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Late holocene coseismic subsidence and coincident tsunamis, southern Cascadia subduction zone, Hookton Slough, WIGI (Humboldt Bay), California /Patton, Jason Robert. January 2004 (has links) (PDF)
Thesis (M.S.)--Humboldt State University, 2004. / Includes bibliographical references (leaves 59-65). Also available via the Internet.
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North Pacific Late Holocene Climate Variability and Atmospheric CompositionOsterberg, Erich Christian January 2007 (has links) (PDF)
No description available.
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Μορφοδυναμική εξέλιξη της πεδιάδας των Καλαβρύτων στο Ολόκαινο / Human settlement in an evolving landscape during the Holocene: a case of river bed evolution in Kalavryta plainΜισύρη, Ζωή 26 March 2013 (has links)
Λεπτομερείς τοπογραφικές έρευνες για τη στρωματογραφία του Ολόκαινου σε συνεργασία με τη μελέτη ενός σπουδαίου αριθμού από αρχαιολογικές ανακαλύψεις, οι οποίες παρέχουν πολύτιμες πληροφορίες για μία καλύτερη κατανόηση της σχέσης ανάμεσα στους ανθρώπους και της περιβαλλοντικής εξέλιξης. Κατά τη διάρκεια του πρώιμου Ολόκαινου, οι ανθρώπινες δραστηριότητες ήταν επηρεασμένες σε μεγάλο βαθμό από περιβαλλοντικές κλιματικές αλλαγές, όπως αποδείχτηκε από τα εύρηματα θαμμένων αρχαιολογικών τοποθεσιών στις ποτάμιες αποθέσεις της κοιλάδας του ποταμού Βουραϊκού. / Detailed field investigations of Holocene stratigraphy in combination with the study of an important number of archaeological discoveries provided valuable information for a better understanding of the relationship between man and the environmental evolution. During Early Holocene, human activities were strongly influenced by climate-induced environmental changes, as proven by the occurrence of archaeological sites buried within the alluvial depos-its of the Vouraikos river valley.
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Diatom analysis of the Late Quaternary sediments from the area of the Czech RepublicBEŠTA, Tomáš January 2014 (has links)
Diatom analysis performed on sediment profiles from several localities provided information on past changes in the aquatic environment related to climatic and artificial shifts since the Last Glacial-Interglacial Transition. The practicality of diatom analysis from fish guts of three European fish species in palaeolimnological studies was tested.
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Mesolithic to Romano-British archaeology and environmental change of the Severn Estuary, EnglandDruce, Denise January 2000 (has links)
No description available.
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The Archaeology of Local Human Response to an Environmental TransformationJanuary 2013 (has links)
abstract: This research addresses human adaptive decisions made at the Pleistocene-Holocene transition - the transition from the Last Glacial Maximum (LGM) to the climate regime in which humankind now lives - in the Mediterranean region of southeast Spain. Although on a geological time scale the Pleistocene-Holocene transition is the latest in a series of widespread environmental transformations due to glacial-interglacial cycles, it is the only one for which we have a record of the response by modern humans. Mediterranean Spain lay outside the refugium areas of late Pleistocene Europe, in which advancing ice sheets limited the land available for subsistence and caused relative demographic packing of hunter-gatherers. Therefore, the archaeological records of Mediterranean Spain contain more generally applicable states of the Pleistocene-Holocene transition, making it a natural laboratory for research on human adaptation to an environmental transformation. Foragers in Mediterranean Spain appear to have primarily adapted to macroclimatic change by extending their social networks to access new subsistence resources and by changing the mix of traditional relationships. Comparing faunal records from two cave sites near the Mediterranean coast with Geographic Information System (GIS) reconstructions of the coastal littoral plain from the LGM to the Holocene indicates the loss of the large ungulate species (mainly Bos primigenius and Equus) at one site coincided with the associated littoral disappearing due to sea level rise in the late Upper Paleolithic. Farther north, where portions of the associated littoral remained due to a larger initial mass and a more favorable topography, the species represented in the faunal record were constant through time. Social boundary defense definitions of territory require arranging social relationships in order to access even this lightly populated new hunting area on the interior plain. That the values of the least-cost-paths fit the parameters of two models equating varying degrees of social alliance with direct travel distances also helps support the hypothesis that foragers in Mediterranean Spain adapted to the consequences of macroclimatic change by extending their social networks to gain access to new subsistence resources Keeping these relationships stable and reliable was a mitigating factor in the mobility patterns of foragers during this period from direct travel to more distant down-the-line exchange. Information about changing conditions and new circumstances flowed along these same networks of social relationships. The consequences of climate-induced environmental changes are already a concern in the world, and human decisions in regard to future conditions are built upon past precedents. As the response to environmental risk centers on increasing the resilience of vulnerable smallholders, archaeology has an opportunity to apply its long-term perspective in the search for answers / Dissertation/Thesis / Ph.D. Anthropology 2013
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Late Quaternary vegetation, climate, fire history, and GIS mapping of Holocene climates on southern Vancouver Island, British Columbia, CanadaBrown, Kendrick Jonathan 05 February 2018 (has links)
Pollen and microscopic charcoal fragments from seven sites (East Sooke Fen and
Pixie, Whyac, Porphyry, Walker, Enos, and Boomerang lakes) were used to reconstruct
the post-glacial vegetation, climate, and fire disturbance history on southern Vancouver
Island, British Columbia, Canada. A non-arboreal pollen and spore zone occurs in the
basal clays at Porphyry Lake and likely represents a tundra or tundra-steppe ecosystem.
This zone precedes the Pimis contorta (lodgepole pine) biogeochron that is generally
considered to have colonised deglaciated landscapes and may represent a late
Wisconsinan glacial refugium. An open Pinus contorta woodland characterised the
landscape in the late-glacial interval. Fires were rare or absent and a cool and dry climate
influenced by “continental-scale katabatic” easterly winds dominated. Closed lowland
forests consisting of Picea (spruce), Abies (fir), Tsuga heterophylla (western hemlock),
and Tsuga mertensiana (mountain hemlock) with P. contorta and Alnus (alder) and subalpine
forests containing Picea, Abies, and T. mertensiana with P. contorta replaced the
P. contorta biogeochron in the late Pleistocene. Fires became more common during this
interval even though climate seems to have been cool and moist. Open Pseudotsuga
menziesii (Douglas-fir) forests with Pteridium (bracken fern) in the understory and Alnus in moist and disturbed sites expanded westward during the warm dry early Holocene. At this time closed Picea, T. heterophylla, and possibly Alnus forests grew in the wettest part of southern Vancouver Island at Whyac Lake. At high elevations, forests consisting of T.
heterophylla and Pseudotsuga coupled with Alnus expanded during the early Holocene. Fires occurred frequently in lowland forested ecosystems during this interval, although East Sooke Fen in a dry, open region experienced less fire. At high elevations, charcoal increased somewhat from the late Pleistocene, indicating slightly more fires and reflecting
continued moist conditions at high elevations. The mid and late Holocene was
characterized by increasing precipitation and decreasing temperature respectively. Mid
Holocene lowland forests were dominated by Pseudotsuga with T. heterophylla and
Alnus in southeastern regions, T. heterophylla and Thuja plicata (western red-cedar) in
southern regions, and T. heterophylla and Picea in southwestern regions. An overall
decrease in charcoal influx suggests a decrease in lowland fires, although locally isolated
fire events are evident in most sites. Quercus garryana (Garry oak) stands spread
westward during the mid Holocene, attaining maximum extent between East Sooke Fen
and Pixie Lake, approximately 50 km beyond their modem limit. Lowland sites record a
general decrease in fires at this time. At high elevation, mid Holocene forests were
dominated by T. heterophylla, Picea, and Abies with Alnus. An overall increase in
charcoal influx at high elevations may reflect an increase in the number of charcoal
fragments entering the basins by overland flow as opposed to an increase in fire incidence because climate was moister. In the late Holocene, closed T. heterophylla and T. plicata forests became established in wetter western regions, Pseudotsuga forests occupied drier eastern portions, and T. mertensiana and Cupressaceae, likely Chamaecyparis
nootkatensis (Alaska yellow cedar), forests were established in sub-alpine sites. Lowland
fires were infrequent in wet western regions but frequent in drier eastern regions. A slight
reduction in charcoal influx generally occurs at high elevations, implying fewer fires. A recent increase in charcoal influx at East Sooke Fen and Whyac, Walker, Enos, and Boomerang lakes may reflect anthropogenic burning. Holocene paleoclimates were
reconstructed at 1,000 year intervals through a geographic information system (GIS)
using contemporary climate data and surface and fossil pollen assemblages by
establishing empirical regression equations that calibrated contemporary precipitation and
temperatures to present day Douglas-fir-western hemlock (DWHI) and T. heterophylla-T. mertensiana (THMl) pollen ratios. / Graduate
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Modern and late Holocene climate-tree-ring growth relationships and growth patterns in Douglas-fir, coastal British Columbia, CanadaZhang, Qibin 04 May 2018 (has links)
This thesis investigates nonlinear climate-growth relationships and spatio-temporal variations in radial growth of Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) in coastal British Columbia (BC), Canada. The technique of Artificial Neural Network (ANN) is used to model tree-ring growth response to climatic variables. Spatial variations in radial growth are examined by comparing ring-width chronologies from three sites on southeastern Vancouver Island and nine sites in Bella Coola area of central coast BC. Radial growth in late Holocene is analyzed by examining ring-width chronologies developed from subfossil Douglas-fir at the Heal Lake site on southern Vancouver Island.
A two-level linear aggregate model is proposed as an improved conceptual framework for study of tree-rings and environment. This model is useful for better understanding the interactions and transformations between different environmental factors and for unambiguous interpretation of the impact of disturbance on tree growth. The ANN technique is demonstrated to be superior to the traditional linear regression approach because of its ability to capture nonlinear and complex relationships between climatic variables and tree-ring growth. The ANN model can be used to predict tree-ring growth under given climatic conditions, and to understand climate-growth relationships by scenario analysis. Comparisons of tree-ring chronologies from three sites on southeastern Vancouver Island suggest that the climate-growth responses are generally similar. In the Bella Coola area of central coast BC, principal component analysis shows that there is common growth response throughout the nine sites of different elevations. However, there is also contrasting growth responses between sites of high and low elevations. The growing season precipitation is likely a major factor controlling radial growth of Douglas-fir on macro-regional scale in coastal BC. Five floating ring-width chronologies in the past 3rd and 4th millennia are developed using 79 subfossil Douglas-fir from the Heal Lake site on southern Vancouver Island. These chronologies show slight fluctuations and strong variations at different intervals. Notable growth anomalies occurred at about 4000 years before present, suggesting intense environmental changes, e.g., frost and droughts, at a time of suspected climate transition. The results of this study will be of use to forest management and climate studies in coastal BC. / Graduate
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Late-Holocene Faunal and Landscape Change in the BahamasSteadman, David W., Albury, Nancy A., Maillis, Perry, Mead, Jim I., Slapcinsky, John, Krysko, Kenneth L., Singleton, Hayley M., Franklin, Janet 01 February 2014 (has links)
We report an intertidal, bone-rich peat deposit on the windward (Atlantic Ocean) coast of Abaco, The Bahamas. The age of the Gilpin Point peat (c. 950-900 cal. yr BP) is based on five overlapping radiocarbon dates (one each from single pieces of wood of buttonwood Conocarpus erectus and sabal palm Sabal palmetto, and single bones of the Cuban crocodile Crocodylus rhombifer, Albury's tortoise Chelonoidis alburyorum, and green turtle Chelonia mydas). The short time interval represented by the charcoal-rich peat suggests rapid sedimentation following initial anthropogenic fires on Abaco. The site's diverse snail assemblage is dominated by terrestrial and freshwater species. The peat is exposed today only during exceptionally low tides, suggesting a lower sea level at the time of deposition as well as a degrading shoreline during the past millennium. Fossils from Gilpin Point represent a late-Holocene vertebrate community at the time of first human presence; only 10 of the 17 identified species of amphibians, reptiles, birds, and mammals still live on Abaco. Numerous unhealed bite marks on the inside of the thick carapaces of the green turtle attest to consumption by Cuban crocodiles, which probably scavenged turtles butchered by humans. This concept, along with the dense concentration of bones in the peat, and charring on some bones of the green turtle and Abaco tortoise, suggests a cultural origin of the bone deposit at Gilpin Point, where the only Amerindian artifact recovered thus far is a shell bead.
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Geologic Mapping, Alluvial Stratigraphy, and Optically Stimulated Luminescence Dating of the Kanab Creek Area, Southern UtahSumma, Michelle Carlene 01 December 2009 (has links)
At the turn of the century, Kanab Creek incised 30-meters into its alluvium, leaving behind fluvial terraces and thick basin fill sediments exposed along arroyo walls. Research objectives were to determine the timing and causes of past valley-filling and arroyo-cutting episodes along a 20 km-long reach of Kanab Creek in southern Utah. Fluvial deposits were mapped at the 1:12,000 scale and sediments were described and dated using Optically Stimulated Luminescence (OSL) and radiocarbon dating. The Kanab Creek valley can be divided into a narrow, upper terraced reach and a broad lower basin fill reach near Kanab, Utah. The most prominent terrace in the upper reach is Quaternary alluvial terrace 4 (Qat4), followed by Qat3, Qat2/3, and Qat2 map units. These are composed of tabular-bedded, fine-grained sand, silt, and clay layers. The Qat2/3 map unit is a both a fill and fill-cut terrace underlain by Qa4, Qa3, and Qa2 alluvium and is used when the Qat3 fill-cut (fill-strath) terrace can not be differentiated from the Qat2 fill terrace due to their similar geomorphic position. The Qat3 fill-cut terrace upstream correlates to ~8 meters of aggradation downstream. The youngest terrace, Qat1, is a minor terrace, composed of coarse-grained channel facies. More recent channel and floodplain deposits were deposited over the last century following arroyo cutting. OSL and radiocarbon results suggest at least four cycles of fluvial cutting and filling: >6-3.5ka (Qa4), ~3->1ka (Qa3), 0.7-0.12ka (Qa2), and post-1880 AD (Qa1). Correlation to regional climate records suggests major periods of aggradation correlate to regionally cooler and wetter climatic intervals. Periods of arroyo cutting occurred at >6ka, ~3ka, 1-0.7ka, and during historic arroyo cutting (1882-1914 AD), and correlate to regionally warmer, drier intervals. These periods of aggradation and incision are roughly contemporaneous with regional drainages, except for the large aggradation seen in Kanab Creek 6-3.5ka (Qa4). Analysis of terrace longitudinal profiles indicates Qat4 has the lowest concavity suggesting that Qat4 aggraded during a period of greater sediment supply and/or reduced flood regime. Although OSL samples exhibited some degree of incomplete zeroing, calculated ages using a minimum age model are consistent with radiocarbon results.
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