Tesi: "Stratigraphic Quaternary"

1

Grun, Rainer Wolfgang. "Contributions to quaternary geochronology". Phd thesis, Canberra, ACT : The Australian National University, 1995. http://hdl.handle.net/1885/145307.

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2

Abbott, James T. "Late Quaternary alluviation and soil erosion in Southern Italy /". Digital version accessible at:, 1997. http://wwwlib.umi.com/cr/utexas/main.

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3

Isler, Ekrem Bursin. "Late quaternary stratigraphic and tectonic evolution of the northeastern Aegean Sea /". Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,147122.

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4

Chung, Yi-tak Teresa. "Quaternary stratigraphy of an offshore borehole from northern Lantau, Hong Kong". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42904730.

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5

Batterson, Martin J. "Quaternary history, palaeo-geography and sedimentology of the Humber River basin and adjacent areas /". Internet access available to MUN users only, 1998. http://collections.mun.ca/u?/theses,57121.

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6

Zhang, Jiafu. "Development and application of luminescence dating to quaternary sediments from China". Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22266628.

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7

Holmes, Jonathan Anthony. "Pliocene and Quaternary environmental change in Kashmir, north-west Himalaya". Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:e9bb6cf8-93a8-4471-9c55-7ed84044dc3c.

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Abstract (sommario):

Late Cainozoic environmental changes in Kashmir (33°30' to 34°30' N: 74°10' to 75°30' E) have been reconstructed using a range of techniques. The sedimentary record in Kashmir consists of a thick (>1000m) basin-fill sequence known as the Karewa group, together with glacial and related sediments in the surrounding mountain flanks. The Karewa sediments are fluviolacustrine in origin and comprise alternations of conglomerates, sands and clayey silts. Work on the lower Karewa formation, which has previously been dated palaeomagnetically to between 4 and 0.4 MaBP, involved the semi- quantitative analysis of clay-mineral assemblages by X-ray diffraction.The clay minerals in the lower Karewa mudstones are interpreted as detrital clays which reflect weathering within Kashmir basin. The analyses showed a change in clay mineralogy between about 2.5 and 2.3MaBP, from abundant kaolinite to abundant smectite. Work on the upper Karewa formation involved field description and mapping of facies, sedimentological analysis, dating using thermoluminescence (TL) and amino-acid racemization, and analysis of ostracod assemblages from lacustrine sediments. Areal restriction of the lake in Kashmir occurred about 0.4MaBP with the rapid uplift of the Pir Panjal Range. Sedimentological data show that aeolian dust formed a major input into the lake. Ostracod assemblages show that the lake itself was cool, shallow, alkaline and had abundant plant macrophytes, The lake drained between 120 and SOkaBP. Stratigraphical, sedimentological and faunal evidence suggests that this was a result of tectonically-induced drainage rather than climatically-induced desiccation. The glacial history of the surrounding mountain flanks was reconstructed by field mapping of glacial sediments and dated using TL and radiocarbon methods. Present and past patterns of glaciation wore assessed by the determination of equilibrium-line altitudes (ELAs), glaciation thresholds (GTs) and cirque aJtitudes. Glaciers extended to 2150 m a.s.l in the Great Himalayan flank and 2600 m a.s.l. in the Pir Panjal. There is evidence for only 2 pre-Holucene advances in Kashmir, the older of which predates 35kaBP. Present patterns of glacierization indicate a SW to NE rise in the height of ELAs and GTs suggesting topographic and precipitation control. An apparent reversal of trends during the past is explained by Quaternary uplift of the Pir Panjal Range.

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8

Dalman, Kurt Alan. "Timing, distribution and climatic implictions of late quaternary eolian deposits : northern Columbia Plateau, WA". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Spring2007/k_dalman_043007.pdf.

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9

Duncan, Catherine Schuur. "Latest Quaternary stratigraphy and seafloor morphology of the New Jersey continental shelf /". Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008320.

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10

Fan, Anchuan, e 范安川. "Quartz OSL dating of quaternary sediments from China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45700187.

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11

張家富 e Jiafu Zhang. "Development and application of luminescence dating to quaternary sediments from China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31242662.

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12

鍾頤德 e Yi-tak Teresa Chung. "Quaternary stratigraphy of an offshore borehole from northern Lantau, Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42904730.

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13

Scott, Sharon. "Quaternary glaciomarine events, Springdale-Hall's Bay area, north-central Newfoundland". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0034/MQ47474.pdf.

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14

Chan, Kin-chung. "The application and significance of sediment colour intensity on the study of offshore quaternary deposits". Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B42577202.

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15

Brown, Kendrick Jonathan. "Late quaternary vegetation, climate, fire history, and GIS mapping of Holocene climates on southern Vancouver Island, British Columbia, Canada". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ52755.pdf.

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16

Bergolc, Melanie. "A paleoenvironmental analysis using fossil insects in late Quaternary deposits in Indiana and Ohio". Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1092940677.

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17

Chui, Wai-hong. "Geology and engineering properties of offshore quaternary sediments in the Yam O reclamation area, Lantau Island". Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B42577561.

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18

Li, Bo. "Development and application of optical dating using quartz and potassium-feldspar from quaternary sediments". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39557212.

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19

Wittmer, Jacalyn M. "Quantitative approaches and applications to the sequence stratigraphy and biodiversity of Pleistocene – Holocene mollusk communities from the Po plain, Italy and San Salvador Island, the Bahamas". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56637.

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Abstract (sommario):

The following chapters presented here use modern ecological data and modern marine systems to evaluate past marine depositional settings and the preservation potential of various environments in the geological record. While the chapters in this dissertation vary in terms of study area, sedimentary systems (carbonate vs. siliciclastic), depositional environment, and organisms, all projects are based on developing and using quantitative models to evaluate the present as a means for understanding the past. Chapter one focuses on the preservation potential of rocky intertidal environments. The rocky intertidal zone is one of the most poorly preserved fossil-rich environments in the geological record. However in most coastal marine habitats today, it is one of the most diversity rich environments. Chapter one also focuses on the analytical advantages of hierarchical sampling of gastropod communities across San Salvador Island, the Bahamas to quantify community and species level preservation potential in rocky shore environments. Chapters two and three are based on the fossil-rich sedimentary deposits from the Po coastal plain in northeastern Italy. These deposits have been widely studied in terms of their sedimentology and stratigraphy, resulting in a highly resolved sequence stratigraphic architecture. The integration of sequence stratigraphy with paleobiology can enhance our understanding of spatiotemporal biotic patterns recorded in the fossil record. Used in conjunction with the highly-resolved stratigraphic framework, biotic patterns can be used to assess depositional cycles and bathymetry through time. Chapter two integrates sequence stratigraphic patterns and paleoecological data to develop bathymetric models across fossiliferous marine successions of the Po coastal plain, Italy. Chapter three evaluates the modern ecological dataset used to derive the bathymetric models. The last chapter also explores water depth distribution for selected taxa recorded in the Quaternary sediments and observed in present-day habitats. The dissertation research explored here demonstrates that modern ecological systems are essential to evaluating past geologic events. Through direct observation and quantitative analysis, I have learned that modern and fossil communities behave differently depending on environment (e.g. energy, salinity, water depth, etc.). These variables affect the distribution of living organisms today and through my research, delineate fossil distributions through time. With these observations, new questions have arisen about the latitudinal variability of rocky intertidal fossil preservation and extrapolating the quantitative bathymetric models to deeper time intervals. These questions will lead to future endeavors and pointedly add to the field of geology and stratigraphic paleobiology.
Ph. D.

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20

Murray-Wallace, Colin Vincent. "Evaluation and application of the amino acid racemisation reaction in studies of quaternary coastal and marine sediments in Australia /". Title page, contents and abstract only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phm9848.pdf.

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21

Owen, Athena Marie. "Tafoni caves in quaternary carbonate eolianites examples from the Bahamas /". Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-05142007-143443.

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22

Pucillo, Kevin. "Quaternary palaeochannel evolution and groundwater movement in the Coleambally Irrigation District of New South Wales". School of Earth and Environmental Sciences - Faculty of Science, 2005. http://ro.uow.edu.au/theses/406.

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The Quaternary alluvial and aeolian sediments underlying the eastern portion of the Riverine Plain have been examined to assess their impact on groundwater access and movement in the Coleambally district. Over 9800 borehole logs from the Coleambally Irrigation Area (CIA) and surrounding districts were digitized using GIS and database software and supplemented with 632 borehole logs from the Department of Land and Water Conservation (Leeton) to form the platform for stratigraphic and groundwater investigations conducted in this study. The borehole data were summarised into two sediment classification schemes, the first to delineate the distribution of palaeochannel sediments and the second to assess to spatial distribution of aquitards and aquifers. A series of detailed cross-sections differentiated between at least four distinct palaeochannel sequences identified within the Upper Shepparton Formation overlying the clay-dominated Lower Shepparton Formation. The two deepest sequences, the new Gumblebogie and Ugobit members, comprise thick (3-10 m), laterally extensive (up to 25 km wide) sheets of coarse sandy alluvium that occur to the north of the CIA at depths between 12 to 35 metres below the surface. These deposits are evidence of highly active alluvial phases on the plain, more vigorous than any since. Slightly higher in the sequence (typically 10-20 m depth) is a thick (2-15 m), laterally extensive (up to 10 km wide) mixed-load sequence (the new Duderbang member), which is stratigraphically disconnected from the deeper sanddominated units. Near-surface palaeochannel deposits, which consist of less extensive (up to 3 km wide) coarse sandy alluvium at depth and a combination of mixed- and bedload sequences closer to the surface, make up the youngest palaeochannel deposits in the area. The size and extent of reserved palaeochannel sequences beneath the study area have decreased markedly since what is interpreted as the mid Quaternary and is probably symptomatic of declining fluvial activity on the Riverine Plain through to the present. The development of source-bordering dunes associated with belts of palaeochannel material in the area was examined using shallow geophysics (GPR), topographic surveys, laser particle size analysis and thermoluminescence dating. Dune building in Contents the area occurred in conjunction with channel activity during the Kerarbury (55-35 ka) and Coleambally (105-80 ka) palaeochannel phases (Page et al., 1996) when sediment supply conditions were favourable, probably due to strongly seasonal discharges draining the southeastern highlands. The presence of stabilising vegetation on the channel margins is believed to have played a key role in the development of dunes in the area, which show poorly developed internal structure. The increased precipitation that enhanced channel discharges must also have sustained dune vegetation. Increased aridity and reduced vegetation approaching and during the LGM appears to have caused the widespread remobilization of dune crests. The complex alluvial and aeolian stratigraphy of the Shepparton Formation strongly influences groundwater movement in the Coleambally district. Piezometric levels show that deeper, highly permeable units (e.g. Ugobit member) in the northern part of the study area act as conduits for the discharge of groundwater, helping to maintain much lower watertables in the north as well as induce groundwater flow from the CIA. ‘Sediment vs depth’ analysis demonstrates that there is limited vertical connection through the thick, clay-dominated sequence of the Lower Shepparton Formation to the highly transmissive sands and gravels of the underlying Calivil Formation. The tendency of the Lower Shepparton Formation to restrict downward leakage is likely to both contribute to the problem of shallow irrigation-induced watertables in the CIA as well as impede efforts to lower watertables by pumping from deeper aquifers. The upper 3 metres of the Shepparton Formation are clay-dominated with a low water storage capacity, causing near-surface watertables to be highly responsive to recharge by surface water. The available data indicate that when piezometric levels fall below this clay-rich zone they are able to absorb short-term increases in recharge due to the higher proportion permeable alluvium in the unsaturated zone.

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23

Glenn, Kriton Campbell. "Sedimentary processes during the Late Quaternary across the Kimberley Shelf, Northwest Australia /". Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phg5584.pdf.

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Abstract (sommario):

Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Geology and Geophysics, 2004.
"February 2004" Includes bibliographical references (leaves 216-227).

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24

Cavas, Matthew P. "THE QUATERNARY GEOLOGY AND SEQUENCE STRATIGRAPHY OF THE LAKE BONNEVILLE DEPOSITS IN THE MATLIN QUADRANGLE, BOX ELDER COUNTY, NORTHWESTERN UTAH". Ohio University / OhioLINK, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1080586528.

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25

Li, Bo, e 李波. "Development and application of optical dating using quartz and potassium-feldspar from quaternary sediments". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39557212.

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26

Bongino, John Daniel Nordt Lee C. "Late quaternary history of the Waco Mammoth site environmental reconstruction and interpreting the cause of death /". Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5047.

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27

Nugent, Courtney A. "Late Quaternary fluvial stratigraphy of the St. Albans archeologic site (46KA27), West Virginia". Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=348.

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Thesis (M.S.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains v, 83 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 63-65).

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28

Hickson, Catherine Jean. "Quaternary volcanism in the Wells Gray-Clearwater area, east central British Columbia". Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27315.

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Basaltic volcanism in the form of small-volume, subaerial and subaqueous eruptions have occurred in the Wells Cray—Clearwater area of east central British Columbia. These eruptions have been dated by the K-Ar method and by relationships to dated glaciations. The oldest known eruption may be as old as 3.2 Ma, but is more likely 2 Ma or less. The youngest eruptions are less than 7560 ± 110 radiocarbon years. The most extensive basalts are valley-filling and plateau-capping flows of the Clearwater unit, which are Pleistocene in age and greater than 25 km³ in volume. The deposition of flows of the Clearwater unit has overlapped at least three periods of glaciation. The interaction of glacial ice and basaltic magma has been recorded in the form of tuyas, ice ponded valley deposits and subglacial mounds (SUGM). In a few place glacial till has been preserved beneath basalt flows. Flows of Wells Gray—Clearwater suite appear to have erupted from vents that are both spatially and temporally separated. The individual eruptions were of low volume (<1km³) and chemically distinct from one another. Major element composition is variable but the lavas are predominantly alkalic. Olivine is the predominant phenocryst phase. Plagioclase and augitic clinopyroxene rarely occur as phenocrysts, but both minerals are ubiquitous in the groundmass. Orthopyroxene was not seen in any of the samples. Flows appear to have erupted with minimal crystal fractionation or crustal contamination. The range of compositions seen in the suite is best explained by a process of partial melting and the progressive depletion of the mantle source by earlier melts. Progressive depletion of the mantle source was coupled with enrichment of parts of the mantle in K as well as some lithophile and siderophile elements. Increasing alkali content may have triggered the highly enriched eruptions of Holocene age that, despite very low degrees of partial melting, were capable of reaching the surface. Overprinting the effects of partial melting are inherited heterogeneities in the source zone of the magmas. Based on whole-rock chemistry the magma source appears to be a highly depleted region similar to that which produces the most depleted mid-ocean ridge basalts (MORB). The zone is, however, capable of producing large volume (≃ 15%) partial melts and has not been isotopically depleted to the same extent as MORB source regions. Isotope analyses of ⁸⁷Sr/⁸⁶Sr, ¹⁴³Nd/¹⁴⁴Nd and whole-rock Pb indicate that the magmas may be derived from a remnant of subducted oceanic lithosphere which has been variously depleted by the prior generation of basaltic melts. Isotopic enrichment above the level seen in MORB's is due in part to crustal contamination. The isotopic results are very different than those obtained from samples erupted through thin, allochthonous crust in the Intermontane Belt and may be explained in part by generation of the magmas in oceanic material which was subducted when allochthonous crust lay against the parautochthonous rocks underlying the Wells Cray—Clearwater area. The alkali olivine basalts of the Wells Cray—Clearwater area have erupted onto a tectonically active surface. A peneplain (erosion surface), formed in Eocene-Miocene time has been uplifted since the Miocene and uplift may be continuing. This uplift is in response to an elevated geothermal gradient which may be due to crustal extension. This crustal extension may be similar to that which occurred in the Eocene. The elevated geothermal gradient and reduced pressures attendant with recent uplift and erosion may have initiated basaltic volcanism in the region, rather than a fixed mantle hot spot as proposed in earlier work.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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29

Muiruri, Veronica Mwihaki. "Late Quaternary diatom and palynomorph stratigraphies and palaeoenvironments of the Koora Graben and Lake Magadi Basin, Kenya Rift Valley". HKBU Institutional Repository, 2017. https://repository.hkbu.edu.hk/etd_oa/461.

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Two sets of cores were recovered from the southern Kenya Rift (Koora and Magadi basins) through the Hominid Sites and Paleolakes Drilling Project and the Olorgesailie Drilling Project. These contain a detailed environmental Quaternary history with records of up to ~1 million years. This period correlates with much of the Olorgesailie Formation record of 1.2 Ma in the Olorgesailie Basin. The Magadi cores reached trachyte at ~ 194 and 133 m with this project focussed on the longer core, MAG14-2A, which includes limestone, zeolitic, laminated and massive clay and silt, massive mud, chert, trona, gravel and sand. The Koora Core (OLO12-1A) extended to depths of 166.14 m and contains laminated and massive diatomites, fine to coarse sands; lime and siliciclastic muds with pumice-rich gravels. The two cores are particularly important because they provide environmental records that help to fill erosional gaps in the history of the Olorgesailie Basin, which includes important evidence for changing hominin cultures and evolution. The high-resolution lacustrine-terrestrial stratigraphies of the two basins have shown how landscapes were transformed because of complex interactions between tectonic and climatic processes. Volcanism also had a significant impact, partially damming lakes at Olorgesailie. Diatoms are present in much of the Koora Basin sequence and large parts of the Magadi sediments. These are dominated by a variety of planktonic Aulacoseira, Cyclotella and Thalassiosira taxa in both basins. Species comprising these genera and other planktonic, benthonic and epiphytic taxa preserve a detailed record of lakes that fluctuated in depth, extent and chemistry. The data document the presence of freshwater and saline lakes as well as wetlands. Diatom transfer functions from the Koora and Magadi basins indicate that these water bodies fluctuated widely in conductivity between ~200 to >20,000 µs cm−1, with pH changing between about 7.5 and 11.5. The palaeolakes also periodically exceeded diatom tolerance limits and intermittently dried out. Pollen are generally lacking in the Koora basin sediments, but deposits in the Magadi core contain common pollen that document a wide range of habitats, including forests, woodlands and grasslands that could have supported the presence of hominins and their activities in the region. Fungal spore data support pollen inferences and indicate periods when large mammals might have been common. The microfossil record shows that there was a broad trend towards more arid conditions in the southern Kenya Rift after about 510 Ka, interrupted by periodic wetter conditions. A major episode of desiccation developed between about 450 Ka to 400 Ka that partially correlates with a period of mammal extinctions and a change from Acheulean to Middle Stone Age toolkits in the Olorgesailie Basin, suggesting that these changes might have been related to environmental conditions at that time.

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Sommerville, Anne A. "The late Quaternary history of Terra Nova National Park and vicinity, northeast Newfoundland". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36180.pdf.

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31

Lee, Kristen M. "Late Quaternary Sea-Level Lowstand Environmetns and Chronology of Outer Saco Bay, Maine". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/LeeKM2006.pdf.

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Chan, Kin-chung, e 陳健忠. "The application and significance of sediment colour intensity on the study of offshore quaternary deposits". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B42577202.

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Chui, Wai-hong, e 徐偉康. "Geology and engineering properties of offshore quaternary sediments inthe Yam O reclamation area, Lantau Island". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B42577561.

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34

Bemis, Sean Patrick 1979. "Moletrack scarps to mountains: Quaternary tectonics of the central Alaska Range". Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/10563.

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Abstract (sommario):

xvi, 121 p. : ill. (some col.), maps (some col.) Also includes two large-scale maps in two separate pdf files. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
Deformation across plate boundaries often occurs over broad zones with relative motions between plates typically accommodated by faults of different styles acting together in a complex system. Collision of the Yakutat microplate within the Alaskan portion of the Pacific-North America plate boundary drives deformation over 600 km away where the Denali fault divides predominantly rigid crustal block motions of southern Alaska from distributed deformation in central Alaska. Quaternary geologic mapping along the Nenana River valley and the Japan Hills of the northern foothills of the Alaska Range defines zones of Quaternary thrust faulting recorded in the progressive deformation of Pleistocene fluvial terraces. I use topographic profiles of these terraces and paleoseismic trenching of fault scarps to characterize the Quaternary activity and constrain the subsurface geometry of these faults. Radiocarbon and cosmogenic exposure dating methods provide age control on the stratigraphy in the trenches and landforms offset by these faults. These observations define a 1-1.5 mm/yr slip rate for the Gold King fault which changes laterally from a north-vergent thrust into a north and south vergent thrust wedge that uplifts the Japan Hills. Along the Nenana River valley, the progressive deformation of Pleistocene surfaces defines a north-vergent critically-tapered thrust wedge. The geometry of progressive uplift and folding requires a near planar, south-dipping basal thrust fault with two major north-dipping backthrusts. All three faults were active simultaneously on a scale of 10 4 yrs with slip rates of 0.25-1 mm/yr, until the late Pleistocene when we infer the retreat of glacial ice from the main axis of the Alaska Range caused a change in thrust wedge dynamics. I use the orientation of Quaternary deformation north of the Denali fault to show that strain is highly partitioned and establish geologic constraints on the regional horizontal stress orientation. North of the Denali fault, fault-normal principal shortening accommodates 3-5 mm/yr of strain transfer across the Denali fault system. Two appendices contain additional results of paleoseismic trenching and neotectonic investigations across 4 active faults near the Nenana River. This dissertation includes previously unpublished co-authored material.
Committee in charge: Ray Weldon, Chairperson, Geological Sciences; Joshua Roering, Member, Geological Sciences; David Schmidt, Member, Geological Sciences; Douglas Kennett, Outside Member, Anthropology

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35

Harding, Rachel. "Evolution of the giant southern North Sea shelf-prism : testing sequence stratigraphic concepts and the global sea level curve with full-three dimensional control". Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/evolution-of-the-giant-southern-north-sea-shelfprism-testing-sequence-stratigraphic-concepts-and-the-global-sea-level-curve-with-fullthree-dimensional-control(e2837da3-6d8b-4e07-b9a0-0af836e8ee71).html.

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This thesis investigates the utility of sequence stratigraphy on a regional scale and the control of eustacy on basin infill in unprecedented detail. To achieve this, the thesis utilises a wealth of data, including a continuous 3D seismic MegaSurvey dataset covering 55,000 sq. km, combined with state of the art seismic interpretation software to interpret the basin infill of the Late Cenozoic southern North Sea. The prograding shelf-prism clinoforms of the Late Cenozoic are calibrated to high density borehole penetrations, high resolution chronostratigraphy and climate proxies. The chronostratigraphic control enables a correlation of geomorphology, seismic architectures and seismic facies with full 3D control to the global sea level curve, which enables an evaluation of the impact of eustatic change on sequence development. The control of eustacy and the limitations of sequence stratigraphy are highlighted by: 1) Investigating the regional expression of chronostratigraphically calibrated seismic units, which are linked to the global sea level curve. This was carried out by mapping across the region, the dominance of oblique or sigmoidal clinoform types and seismic features such as iceberg scours, terrestrial channels and submarine fans in order to evaluate the lateral variation of depositional systems and accommodation. 2) Investigating sediment partitioning basinwards of the shelf edge and how deposition basinwards can be predicted via observations of seismic facies and architecture. This was achieved by focusing on specific seismic architectures of forced regressive slope clinoforms and deep water sedimentary systems and the link updip to the shelf within the highly constrained chronostratigraphic framework. The thesis results suggest that sequence stratigraphic models do not represent lateral variation well or integrate other allocyclic forcings on sequence development. A holistic and observation based approach to understanding basin infill and recognising the importance of sediment supply, pre-existing geomorphology, process type of the feeder system, differential subsidence, as well as eustacy, is imperative.

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36

Pietsch, Timothy J. "Fluvial geomorphology and late quaternary geochronology of the Gwydir fan-plain". Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060720.153247/index.html.

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37

Gong, Zhijun, e 龚志军. "Application of optical dating to late quaternary uplift and thrust activity in the northern piedmont of Tian Shan, China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hdl.handle.net/10722/193394.

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Tian Shan is one of the most important orogenic belts in central Asia. It has been reactivated as a result of the Cenozoic India-Eurasia collision. Dating of the late Cenozoic tectonic deformation of Tian Shan and its piedmonts is important for understanding the mountain building as well as evaluating seismic hazards in the region. This study is focused on the applications of optical dating to the late Quaternary uplift and thrust activity along Manas River, in the northern piedmont of the Tian Shan, China. The sediments on river terraces were dated with optical dating. The elevations were measured with the kinematic global position system (GPS). The results suggest that two phases can be identified according to the significantly different river incision rates. One phase was from ~20 ka to ~4.8 ka, with a much slower incision rate of ~ 2.2 ± 0.6 mm/yr. The other phase was from ~4.8 ka to present, with a faster incision rate of ~ 13.5 ± 0.6 mm/yr. The accelerated incision rate of Manas River was mainly attributed to the tectonic forces, suggesting that the tectonic uplift was significantly intensified since ~4.8 ka in the northern piedmont of Tian Shan. The study region has suffered from multiple thrust activities during the late Quaternary, which led to the intensive deformations of the river terraces. By studying the deformed terraces, I evaluated the timing of the past thrust activities as well as the vertical slip rate of the thrust faults. The results demonstrated that the thrust activity intensified during the late Holocene, as manifested by the more frequent thrust activities and higher vertical slip rates. Both quartz and potassium feldspar can be as dosimeters for optical dating of sediments. However, quartz OSL is sometimes seriously impeded with problems such as very dim signals and insufficient bleaching problems. K-feldspar has attractive advantages over quartz, despite of problem of anomalous fading. K-feldspar was explored in this study, by investigating the relationship between the infrared stimulated luminescence (IRSL) and blue light stimulated luminescence (BLSL) signals. For IRSL and BLSL at 60 °C, it was suggested that most of the IRSL could be bleached by blue light (BL), while the BLSL could only be partially bleached by infrared (IR) stimulation. Besides, the fast and medium components of BLSL were mainly associated with the IRSL. If IR stimulation temperature was raised from 60 to 200 °C, at least two portions of the IRSL signals at 200 °C were observed. One portion could be bleached by BL at 60 °C and the other portion was hardly bleached by BL at 60 °C. Dating of K-feldspar from the various signals provided cross-checking for the reliability of quartz OSL for dating sedimentary samples.
published_or_final_version
Earth Sciences
Doctoral
Doctor of Philosophy

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38

Mok, Wing-yan Connie, e 莫穎恩. "Integrated sedimentological, geophysical and geotechnical study of inner shelf sediments in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B35675172.

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39

De, Deckker P. "Australian Quaternary studies : a compilation of papers and documents submitted for the degree of Doctor of Science in the Faculty of Science, University of Adelaide /". Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09SD/09sdd299.pdf.

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40

Maselli, Vittorio <1982&gt. "The stratigraphic record of the quaternary sea level fluctuations and the impact of the post-glacial sea level rise (Termination I) in the Adriatic basin (Mediterranean sea)". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3860/.

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The modern stratigraphy of clastic continental margins is the result of the interaction between several geological processes acting on different time scales, among which sea level oscillations, sediment supply fluctuations and local tectonics are the main mechanisms. During the past three years my PhD was focused on understanding the impact of each of these process in the deposition of the central and northern Adriatic sedimentary successions, with the aim of reconstructing and quantifying the Late Quaternary eustatic fluctuations. In the last few decades, several Authors tried to quantify past eustatic fluctuations through the analysis of direct sea level indicators, among which drowned barrier-island deposits or coral reefs, or indirect methods, such as Oxygen isotope ratios (δ18O) or modeling simulations. Sea level curves, obtained from direct sea level indicators, record a composite signal, formed by the contribution of the global eustatic change and regional factors, as tectonic processes or glacial-isostatic rebound effects: the eustatic signal has to be obtained by removing the contribution of these other mechanisms. To obtain the most realistic sea level reconstructions it is important to quantify the tectonic regime of the central Adriatic margin. This result has been achieved integrating a numerical approach with the analysis of high-resolution seismic profiles. In detail, the subsidence trend obtained from the geohistory analysis and the backstripping of the borehole PRAD1.2 (the borehole PRAD1.2 is a 71 m continuous borehole drilled in -185 m of water depth, south of the Mid Adriatic Deep - MAD - during the European Project PROMESS 1, Profile Across Mediterranean Sedimentary Systems, Part 1), has been confirmed by the analysis of lowstand paleoshorelines and by benthic foraminifera associations investigated through the borehole. This work showed an evolution from inner-shelf environment, during Marine Isotopic Stage (MIS) 10, to upper-slope conditions, during MIS 2. Once the tectonic regime of the central Adriatic margin has been constrained, it is possible to investigate the impact of sea level and sediment supply fluctuations on the deposition of the Late Pleistocene-Holocene transgressive deposits. The Adriatic transgressive record (TST - Transgressive Systems Tract) is formed by three correlative sedimentary bodies, deposited in less then 14 kyr since the Last Glacial Maximum (LGM); in particular: along the central Adriatic shelf and in the adjacent slope basin the TST is formed by marine units, while along the northern Adriatic shelf the TST is represented by costal deposits in a backstepping configuration. The central Adriatic margin, characterized by a thick transgressive sedimentary succession, is the ideal site to investigate the impact of late Pleistocene climatic and eustatic fluctuations, among which Meltwater Pulses 1A and 1B and the Younger Dryas cold event. The central Adriatic TST is formed by a tripartite deposit bounded by two regional unconformities. In particular, the middle TST unit includes two prograding wedges, deposited in the interval between the two Meltwater Pulse events, as highlighted by several 14C age estimates, and likely recorded the Younger Dryas cold interval. Modeling simulations, obtained with the two coupled models HydroTrend 3.0 and 2D-Sedflux 1.0C (developed by the Community Surface Dynamics Modeling System - CSDMS), integrated by the analysis of high resolution seismic profiles and core samples, indicate that: 1 - the prograding middle TST unit, deposited during the Younger Dryas, was formed as a consequence of an increase in sediment flux, likely connected to a decline in vegetation cover in the catchment area due to the establishment of sub glacial arid conditions; 2 - the two-stage prograding geometry was the consequence of a sea level still-stand (or possibly a fall) during the Younger Dryas event. The northern Adriatic margin, characterized by a broad and gentle shelf (350 km wide with a low angle plunge of 0.02° to the SE), is the ideal site to quantify the timing of each steps of the post LGM sea level rise. The modern shelf is characterized by sandy deposits of barrier-island systems in a backstepping configuration, showing younger ages at progressively shallower depths, which recorded the step-wise nature of the last sea level rise. The age-depth model, obtained by dated samples of basal peat layers, is in good agreement with previous published sea level curves, and highlights the post-glacial eustatic trend. The interval corresponding to the Younger Dyas cold reversal, instead, is more complex: two coeval coastal deposits characterize the northern Adriatic shelf at very different water depths. Several explanations and different models can be attempted to explain this conundrum, but the problem remains still unsolved.

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41

Waters, Michael R. "The Geoarchaeology of Whitewater Draw, Arizona". University of Arizona Press (Tucson, AZ), 1986. http://hdl.handle.net/10150/615943.

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42

Principaud, Mélanie. "Morphologie, architecture et dynamique sédimentaire d'une pente carbonatée moderne : le Great Bahama Bank (Bahamas)". Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0301/document.

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Une analyse de données de sondeur multifaisceaux, de sondeur de sédiments (Chirp) et de sismique multitraces, présente la morphologie et la dynamique sédimentaire actuelle ainsi que l’évolution architecturale et stratigraphique du Néogène-Quaternaire opérant le long d’une marge leeward, au nord-ouest du Great Bahama Bank. L’analyse morpho-bathymétrique révèle un talus dominé par de la boue aragonitique, et une grande variété de structures sédimentaires, liées à des processus hydrodynamiques diversifiés. Les courants de density cascading associés aux courants de marée et aux vents d’est représentent les mécanismes de transports édimentaire dominant le long de la marge. La zone de Bimini présente localement un talus court et abrupt,stabilisé en bordure de plate-forme par une barrière récifale, ce qui limite l’export off-bank de sédiments.L’architecture stratigraphique montre une évolution complexe du talus au cours du Néogène. La fin du Paléogène est marquée par un talus continu aggradant détaché de la plate-forme par un escarpement sur faille. Ilpasse à un système très peu incliné de type slope-apron, attaché à la plate-forme au Miocène et se termine par un système en accrétion fortement incliné au Pléistocène. Bien que les dépôts de talus soient dominés par de la boue, ils présentent des variations latérales rapides du Sud au Nord tout au long du Néogène (< 30 km) avec la mise en place de tabliers turbiditiques, de nappes de débrites, et de larges Mass Transport Complexes. Ces faciès interagissent depuis le Langhien avec le Santaren Drift qui s’étend et migre progressivement le long du talus jusqu’à aujourd’hui. Le maximum d’empiétement des contourites se produit au Pliocène supérieur et coïncide avec une réorganisation océanographique globale ainsi que des changements climatiques majeurs dans l’hémisphère nord liés à la fermeture de la Central American Seaway
An analysis of multi-beam echo sounder, sub-bottom profiler (Chirp) and multichannel seismic,highligths the present-day sedimentary dynamics and the Neogene-Quaternary architectural and stratigraphicevolution along the northwestern leeward margin of the Great Bahama Bank.The morpho-bathymetric analysis reveals an aragonite mud-dominated slope, and a broad spectrum ofsedimentary structures, related to various hydrodynamic processes. The density cascading currents associatedwith tidal currents and prevailing easterly winds correspond to the dominant transport mechanisms operatingalong the margin. The Bimini area displays a short and steep slope, stabilized at shelf edge by rimmed reefalbarrier, which constrains the off-bank export of materials.The stratigraphic architecture shows a complex evolution of the slope during the Neogene. The end ofthe Paleogene is marked by a continuous aggrading slope detached from the shelf by a fault escarpment. It passesinto a low angle slope-apron attached to the platform in the Miocene, and ends with an accretionary system witha steepened slope in the Pleistocene. Although the slope deposits are mud-dominated, they show rapid lateralvariations (< 30 km) from South to North throughout the Neogene with the establishment of turbidite aprons,debrite layers and large Mass Transport Complexes. These facies interact since the Langhian with the SantarenDrift which gradually extends and migrates along the slope until today. The maximum extent of the drift occursduring the upper Pliocene and coincides with a global oceanographic reorganization and major climate changesin the northern hemisphere, related to the closure of the Central American Seaway

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43

Wazi, Nandefo. "Le crétacé du Roumois (Vallée de l'Oison) et le tertiaire-quaternaire des régions voisines de la basse vallée de la Seine : stratigraphie et tectonique". Rouen, 1988. http://www.theses.fr/1988ROUES030.

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Etude de la série crétacé du Roumois à partir de l'analyse lithostratigraphique de nombreuses coupes. La définition précise des formations sédimentaires de l'Aptien-Albien au Coniacien-Santonien est étagée par une étude biostratigraphique et séquentielle qui permet d'individualiser dix formations. Inventaire des témoins éocènes à pléistocènes de la région de la Basse Seine. Détermination du style tectonique du plateau du Roumois à partir d'une cartographie détaillée et d'une analyse structurale d'anciens documents géologiques et géophysiques. On propose une interprétation reghmatique en décrochements potentiels. Chronologie des évènements tectono-sédimentaires ayant affecté la région

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44

Mowbray, Leslie Allen. "Quaternary Chronology and Stratigraphy of Mickey Springs, Oregon". Thesis, Portland State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=1606164.

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Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved.

Three morphologies of silica sinter deposition have been identified at Mickey Springs. These are (1) well-sorted, fine-grained sandstone with ripple marks, cross beds and preserved root casts, to poorly-sorted conglomerate of primarily basalt clasts, both cemented by coeval silica deposition, (2) large depressions (12-32 m diameter) rimmed with sinter, characterized by fine silt and clay blanketing a sinter apron and infilling the central depression, and (3) quaquaversal sinter mounds identified by outcropping pool-edge sinter typically surrounding a shallow depression of loose sediment.

Silica-cemented sandstone and conglomerate were the first features formed by coeval hydrothermal processes at the site, and were emplaced prior to 30 kya as suggested by structural and stratigraphic relationships. Structure between two interacting fault tips may have constrained the extent of silica cementation. By 30 kya, a left-stepping fault oriented roughly north/south further constrained the near-surface permeable zone. TL dates from sediment stratigraphically below and above sinter aprons around mounds and depressions (former spring vents) indicate sinter deposition between 30 and 20 kya. Location of these features was dictated by development of the left-stepping fault. As pluvial Lake Alvord filled at the end of the Pleistocene, lake sediment filled most vents, which were largely inactive, with fine-grained silt and clay.

Today, hydrothermal activity persists in two modes: (1) The current high-temperature springs, steam vents and mudpots concentrated in a 50 x 50 m area south of the sinter mounds and depressions, and (2) scattered springs and steam vents that exploit previous permeable pathways that once provided the hydrothermal fluid which precipitated the sinter aprons. Currently there is no active silica sinter deposition at Mickey Springs.

Structures and stratigraphic relationships identified through this study favor a transport-limited and structurally controlled model of fluid transport. Sinter deposition is determined to have occurred before the most recent highstand of pluvial Lake Alvord. A climate driven model, where groundwater recharge from pluvial Lake Alvord circulates to a deep heat source and enhances spring discharge, is not supported by these findings, as no evidence was found for sinter precipitation after the drying of the lake. Future studies of other hydrothermal systems in the Basin and Range may reveal that permeable pathways along local structures are the primary drivers in this region.

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45

Mowbray, Leslie Allen. "Quaternary Chronology and Stratigraphy of Mickey Springs, Oregon". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2637.

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Abstract (sommario):

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. Three morphologies of silica sinter deposition have been identified at Mickey Springs. These are (1) well-sorted, fine-grained sandstone with ripple marks, cross beds and preserved root casts, to poorly-sorted conglomerate of primarily basalt clasts, both cemented by coeval silica deposition, (2) large depressions (12-32 m diameter) rimmed with sinter, characterized by fine silt and clay blanketing a sinter apron and infilling the central depression, and (3) quaquaversal sinter mounds identified by outcropping pool-edge sinter typically surrounding a shallow depression of loose sediment. Silica-cemented sandstone and conglomerate were the first features formed by coeval hydrothermal processes at the site, and were emplaced prior to 30 kya as suggested by structural and stratigraphic relationships. Structure between two interacting fault tips may have constrained the extent of silica cementation. By 30 kya, a left-stepping fault oriented roughly north/south further constrained the near-surface permeable zone. TL dates from sediment stratigraphically below and above sinter aprons around mounds and depressions (former spring vents) indicate sinter deposition between 30 and 20 kya. Location of these features was dictated by development of the left-stepping fault. As pluvial Lake Alvord filled at the end of the Pleistocene, lake sediment filled most vents, which were largely inactive, with fine-grained silt and clay. Today, hydrothermal activity persists in two modes: (1) The current high-temperature springs, steam vents and mudpots concentrated in a 50 x 50 m area south of the sinter mounds and depressions, and (2) scattered springs and steam vents that exploit previous permeable pathways that once provided the hydrothermal fluid which precipitated the sinter aprons. Currently there is no active silica sinter deposition at Mickey Springs. Structures and stratigraphic relationships identified through this study favor a transport-limited and structurally controlled model of fluid transport. Sinter deposition is determined to have occurred before the most recent highstand of pluvial Lake Alvord. A climate driven model, where groundwater recharge from pluvial Lake Alvord circulates to a deep heat source and enhances spring discharge, is not supported by these findings, as no evidence was found for sinter precipitation after the drying of the lake. Future studies of other hydrothermal systems in the Basin and Range may reveal that permeable pathways along local structures are the primary drivers in this region.

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46

Martillo, Bustamante Carlos. "Enregistrements stratigraphiques des cycles glacio-eustatiques et de la déformation durant le Pléistocène le long de la marge centrale d’Équateur : exploitation des données de la campagne ATACAMES". Thesis, Nice, 2016. http://www.theses.fr/2016NICE4020/document.

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L’objectif de cette étude est de contraindre les déformations au cours du Pléistocène d'une marge active à partir de l’analyse sismo-stratigraphique des sédiments conservés sur la plate-forme et la pente supérieure, le long de la marge centrale d’Equateur. A partir les données de sismique haute résolution et de carottage collectées pendant l'expédition Atacames (2012), plusieurs bassins ont été identifiés. La répartition latérale et de la succession des séquences T-R dans ces bassins montrent une distribution complexe des sédiments dans le temps et l'espace. Ce travail montre que, le long des marges actives, l’analyse sismo-stratigraphique de l’enregistrement des séquences liées aux cycles eustatiques du Pléistocène est un outil très puissant. A l'échelle locale, la subduction de seamounts perturbe et renforce l'effet de déformation régionale de la ride de Carnegie
The aim of this study is to constrain recent deformation and stratigraphic evolution of an active margin, using sismo-stratigraphic analysis of Pleistocene sediment preserved on the margin shelf and upper slope along of the Central Ecuadorian margin. From the extensive geophysical and sedimentological investigations carried out during the ATACAMES expedition (2012), we are identified serveral basins in the Ecuadorian margin. A detailed analysis of the thickness, the lateral distribution and stacking patterns in these basins show a complex distribution of sediments in time and space. The seismic-sequence stratigraphy analysis related to eustatic cycles of the Pleistocene shows a regional regional unconformity at the base (1782-Ka as minimum age), which can correspond to the signature of the beginning of the Carnegie ridge collision

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47

Stoner, Joseph Stephen. "Magnetic properties and paleointensity records frome late quaternary Labrador sea sediments = Propriétés magnétiques et enregistrements de paléointensité des sédiments du quaternaire récent de la mer du Labrador /". Thèse, Chicoutimi : Montréal : Université du Québec à Chicoutimi ; Université du Québec à Montréal, 1995. http://theses.uqac.ca.

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48

Crawford, Kevin A. "The Quaternary Stratigraphy of the Northwind Ridge, Arctic Ocean". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1284698703.

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49

Butcher, J. A. "Seismic stratigraphy of shallow water Quaternary sediments around the UK". Thesis, Bangor University, 1997. https://research.bangor.ac.uk/portal/en/theses/seismic-stratigraphy-of-shallow-water-quaternary-sediments-around-the-uk(0103ae6b-808e-491e-b207-74e648b5ddee).html.

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50

Cousineau, Lyssa A. "Stratigraphy of Quaternary Dunes by Sand Mineralogy and Pedogenic Features, Los Osos, California". DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/827.

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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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