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The stratigraphy of the Platteville formationBays, Carl Andrew, January 1937 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1937. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Stratigraphy of Quaternary Dunes by Sand Mineralogy and Pedogenic Features, Los Osos, CaliforniaCousineau, Lyssa A 01 July 2012 (has links) (PDF)
The goal of this study was to assess mineralogy and pedogenic features of sand dunes in a stratigraphic sequence. The purpose was to determine whether these features significantly differ to reflect age differences with depth within the sequence. This study was conducted in Montaña de Oro State Park, located on the central Californian coast eighteen kilometers northwest of San Luis Obispo in San Luis Obispo County.
Samples were collected from the vertical exposure of one dune face by stratified random sampling at 1.0-m vertical intervals. Particle size distribution was determined through particle-size analysis by hydrometer and sieve. Electrical conductivity and pH were determined using a 1:1 soil/water paste. Total soil carbon and nitrogen contents were determined by combustion. Pedogenic iron oxides were extracted by ammonium oxalate in the dark and citrate-bicarbonate-dithionite, and then quantified by flame atomic absorption spectrometry. Sand mineralogy of fifteen thin sections was analyzed by polarized light microscopy. Grain counts quantified the sand mineralogy of the thin sections.
Total carbon significantly decreases with soil depth and age reflecting modern development of soil at 0 to 1 meters within the stratigraphic sequence. Certain morphologic and mineralogic features, including an increase in nitrogen content and the presence of fossilized fungal hyphae, suggest that a buried A horizon may be preserved 9 to 10 meters below the crest of the modern dune complex. Using relative dates compiled from previous research, it was determined that the soil at 9 to 10 meters depth was developed 15-ka to 30-ka after sand deposition during a eustatic sea level lowstand. The presence of fossils in general suggests that the ancient soil was rapidly covered.
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The sedimentology and uranium mineralization of the Beaufort Group in the Beaufort-West - Fraserburg - Merweville Area, Cape ProvinceKubler, Markus 02 July 2015 (has links)
The sediments of the lower part of the Beaufort Group
(Permian) consist of mudstones, siltstones, fine- to very
Fine-grained sandstones and small amounts of intraformational
conglomerate. The mudstones are generally a
brownish-purple colour, and are massive. The siltstones
are generally greyish-green coloured, and are sometimes
ripple cross-laminated. The sandstones vary in colour
from green to grey. horizontally-bedded, trough cross bedded
and ripple cross-laminated sandstone subfacies
were recognized. All the sandstones found in the area
studied may be described as fine- to very fine-grained,
moderately sorted, arkosic wackes.
The stratigraphic interval studied was found to have a
Thickness of about 850 m. No readily mappable subdivisions
were found. The sandstone to stltstone and mudstone ratio
for the stratigraphic interval is about 1:4.
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Palaeomagnetic investigations of Early and Middle Pleistocene sediments in East Anglia, UKHallam, David Frank January 1995 (has links)
No description available.
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Significance of the palynology and organic facies of the Abu Gabra no.1 well with respect to the petroleum geology of the Abu Gabra Field, SudanBabikir, Adil Elsiddik January 1997 (has links)
No description available.
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The structure and kinematic history of the Walls Boundary Fault in ShetlandConroy, David January 1996 (has links)
No description available.
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Stratigraphy Pennsylvanian, Amsden formation, southwestern MontanaKuenzi, Laurence M. January 1951 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1951. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 44-45).
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Stratigraphic Architecture and Characterization of a Neoproterozoic Continental Slope System, Windermere Supergroup, East-Central British Columbia, CanadaRuso, Simona 13 September 2021 (has links)
At the Castle Creek study area, exceptionally well exposed strata of the Isaac Formation (Neoproterozoic Windermere Supergroup) crop out over a strike length of 4 km. This ~ 1 km-thick succession of continental slope deposits consist of six channel complexes (ICC1-ICC6) composed of three main architectural elements: mass transport deposits (MTDs), channel, and overbank deposits. Together, these elements stack in a repeating and systematic pattern that illustrates periodic forcing on the system related to the combined effect of long- and short-term changes in relative sea level that controlled the development of the continental shelf, and ultimately, the make up of the sediment resedimented into the deep-marine system. Understanding these stacking patterns in ancient slope systems and the conditions under which they formed, is important for assessing regional and potentially global changes in ancient climate and eustasy.
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Structure and influence of the Tillamook Uplift on the stratigraphy of the Mist area, OregonKadri, Moinoddin Murtuzamiya 01 January 1982 (has links)
Fifty three sedimentary samples were analyzed for their minor and trace element concentrations utilizing instrumental neutron activation analysis. Concentrations of Na, K, La, Sm and Sc, and their ratios appear to establish significant trends. The data suggest a major break from a granitic-metamorphic provenance and a volcanic component dominated provenance between the Cowlitz and Keasey Formations respectively. The provenance of the Astoria Formation indicates the presence of flood basalts.
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Stratigraphy and architecture of a coarse-grained deep-water system within the Cretaceous Cerro Toto formation, Silla Syncline area, southern ChileBozetti, Guilherme January 2017 (has links)
The Upper Cretaceous Cerro Toro Formation, southern Chile, is characterised by thinbedded turbidites that envelope a series of coarse-grained, confined slope complex systems, interpreted as part of the Lago Sofia Member. This deep-water slope system overlies basin floor sheets of the Punta Barrosa Formation, and is overlain by the sand-filled slope channels of the Tres Pasos Formation. Particularly distinctive beds, known as TEDs (transitional event deposits), are up to 40 m thick, laterally extensive, have prominent fluted bases, and have a vertical fabric starting with (1) a thin, inversely-graded, clast-supported base; then (2) a normally-graded and clastsupported interval; (3) an increasingly sand and clay matrix-supported conglomerate, with (4) a progressive upwards increase in matrix and normally grading, both in the floating gravel clast and matrix grain sizes, towards the top; and (5) a co-genetic sandstone on top. In the Cerro Toro formation, these TEDs tend to occur as multiple beds in the initial phases of deposition of each channel complex system. The TEDs are highly aggradational, slightly more amalgamated in the channel-axis, and more layered towards the margins. The fabric of these spectacular event beds is described in some detail from measured sections, combined with petrographic analysis and high-resolution field mapping. The 4 km x 200 m channel systems are contained within topographically irregular bathymetric lows that formed sediment pathways, interpreted to be either the result of slope deformation, or contained by poorly preserved, tectonically disrupted or slumped external levee. Syn-sedimentary tectonism is interpreted to be responsible for sharp changes in the system's architecture from channels to ponds, marked by a sharp change in lithofacies from dominantly conglomerates to dominantly sandstones. A refined architectural analysis is proposed, focusing on the recurrent pattern of at least 5 cycles of conglomerate-filled channel systems – ponded sheet sandstones.
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