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1.
This paper reviews the paleoenvironmental context for Paleoindian and Early Archaic settlement of the south-central Andes. I attempt to reconcile proposals for late-glacial and early Holocene environmental changes that have originated in several Quaternary sciences. Most useful are the records of changing lake levels, geomorphological indicators of glacial advance and retreat, changes in vegetation as seen through pollen stratigraphy, the record of large mammal extinctions, and the archaeological settlement pattern itself. High lake stands in the central and south-central Andes, c. 12,500 to 11,000 B.P., seem to correspond to glacial retreat. Palynological studies also suggest higher temperatures, coincident with greater summer precipitation from 11,500 B.P. to perhaps 10,000 B.P., followed by some reduction in temperatures and then widespread aridity from about 8500 to 5000 B.P. Environmental change at the Pleistocene/Holocene boundary was at least a major contributing factor to the extinction of horse and sloth around 10,000 B.P. Archaeology of the salt puna and Punta Negra region conforms well with the environmental record, showing human entry by the Early Archaic (11,000-8000 B.P.), subsequent depopulation and perhaps abandonment, then readaptation to more localized resources in the Late Archaic (5500-4000 B.P.).  相似文献   

2.
A phytolith record from Monte Oscuro, a crater lake located 10 m above sea level on the Pacific coastal plain of Panama, shows that during the Late Pleistocene the lake bed was dry and savanna-like vegetation expanded at the expense of tropical deciduous forest, the modern potential vegetation. A significant reduction of precipitation below current levels was almost certainly required to effect the changes observed. Core sediment characteristics indicate that permanent inundation of the Monte Oscuro basin with water occurred at about 10,500 14C yr B.P. Pollen and phytolith records show that deciduous tropical forest expanded into the lake’s watershed during the early Holocene. Significant burning of the vegetation and increases of weedy plants at ca. 7500 to 7000 14C yr B.P. indicate disturbance, which most likely resulted from early human occupation of the seasonal tropical forest near Monte Oscuro and the development of slash-and-burn methods of cultivation.  相似文献   

3.
J.L. Ripley 《Geoarchaeology》1998,13(8):793-818
Archaeological sites that have only surface scatters are usually considered to be of little or no use in reconstructing paleoenvironmental conditions during episodes of human occupation. However, geoarchaeological research at the Skare site in south-central Wisconsin reveals that these sites can be used to provide information about the timing of paleoenvironmental changes and their affect on the location of human occupations. Geomorphic investigations revealed the presence of Alfisols formed in late Wisconsin loess on upland and low bench positions; morphologically younger Mollisols formed in alluvial and colluvial sediments on low alluvial plain positions; and beach sediments that represent the low-water stand of Glacial Lake Yahara. Semiquantitative age control for timing the formation of these soils and the lake level(s) of Glacial Lake Yahara is based on the location of diagnostic artifacts (Early Paleoindian to Late Woodland) recovered during ten separate surface collections. Early and Late Paleoindian artifacts all occur on Alfisols and are only found above the low-water stand of Glacial Lake Yahara, indicating that loess deposition and subsequent soil formation happened sometime between 12,000 and 11,000 yr B.P., and that Glacial Lake Yahara remained near the low-water stand at least until ∼9500 yr B.P. Early Archaic artifacts are present below the low-water stand and provide ages for lowering of the lake to be between 8000 and 9500 yr B.P. Middle Archaic artifacts are present on Mollisols and provide an age of soil formation to be between 5000 and 3000 yr B.P. A majority of Woodland artifacts occur on these Mollisols and are present along the floodplain of the Yahara River, possibly representing a change in subsistence strategy and settlement patterns relative to Paleoindian and Archaic occupations. The agreement of soil morphological and sedimentological data with semiquantitative age data of diagnostic artifacts provides evidence that archaeological surface scatters can be useful tools in dating soils and landforms associated with these sites. © 1998 John Wiley & Sons, Inc.  相似文献   

4.
The Great Plains contain many of the best‐known Paleoindian sites in North America, and a number of these localities were key to determining the chronology of Paleoindian occupations in the years before, during, and since the development of radiocarbon and other chronometric dating methods. Initial attempts at dating were based on correlation with extinct fauna, the “geologic‐climatic” dating method, and stratigraphic relationships of artifacts within sites. By the time radiocarbon dating was developed (1950), the basic Paleoindian sequence (oldest to youngest) was: Clovis‐Folsom‐unfluted lanceolates (such as Plainview, Eden, and Scottsbluff). Initial applications of radiocarbon dating in the 1950s did little to further resolve age relationships. In the 1960s, however, largely through the efforts of C. V. Haynes, a numerical geochronology of Paleoindian occupations on the Great Plains began to emerge On the Southern Great Plains the radiocarbon‐dated artifact chronology is: Clovis (11,600–11,000 yr B.P.); Folsom and Midland (10,900–10,100 yr B.P.); Plainview, Milnesand, and Lubbock (10,200–9800 yr B.P.); Firstview (9400–8200 yr B.P.); St. Mary's Hall, Golondrina, and Texas Angostura (9200–8000 yr B.P.). The chronology for the Northern Great Plains is: Clovis (11,200–10,900 yr B.P.); Goshen (ca. 11,000 yr B.P.); Folsom (10,900–10,200 yr B.P.); Agate Basin (10,500–10,000 yr B.P.); Hell Gap (10,500–9500 yr B.P.); Alberta, Alberta‐Cody (10,200–9400 yr B.P.); Cody (Eden‐Scottsbluff) (9400–8800 yr B.P.); Angostura, Jimmy Allen, Frederick, and other parallel‐oblique types (9400–7800 yr B.P.). Fifty years after the development of radiocarbon dating, the basic typological sequence has not changed significantly except for the realization that there probably was significant temporal overlap of some point types, and that the old unilinear sequence does not account for all the known typological variation. The chronology has been continually refined with the determination of hundreds of radiocarbon ages in recent decades. © 2000 John Wiley & Sons, Inc.  相似文献   

5.
Geoarchaeological investigations at the Clovis type site, Blackwater Locality No. 1, in 1983 and 1984 included core drilling, archaeological test excavations, stratigraphic profiling, sedimentary analyses, and radiocarbon dating. Six lines of core holes transverse to the outlet channel clearly defined the subsurface configuration and stratigraphy of the prehistoric spring run. Pieces of large animal bone from units B, C, D, and E that elsewhere in the site contain Paleoindian artifacts suggest occurrences of additional buried sites along the ancient spring run. Four Paleoindian projectile points recovered during archaeological testing confirm these prospects. The Clovis type site, located in an abandoned gravel pit, is in a natural depression initially occupied by a late Pleistocene lake. After breaching of the depression by overflow or sapping, it became a springhead and was enlarged by slumping and slopewash. Detailed stratigraphic profiling of the south wall of the abandoned gravel pit provided precise stratigraphic control for sediment sampling and radiocarbon dating, and revealed more complex microstratigraphy and facies relationships than heretofore known for the site. The interfingering of dune facies around the depression with lacustrine and spring-laid facies within it aid paleoclimatic interpretation. Deflational contacts within the depression appear to correlate with adjacent wedges of dune sand reflecting relatively arid intervals. Between these arid episodes occur intervals of increased ground water level attended initially by deposition of spring-laid sands of unit B during the late Pleistocene (13,000–11,500 yr B.P.). As the water table rose following a period of severe deflation, slumping and gravity flow deposited clayey sand, Unit C, on the floor of the blowout between 11,500 and 11,000 yr B.P. During this time Clovis people first appeared at the site. After another brief period of deflation, a lake rose causing sand of Unit D0 to be washed in from shore followed by deposition of diatomities, units D1 and D2. These were separated by a brief influx of eolian sand, unit D2z. Between 10,800 and 10,000 yr B.P. outflow from the lake was reduced by accumulation of eolian sand in the outlet while Folsom people and later Agate Basin people arrived to hunt bison during this time. Cody complex people appeared during and after a brief erosional episode that preceded deposition of eolian silt and sand of units E and F from 10,000 to 8000 yr B.P. Eolian deposition during post-Folsom time converted the pond to a wet meadow and eventually, during Cody time, to a grassy swale. Some of these deposits were blown out during the Altithermal arid period (ca. 8000-5000 yr B.P.), a time when prehistoric Archaic peoples excavated wells in the floor of the depression. Subsequent eolian activity has resulted in deflation and dune migration during the late Holocene. The best prospects for Paleoindian finds are along the buried outlet south of the south wall and in early Holocene dune sands on the uplands around the depression. © 1995 John Wiley & Sons, Inc.  相似文献   

6.
Soil-sediment records and radiometric dating allow the development of environmental histories of three South Platte River alluvial terraces in the vicinity of Kersey, Colorado. These advocate a correlation with Holocene glacial records for the Colorado Front Range (Benedict, 1981, 1985). The archaeological potential of the Kersey fill, the Kuner strath, and the Hardin fill depends upon their age and sediment context. The oldest and most extensive terrace is the Kersey fill. The position of cultural components on the Kersey terrace implies an association of older Paleoindian sites (11,500–10,000 B.P.) with channel banks and bars on the terrace, younger Paleoindian sites (<10,000 B.P.) with terrace margins near the river, and Archaic and younger sites with eolian deposits on the terrace. An association of Clovis components with both Kersey alluvium and adjacent eolian dune fields indicates that eolian deposition began prior to 11,000 B.P. and that sediment availability influenced early Holocene eolian deposition. Examination of 150 cores and 75 backhoe test units along an 8-km study corridor demonstrates that Paleoindian sites are not as abundant on the Kersey terrace as previous researchers have proposed. Although the incision of the Kuner strath began earlier than 9600 B.P., we propose that its greatest potential is to yield cultural components that postdate ca. 7250 B.P. In turn, the Hardin fill may yield cultural components dating to the Kuner abandonment (ca. 6380 B.P.). However, Hardin sediment and soil records recommend that this fill terrace's highest potential is to yield in situ cultural components dating from ca. 1900 to 120 B.P. © 1994 John Wiley & Sons, Inc.  相似文献   

7.
Pollen records from two sites in western Oregon provide information on late-glacial variations in vegetation and climate and on the extent and character of Younger Dryas cooling in the Pacific Northwest. A subalpine forest was present at Little Lake, central Coast Range, between 15,700 and 14,850 cal yr B.P. A warm period between 14,850 and 14,500 cal yr B.P. is suggested by an increase inPseudotsugapollen and charcoal. The recurrence of subalpine forest at 14,500 cal yr B.P. implies a return to cool conditions. Another warming trend is evidenced by the reestablishment ofPseudotsugaforest at 14,250 cal yr B.P. Increased haploxylonPinuspollen between 12,400 and 11,000 cal yr B.P. indicates cooler winters than before. After 11,000 cal yr B.P. warm dry conditions are implied by the expansion ofPseudotsuga.A subalpine parkland occupied Gordon Lake, western Cascade Range, until 14,500 cal yr B.P., when it was replaced during a warming trend by a montane forest. A rise inPinuspollen from 12,800 to 11,000 cal yr B.P. suggests increased summer aridity.Pseudotsugadominated the vegetation after 11,000 cal yr B.P. Other records from the Pacific Northwest show an expansion ofPinusfrom ca. 13,000 to 11,000 cal yr B.P. This expansion may be a response either to submillennial climate changes of Younger Dryas age or to millennial-scale climatic variations.  相似文献   

8.
This article presents a combined pollen and phytolith record of a 1.70-m sediment core from the wetlands of India Muerta (33° 42′ S, 53° 57′ W) in the lowland Pampa (grasslands) of southeastern Uruguay. Six 14C dates and the pollen and phytolith content of the samples permitted the recognition of four distinct climatic periods between 14,850 14C yr B.P. and the present. The Late Pleistocene period (between ca. 14,810 and ca. 10,000 14C yr B.P.) was characterized by drier and cooler conditions indicated by the presence of a C3-dominated grassland. These conditions prevailed until the onset of the warmer and more humid climate of the Holocene around 9450 14C yr B.P. The early Holocene (between around 10,000 and 6620 14C yr B.P.) was characterized by the establishment of wetlands in the region as evidenced by the formation of black peat, the increase in wetland taxa, and the replacement of C3 Pooideae by C4 Panicoideae grasses. During the mid-Holocene, around 6620 14C yr B.P., began a period of environmental change characterized by drier climatic conditions, which resulted in the expansion of halophytic communities in the flat, low-lying areas of the wetlands of India Muerta. About 4020 14C yr B.P. a massive spike of Amaranthaceae/Chenopodiaceae coupled with a radical drop in wetland species indicates another major and more severe period of dryness. After ca. 4000 14C yr B.P., a decrease of halophytic species indicates the onset of more humid and stable climatic conditions, which characterized the late Holocene.The findings reported in this article substantially improve our knowledge of the late Glacial and Holocene climate and vegetation in the region. The data provide a detailed record of the timing and severity of mid-Holocene environmental changes in southeastern South America. Significantly, the mid-Holocene drying trend coincided with major organizational changes in settlement, subsistence, and technology of the pre-Hispanic populations in the region, which gave rise to early Formative societies. This study also represents the first combined pollen and phytolith record for southeastern South America reinforcing the utility of phytoliths as significant indicators of long-term grassland dynamics.  相似文献   

9.
A 17.5 m sedimentary core from Lake La Yeguada, central Panama provides the first complete Holocene sequence for the Pacific watershed of Lower Central America. Phytolith, pollen, and charcoal records document a long lowland history of foraging and food production. Human modification of tropical forests can be described as systematic during the early Holocene and was possibly associated with small-scale (garden?) horticulture involving native tubers. The incorporation of seed crops like maize and development of slash and burn techiques for larger-scale field systems is indicated by the increase of secondary forest taxa and removal of primary trees between 7000 and 4000 years ago. After this time, agricultural intensification in an essentially deforested landscape proceeded to the point where, by the time of Christ, agricultural abandonment of the lake watershed may have occurred as a result of loss of soil fertility. Events such as this in the interfluve forests may have, in part, precipitated the coalescence of population and settlement around the river valleys and the emergence of sedentary village life.  相似文献   

10.
《Quaternary Science Reviews》2004,23(18-19):1955-1987
North American archaeologists have spent much effort debating whether Early Paleoindian foragers were specialized hunters of megafauna or whether they pursued more generalized subsistence strategies. In doing so, many have treated the foraging practices of early North Americans as if they must have been uniform across the continent, even though others have pointed out that adaptations appear to have varied among groups inhabiting different kinds of environments. Resolving these issues fully requires referring to archaeofaunal data and evaluating those data critically. In this paper, we conduct such an evaluation of the existing Early Paleoindian faunal record, which we then use to test the hypothesis that early Americans across the continent specialized in the hunting of megafauna. After detailed attention is given to taphonomic issues, to the limited geographical distribution of sites with secure associations between humans and prey taxa, and to differences among sites in the roles that they likely played in settlement and subsistence systems, it becomes clear that the faunal record provides little support for the idea that all, or even any, Early Paleoindian foragers were megafaunal specialists. It does appear, however, that there was considerable variability in Early Paleoindian prey choice across the continent, which was likely related to variability in the environments that different groups inhabited.  相似文献   

11.
Investigations were conducted along the middle South Platte River to better define the geomorphic contexts of Paleoindian sites and to reconstruct the alluvial and eolian geochronology. Paleoindian sites are associated with the Kersey terrace (the downstream equivalent of the Broadway terrace). The Kersey alluvium was deposited during Clovis occupation and the surface stabilized by 10,000 B.P. Post-Clovis sites post-date aggradation and stream downcutting may have started as early as 10,500 B.P. Subsequent floodplain development and downcutting formed the Kuner terrace (the possible downstream equivalent of the Piney Creek terrace) no later than 3000 B.P. and the Hardin terrace probably within the last 1000 years. Soils on the Kersey terrace are Ustochrepts (gravelly alluvium) or Haplustalfs (sandy and clayey alluvium). Soils on the Kuner terrace are cumulic Ustorthents and Ustochrepts. Soils on the Hardin terrace are Ustorthents with no obvious horizonation. Eolian sands began accumulating in the region by 10,000 B.P., but most are probably late Holocene deposits and are indicative of drier post-Pleistocene climate. Correlations with deposits in low order tributaries and other drainages can be difficult to make a) using soils because soil development varies as a function of parent material texture and b) because aggradation and degradation may be out-of-phase.  相似文献   

12.
Dodson, John R. & Bradshaw, Richard H. W. 1987 06 01: A history of vegetation and fire, 6,600 B.P. to present, County Sligo, western Ireland. Boreas , Vol. 16, pp. 113–123. Oslo. ISSN 0300–9483.
Two lake sites on metamorphic rocks with small catchments and one mor humus deposit have been analysed to assess the relative influences of fire, man and climate upon the regional and local vegetation of the Lough Gill region of County Sligo. The vegetation of the area was dominated by mixed woodland from 6,600 B.P. to 600 B.P. The first evidence of human impact on the forests was around 5,400 B.P. in the form of clearance for pasture. The intensity of human impact varied between sites, and there were periods of forest recovery as well as decline. From 600 B.P. widespread forest destruction took place, and pasture with heathland became predominant. Pinus sylvestris had a major presence until about 5,400 B.P. It declined from this time and had a patchy distribution by 2,000 B.P. The decline of Pinus was linked with the expansion of treeless peatland in what are presumed to be wet periods, and Pinus recovery in drier periods. Fire may have encouraged the spread of heathland at the expense of Pinus . Arbutus unedo pollen was found at Slish Lake as early as 1,900 B.P., suggesting that it is native to this area. Isolated trees survive today at woodland edges. Charcoal particles occurred in all the profiles. Fire was particularly associated with heathland communities, and may have been used as a management tool to improve grazing conditions. Some of the phases of woodland decline correlate strongly with charcoal input suggesting forest destruction by fire.  相似文献   

13.
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14.
Interbedded, organic-rich terrestrial and marine sediments exposed along the eastern coastal lowland of Vancouver Island contain an almost continuous record of middle Wisconsin vegetation and climate. The record has been interpreted largely from palynostratigraphic studies at three sites and supported by a study of modern pollen spectra from the three major biogeoclimatic zones of the extant vegetation. Radiocarbon dates from a variety of organic materials in the middle Wisconsin beds reveal that the fossil pollen spectra span an interval ranging from approximately 21,000 yr B.P. to more than 51,000 yr B.P. The spectra are divided into eight major pollen zones encompassing the Olympia Interglaciation and early Fraser Glaciation geologicclimate units of the Pacific Northwest. The Olympia Interglaciation extended from before 51,000 yr B.P. to ca. 29,000 yr B.P. and was characterized by a climate similar to present. During the early Fraser Glaciation, from 29,000 years ago to approximately 21,000 yr B.P., climate deteriorated until tundra like conditions prevailed. These pollen sequences are correlative with those of coastal British Columbia and partly with those from Olympic Peninsula, but apparently are not comparable with events in the Puget Lowland.  相似文献   

15.
This paper documents the results of nondestructive X‐ray fluorescence (XRF) geochemical analyses and comparisons of silicified rhyolites from the Black Canyon and Sedillo Hill prehistoric quarries near Socorro, New Mexico, and subsequent comparisons of the quarry rhyolites with 11 temporally diagnostic projectile points. At the current level of analysis, findings indicate that (1) the two quarries are chemically distinct and (2) the lithic materials of two projectile points match the silicified rhyolite from the Black Canyon quarry, suggesting quarry use during the Early Archaic period (4800–3200 B.C.) and the Late Archaic period (1800–800 B.C.). A close match between the Black Canyon rhyolite and one other point provides tentative support for use of the quarry during the Clovis Paleoindian period (9500–9000 B.C.). Additional geochemical analyses of the two quarries and other regional sources should be undertaken to verify these results and further expand our understanding of prehistoric mobility in the Southwest. © 2004 Wiley Periodicals, Inc.  相似文献   

16.
The Santa Cruz arroyo in the Tucson Basin, Arizona, has undergone major environmental changes over the last 8000 years. the Holocene stratigraphy along a 15 km segment of the arroyo, known as the San Xavier reach, which traverses the San Xavier Indian Reservation was investigated in detail. the Holocene alluvial sequence reveals that aggradation occurred until 8000 yr B.P. within a braided stream, was followed by a major period of channel erosion and widening from 8000 to 5500 yr B.P., which, in turn, was followed by vertical aggradation of the floodplain and five short periods of channel cutting. Broad climatic changes are correlated with major changes in the fluvial regime and landscape. However, the cycles of arroyo cutting and filling, during the semiarid climate of the last 2500 years, were probably the result of the creation of unstable internal geomorphic conditions, flooding, and human impacts on the floodplain. the alluvial history of the San Xavier reach has had a pronounced effect on the preservation and completeness of the archaeological record. Periods of erosion have created absences or gaps in the archaeological record and deep burial has removed some of the preserved archaeological remains from view. Environmental changes on the floodplain also influenced late prehistoric Hohokam settlement and subsistence patterns in the San Xavier region.  相似文献   

17.
A buried archaeological site at Tecolote Canyon provides an ideal case study for relating past human land use patterns to changes in coastal paleogeography. Postglacial sea level transgression, erosion, and other marine and fluvial processes form the context for examining two deeply buried archaeological components excavated at CA‐SBA‐72. Archaeological shellfish assemblages provide proxy data for evaluating the evolution of local marine environments. Pismo clams dominate shellfish assemblages dated to 5800 cal yr B.P., suggesting the presence of a broad and sandy, high‐energy beach environment. At 5500 cal yr B.P., the almost exclusive use of California mussels by humans signals the development of rocky intertidal habitats. During the late Holocene, estuarine species dominate the marine mollusk assemblages at CA‐SBA‐72, reflecting the development of local estuarine conditions or trade with nearby Goleta Slough villages. The buried components at Tecolote Canyon appear to have served as temporary camps for shellfish harvesting and processing. While general changes in coastal paleogeography and human subsistence have been reconstructed for the Santa Barbara Coast, high resolution ecological data from Tecolote Canyon suggest that Native peoples also adapted to localized and shorter‐term shifts in intertidal habitats, changes not evident in most larger or more disturbed surface sites in the region. Linking these changes with shifts in human land use patterns highlights the interaction between humans and a dynamic coastal system. These data demonstrate the importance of small, buried sites in understanding the full spectrum of human subsistence and settlement choices and local environmental change. © 2004 Wiley Periodicals, Inc.  相似文献   

18.
While single pollen records are widely used in reconstructing the environment for nearby prehistoric settlements, they are less helpful when addressing large‐scale issues of variation in human settlement patterns. In order to assess the impact of vegetation change on regional prehistoric settlement and subsistence patterns in an ecotone sensitive area, we inferred the general change in main vegetation types based on palaeobotanical investigations from across northernmost Fennoscandia. Tundra vegetation was predominant during the Lateglacial and earliest parts of the Holocene. Maritime birch forests rich in ferns started to expand c. 11 000 cal. a BP and became dominant from 10 000 cal. a BP. Pine expanded from the NE of the investigation area and pine‐birch forest dominated in the inland around 8000 cal. a BP. A gradual degeneration of forest towards more open birch woodland started c. 6000 cal. a BP with the most marked change around 3500 cal. a BP. Along the northern outer coast, this eventually led to open heathland. Comparison with the archaeological setting suggests a general correlation between low forest cover and extensive mobility patterns, while widespread and varied forest cover appear to have led to a more sedentary way of life. The background for this is arguably that the forested landscapes hosted a larger diversity of resources within a shorter foraging distance, while areas and periods with low forest cover required longer travels to obtain the desired prey and materials.  相似文献   

19.
Four pollen sequences along a transect from north-central Iowa to southeast Wisconsin reveal the distribution of prairie and forest during the Holocene and test the use of pollen isopolls in locating the Holocene prairie-forest border. Prairie was dominant in central Iowa and climate was drier than present from about 8000 to 3000 yr B.P. During the driest part of this period in central Iowa (6500-5500 yr B.P.), mesic forest prevailed in eastern Iowa and Wisconsin, suggesting conditions wetter than at present. Prairie replaced the mesic forest about 5400 yr B.P. in eastern Iowa but did not extend much farther east; mesic forests were replaced in southern Wisconsin and northern Illinois about 5400 yr B.P. by xeric oak forests. This change from mesic to xeric conditions at 5400 yr B.P. was widespread and suggests that the intrusion of drier Pacific air was blocked by maritime tropical air from the Gulf of Mexico until the late Holocene in this area.  相似文献   

20.
Sedimentological, faunal, and archaeological investigations at the Sunshine Locality, Long Valley, Nevada reveal a history of human adaptation and environmental change at the last glacial–interglacial transition in North America's north-central Great Basin. The locality contains a suite of lacustrine, alluvial, and eolian deposits associated with fluvially reworked faunal remains and Paleoindian artifacts. Radiocarbon-dated stratigraphy indicates a history of receding pluvial lake levels followed by alluvial downcutting and subsequent valley filling with marsh-like conditions at the end of the Pleistocene. A period of alluvial deposition and shallow water tables (9,800 to 11,000 14C yr B.P.) correlates to the Younger Dryas. Subsequent drier conditions and reduced surface runoff mark the early Holocene; sand dunes replace wetlands by 8,000 14C yr B.P. The stratigraphy at Sunshine is similar to sites located 400 km south and supports regional climatic synchroneity in the central and southern Great Basin during the terminal Pleistocene/early Holocene. Given regional climate change and recurrent geomorphic settings comparable to Sunshine, we believe that there is a high potential for buried Paleoindian features in primary association with extinct fauna elsewhere in the region yet to be discovered due to limited stratigraphic exposure and consequent low visibility.  相似文献   

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