Tesi: "Geology, 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

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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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

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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5

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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6

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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7

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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8

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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9

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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10

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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11

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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12

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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13

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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14

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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15

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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16

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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17

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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18

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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19

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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20

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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21

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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22

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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23

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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24

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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Abstract (sommario):

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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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

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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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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27

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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28

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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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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30

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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31

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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32

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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33

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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34

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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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

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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37

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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38

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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39

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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40

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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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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41

Rose, Robert Vaughan. "Quaternary geology and stratigraphy of North Westland, South Island, New Zealand". Thesis, University of Canterbury. Geological Sciences, 2011. http://hdl.handle.net/10092/6474.

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Abstract (sommario):

Infrared stimulated luminescence ages are presented from the North Westland region, West Coast, South Island, New Zealand. These ages span much of the last interglacial-glacial cycle from 123.3 ± 12.7 ka to 33.6 ± 3.6 ka. Coverage is extended to c. 14 ka via cosmogenic isotope dating. A new Quaternary stratigraphy and Marine Isotope Stage correlation is proposed for the on-shore glacial-interglacial fluvioglacial, fluvial and marine terrace sequence. The new model incorporates previously published luminescence and radiocarbon ages. It necessitates reinterpretation of the evolution of the climate in North Westland for the period from 123 ka to 14 ka. Reinterpretation of fossil pollen and plant macrofossil records implies a period of probable near-interglacial climate in North Westland during the early to middle portion of Marine Isotope Stage 3. It also implies the presence in North Westland of raised marine terraces dating from this Isotope Stage. In addition it is concluded that during the period from c.60 ka to c.50 ka podocarp dominated forest was widespread in the lowland portion of Westland. Between Okarito and Westport Dacrydium cupressinum and Nestegis were ubiquitous components of this forest. This finding aligns the Marine Isotope Stage 3 climate of North Westland nicely with that of other parts of New Zealand where good records exist for this period.

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42

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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43

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

Testo completo

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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44

Shi, Zhong. "Late Quaternary stratigraphy and recent sedimentation in the Dyfi Estuary, Wales". Thesis, Aberystwyth University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308183.

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45

Langford, Harry. "Sedimentological, palaeogeographical and stratigraphical aspects of the Middle pleistocene geology of the Peterborough area, eastern England". Thesis, Anglia Ruskin University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326053.

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46

Mabry, Jonathan Blum. "Alluvial cycles and early agricultural settlement phases in the Jordan Valley". Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/186086.

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Abstract (sommario):

The parallel development of archaeology and Quaternary geology in several regions of the world is reviewed, and common problems in dating and correlating alluvial sequences are discussed. Buried archaeological remains and radiometric dates provide a chronological framework for the sequence of Late Quaternary alluvial deposits in the central Jordan Rift. While previous studies emphasized a simple, two-stage model of Late Quaternary alluvial deposition, regional comparisons of the geomorphological contexts of archaeological sites of different ages indicate complex, multiple depositional and erosional cycles. These cycles were influenced by tectonism, climatic changes, human land use, and natural geomorphic thresholds, sometimes in combination. The stratigraphy and chronology of early agricultural settlements in the valley are summarized, and investigations at a protohistoric agricultural town are described. Major regional shifts in prehistoric and protohistoric patterns of agriculture and settlement are interpreted in terms of the impacts of changes in alluvial regimes. These correlations have implications for models of agricultural origins, and the stability and resilience of sedentary settlements in dry lands.

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47

Finkelstein, Kenneth. "The late quaternary evolution of a twin barrier-island complex, Cape Charles, Virginia (stratigraphy, sedimentology, Wisconsinan, sea-level highstand)". W&M ScholarWorks, 1986. https://scholarworks.wm.edu/etd/1539616644.

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Abstract (sommario):

A total of 68 vibra-cores and 14-box cores in conjunction with high-resolution seismic records are used to describe the late Quaternary development of a twin-barrier island complex. Based on the stratigraphy, radiocarbon dates, and microfossils, a transgressive outer Holocene and inner Pleistocene barrier island complex are recognized. The two subaerial sub-parallel barriers are a result of separate marine transgressions that occurred before and after late Wisconsin glaciation. Pollen assemblages and ten radiocarbon dates from the lagoonal sediments below the older island concur on a date of approximately 30,000 years B.P., hence a probable mid-Wisconsinan age for the overriding barrier island. The uncertainty surrounding a sea level near today's position 30,000 years ago is not unnoticed; neotectonics may be an important consideration in this apparent rise in sea-level. Holocene sediments deposited in the backbarrier environment show a general shallowing and fining upward sequence. The Holocene stratigraphic sequence indicates a narrowing of the backbarrier region, a decrease in the tidal prism, and an increase in marsh and tidal flat infilling associated with calmer water conditions. Most backbarrier sediments are introduced through tidal inlets. Despite Holocene, backbarrier deposits greater than 8 meters thick, only 2 meters may be preserved below 75-100 cm thick nearshore sands in some areas. Inlet fill deposits will not be preserved. However inner barrier sands and lower Holocene backbarrier sands and muds have a strong preservational potential. The stacking of transgressive barrier deposits, albeit those from different transgressions, may provide a stratigraphic oil trap.

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48

Sellén, Emma. "Quaternary paleoceanography of the Arctic Ocean : A study of sediment stratigraphy and physical properties". Doctoral thesis, Stockholms universitet, Institutionen för geologi och geokemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-30895.

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Abstract (sommario):

A Quaternary perspective on the paleoceanographic evolution of the central Arctic Ocean has been obtained in this PhD thesis by studying sediment cores from all of the Arctic’s major submarine ridges and plateaus. The included cores were mainly recovered during the Healy-Oden Trans-Arctic expedition in 2005 and the Lomonosov Ridge off Greenland expedition in 2007. One of the main thesis objectives is to establish whether different sediment depositional regimes prevailed in different parts of the central Arctic Ocean during the Quaternary and, if so, establish general sedimentation rates for these regimes. This was approached by dating key cores using the decay of the cosmogenic isotopes 10Be and 14C, and through stratigraphic core-to-core correlation using sediment physical properties. However, the Arctic Ocean sea ice complicated the use of 10Be for dating because a solid sea ice cover prevents the 10Be isotopes from reaching the seafloor, resulting in too old ages. Dating using 14C is also complicated due to uncertain marine reservoir age corrections in the central Arctic Ocean. The core-to-core correlations show five areas with different depositional regimes; the northern Mendeleev Ridge and Alpha Ridge, southern Mendeleev Ridge, Morris Jesup Rise, Lomonosov Ridge and Yermak Plateau, listed in the order of increasing sedimentation rates from ~0.5cm/ka to ~4.8 cm/ka. A detailed study of the relationship between sediment bulk density and grain sizes suggests a strong link between variations in clay abundance and bulk density. Grain size analysis of a Lomonosov Ridge core show that fine silt and clay dominates the interglacials, possibly due to increased suspension freezing of these size fractions into sea ice and/or nepheloid transport. Sediments younger than the marine isotope stage (MIS) 7 generally contain more coarse silt, attributed to a regime shift during the Quaternary with increased iceberg transport into the central Arctic Ocean from MIS 6 and onwards.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: In progress. Paper 4: In progress. Paper 5: In progress. Paper 6: In progress.

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49

Dilley, Thomas Edward 1959. "Late Quaternary loess stratigraphy, soils, and environments of the Shaw Creek Flats Paleoindian sites, Tanana Valley, Alaska". Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282635.

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Abstract (sommario):

The late Quaternary stratigraphy of three Paleoindian archaeological sites, located on the edge of Shaw Creek Flats in the middle Tanana Valley, Alaska, consist of up to 2 meters of calcareous eolian sand, loess, and buried paleosols. Two Paleoindian occupations at the Broken Mammoth, Swan Point, and Mead sites date from 11,800 to 11,000 yr B.P. and from 10,800 to 9500 yr B.P. Well-preserved faunal remains, worked mammoth ivory, stone and organic tools, and at Swan Point, the early occurrence of microblades dating to 11,700 yr B.P., are associated with buried paleosols at the base of the loess. Stratigraphic and radiocarbon-chronological correlations between the sites, and at similar geological sections, suggest the presence of a regionally-correlative, eolian stratigraphy consisting of three main units: (1) a basal gray eolian sand, overlying a deflated, ventifacted, bedrock surface, was deposited as bluff-top sand sheets probably during the Birch Period transition from periglacial steppe-tundra environments to shrub tundra about 12,000 to 14,000 yr B.P. (2) An overlying lower loess unit contains three paleosol complexes, classified as Typic Cryorthents, which consist of a series of cumulative Abk horizons overlying Ck loess parent material. The lower paleosol complex dates to 11,800 to 11,000 yr B.P. as is associated with the initial occupation of the sites. The middle paleosol complex dates from 10,800 to about 9500 yr B.P. and is associated with the second Paleoindian occupation. The upper paleosol complex is weakly developed, contains no cultural material, and reflects an increase in loess deposition rates. Abundant pedogenic carbonate features indicate dry, warm, alkaline soil conditions. Faunal remains, soil characteristics, and regional palynological studies indicate a warm, dry, open parkland of poplar-willow scrub forest during the deposition of the lower loess, paleosol formation, and Paleoindian occupations. (3) An upper loess unit, up to a meter thick, lacks paleosols, has been leached of carbonate, and has a late Holocene Alfic Cryochrept soil developed on its upper surface. Rapid, coarse-grained loess deposition occurred from about 9000 to 6000 yr B.P. By 4500 yr B.P., slow, fine-grained loess deposition began under boreal forest conditions and continues today.

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50

Hodelka, Bailee Nicole. "STRATIGRAPHY AND ORGANIC GEOCHEMISTRY REVEAL PATTERNS OF LATE QUATERNARY PALEO-PRODUCTIVITY AT MONO LAKE, CALIFORNIA". UKnowledge, 2018. https://uknowledge.uky.edu/ees_etds/58.

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Mono Lake (CA) is a hydrologically closed lacustrine basin well-known for its paleo-shorelines, which record fluctuations in water level for the last deglacial and late Holocene. Mono Lake is a sentinel of California’s water supply, situated in the rain shadow of the Sierra Nevada, a mountain range whose snowpack is a vital source of freshwater for urban and agricultural districts to the west and south. Recent droughts, floods, and wildfires show that California is threatened by climate change, but how these changes impact and get recorded by Mono Lake sediments remains poorly known. Here, we use a new radiocarbon-dated deepwater sediment core from Mono Lake to test the hypothesis that organic facies development is controlled by climate and limnological change. An integrated stratigraphic analysis of the core reveals seven lithostratigraphic units that track environmental changes from ~16-4 ka. When compared to available paleo-shoreline and shallow water core data, our results show that high amplitude lakelevel fluctuations of the late Pleistocene produce different patterns of sedimentation and organic enrichment than lower-amplitude water level changes of the early and middle Holocene. The results have implications for understanding patterns of paleo-production and hydroclimate change at Mono Lake.

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