quite real, becoming the subject in 1959 of a special AAPG-SEPM conference at Dallas. Had the delegates attending that meeting (including the present author) possessed a little more history, they would have known that an ‘American' or mineral-focused view of stratigraphy had originated in a German hard-rock mining terrane, principally through the teaching of Abraham Werner. From there, during the first years of the 19th century, it traveled via Scotland to the State of New York, where, from Amos Eaton's Rensselaer School at Troy, it spread to most of the newly-formed State geological surveys. Some years later, on the other hand, an ‘English' or ‘stratum-focused' view of stratified formations migrated across the Atlantic from the pastoral landscapes and gently inclined rock-formations of southern England, where mapping had tended to discount their mineral content in favor of their observable order and continuity.

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Miall, Andrew D. « Logan Medallist 3. Making Stratigraphy Respectable : From Stamp Collecting to Astronomical Calibration ». Geoscience Canada 42, n^o 3 (29 juillet 2015) : 271. http://dx.doi.org/10.12789/geocanj.2015.42.072.

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The modern science of stratigraphy is founded on a nineteenth-century empirical base – the lithostratigraphy and biostratigraphy of basin-fill successions. This stratigraphic record comprises the most complete data set available for reconstructing the tectonic and climatic history of Earth. However, it has taken two hundred years of evolution of concepts and methods for the science to evolve from what Ernest Rutherford scornfully termed “stamp collecting” to a modern dynamic science characterized by an array of refined methods for documenting geological rates and processes. Major developments in the evolution of the science of stratigraphy include the growth of an ever-more precise geological time scale, the birth of sedimentology and basin-analysis methods, the influence of plate tectonics and, most importantly, the development, since the late 1970s, of the concepts of sequence stratigraphy. Refinements in these concepts have required the integration of all pre-existing data and methods into a modern, multidisciplinary approach, as exemplified by the current drive to apply the retrodicted history of Earth’s orbital behaviour to the construction of a high-precision ‘astrochronological’ time scale back to at least the Mesozoic record. At its core, stratigraphy, like much of geology, is a field-based science. The field context of a stratigraphic sample or succession remains the most important starting point for any advanced mapping, analytical or modeling work.RÉSUMÉLa science moderne de la stratigraphie repose sur une base empirique du XIXe siècle, soit la lithostratigraphie et la biostratigraphie de successions de remplissage de bassins sédimentaires. Cette archive stratigraphique est constituée de la base de données la plus complète permettant de reconstituer l’histoire tectonique et climatique de la Terre. Cela dit, il aura fallu deux cents ans d’évolution des concepts et des méthodes pour que cette activité passe de l’état de « timbromanie », comme disait dédaigneusement Ernest Rutherford, à l’état de science moderne dynamique caractérisée par sa panoplie de méthodes permettant de documenter les rythmes et processus géologiques. Les principaux développements de l’évolution de la science de la stratigraphie proviennent de l’élaboration d’une échelle géologique toujours plus précise, l’avènement de la sédimentologie et des méthodes d’analyse des bassins, de l’influence de la tectonique des plaques et, surtout du développement depuis la fin des années 1970, des concepts de stratigraphie séquentielle. Des raffinements dans ces concepts ont nécessité l'intégration de toutes les données et méthodes existantes dans une approche moderne, multidisciplinaire, comme le montre ce mouvement actuel qui entend utiliser la reconstitution de l’histoire du comportement orbital de la Terre pour l’élaboration d’une échelle temporelle « astrochronologique » de haute précision, remontant jusqu’au Mésozoïque au moins. Comme pour la géologie, la stratigraphie est une science de terrain. Le contexte de terrain d’un échantillon stratigraphique ou d’une succession demeure le point de départ le plus important, pour tout travail sérieux de cartographie, d’analyse ou de modélisation.

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Dzikunoo, Elikplim Abla, Giulio Vignoli, Flemming Jørgensen, Sandow Mark Yidana et Bruce Banoeng-Yakubo. « New regional stratigraphic insights from a 3D geological model of the Nasia sub-basin, Ghana, developed for hydrogeological purposes and based on reprocessed B-field data originally collected for mineral exploration ». Solid Earth 11, n^o 2 (17 mars 2020) : 349–61. http://dx.doi.org/10.5194/se-11-349-2020.

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Abstract. Reprocessing of regional-scale airborne electromagnetic data is used to build a 3D geological model of the Nasia sub-basin, northern Ghana. The resulting 3D geological model consistently integrates all the prior pieces of information brought by electromagnetic data, lithologic logs, ground-based geophysical surveys, and geological knowledge of the terrain. The geo-modeling process is aimed at defining the lithostratigraphy of the area, chiefly to improve the stratigraphic definition of the area, and for hydrogeological purposes. The airborne electromagnetic measurements, consisting of GEOTEM B-field data, were originally collected for mineral exploration purposes. Thus, those B-field data had to be (re)processed and properly inverted as the original survey and data handling were designed for the detection of potential mineral targets and not for detailed geological mapping. These new geophysical inversion results, compared with the original conductivity–depth images, provided a significantly different picture of the subsurface. The new geophysical model led to new interpretations of the geological settings and to the construction of a comprehensive 3D geo-model of the basin. In this respect, the evidence of a hitherto unexposed system of paleovalleys could be inferred from the airborne data. The stratigraphic position of these paleovalleys suggests a distinctly different glaciation history from the known Marinoan events, commonly associated with the Kodjari formation of the Voltaian sedimentary basin. Indeed, the presence of the paleovalleys within the Panabako may be correlated with mountain glaciation within the Sturtian age, though no unequivocal glaciogenic strata have yet been identified. Pre-Marinoan glaciation is recorded in rocks of the Wassangara group of the Taoudéni Basin. The combination of the Marinoan and, possibly, Sturtian glaciation episodes, both of the Cryogenian period, can be an indication of a Neoproterozoic Snowball Earth. Hence, the occurrence of those geological features not only has important socioeconomic consequences – as the paleovalleys can act as reservoirs for groundwater – but also from a scientific point of view, they could be extremely relevant as their presence would require a revision of the present stratigraphy of the area.

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ROBERTS, MICHAEL B. « I coloured a map : Darwin's attempts at geological mapping in 1831 ». Archives of Natural History 27, n^o 1 (février 2000) : 69–79. http://dx.doi.org/10.3366/anh.2000.27.1.69.

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In his autobiography describing his geology of 1831 Darwin wrote, “on my return to Shropshire I coloured a map of parts around Shrewsbury.” There are four extant maps in the Cambridge University Library, which fit this description. Two, at a scale of ⅞ inch to 1 mile, are of Anglesey and Llanymynech and are hand-drawn copies of Evan's map of North Wales, and are without geological annotation. The other two of Shrewsbury and Kinnerley have a scale of 1 inch to 1 mile and are copied from Baugh's Map of Shropshire (1808). These contain orange shading to the west of Shrewsbury indicating New Red Sandstone, but make no allowance for drift. The Shrewsbury map includes some attempted stratigraphic boundaries and marks four sites; A, B, C and D. These maps demonstrate Darwin's grasp of geology before his Welsh tour with Sedgwick in August 1831. They show his realisation of the need of a topographic base map, an acquaintance of the conventions of geological mapping in shading and the marking of boundaries. These maps form an early part of Darwin's considerable geological activity in the summer of 1831.

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Robaina, Luis Eduardo de Souza, Edgardo Ramos Medeiros et Carlos Alberto da Fonseca Pires. « Contribuição ao conhecimento geológico da Região Metropolitana de Porto Alegre, municípios de Novo Hamburgo, São Leopoldo e Campo Bom ». Ciência e Natura 18, n^o 18 (9 décembre 1996) : 183. http://dx.doi.org/10.5902/2179460x26710.

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This paper deals with geological mapping of the metropolitan region of São Leopoldo, Novo Hamburgo and Campo Bom cities. Through the geological mapping it was possible to recognize Permian and Triassic sediments and vulcanic rocks from the Parana Basin.The litological, textural and structural characteristics of sedimentary sequences were focused in order to such as the geomorphological aspects the separation and piling up the stratigraphic units. It was possible to identify the minerology of the most fine sediments with the use os diphatometry X. rays Quartz and feldspar were identif with ilite in the fine sediments and kaolinite in the sandy parto.The depositional conditions as well as relations contact between the sequences were also discussed. The transitions leve of the sedimentary part to the vulcanic part, happens at about 100m of altitude.The recents sedimentary sequences are unconsolidate clay and sandy sediments.

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Maevskaya, Anna, Nikolay Sheshko, Natalia Shpendik et Maksim Bogdasarov. « Structural geological mapping of the Cenozoic sediments of the Brest region using GIS technologies ». E3S Web of Conferences 212 (2020) : 01010. http://dx.doi.org/10.1051/e3sconf/202021201010.

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Cenozoic sediments of the territory of the Brest region is the object of research in this work. The aim of this work is to detail the structure of the Cenozoic stratigraphic deposits by creating a set of structural geological maps. The process of creating maps included several sequential stages implemented using the ArcGIS 10.5 software product. In general, a set of maps for each period of the Cenozoic era was made according to the implemented method. As a result of mapping, the features of the geological structure of the Cenozoic sediments were detailed (based on the use of the most complete materials on the drilling exploration of the territory during the construction). The use of geoinformation systems in the process of building will allow for quick updating of cartographic materials in the future.

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Gillespie, Martin R., et A. Graham Leslie. « BRUCS : a new system for classifying and naming mappable rock units ». Journal of the Geological Society 178, n^o 4 (10 février 2021) : jgs2020–212. http://dx.doi.org/10.1144/jgs2020-212.

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A new scheme is introduced for classifying and naming mappable rock bodies that lack primary stratification. In recognition of their distinctive geological characteristics, these ‘nonstratiform’ bodies are defined and classified according to their 3D form, spatial distribution and genetic relationships, in two hierarchical (parent–child) chains: one for intrusions and one for tectonometamorphic units. Geologically complex units, encompassing bodies of different genetic classes, are classified in a third chain reserved specifically for ‘mixed-class’ units. The new classification scheme is offered as an alternative to existing recommendations in the International Stratigraphic Guide and North American Stratigraphic Code, in which nonstratiform bodies are recognized and defined primarily by their lithological character. BRUCS (the BGS Rock Unit Classification System) combines the three new parent–child chains for nonstratiform units with the well-established chain for stratiform units (bed–member–formation–group–supergroup) to create a flexible, practical and effective solution for classifying and naming all mappable rock bodies. The taxonomic rigour of BRUCS means that the considerable capabilities of modern digital systems for managing and communicating mapping data can be exploited fully.

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Tognon, Gloria, Riccardo Pozzobon, Matteo Massironi et Sabrina Ferrari. « Geologic Mapping and Age Determinations of Tsiolkovskiy Crater ». Remote Sensing 13, n^o 18 (10 septembre 2021) : 3619. http://dx.doi.org/10.3390/rs13183619.

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Tsiolkovskiy is a ~200 km diameter crater presenting one of the few mare deposits of the lunar far side. In this work, we perform a geological study of the crater by means of morpho-stratigraphic and color-based spectral mappings, and a detailed crater counting age determination. The work aims at characterizing the surface morphology and compositional variation observed from orbital data including the Lunar Reconnaissance Orbiter Wide Angle Camera and Clementine UVVIS Warped Color Ratio mosaics, and attempts a reconstruction of the evolutionary history of the Tsiolkovskiy crater through both relative and absolute model age determinations. The results show a clear correlation between the geologic and spectral units and an asymmetric distribution of these units reflecting the oblique impact origin of the crater. Crater counts performed using the spectral units identified on the smooth crater floor returned distinct age ranges, suggesting the occurrence of at least three different igneous events, generating units characterized by particular compositions and/or degree of maturity. This work demonstrates the scientific value of Tsiolkovskiy crater for a better understanding of the volcanic evolution of the Moon and, in particular, of its far side.

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Raeuchle, Sandra K., William A. Ambrose, M. Saleem Akhter, Jhonny Casas, Lourdes Salamanca, Pedro Muñoz et Alfredo Leon. « Integrated reservoir study, Lower Eocene Misoa reservoirs, VLA-6/9/21 Area, Block I, Phase 2, Stage 2, Lagunillas Field, north‐central Lake Maracaibo, Venezuela ». GEOPHYSICS 62, n^o 5 (septembre 1997) : 1496–509. http://dx.doi.org/10.1190/1.1444253.

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Twenty‐eight geologically targeted, field development opportunities, including a variety of deeper pool opportunities that could significantly add to Maraven's (affiliate of PDVSA) reserve base, are identified in Lower Eocene Misoa reservoirs in the Stage 2 Area in Block I in north‐central Lake Maracaibo, Venezuela with the help of integrated geophysical, geological, petrophysical, and engineering analyses. Seismic rms amplitudes are instrumental in detecting and mapping trends of lithofacies and were integrated into stratigraphic models. Amplitude response to net sand thickness is a linear relationship. The amplitude signature also captures hydrocarbon charge as evidenced by bright amplitudes coincident with structural, fault‐bounded culminations. These direct hydrocarbon indicators (DHI) can result from as low as 2% miscible gas fraction within the hydrocarbon column.

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Mahmud, Hamzah Zamzami, Satrio E. Hapsoro et Guntur Ghiffari. « GEOLOGICAL MAPPING AND PROVENANCE ANALYSIS : AS THE KEY TO IDENTIFY DISTRIBUTION OF MUD DIAPIR AND ITS IMPLICATION ON COAL RESERVES IN PT. ARUTMIN INDONESIA SITE SENAKIN ». Prosiding Temu Profesi Tahunan PERHAPI 1, n^o 1 (29 mars 2020) : 817–24. http://dx.doi.org/10.36986/ptptp.v1i1.123.

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ABSTRAK Identifikasi keberadaan diapir merupakan hal esensial dalam pertambangan batubara mengingat sifatnya yang seperti intrusi dapat mengurangi cadangan batubara. Seperti yang teramati pada area pertambangan PT Arutmin Indonesia. Kehadiran mud diapir pada PIT HG telah terbukti mengurangi cadangan batubara, dengan luas area terdampak 0,7 Ha. Selain itu, beberapa diapir diperkirakan belum terpetakan karena terletak di bawah permukaan dan belum tersentuh oleh pengeboran eksplorasi PT Arutmin Indonesia, sehingga tanda-tanda permukaan seperti singkapan batuan dan struktur geologi maupun provenance diapir dapat menjadi petunjuk yang penting. Oleh sebab itu, tujuan penelitian ini adalah untuk mengetahui pola distribusi dan korelasi antara keberadaan diapir dengan struktur geologi, stratigrafi, dan provenance teridentifikasi yang kemudian dapat digunakan untuk memperkirakan persebaran diapir lainnya. Analisis dilakukan pada data primer hasil pemetaan geologi lapangan sebagai representasi struktur geologi maupun stratigrafi makro sebagai identifikator provenance. Hasil pemetaan lapangan seluas 60 km2 menunjukkan daerah penelitian terdiri dari tiga satuan batuan, yaitu satuan batupasir-batulempung termasuk lima singkapan diapir di dalamnya, satuan batulempung, dan satuan intrusi andesit. Satuan batupasir-batulempung memiliki kesetaraan dengan Formasi Tanjung yang merupakan formasi batuan sedimen tertua di daerah penelitian. Struktur geologi yang berkembang pada daerah penelitian adalah sesar geser menganan serta sesar geser mengiri yang berperan besar sebagai pengontrol keterdapatan diapir. Analisis stratigrafi menunjukkan provenance mud diapir berasal dari satuan batupasir-batulempung, Formasi Tanjung. Berdasarkan hasil analisis di atas, persebaran mud diapir berkorelasi dengan persebaran struktur geologi terutama sesar geser dan persebaran satuan batupasir-batulempung. Karena hal tersebut, maka pada area Tambang Senakin terdapat potensi keberadaan mud diapir yang tidak tersingkap di permukaan dan dapat menyebabkan hilangnya cadangan batubara termodelkan yang jauh lebih besar dari yang telah terbukti saat ini. Sebagai langkah preventif untuk mengetahui keberadaan diapir yang belum teridentifikasi, maka penulis membuat peta potensi keterdapatan diapir pada area penelitian di PT. Arutmin Indonesia Tambang Senakin. Untuk mendapatkan hasil yang lebih baik, penulis menyarankan pihak pelaksana tambang untuk melakukan analisis geolistrik pada titik yang telah direkomendasikan penulis. Kata kunci: mud diapir, Formasi Tanjung, analisis stratigrafi, pemetaan geologi lapangan, cadangan batubara ABSTRACT Identifying diapir occurrence is essential in coal mining activities knowing it behaves like an intrusion that can lead to a reduction in coal reserve. As we can observe in PT Arutmin Indonesia mining field. The presence of mud diapir on PIT HG has been proved to cut down its coal reserve, with the total area affected is 0,7 Ha. Since not all of the mud diapirs are exposed to the surface, we suspected that some of them are still yet to be found by PT Arutmin Indonesia’s exploration. Hence, diapir provenance and surface hints such as outcrop and geological structure can be a crucial indication. Therefore, this study objectives are to identify distribution and correlation between diapir occurrence and geological structures, stratigraphy, and its identified provenance that can be used to estimate other diapirs. This study began with geological mapping to identify the geological structure and its stratigraphy. Stratigraphic analysis is carried out as provenance identifier. Geological mapping in 60 km2 area concluded that the area have three lithological units, sandstone-claystone unit including five diapir outcrops, claystone unit, and andesite intrusion unit. Sandstone-claystone unit is equivalent to Tanjung Formation which is the oldest sedimentary rocks formation in the area. Dextral strike slip and sinistral strike slip faults which are found in the area considered to have a significant effect on diapirs occurrence. Further stratigraphic analysis shows that the the mud diapir’s provenance is from Tanjung Formation. Based on these analyses, we conclude that mud diapir occurrence has a good correlation to geological structures especially the strike slip faults and sandstone-claystone unit distribution. Consequently, Senakin Mine Field has a chance of losing its potential coal reserve much bigger than previously estimated due to unidentified mud diapirs occurrence below the surface. We will provide a mud diapir occurence potential map as a preventive measure in identifying unknown diapirs. We also suggest doing subsurface resistivity analysis for further detailed and better results. Keywords: mud diapir, Tanjung formation, stratigraphic analysis, geological mapping, coal reserve

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Fulton, R. J. « Surficial geology mapping at the Geological Survey of Canada : its evolution to meet Canada's changing needs ». Canadian Journal of Earth Sciences 30, n^o 2 (1 février 1993) : 232–42. http://dx.doi.org/10.1139/e93-020.

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The Geological Survey of Canada has been making surficial geology observations since it was founded in 1842. In addition to geological interest, early surficial geology information was gathered to aid in agriculture, forestry, hydrogeology, and engineering. The first regional surficial geology map was published in 1863, and since the early 1880's systematic surficial geology mapping has been a facet of the Survey's work.The first surficial geology specialist, R. Chalmers, worked for the Geological Survey during the last two decades of the nineteenth century. From then until 1930, when an official surficial geology unit was established, the Survey always had at least one surficial geologist on staff. From 1930 until 1960 groundwater-related studies were a major focus of surficial geology work. From 1950 to 1970 surficial geology mapping efforts were expanded to meet the demands generated by a booming economy. Since 1970 in addition to traditional uses, surficial geology information has been adapted to locating orebodies and evaluating environmental impacts.Early map legends presented surficial materials as stratigraphic units, or in terms of genesis and texture with little description or explanation. By the 1930's, the legend had evolved into a brief descriptive paragraph similar to that used on many Geological Survey of Canada maps today. With demands of the 1970's and 1980's for detailed descriptive information, especially to aid in assessing environmental impacts, new parameter legends were developed and extensive descriptive tables attached to maps. The current challenge is to adapt surficial geology mapping to the world of the geographic information system.

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Bodard, J. M., J. G. Creer et M. W. Asten. « Next Generation High Resolution Airborne Gravity Reconnaissance in Oil Field Exploration ». Energy Exploration & ; Exploitation 11, n^o 3-4 (juillet 1993) : 198–234. http://dx.doi.org/10.1177/0144598793011003-402.

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Simple modelling studies of gravity fields using elementary structural forms, oilfield-type structures and geological reconnaissance situations, show that gravity gradiometry technology offers significant petroleum exploration potential. In geological environments of interest, gravity gradients are primarily due to density displacement along (near) vertical boundaries. Gradient images therefore reveal the edges and corners of intrusions, faults, fault intersections, and other such structures often associated with hydrocarbon migration pathways and traps, and/or significant basinal trends. Recent technological advances may make gravity gradiometry an airborne reconnaissance tool capable of providing sensitivity and resolution superior to the best gravimetry available today. This capacity, and the array of gradient components that may be measured, will embellish aspects of the gravity field important to developing regional geologic interpretations. While the potential advantage of gravity gradiometry is greater lateral resolution and sensitivity from a moving platform, the disadvantage is the high sensitivity to topographic and shallow buried irregularities unrelated to the deeper geological structures of interest. A further difficulty is the complex gravity field representations produced for density structures of certain geometries. Buried features that have near surface expressions will be easiest to map. However, full use of gravity gradient technology will require application-focused data processing techniques and new interpretation skills. When the technology becomes commercially available it could find application in preseismic reconnaissance, structural (and possibly stratigraphic) mapping, acreage management and assessment, and in the evolution and mapping of controls on oilfield distribution. The technology could help develop exploration in remote and inaccessible areas, and provide a new look at well-explored regions. An immediate practical implementation appears to be in offshore exploration applications, possibly linked to deepwater exploitation strategies.

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Marquis, Robert, et Godfrey S. Nowlan. « Stratigraphic position and conodonts of the early Middle Ordovician Melbourne Formation, Quebec ». Canadian Journal of Earth Sciences 28, n^o 5 (1 mai 1991) : 816–21. http://dx.doi.org/10.1139/e91-070.

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A new fossil locality yielding rare conodonts of probable late Arenig to early Llanvirn age in the previously unfossiliferous Melbourne Formation of the Appalachian Humber Zone has been discovered in the Eastern Townships of Quebec. The presence of a continental-margin fauna at the northeast end of the Sutton Mountains Anticlinorium suggests a continuity of sedimentation, and this contradicts previous suggestions of a major disconformity between the Lower and Middle Ordovician rocks in this part of the Quebec Reentrant. Moreover, recent geological mapping shows that the contact between the conodont-bearing Melbourne Formation and the underlying Sweetsburg Formation of the Oak Hill Group is conformable and gradational. Consequently, it is proposed that the graphitic limestone of the Melbourne Formation represents the youngest unit of the Cambro-Ordovician Oak Hill Group.

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Mozherovsky, Anatoly V. « Practical Application of the Mineralogical Mapping Method for Stratigraphy of the Cretaceous Deposits of Southern Primorye (Russian Far East) ». Minerals 11, n^o 8 (4 août 2021) : 840. http://dx.doi.org/10.3390/min11080840.

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Highly ordered mixed-layer formations of chlorite–smectite (corrensite) and mica–smectite (rectorite) were found in the volcanogenic–sedimentary rocks of Southern Primorye. They have shown a rather narrow “living” time interval (Cretaceous–Paleogene). The associations of corrensite and rectorite with chlorite, mica, kaolinite, and laumontite have great value in labeling. Their study would determine the time and thickness parameters of sedimentation conditions, the nature of the transformation stages, the physicochemical and climatic parameters of the accumulation of the depositional material, and the geological history and stratigraphic construction of Mesozoic–Cenozoic volcanogenic–sedimentary rocks of the Primorye Region.

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GALVÃO, PAULO, RICARDO HIRATA, ARNALDO CORDEIRO, DANIELA BARBATI et JORGE PEÑARANDA. « Geologic conceptual model of the municipality of Sete Lagoas (MG, Brazil) and the surroundings ». Anais da Academia Brasileira de Ciências 88, n^o 1 (2 février 2016) : 35–53. http://dx.doi.org/10.1590/0001-3765201520140400.

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ABSTRACT The study area is located in the state of Minas Gerais, Brazil, among the municipalities of Pedro Leopoldo, Matozinhos, and Sete Lagoas, with Velhas River as the eastern boundary. It is located in the São Francisco Craton, where carbonated argillo-arenaceous sediments are emplaced giving origin to the Bambuí Group, in the São Francisco Basin. Despite the geological knowledge previously developed, the region needs work on integration and detailing of such information. For this reason, the main objective was to contribute to the quality of the geologic cartography, the spatial distribution, and the structural framework geometry. Thus, geologic mapping, aerial photography interpretation, and evaluation of 270 lithologic well profiles were carried out. It was possible to establish a new geologic perspective of the region by obtaining the detailed geologic map of the municipality of Sete Lagoas, 14 geologic cross sections, and a geologic conceptual model. The study showed that the area is within a basin border, presenting a geometry conditioned by horst and graben system controlled by faulting. This structural feature displaced stratigraphic sequences positioning them side by side with lithologic sequences with different ages.

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Sinha, Ajit K. « Stratigraphic mapping of sedimentary formations in southern Ontario by ground electromagnetic methods ». GEOPHYSICS 55, n^o 9 (septembre 1990) : 1148–57. http://dx.doi.org/10.1190/1.1442931.

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Multifrequency and transient electromagnetic (EM) soundings were done at several locations in southern Ontario to evaluate the possibility of stratigraphic mapping of gently dipping sedimentary formations by ground EM techniques. The possibility of detecting structural features such as folds, faults, and grabens in the formations was also explored. The two EM techniques were used to map a buried river valley near the village of Copetown, about 75 km southwest of Toronto. The valley, buried under fairly resistive glacial till and dolomite formations was mapped at depths ranging from 100 to 200 m. The interpreted shape and depth of the valley agreed well with information from a high resolution seismic reflection survey and data from wells penetrating the bedrock. Transient EM (TEM) data, using square transmitter loops with side dimensions comparable to the transmitter‐receiver separation for the multifrequency system, was found to be less affected by the presence of shallow conductors and lateral inhomogeneities than the multifrequency data, and had greater depth of investigation. TEM soundings were made on five additional profiles in the area. Lithologic logs from old oil and gas wells located near the profiles provided information for comparison with EM sounding interpretations. The depths to various dolomite, shale, and limestone formations interpreted from EM data agreed well with drillhole information. The EM soundings also detected structures in the Paleozoic formations such as faults and folds that were not previously known. The soundings confirmed the existence of a graben at one site at a depth of 100 m, which was postulated from logs from a cluster of closely spaced drillholes by geologists. The survey results indicated that EM sounding methods can be used for stratigraphic mapping in areas where detailed geological information is unavailable either because the bedrock is concealed by overburden, or when drillholes are sparsely distributed.

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Gersztenkorn, Adam, et Kurt J. Marfurt. « Eigenstructure‐based coherence computations as an aid to 3-D structural and stratigraphic mapping ». GEOPHYSICS 64, n^o 5 (septembre 1999) : 1468–79. http://dx.doi.org/10.1190/1.1444651.

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Coherence measures applied to 3-D seismic data volumes have proven to be an effective method for imaging geological discontinuities such as faults and stratigraphic features. By removing the seismic wavelet from the data, seismic coherence offers interpreters a different perspective, often exposing subtle features not readily apparent in the seismic data. Several formulations exist for obtaining coherence estimates. The first three generations of coherence algorithms at Amoco are based, respectively, on cross correlation, semblance, and an eigendecomposition of the data covariance matrix. Application of these three generations to data from the Gulf of Mexico indicates that the implementation of the eigenstructure approach described in this paper produces the most robust results. This paper first introduces the basic eigenstructure approach for computing coherence followed by a comparison on data from the Gulf of Mexico. Next, Appendix A develops a theoretical connection between the well‐known semblance and the less well‐known eigenstructure measures of coherence in terms of the eigenvalues of the data covariance matrix. Appendix B further extends the analysis by comparing the semblance- and eigenstructure‐based coherence measures in the presence of additive uncorrelated noise.

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Read, J. J. « Seismic reflection investigations of the Hellyer orebody and Que-Hellyer volcanics, North West Tasmania ». Exploration Geophysics 20, n^o 2 (1989) : 159. http://dx.doi.org/10.1071/eg989159.

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Two separate seismic reflection surveys have been conducted over Aberfoyle Resources Hellyer orebody and the enclosing Cambrian Que-Hellyer volcanics. The initial survey, conducted as a test case to determine if seismic reflection techniques could detect massive sulphide orebodies at depth, successfully identified the Hellyer orebody, which was found to have a characteristic seismic expression. Identification and mapping of stratigraphic units within the Que-Hellyer volcanics was also possible due to the good geological control available.The second survey did not successfully identify the Hellyer orebody, although some information relating to the structure of the enclosing basin could be inferred from the seismic data. Due to data degradation conventional seismic interpretation techniques could not be applied to the second survey.High resolution seismic surveys can detect massive sulphide orebodies if low velocity overburden problems are eliminated and high frequency data is collected. High resolution surveys can also provide structural and stratigraphic information between widely spaced drill holes in volcanic terrains.

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Lucchi, F. « Chapter 5 Stratigraphic methodology for the geological mapping of volcanic areas : insights from the Aeolian archipelago (southern Italy) ». Geological Society, London, Memoirs 37, n^o 1 (2013) : 37–53. http://dx.doi.org/10.1144/m37.5.

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Sinnyovsky, Dimitar. « Precambrian metamorphites as part of the petrographic diversity of Rila Geopark ». Review of the Bulgarian Geological Society 82, n^o 1 (mars 2021) : 11–29. http://dx.doi.org/10.52215/rev.bgs.2021.82.1.3.

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The petrographic diversity of Rila Mountain is an important prerequisite for the development of Rila Geopark and its nomination for UNESCO Geopark. According to the principle of the thematic geodiversity, the leading theme of the geopark – glacial landscapes, is complemented by the remarkable petrographic diversity of igneous and metamorphic rocks, in which alpine glacial forms are developed. Following a recent review of the intrusive rocks that make up the Rila-West Rhodope Batholith, the concept of Rila Geopark would not be complete without a retrospective of the metamorphic rocks that are an integral part of its petrographic diversity. The different approaches (lithodemic and lithotectonic) to the mapping of the Rila-Rhodope Massif divided the geologists into two camps. This led to a discrepancy in terminology and nomenclature of the metamorphic units, which is unacceptable in the context of the educational priority of the geopark. For the purpose of geotourism, clear and understandable interpretations are required to provoke the visitors’ interest in geological processes and phenomena, rather than confusion and perplexity. This article is a historical overview of the geological study of the metamorphic terrains in Rila Mountain with a scheme of lithodemic units based on the existing lithostratigraphic nomenclature. This approach allows the preservation of the names of the lithostratigraphic units, whose toponymic adjectives derive from well known geographical features in the Rila-Rhodope Massif. The rank term is replaced by a lithological or descriptive term, which frees the nomenclature from the dogmatic restrictions of the stratigraphic code and reduces the distance between the strictly scientific and popular science approach used for interpretation of geological information in a popular language accessible to the general public. This methodology is consistent with the approach recommended for mapping of non-stratified bodies on the Geological Map of the Republic of Bulgaria at a scale 1:50 000.

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Veklych, Yu. « Map of Quaternary formations of Ukraine in scale 1:2,500,000 ». Journal of Geology, Geography and Geoecology 28, n^o 2 (6 juillet 2019) : 367–76. http://dx.doi.org/10.15421/111935.

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The article announces a new map of Quaternary formations on the territory of Ukraine on the scale 1:2,500,000. It considers the prerequisites for the preparation of this map and summarises more than a century of historical research and mapping of the Quaternary formations on the territory of Ukraine. Due to the continuity of scientific research, an extremely developed theoretical and methodological basis of both research and mapping of Quaternary formations has been formed in the country. This is also due to the extraordinary diversity of the geological structure of the Quaternary cover, due to the presence of two mountain systems, lowland areas (including within them several deflections and two crystalline foundations), as well as due to the presence of two seas (including the continental shelf, slope and deep-water zone). A very wide spectrum of facies and formations is also listed (including a thick loess-soil cover, facies of two glaciers of different ages, alluvia, estuary, marine shelf, deep-water and etc.). Attention is focused on two important problems of mapping Quaternary cover. The first is related to new views on the origin of the subaerial cover. The significance of the new (geo-eolian) factor is disclosed, which determined both the thickness and lithological properties of the strata of each paleogeographic stage (of climatoliths) of each separate section, and the stratigraphic structure of the loess-soil cover. Spatial patterns of the structure of the subaerial cover are briefly described, in particular, the mosaic division into areas with a homogeneous stratigraphic structure (type-sections), due to the corresponding geo-eolian mode (sequence). The second problem concerns the ways of visualization of the geological structure of Quaternary sediments on the map. Two principles of reflection of the Quaternary cover are considered, and the disadvantages and advantages of each of them are indicated. Promising ways to map the Quaternary subaerial cover on the basis of ideas about its mosaic structure are proposed. A solution to the problem of various principles of visualization of the Quaternary cover is recommended involving compilation of «multi-visual» maps based on their interactive reissuing (re-design) with modern geographic information systems in accordance with various principles of visualization of the structure of the Quaternary. It has been proposed to use the above scientific approaches in the mapping of the Quaternary deposits of Europe and the World, and also to take into account the geo-eolian factor in the studies of the subaerial cover.

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Zhang, Zhenhua, Yanbin Wang et Pan Wang. « On a Deep Learning Method of Estimating Reservoir Porosity ». Mathematical Problems in Engineering 2021 (8 février 2021) : 1–13. http://dx.doi.org/10.1155/2021/6641678.

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Porosity is an important parameter for the oil and gas storage, which reflects the geological characteristics of different historical periods. The logging parameters obtained from deep to shallow strata show the stratigraphic sedimentary characteristics in different geological periods, so there is a strong nonlinear mapping relationship between porosity and logging parameters. It is very important to make full use of logging parameters to predict the shale content and porosity of the reservoir for precise reservoir description. Deep neural network technology has strong data structure mining ability and has been applied to shale content prediction in recent years. In fact, the gated recurrent unit (GRU) neural network has further advantage in processing serialized data. Therefore, this study proposes a method to predict porosity by combining multiple logging parameters based on the GRU neural network. Firstly, the correlation measurement method based on Copula function is used to select the logging parameters most relevant to porosity parameters. Then, the GRU neural network is used to identify the nonlinear mapping relationship between logging data and porosity parameters. The application results in an exploration area of the Ordos basin show that this method is superior to multiple regression analysis and recurrent neural network method, which indicates that the GRU neural network is more effective in predicting a series of reservoir parameters such as porosity.

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Putranto, Thomas Triadi, Muhammad Iman Luthfi, Nurakhmi Qadaryati, Narulita Santi et Wahju Krisna Hidajat. « Aquifer System, Recharge-Discharge Zone and Groundwater Basin Boundary Mapping to Support Open and Transparent Water Data, Case Study : Karangkobar Groundwater Basin ». E3S Web of Conferences 125 (2019) : 01012. http://dx.doi.org/10.1051/e3sconf/201912501012.

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Sustainable groundwater management based on groundwater basin (GWB) must be equipped with comprehensive information including the characteristic of hydrogeology. This management method is very useful for governments to design some regulations, such as tax and conservation zone. Nowadays, not only the government but the public society can also have access to know this management. Open and transparent groundwater application needs sufficient data. Based on that issue, this research aims to provide the geological and hydrogeological conditions of GWB, define the aquifer configurations, and determine the groundwater recharge-discharge zones and the type of GWB boundary on Karangkobar GWB. The methods applied to the study are 1) mapping the geological and hydrogeological condition; 2) reconstruction of subsurface stratigraphic condition; and 3) overlay four parameters of the recharge-discharge zone. The Karangkobar GWB consists of the unconfined and confined aquifer of High Plain Aquifer, where the groundwater flows from north and east heading southward and westward. Seven boundary types bounded the Karangkobar GWB. The map can also support the open and transparent water data application system, it will also ease the party that will conduct an assessment to design regulation regarding the groundwater management.

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Intan, Fadhlan S. « GEOARKEOLOGI CEKUNGAN SOA, FLORES, NUSA TENGGARA TIMUR ». Siddhayatra 23, n^o 1 (23 août 2018) : 31. http://dx.doi.org/10.24832/siddhayatra.v23i1.124.

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Soa Basin, which belongs to Ngada Regency and Nagekeo Regency, is located on Flores Island, with many cultural stays, among others, from the Paleolithic period, which has not been too concerned by environmental researchers, especially geoarkeology. This is the issue that covers general geological conditions. The purpose of this research is to mapping the surface geology in general as an effort to present geological information related to archeological site. The aim is to know the geomorphological, stratigraphic aspects of the archaeological sites. The research method is done through literature review, survey, field data analysis and interpretation. Environmental observations provide information on the landscape of the study area consisting of terrestrial morphology units, and weak wavy morphology units. The river is centripetal flow pattern, with the old river, mature-old river, periodic/permanent river, and episodik /intermittent river. Constituent rocks are volcanic breccias, tuffs, conglomerates, and alluvial deposits. The geological structure is a fracture of the normal fault type. Exploration in the Soa Basin has listed 12 paleolithic sites. From the classification of petrology, litik tools made of jasper, chert, andesite, and basalt rocks. Rock as a raw material litik, found in Soa Basin and surrounding areas, both in the form of outcrops and boulder.

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Lang, S. C., N. Ceglar, S. Forder, G. Spencer et J. Kassan. « HIGH RESOLUTION SEQUENCE STRATIGRAPHY, RESERVOIR ANALOGUES, AND 3D SEISMIC INTERPRETATION—APPLICATION TO EXPLORATION AND RESERVOIR DEVELOPMENT IN THE BARYULAH COMPLEX, COOPER BASIN, SOUTHWEST QUEENSLAND ». APPEA Journal 42, n^o 1 (2002) : 511. http://dx.doi.org/10.1071/aj01028.

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Gas exploration and reservoir development in the Baryulah area, Cooper Basin, southwest Queensland has focussed on the fluvial-lacustrine, Permian coal-bearing Patchawarra Formation, Murteree Shale, Epsilon and Toolachee Formations. Geological interpretation of drilling and 3D seismic data has benefitted from integration of sequence stratigraphic concepts with the judicious use of reservoir analogues and seismic attribute mapping. Initially, a coherent regional chronostratigraphic framework was established, based on broad palynological zonations, and correlating extensive lacustrine flooding surfaces and unconformities, tied to 3D seismic reflectors. This framework was subdivided by using local key surfaces identified on wireline logs (usually high-gamma shaly intervals overlying coals), resulting in recognition of numerous high-resolution genetic units. Wireline log character, calibrated by cores from analogous fields around the Cooper Basin and supported by analogue studies, forms the basis for a logfacies scheme that recognises meandering fluvial channels, crevasse splays, floodplain/basin, and peat swamps/mires. Fluvial stacking patterns (aggradational, retrogradational or progradational), produced by the ratio of sediment supply to accommodation within each genetic unit, were used to help determine depositional systems tracts (alluvial lowstand, transgressive, or highstand) and likely reservoir connectivity. Log signature maps for genetic intervals form the basis of palaeogeographic mapping. Modern and ancient depositional analogues were used to constrain likely facies distribution and fluvial channel belt widths. Syndepositional structural features, net-to-gross trends, and seismic attribute mapping are used to guide the scale, distribution and orientation of potential reservoir trends. When used in conjunction with structural and production data, the palaeogeographic maps help develop stratigraphic trap play concepts, providing a predictive tool for locating exploration or appraisal drilling opportunities.

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Stalker, Linda, David Dewhurst, Yanhua Zhang, Peter Schaubs, Ben Clennell, Yohan Suhardiman, Andrew Maxwell et al. « Evaluation of the Petrel Sub-basin as a northern Australia CO2 store : future decarbonisation hub ? » APPEA Journal 60, n^o 2 (2020) : 765. http://dx.doi.org/10.1071/aj19180.

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The Northern Australia CO2 Store Project has extended investigations for safe, long-term containment of large volumes of CO2 (up to 100 million tonnes) to support liquefied natural gas and other industries in a decarbonised future. Most natural gas fields in the Petrel Sub-basin and the surrounding region have relatively high native CO2 content. This collaborative project improved storage characterisation, evaluated geomechanical risks and estimated engineering demands necessary to progress the concept to ‘prospect’ and ‘resource’. New data have significantly advanced the geological and structural understanding in the region, improving chrono- and litho-stratigraphic correlations, with new well ties across the basin. However, the re-mapping has thrown up new questions that require additional data (e.g. new stratigraphic wells, 3D seismic data) to address those knowledge gaps. Geomechanical modelling in the area has tested (to extreme levels) the potential impact of injection on faults in the area, further de-risking the likelihood of upward migration and leakage. The region could utilise an abundance of energy and feedstocks in the form of solar, natural gas, hydrogen and CO2 to become a future decarbonisation and industrial hub while managing major emissions with offshore CO2 storage.

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Strong, P. C., G. R. Wood, S. C. Lang, A. Jollands, E. Karalaus et J. Kassan. « HIGH RESOLUTION PALAEOGEOGRAPHIC MAPPING OF THE FLUVIAL-LACUSTRINE PATCHAWARRA FORMATION IN THE COOPER BASIN, SOUTH AUSTRALIA ». APPEA Journal 42, n^o 1 (2002) : 65. http://dx.doi.org/10.1071/aj01005.

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Fluvial-lacustrine reservoirs in coal-bearing strata provide a particular challenge for reservoir characterisation because of the dominance of coal on the seismic signature and the highly variable reservoir geometry, quality and stratigraphic connectivity. Geological models for the fluvial gas reservoirs in the Permian Patchawarra Formation of the Cooper Basin are critical to minimise the perceived reservoir risks of these relatively deep targets. This can be achieved by applying high-resolution sequence stratigraphic concepts and finescaled seismic mapping. The workflow begins with building a robust regional chronostratigraphic framework, focussing on widespread lacustrine flooding surfaces and unconformities, tied to seismic scale reflectors. This framework is refined by identification of local surfaces that divide the Patchawarra Formation into high-resolution genetic units. A log facies scheme is established based on wireline log character, and calibrated to cores and cuttings, supported by analogue studies, such as the modern Ob River system in Western Siberia. Stacking patterns within each genetic unit are used to determine depositional systems tracts, which can have important reservoir connectivity implications. This leads to the generation of log signature maps for each interval, from which palaeogeographic reconstructions are generated. These maps are drawn with the guiding control of syn-depositional structural features and net/ gross trends. Estimates of fluvial channel belt widths are based on modern and ancient analogues. The resultant palaeogeography maps are used with structural and production data to refine play concepts, as a predictive tool to locate exploration and development drilling opportunities, to assess volumetrics, and to improve drainage efficiency and recovery during production of hydrocarbons.

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Pons, Jose Maria, Enric Vicens, Yolanda Pichardo, Javier Aguilar, Angélica Oviedo, Gloria Alencaster et Pedro García-Barrera. « A New Early Campanian Rudist Fauna from San Luis Potosi in Mexico and Its Taxonomic and Stratigraphic Significance ». Journal of Paleontology 84, n^o 5 (septembre 2010) : 974–95. http://dx.doi.org/10.1666/09-169.1.

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A rudist fauna composed of the radiolitids Potosites tristantorresi new genus, new species and Radiolites acutocostata (Adkins), the hippuritids Barrettia cf. ruseae Chubb, Torreites sanchezi (Douvillé), and Vaccinites vermunti Mac Gillavry, plagioptychids, and antillocaprinids is described from a rudist limestone succession in the central Mexican State of San Luis Potosí. The previously known species, one radiolitid from Texas and three hippuritids from the Caribbean Biogeographic Province, indicate the early Campanian. The new genus is a large radiolitid with a coiled and canaliculated left valve. New observations on R. acutocostata and V. vermunti shell morphology and variability are provided. Observations made on well preserved specimens of the latter species clarify the outer shell layer structure of the hippuritids right valve and has taxonomic implications. This is the first report of genus Torreites in Mexico and one of the northernmost records of genus Barrettia, already reported in southern Mexico from Chiapas State. This rudist limestone succession (informally ‘Temazcal limestones’ herein) is an easy-to-recognize cartographical unit; up to now it and Santonian and Turonian units have been mapped as the El Abra Formation in most available geological maps. Recognition of the successive carbonate platform intervals, between El Abra and Cardenas formations, improves the geological mapping and the understanding of the Mexican Gulf western margin evolution during the Late Cretaceous.

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Shcheglov, I. A., F. F. Akhunov, R. U. Eremenko et V. N. Komarov. « AT THE BEGINNING OF THE BIOSTRATIGRAPHY (TO THE 250TH ANNIVERSARY OF THE BIRTHDAY OF WILLIAM SMITH) ». Proceedings of higher educational establishments. Geology and Exploration, n^o 3 (25 juin 2018) : 74–80. http://dx.doi.org/10.32454/0016-7762-2018-3-74-80.

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The main side of the W. Smith’s work — geological mapping — has been shown to be expressed in the series of maps, created by him, and first of all in the «Map of layers of England and Wales». The layers represented for Smith an object for mapping. His stratigraphic tables constitute the lists of stratons, systemized in the order of their bedding and origin. W. Smith discovered a general sequence of 34 layers ofEnglandandWales, in more detailes separated the deposits, substracted later in the Jurassic system. Fossils were considered by W. Smith as specific features of layers, being mapped. The very combination of the characteristics of talented geologist — map-maker und collector of fossils — allowed making the famous conclusion that every layer contained the fossils, typical exactly for it. W. Smith showed the specifics and continuity of paleontological characteristics of different layers, predefined the oportunity of their recognition and identification and designed the base for the development of biostratigraphic method and historical geology in a whole. The short biographic data for Smith has been given.

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RONCATO, Jorge, Ana Luiza de CARVALHO ALMEIDA, Bárbara MACEDO et Matheus OLIVEIRA. « ANÁLISE GEOFÍSICA DA REGIÃO DO RIO CONCEIÇÃO, QUADRILÁTERO FERRÍFERO, ASSOCIADOS A DADOS DE CAMPO, PETROGRÁFICOS E DE IMAGENS AÉREAS ». Geosciences = Geociências 39, n^o 1 (19 mai 2020) : 47–63. http://dx.doi.org/10.5016/geociencias.v39i1.14613.

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The Quadrilátero Ferrífero region, located in the southeast portion of the São Francisco Craton, is one of the main metallogenic provinces in Brazil. Fieldwork, petrography, high-resolution airborne geophysics (magnetic and gamma-ray spectrometry data), and aerial images allowed us to produce a new map at the 1:25,000 scale, with important contributions in the lithotypes detailing, understanding of the geological structures and relationship between the different stratigraphic units. Interpretation of airborne geophysical data integrated with field structural and lithological observations were successfully employed in the creation of the litho-structural framework in a poorly exposed Proterozoic and Archean terrain. Airborne gamma-ray spectrometry data aided in the mapping process in areas with regolith cover including erosional ridges. The magnetic total derivative image revealed regional and local structures. In addition, our work details the units of occurrence of Rio das Velhas and Minas Supergroup. The aerial coverage of the Mindá and Santa Quitéria formations strongly increased, as well as the area of the Cauê Formation was better defined. The new geological map provides many improvements over the pre-existing maps. New lithological facies and structures were identified and others become more visible and lithologicalboundaries are refined or confirmed.

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Rasmussen, Erik S., Karen Dybkjær et Stefan Piasecki. « The Billund delta : a possible new giant aquifer in central and western Jutland ». Geological Survey of Denmark and Greenland (GEUS) Bulletin 4 (20 juillet 2004) : 21–24. http://dx.doi.org/10.34194/geusb.v4.4773.

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The search for new, deep-seated drinking water resources in Denmark has increased significantly during the past five years as a result of the discovery of excessive amounts of nitrate, pesticides and other pollutants in shallow groundwater boreholes (e.g. Nygaard et al. 2004, this volume). To find and map these aquifers, a multidisciplinary sequence stratigraphic approach has successfully been applied to the Miocene deposits of southern Jutland, where especially the Odderup and Ribe Formations are known as a main aquifer for drinking water from several test wells (Rasmussen et al. 2002). Recently, a more systematic study of the Miocene succession in central and western Jutland has been initiated by the Geological Survey of Denmark and Greenland (GEUS) under contract with local authorities. It includes detailed sedimentological descriptions of outcrops, sedimentological andlog-interpretations of new stratigraphic boreholes and interpretation of new high-resolution seismic data (Fig. 1). A number of outcrops and wells have been studied palynologically, resulting in a detailed dinoflagellate cyst stratigraphy and in palynofacies interpretations. The results of these studies have been integrated in the regional geological and stratigraphic model (Fig. 2). Two new aquifers have been discovered: the Bastrup sand and the Billund sand. The Bastrup sand has already been exploited as a main aquifer in central and southern Jutland, and has been referred to either the Ribe or Odderup Formations. However, new stratigraphic results reveal that the Bastrup sand is a separate unit in the Miocene succession. The Billund sand is a deep-seated aquifer located more than 100 m and often more than 150 m deep, and is therefore not penetrated by standard water supply wells which rarely reach c. 100 m. The Billund sand was first revealed by multichannel seismic data deriving from former oil-exploration carried out in the Billund area (Fig. 3A). The resolution of these seismic data is very poor, but one interpretation of the dipping reflectors (clinoforms) seen in Fig. 3A was of a delta complex. This agrees with outcrop studies along the fjords of eastern Jutland which suggest that a spit complex was deposited in this area during the Early Miocene. The Billund sand was tested by the Vandel Mark well in 2001, which penetrated c. 40 m of sand at a depth of 200 m. The presence of a regional major sand body was later confirmed by new high-resolution seismic data and by the Billund and Løvlund wells in 2002. The Billund well penetrated 50 m of medium- to coarse-grained sand, and chemical tests of the water quality were good. However, a water supply well at Fjand in western Jutland has had problems with so-called ‘brown water’ – water enriched in organic matter (humus). Saline water may also be expected close to older deep-seated faults. This paper summarises the results of a mapping programme of the Billund sand initiated in the summer of 2003.

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Jamšek Rupnik, Petra, Manja Žebre et Giovanni Monegato. « Late Quaternary evolution of the sedimentary environment in Modrejce near Most na Soči (Soča Valley, Julian Alps) ». Geologija 63, n^o 2 (7 décembre 2020) : 295–309. http://dx.doi.org/10.5474/geologija.2020.022.

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Geomorphological and geological mapping have long been used to study the glacial history of the Slovenian Alps, but many uncertainties remain regarding the time and extent of Pleistocene glaciations there. Glacial landforms and undisturbed glacial deposits are rare in the areas of the former glacier terminus, especially in the Soča Valley, where large discrepancies in the interpretation of the extent of the former Soča Glacier have been reported. Early studies proved inconclusive as to whether one or two glaciations extended into the Soča Valley as far as Most na Soči. In order to answer this question, the Quaternary sedimentary succession and landforms in the Modrejce Valley near Most na Soči were investigated. New geological and geomorphological field data allow the interpretation of the sedimentary environment and the stratigraphic relationships between different units. In response to glacial dynamics, the sedimentation developed from glaciofluvial and glaciolacustrine to fully glacial environments, followed by slope deposition. At higher altitudes lateral moraines are preserved, while the staircase-like slope below has been carved into older glacial, glaciofluvial and glaciolacustrine deposits by glacial and post-glacial processes, including fluvial erosion and slope dynamics. We conclude that the succession studied here was deposited over the course of two different glacial advances – LGM and pre-LGM. Our study thus suggests that the Soča Glacier extended as far as the area of Most na Soči twice over the course of the late Quaternary.

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Swanson, Eric. « History of Field Observations on Volcanic Rocks of Western Mexico, Pre-Columbian to Recent ». Earth Sciences History 30, n^o 1 (1 décembre 2011) : 106–34. http://dx.doi.org/10.17704/eshi.30.1.p68hl442l6w11036.

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By the time the first detailed reports on western Mexico's volcanic rocks had begun to appear in the 1970s, most of the earlier observations on these rocks and most knowledge of those who made these observations were all but forgotten. A review of previous field observations in this region shows, however, a long history of geologic discovery reflecting or even preceding developments elsewhere.Ethnological studies suggest that the Pre-Columbian inhabitants of the Sierra Madre Occidental (SMO) observed the characteristics of rock formations in their sierra homeland and understood something of the regional stratigraphic relationships. Late sixteenth and early seventeenth century explorers of the Spanish Colonial Period singled out volcanic rock known to them as piedra de malpaís for special recognition, and Padre Kino and his fellow explorers clearly recognized the volcanic origin of piedra de malpaís decades prior to similar observations in Europe. As the Spanish Colonial Period came to a close, Andrés Manuel del Río help organize a state-of-theart mining college in Mexico City where students were instructed in Werner's geognosy prior to their taking positions in Mexico's mining industry, most of it located in western Mexico's volcanic rocks.Although the first part of the tumultuous period between Mexico's revolutions of 1810 and 1910 saw few advances in geological knowledge, the reign of President Porfirio Díaz produced a geologic map of Mexico, the founding of the Instituto de Geología, and an ‘American invasion’ of geologists and mining engineers who locally gathered information on the nature of volcanic rocks of western Mexico. During the same period, Instituto geologist Ezequiel Ordóñez established the general stratigraphic sequence in the SMO, recognized the widespread occurrence of rhyolite there, and applied the petrographic microscope to the study of SMO volcanic rocks. The first identification of ignimbrites in the SMO came as a result of the World War II-era search for strategic minerals, and NASA's push to put a man on the Moon supported a series of student mapping projects producing the SMO's first geologic maps showing individual ignimbrite units and calderas.

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Hinojosa-Prieto, Hector R., Pantelis Soupios et Pavel Barsukov. « Subsurface Geological Characterization of the Late Neogene–Quaternary Argive Basin, Peloponnese, Greece Using Transient Electromagnetic Data and Vintage Stratigraphic Logs ». Geosciences 11, n^o 8 (28 juillet 2021) : 317. http://dx.doi.org/10.3390/geosciences11080317.

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The onshore and offshore clastic deposits of the Argive Basin and the Argolic Gulf, respectively, in Peloponnese, Greece, form a Late Neogene–Quaternary half-graben that connects with the Aegean Sea. The onshore Late Neogene–Quaternary sequence, comprised of chaotically intercalated cohesive and granular clastic deposits, is in angular unconformity with bedrock comprised of Triassic–Upper Cretaceous strongly-weathered, highly-fractured karstic limestones thrusted against Paleogene flysch deposits. While the surface geology of the Argive Basin is well-known, the subsurface geology remains both poorly mapped and understood. We utilized transient electromagnetic (TEM) soundings coupled with 185 vintage stratigraphic logs, current surface geology knowledge, and insights from available geophysical surveys to characterize the subsurface conditions of this sedimentary basin. We estimated the thickness of the young deposits (the depth to bedrock) and detected potential subsurface tectonic structures. The TEM-FAST 48HPC data acquisition system with integrated inversion and visualization software package was used with a single-loop dimension of 50 m × 50 m to collect a total of 329 TEM soundings at 151 stations scattered throughout the basin. The TEM station spacing varied from 200 to 750 m allowing the mapping of 80 km2. The total depth of investigation with the inverted TEM data and the lithology logs was 130 m and 183 m, respectively. The joint interpretation produced several quasi-two-dimensional electrical resistivity profiles that traverse the sedimentary basin in various azimuths and depth slices of average electrical resistivity covering the basin. The depth slices and the vintage stratigraphic logs revealed an uneven bedrock topography overlain by an irregularly thick (over 180 m) Late Neogene–Quaternary heterolithic sediment cover.

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Ivanov, Mikhail A., et James W. Head. « Stratigraphic and geographic distribution of steep-sided domes on Venus : Preliminary results from regional geological mapping and implications for their origin ». Journal of Geophysical Research : Planets 104, E8 (1 août 1999) : 18907–24. http://dx.doi.org/10.1029/1999je001039.

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Hradecká, Lenka, Radek Vodrážka et Daniel Nývlt. « Foraminifera from the Upper Cretaceous of northern James Ross Island (Antarctica) : a preliminary report ». Czech Polar Reports 1, n^o 2 (1 juin 2011) : 88–95. http://dx.doi.org/10.5817/cpr2011-2-8.

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The Cretaceous biostratigraphy of the James Ross Island region is generally based on palynomorphs and macrofossils (bivalves, ammonites). During geological mapping of the northern James Ross Island a number of samples from Upper Cretaceous lithologies were gathered to test the presence of foraminifers as a possible tool for stratigraphic evaluation of Upper Cretaceous strata. Limited number of samples did not provide foraminiferal content large enough to give relevant information for biostratigraphic conclusions. Samples from older sediments of Whisky Bay and Kotick Point formations (Albian – Turonian) were either not fossiliferous or contained scarce specimens of agglutinated foraminifers. Foraminiferal assemblages from younger sediments of Hidden Lake and Santa Marta formations (Coniacian – Campanian) contained species with both agglutinated and calcareous types of tests. Many of studied marine sediments were barren of foraminifers, probably due to late diagenetic secondary decalcification. Taxonomy of low-diversified assemblages was carried out and a biostratigraphical and palaeobiogeographical significance discussed.

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Weidenfeller, M., et T. Kärcher. « Tectonic influence on fluvial preservation : aspects of the architecture of Middle and Late Pleistocene sediments in the northern Upper Rhine Graben, Germany ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 87, n^o 1 (mars 2008) : 33–40. http://dx.doi.org/10.1017/s0016774600024021.

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AbstractRecent carried out core drillings in the Ludwigshafen/Speyer area permit an improved stratigrahical differentiation of the Plio-Pleistocene deposits in the northern Upper Rhine Graben. Lithofacies analysis, pollen analysis, heavy mineral analysis, and palaeomagnetical results, lead to a subdivision of ‘Kieslager’ (gravel-layers) and ‘Zwischenhorizonte’ (interlayers). In the scope of geological mapping near Mannheim and Speyer, the genesis and the stratigraphic position of Middle and Late Pleistocene fluvial terraces was re-assessed (‘Frankenthaler Terrasse’). The terrace has a complex composition, marking two phases of accretion followed by abandonment: a first phase took place in (Elsterian? to) Saalian times, the second phase during the Weichselian. Tectonism further complicates the sequence, in particular in the area between Ludwigshafen and Speyer, which is the SW rim of the ‘Heidelberger Loch’-structure. In this area ‘terraces’ occur they are the result of faulting rather than fluvial dissection alone.

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