Journal articles: 'Basement Complex'

1

Bleeker, Wouter, John WF Ketchum, Valerie A. Jackson, and Michael E. Villeneuve. "The Central Slave Basement Complex, Part I: its structural topology and autochthonous cover." Canadian Journal of Earth Sciences 36, no. 7 (July 1, 1999): 1083–109. http://dx.doi.org/10.1139/e98-102.

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New field and geochronological data are used to define the distribution of Mesoarchean basement rocks in the south-central Slave Province. This distribution reflects a single contiguous basement terrane that we propose to call the Central Slave Basement Complex. It shows a structural topology that is internally consistent and compatible with known regional folding and faulting events. A sample of a proposed basement gneiss below the Courageous Lake greenstone belt, central Slave Province, has been dated by U-Pb methods and yields an age of 3325 ± 8 Ma, consistent with the new basement distribution. This sample also contains 2723 ± 3 Ma metamorphic zircon and ca. 2680 Ma titanite. The Central Slave Basement Complex is overlain by a thin, discontinuous, but distinctive cover sequence that includes minor volcanic rocks, clastic sedimentary rocks, and banded iron formation. All previously known and some new occurrences of this distinctive cover sequence occur in the immediate stratigraphic hanging wall of the Central Slave Basement Complex, locally overlying a preserved in situ unconformity. We propose to call this post-2.93 Ga cover sequence the Central Slave Cover Group. It is perhaps best typified by detrital chromite-bearing, fuchsitic quartzites. Formal formation names are proposed for the spatially separate occurrences of the Central Slave Cover Group. Detrital zircon ages are presented for one of the formations of the Central Slave Cover Group, the Patterson Lake Formation, which occurs on the western flank of a local basement culmination known as the Sleepy Dragon Complex. The detrital zircon data provide evidence for two discrete basement sources dated at ca. 2943 Ma and ca. 3147-3160 Ma. These detrital ages reinforce the depositional link between the Central Slave Cover Group and underlying crystalline rocks of the Central Slave Basement Complex.

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Clark, Lewis. "Groundwater abstraction from Basement Complex areas of Africa." Quarterly Journal of Engineering Geology and Hydrogeology 18, no. 1 (February 1985): 25–34. http://dx.doi.org/10.1144/gsl.qjeg.1985.018.01.05.

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Nhu, Ha Viet, Binh Van Duong, Tuan Anh Vo, and Kien Tran Pham. "Using numerical modeling method for design and constructive controlling of excavation wall in Madison Building, Ho Chi Minh city." Journal of Mining and Earth Sciences 61, no. 3 (June 30, 2020): 19–27. http://dx.doi.org/10.46326/jmes.2020.61(3).03.

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The basement of a high-rise building is the optimal space for technical systems and parking. However, the construction in narrow urban areas usually has many unstable hazards. In this study, a numerical model has been established and calibrated using the finite element method on Plaxis 2D software that allowed well control of the design and construction processes of the Madison Building basement. The model covers all structural elements and complex engineering geology conditions. Displacements of the excavation wall and surrounding ground base subsidence were analyzed corresponding to the constructive phases of three basements. The analysis results of the numerical model were consistent with the actual construction process that is useful for design and constructive controlling of the excavation wall.

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Van Baelen, Hervé, and Manuel Sintubin. "Kinematic consequences of an angular unconformity in simple shear: an example from the southern border of the Lower Palaeozoic Rocroi inlier (Naux, France)." Bulletin de la Société Géologique de France 179, no. 1 (January 1, 2008): 73–87. http://dx.doi.org/10.2113/gssgfbull.179.1.73.

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AbstractThe presence of an angular unconformity in combination with complex structures in the basement, lacking in the cover, is commonly seen as an indication for an orogenic event pre-dating the unconformity. The recognition of such an older orogenic event becomes, however, less evident in areas where both cover and basement were deformed together during an orogen post-dating the angular unconformity.The validity of this common interpretation has been evaluated at the southern border of the Lower Palaeozoic Rocroi basement inlier (Naux, northern France), where the basement-cover interface is very well exposed. This basement-cover interface, showing an angular unconformity, has classically been interpreted as evidence for an early Palaeozoic tectonometamorphic event, called the Ardennian orogeny, though only one penetrative cleavage, co-genetic with the structures present in both cover and basement, can be observed.A detailed geometrical study shows, however, that the presence of a tilted basement, involving the angular unconformity, provokes a rheological heterogeneity that causes a contrasting response of basement and cover with respect to the Variscan shortening. While Variscan progressive deformation gave rise to a rather regular cleavage refraction pattern in the subhorizontal multilayer cover sequence, a complex deformation, expressed by non-cylindrical folds, boudinage and shearing developed in the basement. The basement-cover interface itself played no rheological role, but has been passively sheared and folded as a consequence of the deformation of the basement. This study proves that the deformed basement-cover interface, allowing to link deformation in basement and cover, is a necessary tool to properly interpret complex deformation in the basement. With respect to the regional geodynamic evolution of the northern parts of the Central European Variscides, our kinematic model indeed demonstrates that this classical outcrop area bears no evidence for an early Palaeozoic orogenic event, and that the angular unconformity reflects the late Silurian – early Devonian onset of the Ardenne-Eifel basin development, rather than a middle Ordovician Ardennian orogeny.

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Owonubi, Ayodele. "Pedogenic Forms of Iron in Soils Developed from Four Parent Materials." JOURNAL OF TROPICAL SOILS 25, no. 1 (January 22, 2020): 47. http://dx.doi.org/10.5400/jts.2020.v25i1.47-52.

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Information on the distribution of various forms of iron in soils are valuable in the study of soil genesis. The objective of this study was to to evaluate the pedogenic forms of iron in soils developed over basement complex and basaltic parent materials of the study area. Geologic units considered in the basement complex area were granite gneiss, biotite granite and migmatite. Stratified random sampling formed the basis for field work. Soil sampling was carried out by digging at least two soil profile pits in each geologic unit. Organically bound, amourphous and total iron oxides were estimated using 0.1 M sodium pyrophosphate, acidified (pH 3) ammonium oxalate, and dithionite-citrate-bicarbonate method, respectively. The total Fe in the soil samples were determined after a mixed acid digestion. In general, total iron fractions were statistically similar among the soils of basement complex geologic units but significantly lower than those of soils derived from basaltic rocks. However, the distribution of iron oxide fractions was similar among the basement and basaltic geologic units. Furthermore, there were significant differences in the distribution of iron oxides in the B horizons of basement complex derived soils. Consequently, the quantity of iron oxides in the B horizon was in the order migmatite > biotite granite > granite gneiss. About 70% of total iron oxides in the soils over granite gneiss, biotite granite and basaltic rocks was amorphous in nature. Furthermore, total iron oxides constitute less than 20% of total clay both in the basement complex and basaltic soils.

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Cui, Zhao, Ming-Hui Zhao, Su-Xia Wang, Gang Liu, Wan-Zhong Zou, and Hai-Yan Wang. "Concurrent Antiglomerular Basement Membrane Disease and Immune Complex Glomerulonephritis." Renal Failure 28, no. 1 (January 2006): 7–14. http://dx.doi.org/10.1080/08860220500461195.

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Baer, Gidon, Michael Beyth, and Ze'ev Reches. "Dikes emplaced into fractured basement, Timna Igneous Complex, Israel." Journal of Geophysical Research: Solid Earth 99, B12 (December 10, 1994): 24039–50. http://dx.doi.org/10.1029/94jb02161.

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Raji, B. A., and S. A. Alagbe. "Hydrochemical facies in parts of the Nigerian basement complex." Environmental Geology 29, no. 1-2 (January 30, 1997): 46–49. http://dx.doi.org/10.1007/s002540050102.

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Doughty, P. T., R. A. Price, and R. R. Parrish. "Geology and U-Pb geochronology of Archean basement and Proterozoic cover in the Priest River complex, northwestern United States, and their implications for Cordilleran structure and Precambrian continent reconstructions." Canadian Journal of Earth Sciences 35, no. 1 (January 1, 1998): 39–54. http://dx.doi.org/10.1139/e97-083.

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Precambrian basement rocks exposed within tectonic windows in the North American Cordillera help to define the Precambrian crustal structure of western North America and possible reconstructions of the Late Proterozoic supercontinent Rodinia. New geologic mapping and U-Pb dating in the infrastructure of the Priest River metamorphic complex, northern Idaho, documents the first Archean basement (2651 ± 20 Ma) north of the Snake River Plain in the North American Cordillera. The Archean rocks are exposed in the core of an antiform and mantled by a metaquartzite that may represent the nonconformity between basement and the overlying Hauser Lake gneiss, which is correlated with the Prichard Formation of the Belt Supergroup. A structurally higher sheet of augen gneiss interleaved with the Hauser Lake gneiss yields a U-Pb zircon crystallization age somewhat greater than 1577 Ma. The slivers of augen gneiss were tectonically interleaved with the surrounding Hauser Lake gneiss near the base of the Spokane dome mylonite zone, which arches across this part of the Priest River complex. We conclude that the Spokane dome mylonite zone lies above the Archean basement-cover contact and that it was, in part, equivalent to the basal décollement of the Rocky Mountain fold and thrust belt. New U-Pb dates on metamorphic monazite and xenotime reveal peak metamorphism at ca. 72 Ma, compatible with movement along the Spokane dome mylonite zone at that time. The Archean basement could be interpreted as the western extension of the Hearne province, or a new Archean basement terrane separated from the Hearne province by an Early Proterozoic suture. The unique assemblage of 2.65 Ga basement, ~1.58 Ga felsic intrusive rocks, and the Middle Proterozoic Belt Supergroup can be used as a piercing point for the identification of the conjugate margin to Laurentia. Our new dating supports previous correlations of Australia's Gawler craton (2.55-2.65 Ga) and its 1590 Ma plutons with the Priest River complex basement gneisses. The Priest River complex basement may be a piece of eastern Australia stranded during rifting of the supercontinent Rodina in the Late Proterozoic.

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Tamayo, Rodolfo A., Graciano P. Yumul, René C. Maury, Hervé Bellon, Joseph Cotten, Mireille Polvé, Thierry Juteau, and Cliff Querubin. "Complex origin for the south-western Zamboanga metamorphic basement complex, Western Mindanao, Philippines." Island Arc 9, no. 4 (July 18, 2008): 638–52. http://dx.doi.org/10.1111/j.1440-1738.2000.00308.x.

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Tamayo, Rodolfo A., Graciano P. Yumul, Rene C. Maury, Herve Bellon, Joseph Cotten, Mireille Polve, Thierry Juteau, and Cliff Querubin. "Complex origin for the south-western Zamboanga metamorphic basement complex, Western Mindanao, Philippines." Island Arc 9, no. 4 (December 2000): 638–52. http://dx.doi.org/10.1046/j.1440-1738.2000.00308.x.

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McCaffrey, K. J. W., R. E. Holdsworth, J. Pless, B. S. G. Franklin, and K. Hardman. "Basement reservoir plumbing: fracture aperture, length and topology analysis of the Lewisian Complex, NW Scotland." Journal of the Geological Society 177, no. 6 (June 18, 2020): 1281–93. http://dx.doi.org/10.1144/jgs2019-143.

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Upfaulted ridges of Neoarchean crystalline basement rocks formed in the Faeroe-Shetland basin as a consequence of Mesozoic rift processes and are an active target for oil exploration. We carried out a comprehensive fault and fracture attribute study on the extensive exposures of geologically equivalent crystalline basement rocks onshore in NW Scotland (Lewisian Gneiss Complex) as an analogue for the offshore oil and gas reservoirs of the uplifted Rona Ridge basement high. Our analysis shows a power-law distribution for fracture sizes (aperture and length), with random to clustered spacing and high connectivity indices. Regional variations between the Scottish mainland and the Outer Hebrides are recognized that compare directly with variations observed along the Rona Ridge in the Faeroe-Shetland basin. Here we develop a model for the scaling properties of the fracture systems in which variations in the aperture attributes are a function of the depth of erosion beneath the top basement unconformity. More generally, the combination of size, spatial and connectivity attributes we found in these basement highs demonstrates that they can form highly effective, well-plumbed reservoir systems in their own right.Supplementary material: Additional methods and results are available at: https://doi.org/10.6084/m9.figshare.c.5017139Thematic collection: This article is part of the The Geology of Fractured Reservoirs collection available at: https://www.lyellcollection.org/cc/the-geology-of-fractured-reservoirs

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Cordey, Fabrice, and Jean-Jacques Cornée. "New radiolarian assemblages from La Désirade Island basement complex (Guadeloupe, Lesser Antilles arc) and Caribbean tectonic implications." Bulletin de la Société Géologique de France 180, no. 5 (September 1, 2009): 399–409. http://dx.doi.org/10.2113/gssgfbull.180.5.399.

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Abstract New radiolarian assemblages of Late Jurassic age were extracted from seven chert localities of the basement complex of La Désirade Island (Guadeloupe), the oldest geological unit of the Lesser Antilles arc and the eastern Caribbean region. These fauna range in age from Kimmeridgian or early Tithonian to early or early late Tithonian, showing that La Désirade cherts are not all coeval, contrary to what was established by previous studies. Furthermore, the close spatial association of cherts and volcanic elements composed of basaltic flows and volcaniclastics suggests a mixed setting of hydrothermal siliceous deposits and biogenous sedimentation consistent with an arc-related oceanic setting rather than an ophiolite-type oceanic crust. As the youngest age is obtained to the northwest of the basement complex whereas older data are found to the southeast, it also suggests that La Désirade basement complex may have undergone some structural stacking consistent with an accretion-type geodynamic setting. Our biochronological data provide a preliminary tectonic model of an eastward subduction zone for Lesser Antilles arc basement emplacement during the Mesozoic.

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Owen, J. V., R. Corney, J. Dostal, and A. Vaughan. "Significance of “gneissic” rocks in the Liscomb Complex, Nova Scotia." Canadian Journal of Earth Sciences 47, no. 6 (June 2010): 927–40. http://dx.doi.org/10.1139/e10-019.

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The Liscomb Complex comprises Late Devonian intrusive rocks (principally peraluminous granite) and medium- to high-grade metamorphic rocks (“gneisses”) that collectively are hosted by low-grade (greenschist facies) metasediments of the Cambro-Ordovician Meguma Group. The conventional view that these “gneisses” contain high-grade mineral assemblages and represent basement rocks has recently been challenged, and indeed, some of the rocks previously mapped as gneisses, particularly metapelites, have isotopic compositions resembling the Meguma Group. Amphibole-bearing enclaves in the Liscomb plutons, however, are isotopically distinct and in this regard resemble xenoliths of basement gneisses in the Popes Harbour lamprophyre dyke, south of the Liscomb area. Metasedimentary enclaves with Meguma isotopic signatures can contain garnets with unzoned cores (implying high temperatures) that host high-grade minerals (prismatic sillimanite, spinel, and (or) corundum) and are enclosed by retrograde-zoned rims. These features are interpreted here as having formed during and following the attainment of peak temperatures related to Liscomb magmatism. The amphibole-bearing meta-igneous rocks described here contain cummingtonite or hornblendic amphibole and occur as enclaves in granodioritic to tonalitic plutons. They are mineralogically, texturally, and isotopically distinct from Meguma metasediments and at least some of the plutonic rocks that enclose them, so remain the most likely candidate for basement rocks in the Liscomb Complex.

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Ajayi, Owolabi, and C. W. Adegoke-Anthony. "Groundwater prospects in the basement complex rocks of southwestern Nigeria." Journal of African Earth Sciences (and the Middle East) 7, no. 1 (January 1988): 227–35. http://dx.doi.org/10.1016/0899-5362(88)90070-x.

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Olasehinde, P. I., P. C. Pal, and A. E. Annor. "Aeromagnetic anomalies and structural lineaments in the Nigerian Basement Complex." Journal of African Earth Sciences (and the Middle East) 11, no. 3-4 (January 1990): 351–55. http://dx.doi.org/10.1016/0899-5362(90)90014-6.

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Barr, Sandra M., Robert P. Raeside, and Otto van Breemen. "Grenvillian basement in the northern Cape Breton Highlands, Nova Scotia." Canadian Journal of Earth Sciences 24, no. 5 (May 1, 1987): 992–97. http://dx.doi.org/10.1139/e87-096.

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The northernmost Cape Breton Highlands are underlain by the Blair River Complex, a distinctive assemblage of basement rocks including felsic and mafic gneisses, foliated gabbroic to granitic rocks, anorthosite, and foliated and unfoliated varieties of syenite. Major faults and mylonite zones separate the complex from schists, gneisses, and granitoid rocks typical of the rest of the Cape Breton Highlands. U–Pb dating of zircon from the Lowland Brook syenite of the Blair River Complex indicates a metamorphic age of [Formula: see text] and an igneous age of 1100–1500 Ma. These ages and the distinctive rock assemblage allow the Blair River Complex to be correlated with the Grenvillian rocks in the Long Range Inlier and Indian Head Range Complex of western Newfoundland. This is the first confirmed report of Grenvillian basement in Cape Breton Island, and it places new constraints on correlations between Newfoundland and the northern mainland Appalachians.

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Putiš, Marián, Peter Ivan, Milan Kohút, Ján Spišiak, Pavol Siman, Martin Radvanec, Pavel Uher, et al. "Meta-igneous rocks of the West-Carpathian basement, Slovakia: indicators of Early Paleozoic extension and shortening events." Bulletin de la Société Géologique de France 180, no. 6 (October 1, 2009): 461–71. http://dx.doi.org/10.2113/gssgfbull.180.6.461.

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Abstract The paper reviews the main West-Carpathian Early Paleozoic metamorphosed originally sedimentary-magmatic complexes, dated by SHRIMP on zircons, as indicators of crustal extension and shortening events. Igneous precursors of a Layered Amphibolite Complex (LAC) – fractionated upper mantle gabbros to diorites, dated at 503 ± 4 and 492 ± 4 Ma from the North-Veporic, or 480 ± 5 and 450 ± 6 Ma from the Tatric basement are contemporaneous with subaluminous to metaluminous I-type (507 ± 4 Ma, the South-Veporic basement), peraluminous S-type (497 ± 4 Ma, the South-Veporic basement; 516 ± 7, 485 ± 6 and 462 ± 6 Ma, the North-Veporic basement; 497 ± 6, 472 ± 6 and 450 ± 6 Ma, the Tatric basement), alkaline A-type (511 ± 6 Ma, South-Veporic basement) granitic orthogneisses and calcalkaline rhyolitic (482 ± 6 Ma) and dacitic (476 ± 7 Ma) metavolcanics (Gemeric basement), indicating a magmatic immature back arc setting. The ages point to Middle/Late Cambrian, Early and Late Ordovician magmatic phases, coeval with the extension in the northern Gondwana margin. Separation of an inferred Avalonian and/or Galatian terranes distal continental ribbon corresponds with the opening of a Medio-European Basin. A 430-390 Ma dated MP/HP metamorphic event, recorded in the LAC and associated orthogneisses, occurred in the area of thinned immature back arc basin crust due to closure of the Medio-European Basin. Thus a distal Gondwana continental ribbon north of this basin could be an eastward lateral pendant of Armorica, derived from Galatian terrane. Metaophiolites of the Pernek Group (a metagabbrodolerite dated at 371 ± 4 Ma) in the Tatric basement, analogous to island-arc tholeiites and back-arc basin basalts, indicate a back-arc basin setting north of a 430-390 Ma old northward dipping subduction/collision zone, dividing the northward drifting western Galatian terrane microplate from the Gondwana margin. Some metabasites of the Gemeric basement might indicate Late Devonian to Mississippian opening of a peri-Gondwanan Paleotethyan oceanic basin: a 383 ± 3 Ma old remelted metagabbro (482 ± 9 Ma) from the Klátov gneiss-amphibolite complex, ca. 385 Ma old porphyritic metabasite of the Zlatník ophiolite complex, as well as a 350 ± 5 Ma old HP metabasite as tectonic fragment within the Rakovec Group. The closure of Devonian-Mississippian basins, accompanied by medium-pressure (the Pernek Group) to high-pressure (blueschist to eclogitic tectonic fragments in greenschist facies rocks of the Rakovec Group) metamorphism, occurred in late Carboniferous to early Permian, when Paleotethyan realm complexes accreted to a Galatian terrane microplate, the latter represented by the older and the higher-grade Tatric and Veporic basement complexes.

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Ng, C. W. W., Jiangwei Shi, David Mašín, Huasheng Sun, and G. H. Lei. "Influence of sand density and retaining wall stiffness on three-dimensional responses of tunnel to basement excavation." Canadian Geotechnical Journal 52, no. 11 (November 2015): 1811–29. http://dx.doi.org/10.1139/cgj-2014-0150.

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Basement excavation inevitably causes stress changes in the ground, leading to soil movements that may affect the serviceability and safety of adjacent tunnels. Despite paying much attention to the basement–tunnel interaction, previous research has mainly focused on the influence of tunnel location in relation to the basement, tunnel stiffness, and excavation geometry. The effects of sand density and basement wall stiffness on nearby tunnels due to excavation, however, have so far been neglected. A series of three-dimensional centrifuge tests were thus carried out in this study to investigate these effects on the complex basement–tunnel interaction. Moreover, three-dimensional numerical analyses and a parametric study by adopting a hypoplastic sand model were conducted to improve the fundamental understanding of this complex problem, and calculation charts were developed as a design tool. When the basement was constructed directly above the existing tunnel, excavation-induced heave and strain were more sensitive to a change in soil density in the transverse direction than that in the longitudinal direction of the tunnel. Because a looser sand possesses smaller soil stiffness around the tunnel, the maximum tunnel elongation and transverse tensile strain increased by more than 20% as the relative sand density decreased by 25%. Moreover, the tensile strain induced along the longitudinal direction was insensitive to the stiffness of the retaining wall, but the tensile strain induced along the transverse direction was significantly reduced by a stiff wall. When the basement was constructed at the side of the existing tunnel, the use of a diaphragm wall reduced the maximum settlements and tensile strains induced in the tunnel by up to 22% and 58%, respectively, compared with the use of a sheet pile wall. Under the same soil density and wall stiffness, excavation-induced maximum movement and tensile strains in the tunnel located at a side of the basement were about 30% of the measured values in the tunnel located directly beneath the basement centre.

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Degtyarev, K. E., A. A. Tretyakov, E. B. Salnikova, and A. B. Kotov. "Kumystin granosyenites complex of the late Cryogenian in Bolshoi Karatau (South Kazakhstan), age substantiation." Доклады Академии наук 484, no. 5 (May 16, 2019): 579–83. http://dx.doi.org/10.31857/s0869-56524845579-583.

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The results of U–Pb geochronological studies of quartz syenites of the Kumystin complex of the Bolshoi Karatau ridge in southern Kazakhstan are presented and their late Neoproterozoic (717 ± 4 Ma) age is substantiated. Kumystin syenites complex together with rhyolites and basalts of the Kainar Formation are the youngest formations taking part in the basement of Karatau-Dzhebagly precambrian massif and formed in the second half of Cryogenian. The data set about the ages of the youngest complexes taking part in the basement of precambrian massifs of the Western part of the Central Asian belt indicates that the ending of magmatic activity within various massifs occurred asynchronously during the Neoproterozoic.

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Bleeker, Wouter, John WF Ketchum, and W. J. Davis. "The Central Slave Basement Complex, Part II: age and tectonic significance of high-strain zones along the basement-cover contact." Canadian Journal of Earth Sciences 36, no. 7 (July 1, 1999): 1111–30. http://dx.doi.org/10.1139/e99-007.

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The basement-cover high-strain zone enveloping parts of the Sleepy Dragon Complex, northeast of Yellowknife, Slave Province, Canada, has been reinvestigated. Integrated stratigraphic, structural, and geochronological data show that the high-strain zone is of regional extent and is best interpreted as a décollement between crystalline, ca. 2.9-3.3 Ga rocks of the Central Slave Basement Complex and pre-2687 Ma cover rocks. Three temporally distinct mafic dyke swarms occur within the high-strain zone. The two oldest of these constrain the timing of the high-strain event to between 2734 ± 2 and 2687 ± 1 Ma. At the time of décollement development, the cover stratigraphy consisted of (i) the Central Slave Cover Group, a thin, pre-2734 Ma succession of mafic and ultramafic volcanic rocks, conglomerates, fuchsitic quartzites, minor rhyolites, and banded iron formation; and (ii) an overlying sequence of tholeiitic pillow basalts. The Central Slave Cover Group is considered to be autochthonous, whereas a variety of evidence suggests that the pillow basalts are parautochthonous to possibly allochthonous. The transport direction in the décollement was from northeast to southwest, and maximum displacement was probably on the order of 10 to several tens of kilometres. Presently, the décollement appears discontinuous due to younger intrusive and erosional events. Around most of the southern flanks of the Sleepy Dragon Complex, the crystalline core of the complex consists of post-décollement intrusive rocks and (or) is unconformably overlain by parts of the Yellowknife Supergroup that are younger than 2687 Ma. Lineation patterns in these younger rocks reflect regional deformation events that postdate and are unrelated to the décollement. The new data allow two tectonic models for development of the décollement: (i) a contractional thrusting model, involving collision of an eastern Slave Province arc terrane; or (ii) a syn-greenstone belt extensional model.

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Sami, S., T. Fischer-Scherl, R. W. Hoffmann, and C. Pfeil-Putzien. "Immune Complex-mediated Glomerulonephritis Associated with Bacterial Kidney Disease in the Rainbow Trout (Oncorhynchus mykiss)." Veterinary Pathology 29, no. 2 (March 1992): 169–74. http://dx.doi.org/10.1177/030098589202900210.

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Rainbow trout ( Oncorhynchus mykiss) developed a post-infectious chronic membranous glomerulonephritis 15 months after they had been experimentally infected with Renibacterium salmoninarum. Histologically, peritubular and periglomerular fibrosis, hypercellular glomeruli with occluded Bowman's space, and partial or complete adhesion to Bowman's capsule were constant features. Electron microscopy revealed thickened glomerular basement membranes with spikes accompanied by finely granular electron-dense deposits at the epithelial side and dense material in the mesangial matrix. Indirect immunofluorescence indicated linear immunoglobulin deposits along the glomerular basement membrane. The presence of R. salmoninarum was demonstrated by culture and by indirect immunofluorescence. Low serum hemagglutination-inhibiting antibody titers were demonstrated.

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Kullerud, Kåre, Dmitry Zozulya, Muriel Erambert, and Erling J. K. Ravna. "Solid solution between potassic alkali amphiboles from the silica-rich Kvaløya lamproite, West Troms Basement Complex, northern Norway." European Journal of Mineralogy 25, no. 6 (March 11, 2014): 935–45. http://dx.doi.org/10.1127/0935-1221/2013/0025-2340.

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Adeoye-Oladapo, O., K. Mogaji, and M. Oladapo. "Multi-Array Hydro-Geoelectric Characterization of a Crystalline Basement Complex Environment." Physical Science International Journal 8, no. 2 (January 10, 2015): 1–18. http://dx.doi.org/10.9734/psij/2015/17444.

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Olayinka, A. Idowu. "Electromagnetic Profiling for Groundwater in Precambrian Basement Complex Areas of Nigeria." Hydrology Research 21, no. 3 (June 1, 1990): 205–16. http://dx.doi.org/10.2166/nh.1990.0016.

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Ground electromagnetic profiling, using a Geonics EM34-3 instrument, has been employed to identify areas of high conductivity in a Precambrian basement complex terrain of Nigeria. Field examples, conducted as part of a rural water supply programme, are presented. They indicate that the apparent conductivities are generally lower than about 60 mmho m−1. Subsequent borehole drilling suggests a good correlation between high EM34 anomalies, deep weathering and high well yield (> 1 1 s−1). On the other hand, boreholes sited on conductivity lows penetrated a thinner regolith with relatively lower yields.

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Lawal, M., S. A. Ayomaya, J. O. Ojero, A. Muhammad, N. A. Yelwa, J. Bello, and A. Bello. "Integrated Geology and Geochemical analysis of Eruku Basement Complex, Southwestern Nigeria." Nigerian Journal of Basic and Applied Sciences 25, no. 1 (July 12, 2018): 63. http://dx.doi.org/10.4314/njbas.v25i1.9.

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Ayuba, R., F. Akpah, V. Omonona, and A. Auduson. "Geoelectrical Investigation of Basement Complex Areas of Lokoja, North-Central Nigeria." British Journal of Applied Science & Technology 7, no. 6 (January 10, 2015): 573–84. http://dx.doi.org/10.9734/bjast/2015/15526.

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Georgiopoulou, Aggeliki, Patrick M. Shannon, Fabio Sacchetti, Peter D. W. Haughton, and Sara Benetti. "Basement-controlled multiple slope collapses, Rockall Bank Slide Complex, NE Atlantic." Marine Geology 336 (February 2013): 198–214. http://dx.doi.org/10.1016/j.margeo.2012.12.003.

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Jones, M. J. "The weathered zone aquifers of the basement complex areas of Africa." Quarterly Journal of Engineering Geology and Hydrogeology 18, no. 1 (February 1985): 35–46. http://dx.doi.org/10.1144/gsl.qjeg.1985.018.01.06.

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Richardson, Rebecca J., Jan M. Gebauer, Jin-Li Zhang, Birgit Kobbe, Douglas R. Keene, Kristina Røkenes Karlsen, Stefânia Richetti, et al. "AMACO Is a Component of the Basement Membrane–Associated Fraser Complex." Journal of Investigative Dermatology 134, no. 5 (May 2014): 1313–22. http://dx.doi.org/10.1038/jid.2013.492.

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Odukoya, A. M. "Geochemical and quality assessment of groundwater in some Nigerian basement complex." International Journal of Environmental Science and Technology 12, no. 11 (May 1, 2015): 3643–56. http://dx.doi.org/10.1007/s13762-015-0789-y.

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Jie, Tang, Ian Lerche, and Jeff Cogan. "Elastic flexure with compressive thrusting of the Green River Basin, Wyoming, U.S.A." Geological Magazine 127, no. 4 (July 1990): 349–59. http://dx.doi.org/10.1017/s0016756800014904.

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AbstractAn inverse elastic flexural model with compressive thrusting is applied to the northern Green River Basin, Wyoming. A combination of six parameters in the model determines the deformational processes of basement due to sediment load and compressive thrusting: flexural rigidity, lateral stress, bending moment, initial load, dip angle of the basement, and length. The results suggest that the northern Green River Basin develops dominantly as an elastic flexural response to the deformation of basement due to compressive thrusting of the Wind River Mountains. From the unloaded basement configuration we estimate that by latest Cretaceous time the thrust fault activity of the Wind River Mountains led the basement to uplift about 7 km above the hinge point at the margin of the basin and to form a complex faulted mountain system. The maximum uplift rate is about 100 m/Ma at the Wind River Mountains. Also we predict the sedimentary pattern, and provenance of sediments of Tertiary units, from the unloaded basement geometry. Thus the inverse elastic flexural model can be used to assess the evolutionary processes involved in a basin under compressive thrusting.

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Xu, Lingling, Abhijit Nirwane, and Yao Yao. "Basement membrane and blood–brain barrier." Stroke and Vascular Neurology 4, no. 2 (December 5, 2018): 78–82. http://dx.doi.org/10.1136/svn-2018-000198.

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The blood–brain barrier (BBB) is a highly complex and dynamic structure, mainly composed of brain microvascular endothelial cells, pericytes, astrocytes and the basement membrane (BM). The vast majority of BBB research focuses on its cellular constituents. Its non-cellular component, the BM, on the other hand, is largely understudied due to its intrinsic complexity and the lack of research tools. In this review, we focus on the role of the BM in BBB integrity. We first briefly introduce the biochemical composition and structure of the BM. Next, the biological functions of major components of the BM in BBB formation and maintenance are discussed. Our goal is to provide a concise overview on how the BM contributes to BBB integrity.

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Bradford, John H., Lee M. Liberty, Mitch W. Lyle, William P. Clement, and Scott Hess. "Imaging complex structure in shallow seismic-reflection data using prestack depth migration." GEOPHYSICS 71, no. 6 (November 2006): B175—B181. http://dx.doi.org/10.1190/1.2335659.

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Prestack depth migration (PSDM) analysis has the potential to significantly improve the accuracy of both shallow seismic reflection images and the measured velocity distributions. In a study designed to image faults in the Alvord Basin, Oregon, at depths from [Formula: see text], PSDM produced a detailed reflection image over the full target depth range. In contrast, poststack time migration produced significant migration artifacts in the upper [Formula: see text] that obscured reflection events and limited the structural interpretation in the shallow section. Additionally, an abrupt increase from [Formula: see text] to [Formula: see text] in the PSDM velocity model constrained the interpretation of the transition from sedimentary basin fill to basement volcanic rocks. PSDM analysis revealed a complex extensional history with at least two distinct phases of basin growth and a midbasin basement high that forms the division between two major basin compartments.

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Kurpakus, M. A., E. L. Stock, and J. C. Jones. "Analysis of wound healing in an in vitro model: early appearance of laminin and a 125 × 10(3) Mr polypeptide during adhesion complex formation." Journal of Cell Science 96, no. 4 (August 1, 1990): 651–60. http://dx.doi.org/10.1242/jcs.96.4.651.

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The adhesion complex, which plays an important role in cell-substratum attachment, consists of a cellular hemidesmosomal plaque, anchoring filaments, the basement membrane zone and anchoring fibrils. An analysis of the temporal sequence of assembly of the adhesion complex was undertaken in an in vitro model of epithelial cell wound healing by immunofluorescence and electron microscopy. A monoclonal antibody directed against a 125K (K = 10(3) Mr) polypeptide (mAbHD), bullous pemphigoid (BP) autoantibodies, antibodies directed against collagen type VII and laminin antibodies were used as markers for anchoring filaments, the hemidesmosome, anchoring fibrils and the laminin component of the basement membrane zone, respectively. Fluorescence labeling could be detected with mAbHD before labeling with BP autoantibodies or collagen type VII antibodies. Laminin fluorescence was detected at the same time as mAbHD. Furthermore, the 125K polypeptide and laminin were located extracellularly prior to the appearance of BP antigen and collagen type VII. The appearance of the hemidesmosomal plaque at the electron microscope level succeeded the localization of BP antigen in basal cells detected by immunofluorescence microscopy. No evidence for the coordinated appearance of BP antigen, collagen type VII and laminin was observed in this model. We discuss the possibility that the 125K protein and laminin may play roles in the initiation of complex formation. Furthermore, although basement membrane zone components were detected early in adhesion complex re-formation, formation of the lamina densa region of the basement membrane zone followed the appearance of the hemidesmosomal plaque, indicating a role for the hemidesmosomal plaque in organizing the structure of the lamina densa.

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Martins, Cristiano M., Valeria C. Barbosa, and João B. Silva. "Simultaneous 3D depth-to-basement and density-contrast estimates using gravity data and depth control at few points." GEOPHYSICS 75, no. 3 (May 2010): I21—I28. http://dx.doi.org/10.1190/1.3380225.

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We have developed a gravity-inversion method for simultaneously estimating the 3D basement relief of a sedimentary basin and the parameters defining a presumed parabolic decay of the density contrast with depth in a sedimentary pack, assuming prior knowledge about the basement depth at a few points. The sedimentary pack is approximated by a grid of 3D vertical prisms juxtaposed in both horizontal directions of a right-handed coordinate system. The prisms’ thicknesses represent the depths to the basement and are the parameters to be estimated from the gravity data. To estimate the parameters defining the parabolic decay of the density contrast with depth and to produce stable depth-to-basement estimates, we imposed smoothness on the basement depths and proximity between estimated and known depths at boreholes. We applied our method to synthetic data from a simulated complex 3D basement relief with two sedimentary sections having distinct parabolic laws describing the density-contrast variation with depth. The results provide good estimates of the true parameters of the parabolic law of density-contrast decay with depth and of the basement relief. Inverting the gravity data from the onshore and part of the shallow offshore Almada Basin on Brazil’s northeastern coast shows good correlation with known structural features.

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Silva Dias, Fernando J., Valeria C. Barbosa, and João B. Silva. "2D gravity inversion of a complex interface in the presence of interfering sources." GEOPHYSICS 72, no. 2 (March 2007): I13—I22. http://dx.doi.org/10.1190/1.2424545.

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We present a new semiautomatic gravity interpretation method for estimating a complex interface between two media containing density heterogeneities (referred to as interfering sources) that give rise to a complex and interfering gravity field. The method combines a robust fitting procedure and the constraint that the interface is very smooth near the interfering sources, whose approximate horizontal coordinates are defined by the user. The proposed method differs from the regional-residual separation techniques by using no spectral content assumption about the anomaly produced by the interface to be estimated, i.e., the interface can produce a gravity response containing both low- and high-wavenumber features. As a result, it may be applied to map the relief of a complex interface in a geologic setting containing either shallow or deep-seated interfering sources. Tests conducted with synthetic data show that the method can be of utility in estimating the basement relief of a sedimentary basin in the presence of salt layers and domes or in the presence of mafic intrusions in the basement or in both basement and the sedimentary section. The method was applied to real gravity data from two geologic settings having different kinds of interfering sources and interfaces to be interpreted: (1) the interface between the upper and lower crusts over the Bavali shear zone of southern India and (2) the anorthosite-tonalite interface over the East Bull Lake gabbro-anorthosite complex outcrop in Ontario, Canada.

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Lipp, Sarah N., Kathryn R. Jacobson, David S. Hains, Andrew L. Schwarderer, and Sarah Calve. "3D Mapping Reveals a Complex and Transient Interstitial Matrix During Murine Kidney Development." Journal of the American Society of Nephrology 32, no. 7 (April 19, 2021): 1649–65. http://dx.doi.org/10.1681/asn.2020081204.

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BackgroundThe extracellular matrix (ECM) is a network of proteins and glycosaminoglycans that provides structural and biochemical cues to cells. In the kidney, the ECM is critical for nephrogenesis; however, the dynamics of ECM composition and how it relates to 3D structure during development is unknown.MethodsUsing embryonic day 14.5 (E14.5), E18.5, postnatal day 3 (P3), and adult kidneys, we fractionated proteins based on differential solubilities, performed liquid chromatography–tandem mass spectrometry, and identified changes in ECM protein content (matrisome). Decellularized kidneys were stained for ECM proteins and imaged in 3D using confocal microscopy.ResultsWe observed an increase in interstitial ECM that connects the stromal mesenchyme to the basement membrane (TNXB, COL6A1, COL6A2, COL6A3) between the embryo and adult, and a transient elevation of interstitial matrix proteins (COL5A2, COL12A1, COL26A1, ELN, EMID1, FBN1, LTBP4, THSD4) at perinatal time points. Basement membrane proteins critical for metanephric induction (FRAS1, FREM2) were highest in abundance in the embryo, whereas proteins necessary for integrity of the glomerular basement membrane (COL4A3, COL4A4, COL4A5, LAMB2) were more abundant in the adult. 3D visualization revealed a complex interstitial matrix that dramatically changed over development, including the perinatal formation of fibrillar structures that appear to support the medullary rays.ConclusionBy correlating 3D ECM spatiotemporal organization with global protein abundance, we revealed novel changes in the interstitial matrix during kidney development. This new information regarding the ECM in developing kidneys offers the potential to inform the design of regenerative scaffolds that can guide nephrogenesis in vitro.

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Aisabokhae, Joseph, and Moses Adeoye. "Spatial distribution of radiogenic heat in the Iullemmeden basin – Precambrian basement transition zone, NW Nigeria." Geology, Geophysics and Environment 46, no. 3 (January 19, 2021): 238. http://dx.doi.org/10.7494/geol.2020.46.3.238.

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The area which transcends the Precambrian basement complex onto the Sokoto sector of the Iullemme-den basin in northwestern Nigeria presents a unique prospect for geothermal exploration research in the absence of regional heat production data, despite its tectonic history and depositional characteristics. In this study, geophysical exploration employing radiometric technique was adopted to classify the petrologic units within the fringes of the Iullemmeden basin and the adjoining crystalline basement complex so as to estimate the radiogenic heat potential within the terrain that may support geothermal considerations. Airborne radiometric measurements acquired over the area were digitized and processed to obtain radioelement concentration maps and the K/Th/U ternary map. Results show that the ranges of measured concentrations of 40K, 238U and 232Th are 4.6 to 18.9%, 0.7 to 4.9 ppm and 4.6 to 18.9 ppm respectively. Radiogenic heat estimation derived from radioelement data within eight petrologic units comprising quaternary sediments, schist, carbonates, shale/clay, younger granites, older granites, gneissic rock and migmatite showed that the lowest radiogenic heat production estimates ranging from 0.27–0.66 μW∙m−3 were recorded in the sedimentary terrain within the quaternary sediments while the highest radiogenic heat production values of between 2.04 to 2.34 μW∙m−3 were recorded in the basement com-plex within gneissic rocks. The spatial distribution of radiogenic heat in the area showed an increased heat gradient within the basement complex and a diminishing heat gradient over the Iullemmeded basin.

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Liwnicz, Boleslaw H., James L. Leach, Hwa-Shain Yeh, and Michael Privitera. "Pericyte Degeneration and Thickening of Basement Membranes of Cerebral Microvessels in Complex Partial Seizures: Electron Microscopic Study of Surgically Removed Tissue." Neurosurgery 26, no. 3 (March 1, 1990): 409–20. http://dx.doi.org/10.1227/00006123-199003000-00006.

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Abstract Complex partial seizures are associated with alterations in regional cerebral blood flow in abnormally spiking foci, as shown by positron emission tomography and single photon emission computed tomography, with an increase in flow ictally and a decrease interictally. Alterations of vasoregulation during ictal periods have also been described in animal seizure models. An electron microscopic study on human brain tissue from seven patients undergoing resections for the treatment of intractable complex partial seizures was performed to examine ultrastructural changes of the microvasculature and their locations within the microvessel wall. Biopsies were obtained intraoperatively from temporal lobe regions with electrocorticographically detected abnormal spiking and from regions without abnormality on electrocorticograms (control samples) removed as part of the therapeutic resection. A total of 539 microvessels from three regions were evaluated: spiking mesial temporal lobe, spiking lateral temporal cortex, and nonspiking (control) cortex. Evidence of pericyte degeneration (aggregates of cellular debris within the basement membrane) was noted in the majority of spiking area microvessels (76.7% in spiking mesial temporal cortex; 69.8% in spiking lateral temporal cortex) as compared with 37.8% of control microvessels (P< 0.0005). Morphometric studies revealed a significant increase in total wall thickness, pericyte-basement membrane unit thickness, pericyte cytoplasmic density, basement membrane density, and basement membrane thickness in microvessels from spiking (mesial and lateral temporal cortex), as compared to control areas (P< 0.01). No statistically significant difference was noted in pericyte coverage or pericyte or endothelial mitochondrial densities between microvessels in spiking and control regions. This study shows degeneration of pericytes, cells thought to play an essential role in microvascular hemodynamics, and thickening of microvessel walls in abnormally spiking brain regions in patients with intractable complex partial seizures. The pericyte degeneration and basement membrane thickening in abnormally spiking areas may explain alterations in vasoregulation, by a decrease in the microvascular compliance and in cross-capillary diffusion.

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Brown, E. H., G. E. Gehrels, and V. A. Valencia. "Chilliwack composite terrane in northwest Washington: Neoproterozoic–Silurian passive margin basement, Ordovician–Silurian arc inception." Canadian Journal of Earth Sciences 47, no. 10 (October 2010): 1347–66. http://dx.doi.org/10.1139/e10-047.

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The Chilliwack composite terrane in northwest Washington is part of an assemblage of mid-Paleozoic arc terranes extending from California to Alaska. Some terranes bear evidence of exotic origin, whereas others apparently formed proximal to western Laurentia, posing a complex problem in unraveling the Paleozoic accretionary history of the Cordillera. In our proposed broader definition, the Chilliwack composite terrane includes the volcanic and sedimentary East Sound and Chilliwack groups, and the plutonic and metamorphic Turtleback and Yellow Aster complexes. New zircon ages indicate that the plutonic and volcanic rocks are mutually related as parts of the same arc complex and that its inception was as old as Late Ordovician to Silurian, older than most other parts of the mid-Paleozoic terrane assemblage. Basement to the arc complex is a passive margin assemblage of metamorphosed quartzose sandstone and calc-silicate rock of the Yellow Aster Complex, bracketed in age by ca. 1000 Ma detrital zircons and 418 Ma intrusive rocks. This association of paragneiss basement and overlying and (or) intruding arc resembles that of older parts of the extensive Yukon–Tanana terrane in the northern Cordillera. Detrital zircon ages support a western Laurentian pericratonic origin for the paragneiss basement and the overlying arc. However, an early to mid-Paleozoic connection of this assemblage to the exotic outboard Alexander terrane is also indicated, based on (1) Mesoproterozoic and early Paleozoic detrital zircons in Devonian sedimentary rocks of the arc, and also in certain other pericratonic Devonian terranes and strata of the miogeocline; (2) Late Ordovician – Silurian igneous ages; and (3) an earliest Devonian or older metamorphic age of the basement paragneiss.

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Strachan, R. A., T. E. Johnson, C. L. Kirkland, P. D. Kinny, and T. Kusky. "A Baltic heritage in Scotland: Basement terrane transfer during the Grenvillian orogeny." Geology 48, no. 11 (July 21, 2020): 1094–98. http://dx.doi.org/10.1130/g47615.1.

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Abstract Archean basement inliers within the Northern Highland terrane (NHT), Scottish Caledonides, have been correlated with the Lewisian Gneiss Complex of the Laurentian foreland. New zircon U-Pb ages indicate that the NHT basement contains evidence for magmatism at 2823–2687 Ma and 1772–1655 Ma. The first group compares with crystallization ages of the foreland Archean gneisses. However, the second group, and a supracrustal unit, formed ∼100–250 m.y. after the youngest major phase of juvenile magmatism and sedimentation in the foreland. Also, there is no indication within the NHT basement of the Paleoproterozoic mafic and felsic intrusions common within the foreland, leading us to conclude that there is no firm basis for correlation of the two crustal blocks. The Caledonian Moine thrust, which separates the foreland and the NHT basement, is thought to have reworked a Grenvillian suture indicated by the presence of the ca. 1100–1000 Ma Eastern Glenelg eclogites. On the basis of the new isotopic data, we propose that the NHT basement was a fragment of Baltica that was emplaced onto Laurentia during the Grenvillian orogeny, representing a further example of basement terrane transfer in the circum–North Atlantic orogens.

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Goswami, Tapos Kumar. "Deformation of The Basement Gneissic Complex of The Assam Meghalaya Craton in and Around Sumer -Nayabunglow Area, Meghalaya, India." International Journal of Scientific Research 3, no. 3 (June 1, 2012): 149–51. http://dx.doi.org/10.15373/22778179/march2014/48.

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Migon, Piotr, and Magnus Johansson. "Lithological and structural influence on the development of basin-and-hill landscape within a basement complex in SW Sweden." Zeitschrift für Geomorphologie 48, no. 3 (September 29, 2004): 305–22. http://dx.doi.org/10.1127/zfg/48/2004/305.

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T, Aga, and Haruna A. I. "The field geology and petrography of the kofayi younger granite complex, central Nigeria." International Journal of Advanced Geosciences 7, no. 2 (July 22, 2019): 95. http://dx.doi.org/10.14419/ijag.v7i2.29055.

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The Kofayi Younger Granite Complex is one of the several anorogenic alkaline Younger Granite Complexes that is located approximately 45 kilometres north east of Jos, Nigeria. The complex is found to comprise of felsic rocks like; biotite-granites, biotite microgranites and granodiorites. They are also found to be associated with mafic rocks like diorites which, at some portions have formed hybrid rocks. Quartz- feldspar- granites are the porphyritic rocks that found in the ring complex. The complex intrude the basement rocks of central Nigeria. Structural trends on these rocks suggest that they were controlled by some deep seated structures of the basement. Mineral suite identified include; fayalite, pyroxene, amphibole, k-feldspar, biotite, quartz, iron- oxide and accessory minerals like zircon, apatite, and allanite. Generally, the petrography of these rock samples reveal the presence of a mafic magma which has two pulses (a mafic and felsic pulse) of injection.

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Farag, S., C. Mas, P. D. D. Maizeret, B. Li, and Le Van Hung. "An Integrated Workflow for Granitic-Basement-Reservoir Evaluation." SPE Reservoir Evaluation & Engineering 13, no. 06 (December 8, 2010): 893–905. http://dx.doi.org/10.2118/123455-pa.

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Summary In recent years, energy companies in the Asia Pacific region have focused increasing attention on granitic basement reservoirs, following several new oil and gas discoveries in these complex reservoirs. However, accurate formation evaluation in fractured, crystalline, granitic reservoirs is notoriously difficult. Furthermore, relatively little research has been conducted to understand loggingtool response or pressure-transient behavior, or to develop suitable workflows for formation evaluation in these types of reservoirs. In this paper, we propose a method for integrating various openhole logs, production logs, and well-test data to better evaluate the reservoir potential of fractured granitic formations. Because the wells are either horizontal or highly deviated, this workflow also serves as a primary method of assessing the lateral extent of a reservoir. We include a case study from the region to illustrate the workflow. Image-log interpretation, advanced acoustic measurements, nuclear logs, and production logs with distributed local sensors are combined with well-test data to derive the best possible evaluation of the fracture network around the borehole and the degree of connectivity with the reservoir at large. We also discuss the advantages and limitations of the proposed workflow and set the stage for further work in this complex environment.

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Omosanya, Omosanya. "Alteration of 3 field during the evolution of a polycyclic basement complex." Journal of Geology and Mining Research 5, no. 2 (February 28, 2013): 23–37. http://dx.doi.org/10.5897/jgmr2013.0166.

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Oladapo, M. I., O. O. Adeoye, K. A. Mogaji, and S. Adeoye. "Terrain Conductivity Evaluation of Road Base Integrity in a Basement Complex Environment." Journal of Applied Sciences 8, no. 8 (April 1, 2008): 1548–53. http://dx.doi.org/10.3923/jas.2008.1548.1553.

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Adeoti, Blessing, and Chukwuemeka Tony Okonkwo. "Structural Geology of the Basement Complex Rocks in Iwaraja Area, Southwestern Nigeria." International Letters of Natural Sciences 58 (September 2016): 16–28. http://dx.doi.org/10.18052/www.scipress.com/ilns.58.16.

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The geological and structural evolution assessment of the Basement Complex rocks in Iwaraja area, southwestern Nigeria showed that the basement rocks comprise quartzites and quartz-schists of the Effon Psammite Formation, quartz-mica schists, biotite schists, migmatitic gneisses, granitic gneisses, late and post-tectonic granitic rocks including pegmatites, which have been subjected to two phases of deformation. The first phase is mainly a fabric forming deformation that also led to the development of moderately plunging mineral lineation. No minor fold of this phase was recognized. The second deformation phase gave rise to the development of Iwaraja (ductile) shear zone. Mylonitic foliation is sub-vertical and steeply dipping and while the mineral lineation is sub-horizontal and shallowly plunging. Within granitic gneiss mylonites, the shear zone is characterised by early and late open to tight folds of pegmatite dykes. Adjacent the shear zone, ptygmatic folds of quartzo-feldspathic veins in gneisses and crenulated cleavages that overprinted earlier schistosity surfaces in the quartz-mica schist also characterised this deformation phase. Extensional fractures in the various lithologies generally show bimodal orientations mainly in the WNW-ESE and NW-SE directions, which are nearly perpendicular to the regional metamorphic foliations. These deformation conditions depict structural features that are associated with internal zones of orogenic belts. Within the study area, the structures document late-Precambrian deformation during the closing stages of Pan-African orogenesis.

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Jeong, Sekyoo, Seokjeong Yoon, Sungwoo Kim, Juyeon Jung, Myungho Kor, Kayoung Shin, Chaejin Lim, et al. "Anti-Wrinkle Benefits of Peptides Complex Stimulating Skin Basement Membrane Proteins Expression." International Journal of Molecular Sciences 21, no. 1 (December 20, 2019): 73. http://dx.doi.org/10.3390/ijms21010073.

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The dermal-epidermal junction (DEJ) provides a physical and biological interface between the epidermis and the dermis. In addition to providing a structural integrity, the DEJ also acts as a passageway for molecular transport. Based on the recently reported importance of the DEJ in skin aging, novel peptide derivatives have been tested for their effects on basement membrane (BM) protein expressions in cultured human epidermal keratinocytes. As a result, protein expressions of collagen XVII, laminin and nidogen were stimulated by the test peptide and peptides complex. Further ex vivo evaluation using excised human skin, confirmed that the topical application of the peptides complex significantly increased dermal collagen expression, as well as expressions of collagen XVII and laminin. Interestingly, while the origin of the laminin protein is epidermal keratinocytes, the immunohistochemical staining of skin showed that laminin was only detected in the uppermost layer of the dermis, which suggests a tight assembly of laminin protein onto the dermal side of the DEJ. These results suggest that a peptide complex could improve the structural properties of the DEJ through its ability to stimulate BM proteins. In order to evaluate the anti-wrinkle benefits of the peptide complex in vivo, a clinical study was performed on 22 healthy Asian female volunteers older than 40 years. As a result, significant improvements in skin wrinkles for all of the five sites were observed after two weeks, as assessed by skin topographic measurements. Collectively, these results demonstrate the anti-aging efficacy of the peptides complex.

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Journal articles on the topic 'Basement Complex'

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