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1
Beauchamp, Jacques, Alain Izart, and Alain Piqué. "Les bassins d'avant-pays de la chaîne hercynienne au Carbonifère inférieur." Canadian Journal of Earth Sciences 28, no. 12 (December 1, 1991): 2024–41. http://dx.doi.org/10.1139/e91-183.
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The evolution of marine sedimentary basins deformed by the Hercynian Orogeny was studied in Germany, France, Iberia, Northwest Africa, and North America in the Lower Carboniferous. These basins opened along strike–slip faults and were filled with turbidites and shelf deposits until the main compressive phase at the end of Visean and the Namurian. The infilling was interrupted with frequent volcanic episodes and gravity-induced movements. According to sedimentary vergence, these basins were set into two festoons on both sides of an elongated and emergent swell structured during the Devonian and corresponding to the internal zones of the orogen. These basins were filled during a general tectonic compression phase; they correspond to the foreland basins of the Hercynian belt.
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Iyer, Karthik, Henrik Svensen, and Daniel W. Schmid. "SILLi 1.0: a 1-D numerical tool quantifying the thermal effects of sill intrusions." Geoscientific Model Development 11, no. 1 (January 5, 2018): 43–60. http://dx.doi.org/10.5194/gmd-11-43-2018.
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Abstract. Igneous intrusions in sedimentary basins may have a profound effect on the thermal structure and physical properties of the hosting sedimentary rocks. These include mechanical effects such as deformation and uplift of sedimentary layers, generation of overpressure, mineral reactions and porosity evolution, and fracturing and vent formation following devolatilization reactions and the generation of CO2 and CH4. The gas generation and subsequent migration and venting may have contributed to several of the past climatic changes such as the end-Permian event and the Paleocene–Eocene Thermal Maximum. Additionally, the generation and expulsion of hydrocarbons and cracking of pre-existing oil reservoirs around a hot magmatic intrusion are of significant interest to the energy industry. In this paper, we present a user-friendly 1-D finite element method (FEM)-based tool, SILLi, which calculates the thermal effects of sill intrusions on the enclosing sedimentary stratigraphy. The model is accompanied by three case studies of sills emplaced in two different sedimentary basins, the Karoo Basin in South Africa and the Vøring Basin off the shore of Norway. An additional example includes emplacement of a dyke in a cooling pluton which forgoes sedimentation within a basin. Input data for the model are the present-day well log or sedimentary column with an Excel input file and include rock parameters such as thermal conductivity, total organic carbon (TOC) content, porosity and latent heats. The model accounts for sedimentation and burial based on a rate calculated by the sedimentary layer thickness and age. Erosion of the sedimentary column is also included to account for realistic basin evolution. Multiple sills can be emplaced within the system with varying ages. The emplacement of a sill occurs instantaneously. The model can be applied to volcanic sedimentary basins occurring globally. The model output includes the thermal evolution of the sedimentary column through time and the changes that take place following sill emplacement such as TOC changes, thermal maturity and the amount of organic and carbonate-derived CO2. The TOC and vitrinite results can be readily benchmarked within the tool to present-day values measured within the sedimentary column. This allows the user to determine the conditions required to obtain results that match observables and leads to a better understanding of metamorphic processes in sedimentary basins.
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Loreto, Maria Filomena, Camilla Palmiotto, Filippo Muccini, Valentina Ferrante, and Nevio Zitellini. "Inverted Basins by Africa–Eurasia Convergence at the Southern Back-Arc Tyrrhenian Basin." Geosciences 11, no. 3 (March 4, 2021): 117. http://dx.doi.org/10.3390/geosciences11030117.
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The southern part of Tyrrhenian back-arc basin (NW Sicily), formed due to the rifting and spreading processes in back-arc setting, is currently undergoing contractional tectonics. The analysis of seismic reflection profiles integrated with bathymetry, magnetic data and seismicity allowed us to map a widespread contractional tectonics structures, such as positive flower structures, anticlines and inverted normal faults, which deform the sedimentary sequence of the intra-slope basins. Two main tectonic phases have been recognised: (i) a Pliocene extensional phase, active during the opening of the Vavilov Basin, which was responsible for the formation of elongated basins bounded by faulted continental blocks and controlled by the tear of subducting lithosphere; (ii) a contractional phase related to the Africa-Eurasia convergence coeval with the opening of the Marsili Basin during the Quaternary time. The lithospheric tear occurred along the Drepano paleo-STEP (Subduction-Transform-Edge-Propagator) fault, where the upwelling of mantle, intruding the continental crust, formed a ridge. Since Pliocene, most of the contractional deformation has been focused along this ridge, becoming a good candidate for a future subduction initiation zone.
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MARE, L. P., M. O. DE KOCK, B. CAIRNCROSS, and H. MOURI. "APPLICATION OF MAGNETIC GEOTHERMOMETERS IN SEDIMENTARY BASINS: AN EXAMPLE FROM THE WESTERN KAROO BASIN, SOUTH AFRICA." South African Journal of Geology 117, no. 1 (June 1, 2014): 1–14. http://dx.doi.org/10.2113/gssajg.117.1.1.
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Andersen, T., G. A. Botha, and M. A. Elburg. "A late Mesozoic – early Cenozoic sedimentary recycling system on the Gondwana rifted margin of southeast Africa." South African Journal of Geology 123, no. 3 (September 1, 2020): 343–56. http://dx.doi.org/10.25131/sajg.123.0023.
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Abstract Detrital zircons in late Cretaceous – Palaeogene, calcareous sandstone and conglomerate deposited in continental basins on the southeastern African margin after the breakup of Gondwana have characteristic combinations of age and epsilon-Hf that indicate an origin by recycling of Palaeoproterozoic (Waterberg, Soutpansberg and Pretoria groups) and Phanerozoic (Karoo Supergroup) cover successions. The latter is dominant in the south and east (Boane, Mahosi, Chilojo Cliffs), and the Palaeoproterozoic sources in the northwest (Pafuri, Wright’s Tower, Masisi). This recycling and mixing regime was restricted to late Mesozoic and Palaeogene time in northeastern South Africa and adjoining parts of Mozambique and Zimbabwe. Detrital zircon distribution patterns in these deposits reflect the denudation history of the southern African continental surface after breakup of the Gondwana supercontinent.
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Papadimitriou, Nikolaos, Remy Deschamps, Vasilis Symeou, Christine Souque, Christian Gorini, Fadi Henri Nader, and Christian Blanpied. "The tectonostratigraphic evolution of Cenozoic basins of the Northern Tethys: The Northern margin of the Levant Basin." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 73 (2018): 77. http://dx.doi.org/10.2516/ogst/2018085.
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The easternmost part of the Mediterranean corresponds to a tectonically complex region which is linked with the convergence between Africa and Eurasia. The tectonostratigraphic evolution of this region is poorly constrained because of the absence of exploration wells. Cyprus is a crucial area to assess the link between the tectonic deformation and the consequent sedimentation in the Northern Levant margin. Paleogene and Neogene basins in the southern part of Cyprus record the main tectonic events related to the convergence of Africa and Eurasia. The objective of this contribution is to investigate the timing and the mechanisms of basin deformation, as well as the sedimentary infill of basins located onshore Cyprus and finally resolve how their evolution is linked to the regional geodynamic events. Based on fieldwork studies we reconstructed the tectono-stratigraphic evolution of the Polis Basin and the Limassol Basin to propose a conceptual model for the evolution of the Northern Levant margin, in accordance with the main geodynamic events. It is expected that analysis of the Polis and Limassol depressions, and later comparison of them will also shed more lights on the impact of the substratum and how it is associated to the main tectonic events.
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Duane, Michael J., and Roderick W. Brown. "Tectonic brines and sedimentary basins: further applications of fission track analysis in understanding Karoo Basin evolution (South Africa)." Basin Research 3, no. 4 (December 1991): 187–95. http://dx.doi.org/10.1111/j.1365-2117.1991.tb00128.x.
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Villeneuve, Michel, François Fournier, Simonetta Cirilli, Amalia Spina, Matar Ndiaye, Juste Zamba, Sophie Viseur, Jean Borgomano, and Papa Malik Ngom. "Structure of the Paleozoic basement in the Senegalo-Mauritanian basin (West Africa)." Bulletin de la Société Géologique de France 186, no. 2-3 (2015): 193–203. http://dx.doi.org/10.2113/gssgfbull.186.2-3.193.
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Abstract The interpretation of 2D seismic surveys from the Senegalo-Mauritanian basement and the reappraisal of rock-samples from oil exploration drillings provide new insights into the structure of the Appalachian-Mauritanian belts and the overlying Carboniferous and Permian basins. Two different units have been evidenced below the Mesozoic sedimentary cover : a lower unit (Unit 1 : basement) and an upper unit (Unit 2 : Late Palaeozoic basins). Unit 1 shows two distinct tectonic areas : the northern area with two different belts evidenced on both sides of the Senegalese block and the southern area exhibiting various tilted blocks making part of the Palaeozoic (Ordovician to Devonian) Bové basin. In the northern area the Western Thrust Belt is thrust over the Senegalese block while to the east, the so-called Mauritanian belt is thrusted over the West African craton. In the Mauritanian belt area, the youngest deformed sediments belonging to the outcropping Bove basin are Famennian in age. The Mauritanian inner belt underwent two tectono-metamorphic events (circa 330 and 270 Ma). Unit 2 which is unconformably capping both the Western Thrust Belt and the southern tilted blocks of the Paleozoic Bové basin (Casamance basin) is locally affected by eastward and westward-verging thrusts. Unit 2 is dated to the Early Permian by palynomorphs, and could have formed between the early (340–320 Ma) and late (270 Ma) Variscan tectonic events. The subsurface Late Palaeozoic basins from Senegal and Mauritania are interpreted as intra Variscan belt basins, similar to those suspected by seismic investigations off shore Guinea and Mauritania.
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Stone, Philip. "Geology reviewed for the Falkland Islands and their offshore sedimentary basins, South Atlantic Ocean." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 106, no. 2 (June 2015): 115–43. http://dx.doi.org/10.1017/s1755691016000049.
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ABSTRACTThe position of the Falkland Islands adjacent to the South American continental margin belies the close association of their geology with that of South Africa. A Mesoproterozoic basement is unconformably overlain by a Silurian to Devonian succession of fluvial to neritic and shallow marine, siliciclastic strata. This is disconformably succeeded by a largely Permian succession that, near its base, includes a glacigenic diamictite and, thence, passes upwards into a succession of deltaic and lacustrine strata. The lithological succession and the character of its deformation bear striking similarities to the Cape Fold Belt and Karoo retroarc foreland basin. Swarms of Early Jurassic dykes were coeval with the Karoo magmatism and the initial break-up of Gondwana; Early Cretaceous dykes were intruded during the opening of the South Atlantic Ocean. Offshore sedimentary basins surrounding the archipelago contain Late Jurassic to Palaeogene successions and are currently the focus of hydrocarbon exploration. Best known is the North Falkland Basin, a classic failed rift. To the SE, the passive margin, Falkland Plateau Basin may also be rift-controlled, whilst the South Falkland Basin is a foreland basin created at the boundary of the South American and Scotia plates. The role of the Falkland Islands during the breakup of Gondwana remains controversial. Compelling evidence from the onshore geology favours rotation of an independent microplate from an original position adjacent to the Eastern Cape, South Africa. Alternative interpretations, justified largely from offshore geology, favour extension of the Falkland Plateau as a fixed promontory from the South American margin.
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Smith, R. M. H., P. G. Eriksson, and W. J. Botha. "A review of the stratigraphy and sedimentary environments of the Karoo-aged basins of Southern Africa." Journal of African Earth Sciences (and the Middle East) 16, no. 1-2 (January 1993): 143–69. http://dx.doi.org/10.1016/0899-5362(93)90164-l.
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Amaral, Paula G. C., Mary Bernardes De Oliveira, Fresia Ricardi-Branco, and Jean Broutin. "Presencia de Bryopsida fértil en los niveles Westfalianos del subgrup Itararé, Cuenca de Paraná, Brasil." Bryophyte Diversity and Evolution 25, no. 1 (August 17, 2004): 101–10. http://dx.doi.org/10.11646/bde.25.1.12.
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The bryophyte fossils are rare, mainly in Paleozoic sedimentary rocks in spite of being present since the Silurian Period. In the Division Bryophyta, the fossils that belong to the Class Bryopsida are recognized since the Carboniferous, but they are extremely scarce. They are plentiful only in Permian sediments, in the Petchora, Kuznetsk and Russian Platform basins, also in Antarctica, Karoo basin (the last in South Africa) and India. Identified at the genus Dwykea, gametophyte specimens bearing pleurocarpous sporophyte were recovered from the lowermost levels of Itararé Subgroup, near Campinas city, S. Paulo State. These fossils correspond to the first register of bryophyte female gametophyte for the Carboniferous Period. The microflora in association with these fossils allow correlations of these levels to the Palynozone Ahrensisporites cristatus of Westphalian age. Related to proglacial sediments, they may correspond to a tundra vegetation covering the Northeastern border of Paraná Basin, during the Westphalian.
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Russell, James M., Dirk Verschuren, and Hilde Eggermont. "Spatial complexity of ‘Little Ice Age’ climate in East Africa: sedimentary records from two crater lake basins in western Uganda." Holocene 17, no. 2 (February 2007): 183–93. http://dx.doi.org/10.1177/0959683607075832.
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Griffis, N., I. Montañez, R. Mundil, D. Le Heron, P. Dietrich, C. Kettler, B. Linol, et al. "High-latitude ice and climate control on sediment supply across SW Gondwana during the late Carboniferous and early Permian." GSA Bulletin 133, no. 9-10 (February 1, 2021): 2113–24. http://dx.doi.org/10.1130/b35852.1.
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Abstract The response of sediment routing to climatic changes across icehouse-to-greenhouse turnovers is not well documented in Earth's pre-Cenozoic sedimentary record. Southwest Gondwana hosts one of the thickest and most laterally extensive records of Earth's penultimate icehouse, the late Paleozoic ice age. We present the first high-resolution U-Pb zircon chemical abrasion–isotope dilution–thermal ionization mass spectrometry (CA-ID-TIMS) analysis of late Paleozoic ice age deposits in the Kalahari Basin of southern Africa, which, coupled with existing CA-ID-TIMS zircon records from the Paraná and Karoo Basins, we used to refine the late Paleozoic ice age glacial history of SW Gondwana. Key findings from this work suggest that subglacial evidence in the Kalahari region is restricted to the Carboniferous (older than 300 Ma), with glacially influenced deposits culminating in this region by the earliest Permian (296 Ma). The U-Pb detrital zircon geochronologic records from the Paraná Basin of South America, which was located downstream of the Kalahari Basin in the latest Carboniferous and Permian, indicate that large-scale changes in sediment supplied to the Paraná were contemporaneous with shifts in the SW Gondwana ice record. Gondwanan deglaciation events were associated with the delivery of far-field, African-sourced sediments into the Paraná Basin. In contrast, Gondwanan glacial periods were associated with the restriction of African-sourced sediments into the basin. We interpret the influx of far-field sediments into the Paraná Basin as an expansion of the catchment area for the Paraná Basin during the deglaciation events, which occurred in the latest Carboniferous (300–299 Ma), early Permian (296 Ma), and late early Permian (<284 Ma). The coupled ice and detrital zircon records for this region of Gondwana present opportunities to investigate climate feedbacks associated with changes in freshwater and nutrient delivery to late Paleozoic ocean basins across the turnover from icehouse to greenhouse conditions.
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Augier, Romain, Laurent Jolivet, Damien Do couto, and François Negro. "From ductile to brittle, late- to post-orogenic evolution of the Betic Cordillera: Structural insights from the northeastern Internal zones." Bulletin de la Société Géologique de France 184, no. 4-5 (July 1, 2013): 405–25. http://dx.doi.org/10.2113/gssgfbull.184.4-5.405.
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Abstract Relations between Alpine detachment-bounded metamorphic domes, crustal-scale strike-slip fault zones and sedimentary basins in the Internal zones of the Betic cordillera are still matter of debate. Current tectonic interpretations of these basins vary from late-orogenic extensional structures to compressional ones associated with strike-slip motions along major still active faults. Structural investigations including new field mapping, meso-scale faults recognition, palaeostress analysis of brittle small-scale faults systems were performed in the sedimentary cover of the Almanzora corridor and the Huércal-Overa basins, located either in the hanging wall unit of the Filabres extensional shear zone or at the termination of the Alhama de Murcia sinistral fault zone. In parallel, a detailed study of the ductile and the ductile-brittle deformation was carried out in the footwall unit of the Filabres extensional shear zone, in the Nevado-Fílabride complex. Three main brittle events were recognised in the basin cover including two extensional events that occurred prior to a weak tectonic inversion of the basin during a third, still active event. The first one, D1b is characterized by the development a first stress regime consistent with ~NW-SE extensional tectonics. Besides, the consistency between the latest ductile and the brittle kinematics for the Filabres extensional shear zone and the activity of meso-scale fault systems that primarily control the main SW-NE depocentres allow concluding to a top-to-the-NW continuum of strain during the final exhumation of the Nevado-Filábride complex. The resulting overall half-graben architecture of the basins is then related to the combination of the formation of the metamorphic domes that added a local control superimposed on the regional deformation. Indeed, after a consistent top-to-the-west shearing prevailing during most of the Nevado-Filábride exhumation, final exhumation stages were in turn, characterised by important kinematics changes with a subordinate top-to-the-NW sense of shear (D1b). The onset of sedimentation in the basins occurred shortly after the crossing of the ductile-brittle transition in the underlying metamorphic domes at ca. 14 Ma into SW-NE fault-bounded troughs. Tectonic subsidence was then maintained during D2b while extensional kinematics changed to N-S or even locally to SSW-NNE. Extensional tectonics then lasted most of the Tortonian during the final tectonic denudation increments of the Sierra de los Filabres achieved at ca. 9-8 Ma. Intramontane basins are therefore genuinely extensional and clearly related to the latest exhumation stages of the Nevado-Filábride complex in the back-arc domain. Conversely, at ca. 8 Ma, basins started to record a ~N-S to NNW-SSE compressional stress regime (D3b) and ceased to be active depocentres while shortening within the Internal zones then recorded only the Iberia/Africa convergence. The weak inversion of the basins however resulted either in the reactivation of originally extensional faults such as the Alhama de Murcia fault or the basin individualisation and a progressive water exchange reduction with the Atlantic ocean and is thus proposed to be directly responsible for the Late Miocene salinity crises.
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Sissingh, W. "Kinematic sequence stratigraphy of the European Cenozoic Rift System and Alpine Foreland Basin: correlation with Mediterranean and Atlantic plate-boundary events." Netherlands Journal of Geosciences 85, no. 2 (June 2006): 77–129. http://dx.doi.org/10.1017/s0016774600077921.
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AbstractA review of the sequence stratigraphic development of the Tertiary basins of the North and West Alpine Foreland domains shows that their structural and depositional history was episodically affected by brief tectonic phases. These were associated with intermittent deformation events induced by the collisional convergence and compressional coupling of the Apulian and Iberian microplates with the European Plate. The plate kinematics-related episodicity was essentially isochronously recorded in the basin fills of the Alpine Foreland region. These are generally correlative with changes in eustatic sea level. The ensuing correlative successions of so-called Cenozoic Rift and Foredeep (CRF) sequences and phases can be traced throughout the European Cenozoic Rift System and Alpine Foreland Basin. Their temporal correlation indicates that, apparently, the changes in the plate collision-related stress regime of the Alpine Foreland were repeatedly accompanied by coeval changes in eustatic sea level. To test and substantiate the validity of this inferred causal relationship between intraplate deposition, plate kinematics and eustacy, the tectono-sedimentary evolution of the basins of the Mediterranean plate-boundary zone has been analysed in conjunction with a review of the plate-boundary events in the North Atlantic. Within the uncertainty range of available datings, synchroneity could thus be demonstrated for the punctuated tectonostratigraphic development of basins of the western Mediterranean (comprising the Liguro-Provençal Basin, Valencia Trough, Sardinia Rift and Tyrrhenian Basin), the Apenninic-Calabrian Arc, the Betic domain (including the Alboran Basin) and the North and West Alpine Foreland regions. Similar temporal correlations of plate tectonicsrelated events near the Mid-Atlantic Ridge in the North Atlantic and tectonostratigraphic sequences and phases of the Alpino-Pyrenean Foreland basins are further evidence of a common causal mechanism. The driving mechanisms appear to have been the northward drift of Africa and the resulting mechanical coupling of Apulia and Iberia with the southern passive margin of Europe, as well as the stepwise opening of the North Atlantic and accompanying episodic plate re-organisations of the Mid-Atlantic Ridge.
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Pouclet, André, Siaka Doumbia, and Max Vidal. "Geodynamic setting of the Birimian volcanism in central Ivory Coast (western Africa) and its place in the Palaeoproterozoic evolution of the Man Shield." Bulletin de la Société Géologique de France 177, no. 2 (March 1, 2006): 105–21. http://dx.doi.org/10.2113/gssgfbull.177.2.105.
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Abstract Palaeoproterozoic volcanic formations having different geochemical features are described in the Katiola-Marabadiassa area (Central Ivory Coast). They consist of (i) metamorphic mafic rocks belonging to the greenstone belts, (ii) rhyodacites intruded into the greenstone belts and interpreted as sub-volcanic apophyses of TTG plutons, and (iii) calc-alkaline andesitic lava interbedded in the lower sedimentary pile of the Bandama Basin. The greenstone belt rocks have a magmatic signature of ocean floor tholeiites. They were generated from moderate partial melting of a fairly depleted spinel lherzolite source. The rhyodacites show the same compositions as the TTG granitoids of the belt. These TTGs generated from melting of garnet-bearing amphibolite, derived from subducted oceanic crust, but also from peridotite melting of the fertilized mantle wedge. The andesites show a common composition of active continental margin potassic calc-alkaline lavas. However, they do not constitute a volcanic belt, but belong to an intracontinental basin settled in a wrench tectonic system. They probably generated from remelting of sub-crustal metasomatised mantle. The tectono-magmatism story of the Katiola-Marabadiassa area comprises four stages. A similar evolution is found in other belt-and-basin areas in Ivory Coast. A review of lithostratigraphic and chronological data of the Birimian terrains leads us to compare the four-stage model of the Central Ivory Coast to the West-African Palaeoproterozoic evolution. The first stage corresponds to ocean crust formation, by mid-ocean ridge accretion and volcanic arc building. The second stage, partly overlapping the previous one, is convergent and lasted from oceanic crust stacking to TTG and associated greenstone belt formation. It led to a protocontinental crust accretion by docking of granitized blocks, from ca 2200 Ma to 2110 Ma. The third stage corresponds to the formation of intracontinental basins by reorganization of the granitoid-greenstone shields and of the remnant oceanic basins, between 2118 Ma and 2093 Ma. It was associated with calc-alkaline magma production. The fourth stage is characterized by transtensional stress, with the closure of the basins by left-lateral wrenching along N-S faults, and by emplacement of new potassic granitoids until 2072 Ma.
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de Santana dos Anjos Zerfass, Geise, Dmitry A. Ruban, Farid Chemale Jr., and Henrique Zerfass. "Cenozoic synthem stratigraphic architecture of the SE Brazilian shelf and its global eustatic context: evidence from the Pelotas Basin (offshore Brazil)." Geologos 19, no. 4 (December 1, 2013): 273–90. http://dx.doi.org/10.2478/logos-2013-0018.
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Abstract The Pelotas Basin, located on the SE Brazilian shelf, has evolved since the Aptian. Stratigraphical data from the basin can be used for delineation of the unconformity-bounded units (synthems) on the shelf, which is a first step towards a full understanding of its stratigraphic architecture, evolution, and hydrocarbon potential. Hiatuses in the Cenozoic succession of the Pelotas Basin are established with both biostratigraphic (planktonic foraminifers and calcareous nannofossils) and isotopic (87Sr/86Sr) data. The seven recognised hiatuses are dated respectively as (1) Palaeocene (Danian- Thanetian), (2) Palaeocene/Eocene boundary (Thanetian-Ypresian), (3) Eocene (Ypresian-Lutetian), (4) Eocene-Oligocene (Lutetian-Rupelian), (5) early-late Oligocene (Rupelian-Chattian), (6) early Miocene (Aquitanian-Burdigalian), and (7) middle-late Miocene (Serravallian-Tortonian). These intervals between the hiatuses are correlated with those of the Santos and Campos Basins north from the Pelotas Basin. The breaks in sedimentation that these basins have in common occurred (1) at the Palaeocene-Eocene and (2) Eocene-Oligocene transitions, (3) in the early Miocene, and (4) in the middle-late Miocene. These main unconformities outline five synthems on the SE Brazilian shelf, viz. the SEBS-1 (Palaeocene), SEBS-2 (Eocene), SEBS-3 (Oligocene), SEBS-4 (early-middle Miocene) and SEBS-5 (late Miocene-Holocene). The above unconformities are correlated with those established in the Cenozoic sedimentary successions of different regions such as Western Siberia, Arabia, NW and NE Africa, peninsular India, S Australia, the Gulf of Mexico, NW Europe, and South Africa. The only regional unconformity, near the Oligocene/Miocene boundary, coincides with the nearly-global sedimentation break. The latter was resulted from a climatic event, i.e., the ‘Mi-1 glaciation’. Thus, a eustatic origin is supposed for this regional unconformity. The other regional unconformities also correspond to global sea-level falls (probably with an exception for the Palaeocene/Eocene surface), which suggests that global eustatic movements controlled the development of the regional synthem architecture.
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Guerrera, Francesco, and Manuel Martín-Martín. "Geodynamic events reconstructed in the Betic, Maghrebian, and Apennine chains (central-western Tethys)." Bulletin de la Société Géologique de France 185, no. 5 (May 1, 2014): 329–41. http://dx.doi.org/10.2113/gssgfbull.185.5.329.
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Abstract A synthetic study has been made to identify main tectono-sedimentary and geodynamic events in central-western Tethys. For this, an interdisciplinary analysis has been performed on successions belonging to tectonic units derived from Betic-Maghrebian-southern Apennine “Flysch basin” domain. The stratigraphic records of the internal, external, and mixed successions deposited in lateral basins of different chains show very similar characters, especially regarding: (a) lithostratigraphy and ages; (b) kind and provenance of supplies (immature and supermature petrofacies from internal and external margins, respectively); (c) presence of “mixed successions” (composed of alternating internal and external petrofacies) attesting to clear palaeogeographic relationships between opposite depositional systems; and (d) timing of the deformation. In addition, specific lithofacies reveal correspondence with similar sedimentary events, such as: (1) very thick silicoclastic supply concentrated in restricted time ranges indicating the main deformational phases in the margin/basin systems; (2) levels rich in black-shales, glauconian, siliceous-producers, and volcaniclastic intercalations, widespread in the studied successions and linked to particular events at the Tethyan scale (anoxic periods, starvation-upwelling, acid-intermediate penecontemporaneous volcanic activity, respectively). Tectonic influence has also been recorded by means of unconformities and tectofacies (such as turbidites, slumps, or olisthostromes, etc.), being correlated with the main deformational phases. Similar stratigraphic and tectonic events have also been found in the Calvana unit of Val Marecchia nappe (Ligurides, northern Apennine). Correlations of stratigraphic and tectonic events support the proposal of an evolutionary geodynamic model involving the presence of a “Mesomediterranean microplate” in intermediate position during Africa-Europe convergence. The closure of central-western Tethys occasioned the Betic-Maghrebian-southern Apennine oceanic branch deformation and the birth of perimediterranean chains during middle-late Miocene.
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Villeneuve, Michel, and Boris Marcaillou. "Pre-Mesozoic origin and paleogeography of blocks in the Caribbean, South Appalachian and West African domains and their impact on the post “variscan” evolution." Bulletin de la Société Géologique de France 184, no. 1-2 (January 1, 2013): 5–20. http://dx.doi.org/10.2113/gssgfbull.184.1-2.5.
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Abstract New geodynamical data from West Africa bring consistent informations on the pre-Mesozoic reconstruction within a large area running from the western Sahara to the Colombian cordillera. These new data support a Neoproterozoic Ocean (WANO) between the Amazonian (AMC) and West African (WAC) cratons previously to the Iapetus and Rheic oceans. We delineate 31 blocs detached from the surrounding three continents: NAC (North American Craton), AMC and WAC. 7 came from the WAC margin, 7 from the NAC, 6 from the AMC and 11 from an intermediate volcano sedimentary domain (COB) built on a 1200–1000 Ma oceanic crust. These imbricated blocks formed a tight mosaic by the Hercynian/Alleghanian tectonic event which gave way to the Pangea super-continent. But, during the Atlantic Ocean opening these blocks began to move. They were separated by new oceanic basins. However, previously to the Pangea, blocks from the COB domain formed two sets of garlands located on the northwestern Gondwana margin. The northern one moved to the North until the Silurian to collide the NAC (Taconic tectonic event) meanwhile the southern one remains on the Gondwana margin. All together were gathered by the Carboniferous/Permian time. Then, the framework for the opening of the Atlantic Ocean was not totally disconnected from the “Variscan” collage and many variscan weakness zones were re-used as initial breaking zones. Beyond this tectonic impact, the pre-mesozoic assemblage allows us to compare this “Caribbean” island arc with another one: the Indonesian “Banda” arc. Thus, West Africa is a geological key area for correlations between the Caribbean, the Appalachian, the Brazilian “Nordeste” and the West European domains and for the understanding of the Atlantic Ocean opening process.
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Spikings, Allan L., David M. Hodgson, Douglas A. Paton, and Yvonne T. Spychala. "Palinspastic restoration of an exhumed deepwater system: A workflow to improve paleogeographic reconstructions." Interpretation 3, no. 4 (November 1, 2015): SAA71—SAA87. http://dx.doi.org/10.1190/int-2015-0015.1.
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The Permian Laingsburg depocenter, Karoo Basin, South Africa, is the focus of sedimentological and stratigraphic research as an exhumed analog for offshore hydrocarbon reservoirs in deepwater basins. Thin-skinned thrust tectonics during the Permo-Triassic Cape Orogeny result in postdepositional deformation of the Permian basin fill. Regional-scale cross sections reveal two structural domains: a southern domain in the Laingsburg depocenter comprising 8–11-km wavelength north-verging fault-propagation folding, driven by buried low-angle ([Formula: see text]) reverse faults that coalesce at depth as part of a megadetachment below the Lower Paleozoic Cape Supergroup; and a northern domain to the north of the Laingsburg depocenter of short-wavelength, low-amplitude, asymmetrical folding facilitated by a detachment within the Permian Ecca Group. Five detailed structural cross sections permit the palinspastic restoration, and a calculation of the amount of shortening, across a [Formula: see text] area in the Laingsburg depocenter. Average shortening across the study area is −16.9% (5.8 km), and it decreases south to north. Shortening estimates from the Upper Ecca Group increase from 4.3 km near Matjiesfontein in the west to 10.4 km near Prince Albert in the east. Three-dimensional restorations of stratigraphic surfaces are consistent with these figures (−17%), and they allow paleogeographic and isopach thickness maps to be resorted to their configuration at the time of deposition. Structural restoration can be routinely used in outcrop studies to improve the accuracy of dimensions (e.g., volumetrics) and reconstructions (e.g., sediment dispersal patterns) derived from ancient sedimentary systems. The workflow presented here will add value to exhumed basin analogs by presenting prekinematic configurations at the frontal margins of fold-thrust belts.
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Le Roy, Pascal, Claire Gracia-Garay, Pol Guennoc, Jean-François Bourillet, Jean-Yves Reynaud, Isabelle Thinon, Patrick Kervevan, Fabien Paquet, David Menier, and Cédric Bulois. "Cenozoic tectonics of the Western Approaches Channel basins and its control of local drainage systems." Bulletin de la Société Géologique de France 182, no. 5 (September 1, 2011): 451–63. http://dx.doi.org/10.2113/gssgfbull.182.5.451.
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Abstract The geology of the Channel Western Approaches is a key to understand the post-rift evolution of the NW European continental margin in relation with the Europe/Africa collision. Despite considerable evidence of Tertiary tectonic inversion throughout the Channel basin, the structures and amplitudes of the tectonic movements remain poorly documented across the French sector of the Western Approaches. The effect of the tectonic inversion for the evolution of the “Channel River”, the major system that flowed into the English Channel during the Plio-Quaternary eustatic lowstands, also needs to be clarified. Its drainage basin was larger than the present-day English Channel and constituted the source of terrigenous fluxes of the Armorican and Celtic deep sea fans. A lack of high-resolution seismic data motivated the implementation of the GEOMOC and GEOBREST cruises, whose main results are presented in this paper. The new observations highlight the diachronism and the contrast in amplitudes of the deformations involved in the inversion of the French Western Approaches. The tectonic inversion can be described in two stages: a paroxysmal Paleogene stage including two episodes, Eocene (probably Ypresian) and Oligocene, and a more moderate Neogene stage subdivided into Miocene and Pliocene episodes, driven by the reactivation of the same faults. The deformations along the North Iroise fault (NIF) located at the termination of the Medio-Manche fault produced forced folds in the sedimentary cover above the deeper faults. The tectonic inversion generated uplift of about 700 m of the mid-continental shelf south of the NIF. The isochron map of the reflectors bounding the identified seismic sequences clearly demonstrates a major structural control on the geometry of the Neogene deposits. First, the uplift of the eastern part of the Iroise basin during the upper Miocene favoured the onset of a broad submarine delta system that developed towards the subsiding NW outer shelf. The later evolution of the ’palaeovalley’ network corresponding to the western termination of the “Channel River” exhibits a ’bayonet’ pattern marked by a zigzagging pattern of valleys, with alternating segments orientated N040oE and N070oE, controlled by Neogene faulting. The palaeovalley network could have begun during Reurevian or Pre-Tiglian sea-level lowstands, which exposed the entire shelf below the shelf edge. The amplitude of the sea-level fall is assumed to have been magnified by uplift of the Iroise basin, followed by later tilting of the outer shelf, as observed in many other examples documented along the North Atlantic margins.
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Ayodele, Irewole, Chiara Cavalleri, and Sarah Kabon. "Advanced logging and analytical methods unlock producibility potential in fresh formation water — A case study from offshore West Africa." Interpretation 4, no. 2 (May 1, 2016): SF113—SF123. http://dx.doi.org/10.1190/int-2015-0124.1.
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The sedimentary basins of West Africa encompass a vast diversity of geologic depositional settings, in and from which hydrocarbons are being explored and produced. The siliciclastic rock units can be structurally heterogeneous, the reservoirs distribution and quality is highly variable, and formation waters have changing salinity values. The fresh to very fresh formation water diminishes the contrast to hydrocarbon complicating any salinity-based measurement technique, such as resistivity. As a result, the reservoir potential might be under- or overestimated by conventional methods; hence, an intelligent petrophysical evaluation and a fit-to-purpose solution become essential to enable the most appropriate development and production strategy. As part of an extended portfolio of wireline logging technology, dielectric dispersion measurement is a critical contribution to the logging programs across the region. The advanced measurement provides dielectric permittivity and conductivity at multiple depths of investigation through the use of multiple frequencies, receiver spacing, and polarizations that are adequately fit into an innovative mandrel design. Robust inversion of all measurements enables solving for salinity, invasion profile, water fraction, shallow zone resistivity, and saturation even when it is hard to distinguish oil from freshwater. We have developed a remarkable example of intelligent logging assessment in highly complex reservoir units where the novel dielectric dispersion measurement is combined with high-resolution magnetic resonance for improved formation evaluation and reservoir management. An integrated data analysis workflow enables fast determination of pay zones and movable fluids independently from and to support saturation equation and input parameters setting. Comparison of the results from well testing confirms the improvement in reservoir description with additional advanced logging measurements (at an early stage of reservoir development) into reservoir models. The information provided is vital to guide perforation and completion designs.
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Pothier, Hayley D., John W. F. Waldron, Chris E. White, S. Andrew Dufrane, and Rebecca A. Jamieson. "Stratigraphy, provenance and tectonic setting of the Lumsden Dam and Bluestone Quarry formations (Lower Ordovician), Halifax Group, Nova Scotia, Canada." Atlantic Geology 51, no. 1 (February 15, 2015): 051. http://dx.doi.org/10.4138/atlgeol.2015.003.
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<p><span style="font-family: 'Minion Pro','serif'; font-size: 12pt; mso-fareast-font-family: Cambria; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-CA; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Cambrian to Ordovician metamorphosed clastic sedimentary rocks of the Meguma terrane have no correlatives elsewhere in Atlantic Canada but are similar to successions in North Wales. In the Meguma terrane, the Cambrian Goldenville Group, dominated by sandstone, is overlain by the Halifax Group, consisting mainly of fine-grained slate and siltstone. Within the Halifax Group widespread Furongian black slate units are overlain by greyer units with rare Early Ordovician fossils, assigned to the laterally equivalent Bear River, Feltzen, Bluestone Quarry, Lumsden Dam and Glen Brook formations. The type section of the Bluestone Quarry Formation, here defined, is on Halifax Peninsula, where four constituent members are recognized; the type section of the Lumsden Dam Formation is here defined in the Lumsden Dam region near Wolfville. Detrital zircons extracted from a sample of the Lumsden Dam Formation show a range of ages similar to those displayed by the underlying Goldenville Group, including abundant Neoproterozoic zircon representing Avalonian or Pan-African sources, and a prominent group of peaks between 1.95 and 2.2 Ga, probably representing sources in West Africa. A sample from the Glen Brook Formation east of Halifax shows a similar distribution. In contrast to the correlative Welsh successions, no influx of Mesoproterozoic zircon is seen in Early Ordovician samples, suggesting that, if the two basins were in close proximity in the Cambrian, they had diverged by the Early Ordovician, possibly as a result of strike-slip motion along the margin of Gondwana.</span></p>
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Robb, L. J., F. M. Meyer, C. J. Hawkesworth, and N. J. Gardiner. "Petrogenesis of Archaean granites in the Barberton region of South Africa as a guide to early crustal evolution." South African Journal of Geology 124, no. 1 (March 1, 2021): 111–40. http://dx.doi.org/10.25131/sajg.124.0021.
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ABSTRACT The Barberton region of South Africa is characterized by a broad variety of granite types that range in age from ca. 3.5 Ga to 2.7 Ga and reflect the processes involved in the formation of Archaean continental crust on the Kaapvaal Craton. These granites are subdivided into three groups, as follows: A tonalite-trondhjemite-granodiorite (TTG) suite diapirically emplaced at 3 450 Ma and 3 250 Ma into pre-existing metamorphosed greenstone belt material. TTG melts were derived from melting amphibolite in the lower crust, with individual plutons being emplaced at various crustal levels. The dome-and-keel geometry that characterizes the TTG-greenstone dominated crust at this time is inconsistent with a plate tectonic domain and reworking was likely controlled by gravity inversion or ‘sagduction’; Regionally extensive potassic batholiths (the GMS suite) were emplaced at 3 110 Ma during a period of crustal thickening and melting of a TTG-dominated lower crust. Subsequent to emplacement of the voluminous GMS granites, the thickened continental crust had stabilized sufficiently for large sedimentary basins to form; Late granite plutons were emplaced along two distinct linear and sub-parallel arrays close to what might have been the edge of a Kaapvaal continent at 2 800 to 2 700 Ma. They are subdivided into high-Ca and low-Ca granites that resemble the I- and S-type granites of younger orogenic episodes. The high-Ca granites are consistent with derivation from older granitoids in the lower crust, whereas the low-Ca granites may have been derived by melting metasedimentary precursors in the lower-mid crust. Granites with similar characteristics are associated with a subduction zone in younger terranes, although the recognition of such a feature at Barberton remains unclear. The petrogenesis of granites in the Barberton region between 3.5 Ga and 2.7 Ga provides a record of the processes of Archaean crustal evolution and contributes to discussions related to the onset of plate tectonics.
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Dietrich, Pierre, Fulvio Franchi, Larona Setlhabi, Rose Prevec, and Marion Bamford. "The nonglacial diamictite of Toutswemogala Hill (lower Karoo Supergroup, central Botswana): Implications on the extent of the late Paleozoic ice age in the Kalahari–Karoo Basin." Journal of Sedimentary Research 89, no. 10 (October 8, 2019): 875–89. http://dx.doi.org/10.2110/jsr.2019.48.
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ABSTRACT Along the easternmost edge of the Karoo–Kalahari Basin (KKB) of Botswana, the Toutswemogala Hill succession exposes a 30–50-m-thick suite of siliciclastic deposits interpreted by some as glaciogenic in origin tied to the Permo-Carboniferous Late Paleozoic Ice Age (LPIA). Six facies associations (FA) were recognized in this succession, resting unconformably on a highly uneven Archean gneissic basement, and consisting from base to top of: 1) clast-supported breccia made up of angular cobbles and boulders ubiquitously derived from the underlying basement, 2) well-bedded siltstones sealing or locally interdigitated with the underlying breccia, and bearing abundant remnants of Glossopteris sp. leaves, 3) a chaotic to faintly laminated matrix-supported diamictite bearing angular and subrounded clasts and tree logs attributed to the genus Megaporoxylon, 4) cross-bedded conglomerate bearing well-rounded quartz and clasts, 5) planar-laminated to ripple-laminated, poorly sorted, muddy sandstones showcasing dispersed mud chips that grade upward into 6) poorly sorted, cross-bedded coarse-grained sandstones displaying convolute beds and abundant imprints of unidentifiable tree logs. No evidence of glaciogenic processes have been found in this succession, in the form of either pavement or clasts striations. The breccia and diamictite are interpreted as scree and mass-flow deposits, respectively. Along with the age of the deposits, inferred from the plant debris (upper Carboniferous to lower Permian), the stratigraphic position of this sedimentary succession resting on the Archean basement suggests that it corresponds to the Dukwi Formation, a stratigraphic equivalent of the Dwyka Group in the Main Karoo Basin. This would explain the resemblance of the facies to those recovered at the base of the central Kalahari–Karoo Basin and in the neighboring Tuli, Ellisras, and Tshipise basins. The absence of diagnostic criteria for glacial processes in the studied succession raises the question of the extent, in both time and space, of the LPIA-related ice masses over southern Africa and particularly in southeastern Botswana. It is suggested here that during this glacial epoch, spatially restricted ice masses were confined in bedrock valleys (valley glaciers) in an uplifted setting otherwise characterized by non-glaciogenic processes, further strengthening the scenario of fragmented ice masses over southern Gondwana.
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Fatti, Jan L., George C. Smith, Peter J. Vail, Peter J. Strauss, and Philip R. Levitt. "Detection of gas in sandstone reservoirs using AVO analysis: A 3-D seismic case history using the Geostack technique." GEOPHYSICS 59, no. 9 (September 1994): 1362–76. http://dx.doi.org/10.1190/1.1443695.
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The Geostack technique is a method of analyzing seismic amplitude variation with offset (AVO) information. One of the outputs of the analysis is a set of direct hydrocarbon indicator traces called “fluid factor” traces. The fluid factor trace is designed to be low amplitude for all reflectors in a clastic sedimentary sequence except for rocks that lie off the (mudrock line.) The mudrock line is the line on a crossplot of P‐wave velocity against S‐wave velocity on which water‐saturated sandstones, shales, and siltstones lie. Some of the rock types that lie off the mudrock line are gas‐saturated sandstones, carbonates, and igneous rocks. In the absence of carbonates and igneous rocks, high amplitude reflections on fluid factor traces would be expected to represent gas‐saturated sandstones. Of course, this relationship does not apply exactly in nature, and the extent to which the mudrock line model applies varies from area to area. However, it is a useful model in many basins of the world, including the one studied here. Geostack processing has been done on a 3-D seismic data set over the Mossel Bay gas field on the southern continental shelf of South Africa. We found that anomalously high amplitude fluid factor reflections occurred at the top and base of the gas‐reservoir sandstone. Maps were made of the amplitude of these fluid factor reflections, and it was found that the high amplitude values were restricted mainly to the gas field area as determined by drilling. The highest amplitudes were found to be located roughly in the areas of best reservoir quality (i.e., highest porosity) in areas where the reservoir is relatively thick.
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Magalhães, José Ricardo, José Antonio Barbosa, Jefferson Tavares C. Oliveira, and Mário F. de Lima Filho. "CHARACTERIZATION OF THE OCEAN-CONTINENT TRANSITION IN THE PARAÍBA BASIN AND NATAL PLATFORM REGION, NE BRAZIL." Revista Brasileira de Geofísica 32, no. 3 (September 1, 2014): 481. http://dx.doi.org/10.22564/rbgf.v32i3.504.
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ABSTRACT. Several studies have tried to address the evolution of the Atlantic conjugate margins, including Brazil and West Africa. However, past researchadvances has been hindered by a lack of data for the marginal region in the eastern portion of northeastern Brazil, extending from the Pernambuco Shear Zone tothe Touros High. This situation has imposed serious limitations on the development of a regional view of the paleotectonic and paleogeographic evolution of the marginin this area and on correlations with regional counterparts in Africa. Here, we present an investigation using regional seismic and potential field data. The results showthat this region represents a basement high forming a narrow platform with a thin sedimentary cover (0.8-2.5 km) and an abrupt shelf break, which created a large bypasszone towards the slope. The analysis of a deep seismic section revealed that thinned continental crust (transitional crust) occupies a narrow zone and that the continentaloceanicboundary (COB) is located approximately 100 km to the east of the present coastline. Geophysical modeling integrated with interpretation of the seismic datasuggests that this region is characterized by an abrupt thinning of continental crust, with an accompanying sudden rise of the Moho. There are also indications for theexistence of a zone of extremely thinned continental crust, which was interpreted as proto-oceanic crust. Our findings suggest that the study area shows strong similaritiesto non-volcanic rifted margins.Keywords: Paraíba and Natal Platform Basins, continental-oceanic transition, northeastern Brazilian continental margin, Atlantic rift. RESUMO. Vários trabalhos têm tentado abordar a evolução das margens conjugadas do Atlântico, incluindo o nordeste do Brasil e o oeste da África. Entretanto,o avanço de pesquisas anteriores tem sido dificultado em razão da falta de dados na região marginal da porção oriental do nordeste do Brasil, a área entre a Zonade Cisalhamento de Pernambuco e o Alto de Touros. Este fato tem imposto limitações ao desenvolvimento de modelos regionais sobre a evolução paleotectônica e paleogeográfica desta região, assim como na correlação com sua contraparte na África. Aqui é apresentada uma investigação realizada com base em dados sísmicos e de métodos potenciais regionais. Os resultados mostraram que esta região representa um alto do embasamento que forma uma plataforma estreita com uma coberturasedimentar pouco espessa (0,8-2,5 km) e uma quebra abrupta da plataforma, o que criou uma grande zona de by pass através do talude. A análise de uma seçao sísmica profunda revelou que a crosta continental afinada (crosta transicional) representa uma estreita zona, e que o limite crosta continental-oceânica (COB) está localizadoa aproximadamente 100 km a leste da atual linha de costa. A modelagem geofísica, integrada com a interpretação sísmica, indica que esta região é caracterizada porum afinamento abrupto da crosta continental, com a consequente ascensão súbita da Moho. Também há evidências da existência de uma zona de crosta continental extremamente afinada, a qual foi interpretada como crosta proto-oceânica. Estes novos dados demonstram que esta área apresenta fortes similaridades com margens rifteadas não vulcânicas.Palavras-chave: bacias da Paraíba e da Plataforma de Natal, transição crosta continental-oceânica, margem continental do nordeste Brasileiro, rifte Atlântico.
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Ballo, M. B., T. V. Karaseva, and A. S. Kapitanova. "Features of the Geological Structure of the African Sedimentary Basin Taoudeni and its Oil-and-Gas Potential." Вестник Пермского университета. Геология 19, no. 4 (2020): 388–95. http://dx.doi.org/10.17072/psu.geol.19.4.388.
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The results of studying the structure of the Taoudeni sedimentary basin, the largest basin in north-west Africa, are presented. The characteristic features of the basin associated with the development of the West African craton, and manifestation of the Hercynian and Alpine tectonogenesis are revealed. Based on modeling data, the low rates of sedimentation of Proterozoic and Silurian-Carboniferous sediments were established that contributed to the formation of oil-and-gas source rocks. It is concluded that it is necessary to continue exploration in the basin in connection with the high prospects of oil-and-gas potential.
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Green, Paul F., Karna Lidmar-Bergström, Peter Japsen, Johan M. Bonow, and James A. Chalmers. "Stratigraphic landscape analysis, thermochronology and the episodic development of elevated, passive continental margins." Geological Survey of Denmark and Greenland (GEUS) Bulletin 30 (December 30, 2013): 1–150. http://dx.doi.org/10.34194/geusb.v30.4673.
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The continental margin of West Greenland is similar in many respects to other elevated, passive continental margins (EPCMs) around the world. These margins are characterised by extensive regions of low relief at elevations of 1–2 kilometres above sea level sloping gently inland, with a much steeper, oceanward decline, often termed a 'Great Escarpment', terminating at a coastal plain. Recent studies, based on integration of geological, geomorphological and thermochronological evidence, have shown that the high topography of West Greenland was formed by differential uplift and dissection of an Oligo-Miocene peneplain since the late Miocene, many millions of years after continental break-up between Greenland and North America. In contrast, many studies of other EPCMs have proposed a different style of development in which the high plateaux and the steep, oceanward decline are regarded as a direct result of rifting and continental separation. Some studies assume that the elevated regions have remained high since break-up, with the high topography continuously renewed by isostasy. Others identify the elevated plains as remnants of pre-rift landscapes. Key to understanding the development of the West Greenland margin is a new approach to the study of landforms, stratigraphic landscape analysis, in which the low-relief, high-elevation plateaux at EPCMs are interpreted as uplifted peneplains: low-relief surfaces of large extent, cutting across bedrock of different age and resistance, and originally graded to sea level. Identification of different generations of peneplain (re-exposed and epigene) from regional mapping, combined with geological constraints and thermochronology, allows definition of the evolution leading to the formation of the modern-day topography. This approach is founded particularly on results from the South Swedish Dome, which document former sea levels as base levels for the formation of peneplains. These results support the view that peneplains grade towards base level, and that in the absence of other options (e.g. widespread resistant lithologies), the most likely base level is sea level. This is particularly so at continental margins due to their proximity to the adjacent ocean. Studies in which EPCMs are interpreted as related to rifting or break-up commonly favour histories involving continuous denudation of margins following rifting, and interpretation of thermochronology data in terms of monotonic cooling histories. However, in several regions, including southern Africa, south-east Australia and eastern Brazil, geological constraints demonstrate that such scenarios are inappropriate, and an episodic development involving post-breakup subsidence and burial followed later by uplift and denudation is more realistic. Such development is also indicated by the presence in sedimentary basins adjacent to many EPCMs of major erosional unconformities within the post-breakup sedimentary section which correlate with onshore denudation episodes. The nature of the processes responsible is not yet understood, but it seems likely that plate-scale forces are required in order to explain the regional extent of the effects involved. New geodynamic models are required to explain the episodic development of EPCMs, accommodating post-breakup subsidence and burial as well as subsequent uplift and denudation, long after break-up which created the characteristic, modern-day EPCM landscapes.
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Ndip, Edwin Ayuk, Agyingi CM, Nton ME, and Oladunjoye MA. "Review of the geology of mamfe sedimentary basin, SW Cameroon, Central Africa." Journal of Oil, Gas and Petrochemical Sciences 1, no. 1 (March 23, 2018): 35–40. http://dx.doi.org/10.30881/jogps.00008.
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Zamil, M. Sh. "A possible model of the Paleozoic sedimentary basins evolution at the North African platform." Proceedings of higher educational establishments. Geology and Exploration, no. 6 (December 28, 2017): 68–73. http://dx.doi.org/10.32454/0016-7762-2017-6-68-73.
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A dual model of the Paleozoic basins development, disposing on the Late Proterozoic (Pan-African) and the Early Proterozoic (Eburnean) crust, has been proposed. The formation of the first group basins is connected with the subsiding of the sections of the cooling gneissic-domes of«rejuvenated» (Early Precambrian but tectonically reworked at the end of the Proterozoic) Pan-African crust. Accordingly, the development of the second group basins is a result of the Precambrian deep sited (mantle) magmatic chambers cooling and subsiding together with the sites of the old lithosphere, covering them. The manifestation of the Vendian volcanic units on Anti-Atlas, Ugarta, Regibat-Eglab uplifts is the most possible evidence of the mantle magmatic activity, which could create those chambers.
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Agyemang, Prince C. Owusu, Eric M. Roberts, Bob Downie, and Joseph J. W. Sertich. "Sedimentary provenance and maximum depositional age analysis of the Cretaceous? Lapur and Muruanachok sandstones (Turkana Grits), Turkana Basin, Kenya." Geological Magazine 156, no. 08 (December 3, 2018): 1334–56. http://dx.doi.org/10.1017/s0016756818000663.
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AbstractThe Turkana Basin of northwestern Kenya is well known for its rich Neogene–Quaternary vertebrate fossil record; however, it also represents one of the few locations in sub-Saharan Africa where Cretaceous vertebrate fossils, including dinosaurs and other archosaurs, are preserved. These Cretaceous deposits are colloquially referred to as the ‘Turkana Grits’, and assumed to be Cretaceous in age based on their limited biostratigraphy. The ‘Turkana Grits’ are overlain by Palaeogene volcanic rocks (<35 Ma), which are widely considered to record the earliest evidence of plume-related volcanism in the East African Rift System. In this study, we present the results of an integrated sedimentary provenance investigation of two units within the ‘Turkana Grits’ called the Lapur and Muruanachok sandstones. Analysis of U–Pb ages and Lu–Hf initial ɛHf(t) values from 1106 detrital zircons demonstrate that sediments are primarily derived from Neoarchaean and Neoproterozoic basement sources, except for six Palaeogene grains from the upper Lapur Sandstone, which are of unknown provenance. Considered together, these data point to the Mozambique Belt, which makes up the nearby rift flanks, as the primary provenance source. This is consistent with palaeocurrent data, and suggests localized sediment input by alluvial fans, which fed into NNW-directed fluvial systems. Perhaps the most surprising finding is the identification of the late Paleocene detrital zircons, which not only demonstrate that the depositional age for the top of the formation is Paleocene rather than Cretaceous, but also provides possible evidence for the oldest Palaeogene volcanic activity within the East African Rift System.
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Le Pichon, Xavier, Claude Rangin, Youri Hamon, Nicolas Loget, Jin Ying Lin, Louis Andreani, and Nicolas Flotte. "Geodynamics of the France Southeast Basin." Bulletin de la Société Géologique de France 181, no. 6 (November 1, 2010): 477–501. http://dx.doi.org/10.2113/gssgfbull.181.6.477.
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AbstractWe investigate the geodynamics of the Southeast Basin with the help of maps of the basement and of major sedimentary horizons based on available seismic reflection profiles and drill holes. We also present a study of the seismicity along the Middle Durance fault. The present seismic activity of the SE Basin cannot be attributed to the Africa/Eurasia shortening since spatial geodesy demonstrates that there is no significant motion of Corsica-Sardinia with respect to Eurasia and since gravitational collapse of the Alps has characterized the last few millions years. Our study demonstrates that the basement of this 140 by 200 km Triassic basin has been essentially undeformed since its formation, most probably because of the hardening of the cooling lithosphere after its 50% thinning during the Triassic distension. The regional geodynamics are thus dominated by the interaction of this rigid unit with the surrounding zones of active deformation. The 12 km thick Mesozoic sediment cover includes at its base an up to 4 km thick mostly evaporitic Triassic layer that is hot and consequently highly fluid. The sedimentary cover is thus decoupled from the basement. As a result, the sedimentary cover does not have enough strength to produce reliefs exceeding about 500 to 750 m. That the deformation and seismicity affecting the basin are the results of cover tectonics is confirmed by the fact that seismic activity in the basin only affects the sedimentary cover. Based on our mapping of the structure of the basin, we propose a simple mechanism accounting for the Neogene deformation of the sedimentary cover. The formation of the higher Alps has first resulted to the north in the shortening of the Diois-Baronnies sedimentary cover that elevated the top of Jurassic horizons by about 4 km with respect to surrounding areas to the south and west. There was thus passage from a brittle-ductile basement decollement within the higher Alps to an evaporitic decollement within the Diois-Baronnies. This shortening and consequent elevation finally induced the southward motion of the basin cover south of the Lure mountain during and after the Middle Miocene. This southward motion was absorbed by the formation of the Luberon and Trévaresse mountains to the south. To the east of the Durance fault, there is no large sediment cover. The seismicity there, is related to the absorption of the Alps collapse within the basement itself. To the west of the Salon-Cavaillon fault, on the other hand, gravity induces a NNE motion of the sedimentary cover with extension to the south and shortening to the north near Mont Ventoux. When considering the seismicity of this area, it is thus important to distinguish between the western Basin panel, west of the Salon-Cavaillon fault affected by very slow NNE gliding of the sedimentary cover, with extension to the south and shortening to the north; the central Basin panel west of the Durance fault with S gliding of the sedimentary cover and increasing shortening to the south; and finally the basement panel east of the Durance fault with intrabasement absorption of the Alps collapse through strike-slip and thrust faults.
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LEPRÊTRE, R., J. BARBARAND, Y. MISSENARD, F. LEPARMENTIER, and D. FRIZON DE LAMOTTE. "Vertical movements along the northern border of the West African Craton: the Reguibat Shield and adjacent basins." Geological Magazine 151, no. 5 (November 13, 2013): 885–98. http://dx.doi.org/10.1017/s0016756813000939.
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AbstractThe absence of a sedimentary record on large cratonic areas often prevents the reconstruction of the history of their vertical movements. The Reguibat Rise, belonging to the West African Craton, is typically a large basement high, whose Meso-Cenozoic history is poorly known because of the extreme reduction of this sedimentary record. In this paper we present the first thermochronological data from the centre of the Reguibat Rise, and combine them with the geometry of the sedimentary formations in the adjoining Tindouf and Taoudeni basins situated north and south, respectively. Fission track analysis on apatite yields ages from 256±21 Ma to 139±8 Ma, and 120±10 Ma by (U–Th)/He dating. Two competing scenarios are tested based on these data with thermal history modelling. We favour the scenario that includes a Late Jurassic/Early Cretaceous cooling of the samples, based on stratigraphical constraints and the thermochronological results. We then propose a new model for the evolution of this region and reveal the occurrence of a previously unknown major exhumation event at the Jurassic/Cretaceous transition accounting for the main present-day structures.
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Piana Agostinetti, Nicola, Francesca Martini, and Joe Mongan. "Sedimentary basin investigation using receiver function: an East African Rift case study." Geophysical Journal International 215, no. 3 (October 2, 2018): 2105–13. http://dx.doi.org/10.1093/gji/ggy405.
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SUMMARY We apply receiver function (RF) methodology to map the geometry of a sedimentary basin along a ∼10-km-long profile of broadband seismometers that recorded continuously for approximately 3 months. For a subset of the stations, we apply the Neighbourhood Algorithm inversion scheme, to quantify the geometry of basin bounding fault directly beneath the stations. We compare our results with active reflection seismic data and with the lithostratigraphy from a well located along the profile. We find that the P-to-s conversions from the sediments–basement interface (SBI), recorded in RF data sets together with information on intrabasin structures, are useful for obtaining high resolution images of the basin. The depth of the SBI derived from RF inversion is consistent (within ∼0.4 km) with the estimates from active reflection seismic and the well data. This study highlights that analysis of teleseismic waveforms can retrieve relevant information on the structure of a sedimentary basin.
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Cairncross, B. "Tectono-sedimentary settings and controls of the Karoo Basin Permian coals, South Africa." International Journal of Coal Geology 16, no. 1-3 (December 1990): 175–78. http://dx.doi.org/10.1016/0166-5162(90)90031-s.
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Ndikum, Eric N., Charles T. Tabod, F. Koumetio, Noutchogwe C. Tatchum, and Kenfack J. Victor. "Evidence of Some Major Structures Underlying the Douala Sedimentary Sub-Basin: West African Coastal Basin." Journal of Geoscience and Environment Protection 05, no. 07 (2017): 161–72. http://dx.doi.org/10.4236/gep.2017.57013.
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Fekkak, Abdelilah, André Pouclet, and Lakhlifi Badra. "The Pre-Pan-African rifting of Saghro (Anti-Atlas, Morocco): example of the middle Neoproterozoic Basin of Boumalne." Bulletin de la Société Géologique de France 173, no. 1 (January 1, 2002): 25–35. http://dx.doi.org/10.2113/173.1.25.
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Abstract In the Anti-Atlas, the Boumalne basin includes 3,000 m of Middle Neoproterozoic sediments. It consists of turbiditic deposits folded during the major Pan-African event ca 685 Ma. A syn-sedimentary basaltic pile of lava flows is interbedded in the upper part of the lower formation. These lavas show an initial rift tholeiite (IRT) chemical signature. Petrographical analysis of sediments and typology of detrital zircons indicate a continental margin sedimentation, without any volcano-sedimentary supply from a close volcanic arc. It is concluded that the Boumalne Basin formed in a continental passive margin evolving from an intracontinental rift. This interpretation differs clearly from that of a back-arc basin which is commonly accepted. Hence, the opening of this basin is related to the pre-Pan-African Saghro rift synchronous to the Central Anti-Atlas oceanization, and not to the demise of this oceanic domain along an active margin.
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Nave, Sı́lvia, Emı́lia Salgueiro, and Fátima Abrantes. "Siliceous sedimentary record of the last 280 kyr in the Canary basin (NW Africa)." Marine Geology 196, no. 1-2 (April 2003): 21–35. http://dx.doi.org/10.1016/s0025-3227(03)00045-8.
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Smith, R. M. H. "A review of stratigraphy and sedimentary environments of the Karoo Basin of South Africa." Journal of African Earth Sciences (and the Middle East) 10, no. 1-2 (1990): 117–37. http://dx.doi.org/10.1016/0899-5362(90)90050-o.
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Cuney, Michel. "Felsic magmatism and uranium deposits." Bulletin de la Société Géologique de France 185, no. 2 (February 1, 2014): 75–92. http://dx.doi.org/10.2113/gssgfbull.185.2.75.
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Abstract The strongly incompatible behaviour of uranium in silicate magmas results in its concentration in the most felsic melts and a prevalence of granites and rhyolites as primary U sources for the formation of U deposits. Despite its incompatible behavior, U deposits resulting directly from magmatic processes are quite rare. In most deposits, U is mobilized by hydrothermal fluids or ground water well after the emplacement of the igneous rocks. Of the broad range of granite types, only a few have U contents and physico-chemical properties that permit the crystallization of accessory minerals from which uranium can be leached for the formation of U deposits. The first granites on Earth, which crystallized uraninite, dated at 3.1 Ga, are the potassic granites from the Kaapval craton (South Africa) which were also the source of the detrital uraninite for the Dominion Reef and Witwatersrand quartz pebble conglomerate deposits. Four types of granites or rhyolites can be sufficiently enriched in U to represent a significant source for the genesis of U deposits: peralkaline, high-K metaluminous calc-alkaline, L-type peraluminous and anatectic pegmatoids. L-type peraluminous plutonic rocks in which U is dominantly hosted in uraninite or in the glass of their volcanic equivalents represent the best U source. Peralkaline granites or syenites are associated with the only magmatic U-deposits formed by extreme fractional crystallization. The refractory character of the U-bearing minerals does not permit their extraction under the present economic conditions and make them unfavorable U sources for other deposit types. By contrast, felsic peralkaline volcanic rocks, in which U is dominantly hosted in the glassy matrix, represent an excellent source for many deposit types. High-K calc-alkaline plutonic rocks only represent a significant U source when the U-bearing accessory minerals (U-thorite, allanite, Nb oxides) become metamict. The volcanic rocks of the same geochemistry may be also a favorable uranium source if a large part of the U is hosted in the glassy matrix. The largest U deposit in the world, Olympic Dam in South Australia is hosted by highly fractionated high-K plutonic and volcanic rocks, but the origin of the U mineralization is still unclear. Anatectic pegmatoids containing disseminated uraninite which results from the partial melting of uranium-rich metasediments and/or metavolcanic felsic rocks, host large low grade U deposits such as the Rössing and Husab deposits in Namibia. The evaluation of the potentiality for igneous rocks to represent an efficient U source represents a critical step to consider during the early stages of exploration for most U deposit types. In particular a wider use of the magmatic inclusions to determine the parent magma chemistry and its U content is of utmost interest to evaluate the U source potential of sedimentary basins that contain felsic volcanic acidic tuffs.
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Lafosse, Manfred, Elia d'Acremont, Alain Rabaute, Ferran Estrada, Martin Jollivet-Castelot, Juan Tomas Vazquez, Jesus Galindo-Zaldivar, et al. "Plio-Quaternary tectonic evolution of the southern margin of the Alboran Basin (Western Mediterranean)." Solid Earth 11, no. 2 (April 30, 2020): 741–65. http://dx.doi.org/10.5194/se-11-741-2020.
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Abstract. Progress in the understanding and dating of the sedimentary record of the Alboran Basin allows us to propose a model of its tectonic evolution since the Pliocene. After a period of extension, the Alboran Basin underwent a progressive tectonic inversion starting around 9–7.5 Ma. The Alboran Ridge is a NE–SW transpressive structure accommodating the shortening in the basin. We mapped its southwestern termination, a Pliocene rhombic structure exhibiting series of folds and thrusts. The active Al-Idrissi Fault zone (AIF) is a Pleistocene strike-slip structure trending NNE–SSW. The AIF crosses the Alboran Ridge and connects to the transtensive Nekor Basin and the Nekor Fault to the south. In the Moroccan shelf and at the edge of a submerged volcano we dated the inception of the local subsidence at 1.81–1.12 Ma. The subsidence marks the propagation of the AIF toward the Nekor Basin. Pliocene thrusts and folds and Quaternary transtension appear at first sight to act at different tectonic periods but reflect the long-term evolution of a transpressive system. Despite the constant direction of Africa–Eurasia convergence since 6 Ma, along the southern margin of the Alboran Basin, the Pliocene–Quaternary compression evolves from transpressive to transtensive along the AIF and the Nekor Basin. This system reflects the logical evolution of the deformation of the Alboran Basin under the indentation of the African lithosphere.
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Sami, K. "Recharge mechanisms and geochemical processes in a semi-arid sedimentary basin, Eastern Cape, South Africa." Journal of Hydrology 139, no. 1-4 (November 1992): 27–48. http://dx.doi.org/10.1016/0022-1694(92)90193-y.
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van der Merwe, W. C., D. M. Hodgson, and S. S. Flint. "Widespread syn-sedimentary deformation on a muddy deep-water basin-floor: the Vischkuil Formation (Permian), Karoo Basin, South Africa." Basin Research 21, no. 4 (August 2009): 389–406. http://dx.doi.org/10.1111/j.1365-2117.2009.00396.x.
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Soto-Kerans, Graham M., Daniel F. Stockli, Xavier Janson, Timothy F. Lawton, and Jacob A. Covault. "Orogen proximal sedimentation in the Permian foreland basin." Geosphere 16, no. 2 (January 6, 2020): 567–93. http://dx.doi.org/10.1130/ges02108.1.
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Abstract The sedimentary fill of peripheral foreland basins has the potential to preserve a record of the processes of ocean closure and continental collision, as well as the long-term (i.e., 107–108 yr) sediment-routing evolution associated with these processes; however, the detrital record of these deep-time tectonic processes and the sedimentary response have rarely been documented during the final stages of supercontinent assembly. The stratigraphy within the southern margin of the Delaware Basin and Marathon fold and thrust belt preserves a record of the Carboniferous–Permian Pangean continental assembly, culminating in the formation of the Delaware and Midland foreland basins of North America. Here, we use 1721 new detrital zircon (DZ) U-Pb ages from 13 stratigraphic samples within the Marathon fold and thrust belt and Glass Mountains of West Texas in order to evaluate the provenance and sediment-routing evolution of the southern, orogen-proximal region of this foreland basin system. Among these new DZ data, 85 core-rim age relationships record multi-stage crystallization related to magmatic or metamorphic events in sediment source areas, further constraining source terranes and sediment routing. Within samples, a lack of Neoproterozoic–Cambrian zircon grains in the pre-orogenic Mississippian Tesnus Formation and subsequent appearance of this zircon age group in the syn-orogenic Pennsylvanian Haymond Formation point toward initial basin inversion and the uplift and exhumation of volcanic units related to Rodinian rifting. Moreover, an upsection decrease in Grenvillian (ca. 1300–920 Ma) and an increase in Paleozoic zircons denote a progressive provenance shift from that of dominantly orogenic highland sources to that of sediment sources deeper in the Gondwanan hinterland during tectonic stabilization. Detrital zircon core-rim age relationships of ca. 1770 Ma cores with ca. 600–300 Ma rims indicate Amazonian cores with peri-Gondwanan or Pan-African rims, Grenvillian cores with ca. 580 Ma rims are correlative with Pan-African volcanism or the ca. 780–560 Ma volcanics along the rifted Laurentian margin, and Paleozoic core-rim age relationships are likely indicative of volcanic arc activity within peri-Gondwana, Coahuila, or Oaxaquia. Our results suggest dominant sediment delivery to the Marathon region from the nearby southern orogenic highland; less sediment was delivered from the axial portion of the Ouachita or Appalachian regions suggesting that this area of the basin was not affected by a transcontinental drainage. The provenance evolution of sediment provides insights into how continental collision directs the dispersal and deposition of sediment in the Permian Basin and analogous foreland basins.
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Hicks, N., D. J. C. Gold, M. Ncume, and L. Hoyer. "A new lithostratigraphic framework and unified nomenclature for the Nsuze Group of the Nkandla sub-basin, southern Kaapvaal Craton, South Africa." South African Journal of Geology 124, no. 3 (September 1, 2021): 699–716. http://dx.doi.org/10.25131/sajg.124.0027.
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Abstract During the early 20th century the term Insuzi Series, later reclassified as the Nsuze Group of the Pongola Supergroup, was proposed for a volcano-sedimentary succession exposed in the upper Nsuze River valley in central KwaZulu-Natal, South Africa. Subsequently, however, there has been little consensus on lithostratigraphic frameworks within the type area, and limited correlation with the exceptionally well-defined stratigraphy within the main Pongola basin. Recent mapping, combined with newly acquired high-resolution aeromagnetic data, satellite imagery, and available published geochronological data suggest that previously published schemes within the Nkandla sub-basin require revision. Utilising important regional marker units, as well as the stratigraphic positions of distinct sedimentary facies within the otherwise volcanic Nsuze Group, a working model is proposed. Lithostratigraphic units are well represented in the Mhlatuze and Nkandla inliers with examples from these areas given prominence. Where exposed, potential correlates within the Nsuze nappe complex are discussed. Within the proposed scheme the siliciclastic Mantonga Formation forms the base of the Nsuze Group, nonconformably overlying basement granitoids of the Kaapvaal Craton within the Mhaltuze Inlier. Mafic volcanics of the Nhlebela Formation overlie the Mantonga Formation in the inlier. These two lower units are, however, not exposed elsewhere in the sub-basin. The sedimentary White Mfolozi Formation forms the base of the succession in the Nkandla Inlier. Diamictites and stromatolite-bearing carbonate lithologies unique to this unit are utilised for regional third-order correlations with the type-area in the White Mfolozi Inlier. Mafic volcanics of the Agatha Formation overlie the White Mfolozi Formation in all exposures, but are most extensively developed within the Mdlelanga syncline of the Nkandla Inlier. Sedimentary and volcaniclastic lithologies of the Mkuzane Formation cap the Nsuze Group in the Mhlatuze and Nkandla inliers. Thickness of this formation is, however, highly variable having been subjected to pre-Vutshini Formation erosion. Through detailed reinterpretation of the stratigraphy of the Nkandla sub-basin we present a third order, (formation) scale, lithostratigraphic scheme encompassing all the formational units of the currently accepted stratigraphy within the main Pongola basin. This working model has the potential for lower-ranking units to be identified and be placed at their appropriate stratigraphic levels in future.
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Gutiérrez-Alonso, G., J. Fernández-Suárez, Alan S. Collins, I. Abad, and F. Nieto. "Amazonian Mesoproterozoic basement in the core of the Ibero-Armorican Arc: 40Ar/39Ar detrital mica ages complement the zircon's tale." Geology 33, no. 8 (August 1, 2005): 637–40. http://dx.doi.org/10.1130/g21485ar.1.
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Abstract The 40Ar/39Ar age data on single detrital muscovite grains complement U-Pb zircon ages in provenance studies, as micas are mostly derived from proximal sources and record low-temperature processes. Ediacaran and Cambrian sedimentary rocks from northwest Iberia contain unmetamorphosed detrital micas whose 40Ar/39Ar age spectra suggest an Amazonian–Middle American provenance. The Ediacaran sample contained only Neoproterozoic micas (590–783 Ma), whereas the Cambrian sample contained three age groups: Neoproterozoic (550–640 Ma, Avalonian–Cadomian–Pan African), Mesoproterozoic- Neoproterozoic boundary (ca. 920–1060 Ma, Grenvillian-Sunsas), and late Paleoproterozoic (ca. 1580–1780 Ma, Rio Negro). Comparison of 40Ar/39Ar muscovite ages with published detrital zircon age data from the same formations supports the hypothesis that the Neoproterozoic basins of northwest Iberia were located in a peri-Amazonian realm, where the sedimentary input was dominated by local periarc sources. Tectonic slivering and strike-slip transport along the northern Gondwanan margin affected both the basins and fragments of basement that were transferred from Amazonian to northern African realms during the latest Neoproterozoic–earliest Cambrian. Exhumation and erosion of these basement sources caused shedding of detritus to the Cambrian basins, in addition to detritus sourced in the continental mainland. The apparent dominance of Rio Negro–aged micas in the Cambrian sandstone suggests the presence of unexposed basement of that age beneath the core of the Ibero-Armorican Arc.
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Ghienne, Jean-François. "Late Ordovician sedimentary environments, glacial cycles, and post-glacial transgression in the Taoudeni Basin, West Africa." Palaeogeography, Palaeoclimatology, Palaeoecology 189, no. 3-4 (January 2003): 117–45. http://dx.doi.org/10.1016/s0031-0182(02)00635-1.
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Nadege Barbara Zagbayou, Nakpoh. "Nannostratigraphic Study of K/Pg Limit Formations of Cote d’Ivoire Offshore Sedimentary Basin of (West Africa)." Earth Sciences 6, no. 6 (2017): 164. http://dx.doi.org/10.11648/j.earth.20170606.19.
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Dossou, Prudence Mahutondji, Crépin Zevounou, Abdoukarim Alassane, Christophe Kaki, Moussa Boukari, and Daouda Mama. "Physico-Chemical Characteristics of Gushing Water Aquifers in the Coastal Sedimentary Basin of Benin (West Africa)." Journal of Geoscience and Environment Protection 09, no. 07 (2021): 149–63. http://dx.doi.org/10.4236/gep.2021.97010.
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