Quaternary stratigraphy and geoarchaeology of the colorado and concho rivers,west texas

Geoarchaeological investigations in an area surrounding the confluence of the upper Colorado and Concho Rivers, Edwards Plateau of West Texas, have produced a detailed landscape evolution model which provides a framework for discussion of the influences of geomorphic processes on the development, preservation, and visibility of the archaeological record. Field mapping within the study area has differentiated six allostrati-graphic units of fluvial origin in both valleys, as well as extensive eolian sand sheets along the Colorado River. Early to middle Pleistocene terrace remnants cap many upland areas, whereas two distinct late Pleistocene terrace surfaces are widespread within the study area at somewhat lower elevations. Fluvial activity during the time period of human occupation is represented by an extensive Holocene terrace and underlying valley fill, which is up to 11 m in thickness. Valley fill sediments can be subdivided into allostratigraphic units of early to middle Holocene (ca. 10,000–5000 yr B.P.) and late Holocene age (ca. 4600–1000 yr B.P.), which are separated by a buried soil profile. The modern incised channels and very narrow floodplains represent the last millennium. Eolian sand sheets of early to middle Holocene age overlie limestone- and shale-dominated uplands, Pleistocene terraces, and in some cases the Holocene valley fill along the Colorado River. Pleistocene terraces have been stable features in the landscape and available for settlement through the time period of human occupation. Archaeological materials of all ages occur at the surface, and the record preserved in individual sites range from that associated with discrete periods of activity to longer-term palimpsests that represent repeated use over millennia. Sites within early to middle Holocene and late Holocene fills represent short-term utilization of constructional floodplains during the Paleoindian through early Archaic and middle to late Archaic time periods respectively. By contrast, those that occur along the buried soil profile developed in the early to middle Holocene fill record middle to late Archaic cultural activity on stable terrace surfaces, and represent relatively discrete periods of activity to longer-term palimpsests that represent repeated use over the 3000–4000 years of subaerial exposure. Late Prehistoric sites occur as palimpsests on soils developed in late Holocene alluvium or stratified within modern floodplain facies. Paleoindian through Late Prehistoric sites occur stratified within eolian sand sheets or along the unconformity with subjacent fluvial deposits. The landscape evolution model from the upper Colorado and Concho Rivers is similar to that developed for other major valley axes of the Edwards Plateau. This model may be regionally applicable, and can be used to interpret the geomorphic setting and natural formation processes for already known sites, as well as provide an organizational framework for systematic surface and subsurface survey for new archaeological records. 0 1992 John Wiley & Sons, Inc.     

Chronostratigraphy of upper James river floodplain sediments: Implications for southeastern North Dakota archaeology

Test excavations have been conducted at several dozen prehistoric archaeological sites on the James River floodplain in southeastern North Dakota. Radiocarbon dates and other evidence from these tested artifact deposits indicate that floodplain sedimentary contexts above today's river level are entirely Late Holocene in age. Middle and Early Holocene sediments are more deeply buried. Cultural strata from Late Plains Archaic, Early Plains Woodland, Middle Plains Woodland, and Plains Village settlements are characteristically contained within paleosols in the Late Holocene floodplain sediments. There is a positive correlation between periods of floodplain soil development and mesic climatic episodes identified in current paleoclimatic models for the Plains. There is also evidence for climatic variability within episodes. © 1993 John Wiley & Sons, Inc.     

Landforms and archaeological site location in the little Missouri badlands: A new look at some well-established patterns

Patterns in the distribution of archaeological sites in the Little Missouri Badlands of North Dakota have previously been attributed to prehistoric cultural preference for certain landforms. These patterns include the concentration of Plains Archaic sites in upland settings and the predominance of Late Prehistoric sites in the alluvial lowlands. An understanding of Holocene stratigraphy provides new insights into these patterns, and other spatial/temporal aspects of the archaeological record. These insights in turn illustrate the need for comprehensive stratigraphic studies prior to the formulation of prehistoric settlement models in highly eroded environments. © 1993 John Wiley & Sons, Inc.     

Geoarchaeology of stratified paleoindian deposits at the Big Eddy site,Southwest Missouri,U.S.A.

The Big Eddy site (23CE426) in the Sac River valley of southwest Missouri is a rare recorded example of distinctly stratified Early through Late Paleoindian cultural deposits. Early point types recovered from the site include Gainey, Sedgwick, Dalton (fluted and unfluted), San Patrice, Wilson, and Packard. The Paleoindian record at Big Eddy represents only a fraction of the site's prehistoric cultural record; stratified cultural deposits in alluvium above the Paleoindian components span the entire known prehistoric sequence, and terminal Pleistocene alluvium may contain pre‐Early Paleoindian cultural deposits. This study focused on the paleogeomorphic setting, stratigraphy, depositional environments, pedology, geochronology, and history of landscape evolution of the late Pleistocene and early Holocene alluvium at the site. The Paleoindian sequence is associated with a complex buried soil 2.85 m below the modern surface (T1a) of the first terrace of the Sac River valley in the site vicinity. This soil formed at the top of the early submember of the Rodgers Shelter Member (underlying the T1c paleogeomorphic surface) and contains at least 70 cm of stratified Paleoindian cultural deposits, all in floodplain and upper point‐bar facies. A suite of 36 radiocarbon ages indicates that the alluvium hosting the Paleoindian sequence aggraded between ca. 13,250 and 11,870 cal yr B.P. (11,380 and 10,180 14C yr B.P.). Underlying deposits accumulated between ca. 15,300 and 13,250 cal yr B.P. (12,950 and 11,380 14C yr B.P.). By ca. 11,250 cal yr B.P. (9,840 14C yr B.P.) the T1c paleogeomorphic surface was buried by the earliest increment of a thick sequence of overbank sheetflood facies, ultimately resulting in deep burial and preservation of the Paleoindian record. The landform‐sediment assemblage that hosts the Paleoindian and possibly earlier cultural deposits at Big Eddy is both widespread and well preserved in the lower Sac River valley. Moreover, the terminal Pleistocene and early Holocene depositional environments were favorable for the preservation of the archaeological record. © 2007 Wiley Periodicals, Inc.     

Late Pleistocene and Early Holocene lake‐level fluctuations in the Lahontan Basin,Nevada: Implications for the distribution of archaeological sites

The Great Basin of the western U.S. contains a rich record of Late Pleistocene and Holocene lake‐level fluctuations as well as an extensive record of human occupation during the same time frame. We compare spatial‐temporal relationships between these records in the Lahontan basin to consider whether lake‐level fluctuations across the Pleistocene‐Holocene transition controlled distribution of archaeological sites. We use the reasonably well‐dated archaeological record from caves and rockshelters as well as results from new pedestrian surveys to investigate this problem. Although lake levels probably reached maximum elevations of about 1230–1235 m in the different subbasins of Lahontan during the Younger Dryas (YD) period, the duration that the lakes occupied the highest levels was brief. Paleoindian and Early Archaic archaeological sites are concentrated on somewhat lower and slightly younger shorelines (_1220–1225 m) that also date from the Younger Dryas period. This study suggests that Paleoindians often concentrated their activities adjacent to large lakes and wetland resources soon after they first entered the Great Basin. © 2008 Wiley Periodicals, Inc.     

Geoarchaeology and Paleoenvironmental Context of the Burntwood Creek Rockshelter,High Plains of Northwestern Kansas,U.S.A

The first systematic geoarchaeological study of a rockshelter in Kansas yielded information about rockshelter formation, Holocene paleoenvironments, archaeological site formation processes, and prehistoric human habitation and site use. The rockshelter was carved by groundwater sapping; colluvium, alluvium, and roof‐fall debris subsequently accumulated on its floor. An assemblage of Late Archaic (∼2000–4000 ¹⁴C years before present [yr B.P.]) cultural deposits (lithic material, bone, and charcoal) is preserved in a 2‐m thick package of colluvium and alluvium in front of the shelter. Chipped stone analysis indicates that Late Archaic occupants of the shelter were using mostly local materials and resharpening their stone tools at the shelter. Stable carbon isotope and phytolith analyses indicate that a mixed C₃ and C₄ plant community existed in the study area and that it changed in composition through the late Holocene. Based on the phytolith assemblage from an unlined fire pit at the front of the shelter, Late Archaic people used local hackberry trees for fuel and/or food.     

Geoarchaeological investigations of San Mateo and Las Flores Creeks,California: Implications for coastal settlement models

The late Quaternary stratigraphy and geochronology of San Mateo and Las Flores Creeks indicates that both streams, which drain into the Pacific Ocean along the southern California coast, had a synchronous landscape history. Both San Mateo and Las Flores Creeks cut deep valleys during the late Pleistocene in response to the worldwide drop in sea level. A long period of aggradation followed as sea level rose to its present position during the late Pleistocene and Holocene. Around 500 years ago, the channels of both streams downcut into their respective floodplains creating a prominent terrace (T-2). This was followed by renewed deposition and later channel incision which created a second terrace (T-1). These channel changes are probably the result of a complex response of the fluvial system to major flooding during the late Holocene. The geologic history of these drainages provides a framework that can be used to assess the buried archaeological record along the coast and evaluate regional prehistoric settlement patterns. Based on this study, the post-4000 B.P. valley floor archaeological record along the southern California coast will be more complete and accessible, resulting in a better understanding of the spatial distribution of sites. On the other hand, the pre-4000 B.P. valley floor record lies deeply buried and inaccessible to researchers, which results in a distortion of settlement patterns before 4000 B.P. Finally, examination of post-4000 B.P. sites in the alluvium of San Mateo and Las Flores creeks yielded a pattern of large sites that were occupied extensively for multiple seasons and had considerable evidence of marine exploitation. These findings are contrary to models of cultural development along this portion of the southern California coast. © 1999 John Wiley & Sons, Inc.     

The Alluvial Geoarchaeology of the Sanyangzhuang Site on the Yellow River Floodplain,Henan Province,China

The Sanyangzhuang site, Henan Province, China, has a 12‐m‐deep stratigraphic sequence with remains from the Tang (A.D. 618–907), late Western Han (ca. 140 B.C.–A.D. 23), Warring States (475–221 B.C.), Late Neolithic or Early Bronze Age (ca. 5000–1500 B.C.), Middle Holocene, and Early Holocene times. All of the paleosols are deeply buried. We investigate four issues relevant to the archaeology of the lower Yellow River Valley. First, we confirm that the Yellow River flowed north toward Bohai Bay throughout most of the Holocene. Second, we expand understanding of Holocene paleoenvironments. Long episodes of landscape stability punctuated by brief periods of Yellow River flooding represent the dominant environmental pattern. Third, we investigate how the complex relationships between climate, culture, and the environment affect Yellow River flooding, which in turn shapes Chinese civilization and history. Flooding in late Western Han times affected a vast area of north‐central China; this catastrophe contributed to the downfall of the late Western Han Dynasty. Finally, this research sheds light on the role of Yellow River alluviation in site burial and preservation. Rapid alluviation in the region has buried many archaeological sites. Settlement pattern research needs to take seriously the limitations placed on site visibility in quickly aggrading floodplains. However, gentle alluviation has also preserved settlements and entire landscapes providing unparalleled opportunities to explore the archaeological and historical record of the lower Yellow River Valley.     

Hunter-gatherers in the nashville basin: Archaeological and geological evidence for variability in prehistoric land use

Results of intensive archaeological surveys conducted within two environmentally contrastive settings in the Nashville Basin of Tennessee demonstrate that prehistoric human activity was much more extensive in the inner Basin where the Duck River floodplain was flanked by patchy upland vegetation relative to the outer Basin where upland vegetation was more homogeneous. Vertebrate remains from caves and rockshelters show that the inner Basin supported such patchy upland vegetation throughout the known period of hunter-gatherer occupation of the area. There is close correspondance between periods when forest openings were most prevalent (i.e., Late Pleistocene/Early Holocene and Mid-Holocene) and times when prehistoric human occupation of the inner Basin was most intensive (Paleoindian and Middle Archaic). Comparisons of major artifact categories from systematic collections of various landform surfaces show that the T2 terrace was the most extensively utilized by prehistoric hunter-gatherers. the T3/valley slope, the uplands, and the T1 produced progressively lower artifact densities. Results of systematic backhoe trenching indicate that substantial Holocene aggradation accounts for the seemingly minor use of the T1.     

A deeply stratified archaeological and sedimentary sequence in the Delaware river valley of the middle Atlantic region,United States

A stratified sedimentary and archaeological sequence over seven meters thick is under investigation on Upper Shawnee Island in the Upper Delaware Valley, Monroe County, Pennsylvania. Artifact deposits identified to date include Early Archaic (7380 B.C.), possible Middle Archaic (4300/3300 B.C.), Late Archaic (1565 B.C.), and Middle and Late Woodland components. This paper focuses on the Early Archaic deposits at approximately 4.3 meters below the surface and the implications that the entire profile has for paleoenvironmental change. The sedimentary sequence represents several major changes in depositional processes. Of special interest is a dramatic decrease in landscape stability and an increase in flood depositions during the mid-Holocene, circa 4300/3300 B.C. Similar changes are evident at archaeological sites in the Middle and Lower sections of the Delaware Valley and appear to be a reflection of regional climatic change.     

Quaternary climate,environment, and the human occupation of the south-central Andes

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.).     

Prehistoric settlement and landscape change on alluvial fans in the upper Mississippi river valley

Geoarchaeological studies of alluvial fans in the northern Sny Bottom (Upper Mississippi River valley) focused on distal fan lobe processes, the effects of small-scale landscape change on prehistoric locational decisions, and the resulting structure of the archaeological record. Aerial imagery together with coring and trenching of paleochannels on distal lobes found that frequent channel avulsion (1) produced abrupt landform/habitat changes and (2) shifted the primary loci of sediment deposition on fans through time. Analysis of wood charcoal from prehistoric occupations indicates that vegetation succession during post-avulsion overbank aggradation along a new channel was characterized by a shift from Fraxinus-dominated to mesophytic forest. Results also indicate that use of fans by Early Woodland (ca. 2550–2100 B.P.) and other foragers centered on portions along active channels. Shifting depositional loci on fans led to surfaces and depositional units of varying age, and hence a complex stratigraphic record of Holocene occupations.     

Geoarchaeology and geochronology of pluvial Lake Chapala,Baja California,Mexico

Stratigraphic exposures in natural profiles, archaeological excavation units, backhoe trenches, and an uncased water well from the Laguna Seca Chapala basin in the Central Desert of Baja California (29°N, 115°W) record lake level and climate changes and provide a context for prehistoric occupation predating 9070 yr B.P. and extending through the Holocene. Lithofacies analysis points to the presence of a large (ca. 66 km²) lake prior to 9070 yr B.P., which desiccated by 7.45 ka yr B.P., promoting rapid dune growth. New dating and redefinition of stratigraphic units in the basin refutes earlier models of lacustrine history and prehistoric occupation including a proposed series of Pleistocene lake levels with associated cultural occupations. The geologic record from the Laguna Seca Chapala basin compares well with other paleoenvironmental records in southwestern North America, supporting interpretations of wet and cool conditions in Baja California during the late Pleistocene and early Holocene. © 2003 Wiley Periodicals, Inc.     

Carolina Bay geoarchaeology and Holocene landscape evolution on the Upper Coastal Plain of South Carolina

Surface water on the mainly dry, upland interfluves of the Upper Coastal Plain of South Carolina occurs currently as a sporadic distribution of shallow ponds held within Carolina bays and other small, isolated basins. At seven bays on the U.S. Department of Energy's Savannah River Site on the Upper Coastal Plain of South Carolina, we investigated Holocene changes in bay morphology, ecology, and prehistoric human activity. At Flamingo Bay, we employed archaeological survey and testing, shovel and auger testing, sediment analysis, and ground-penetrating radar to document stratigraphy and chronology of the sand rim on the eastern side of the bay. Artifact assemblage indicate changes in intensity of human use of the bay. Radiocarbon dates from a sediment core establish time scales for depositional processes at the center of the basin. Ground-penetrating radar data from the other bays indicate that the stratigraphy of all seven bays is broadly similar. We conclude that: (1) Significant modification of the bays, including rim development and basin infilling, occurred during the Holocene; (2) ponds on the early Holocene landscape were larger and more permanent than at present; (3) early Holocene climate, as indicated by both depositional processes and human activity, was not characterized by prolonged periods of extremely dry conditions; and (4) fluvial-centric models of terminal Pleistocene—early Holocene human adaptations require revision to include intensive use of isolated upland ponds. © 1996 John Wiley & Sons, Inc.     

Holocene landscape evolution and the development of models for human interaction with the environment: An example from the mississippi headwaters region

Integration of a record of Holocene landscape evolution with the cultural record from a multicomponent archaeological site in northern Minnesota has fostered the development of a regional model of human interaction with the changing physical environment. Excavation of 21-CA-169 near Nushka Lake revealed two components, an aceramic Archaic zone where processing of large mammals was the major activity and an upper zone with artifacts suggestive of wild rice processing. Seasonal occupation of the lower zone occurred during a period of falling regional lake levels resulting from natural stream network evolution. The upper zone represents human occupation in a physical and biological setting that was quite different than during earlier occupation. Integration of the geomorphic history of the region along with an interpretation of the types of cultural activities occurring on the changing landscape have provided a model to understand land use and to predict the location of other sites. © 1993 John Wiley & Sons, Inc.     

Holocene survival of the wild horse in Europe: a matter of open landscape?

The wild horse Equus ferus was one of the most frequent species of the Late Pleistocene large ungulate fauna in Eurasia and played an important role in the subsistence of human groups, especially at the end the Late Glacial. It is frequently assumed that E. ferus became extinct in Europe at the beginning of the Holocene because of the development of woodlands and loss of open habitats. Because of its preference for open habitats and in spite of its adaptability, the appearance or disappearance of the wild horse could therefore be a suitable palaeoecological indicator for the opening of the Holocene primeval woodlands. We revised the dating and reliability of the subfossil record and dated several bones by atomic mass spectrometry ¹⁴C dating. From the beginning of the Holocene (9600 cal a BC) to the end of the Atlantic Period (3750 cal a BC) there are 207 archaeological sites with wild horse records available in Europe. E. ferus survived the Pleistocene Holocene transition in Europe, but the spatiotemporal dynamics of populations fluctuated remarkably in the early and middle Holocene. Small and sparse populations increasingly became extinct during the early Holocene, until between 7100 and 5500 cal a BC the wild horse was almost absent in central parts of the European Lowlands. Particular conditions in natural open patches in the canopy forests, chalklands and floodplains may have maintained the local survival of the horse in some regions of the Lowlands, however. In the Late Atlantic, between 5500 and 3750 cal a BC the range of the wild horse was again extended. It re‐immigrated into central and western Europe, probably as a consequence of increasing landscape opening by Neolithic peoples. The data presented here may be a valuable part of the debate on the degree of openness of the early and middle Holocene landscape. Copyright © 2011 John Wiley & Sons, Ltd.     

Radiocarbon dates and the genesis of phytogenic near-shore sediments on St. Catherines Island,Georgia, USA

St. Catherines Island consists of a complex association of Pleistocene and Holocene sediments. The geographic location of the island at the center of Georgia Bight, a prominent re-entrant in the coastline of the southeastern USA, has resulted in the development of a very complex depositional and erosional history. For over 40,000 years the island has experienced a variety of physical, biological, and anthropological changes brought about by climatic, biotic, depositional, and anthropogenic events. Sedimentary deposits have been studied using diverse research tracks including palynology, dendrology, sedimentology, geophysics, and radiocarbon chronology, as well as archaeological techniques. This research focused on the interpretation of environments of deposition of strata that are exposed within the present surf zone, yet which bear the distinct signatures of upland/inland environments of deposition. Data derived from Late Pleistocene and Holocene accumulations of peat and mollusc- and wood-bearing muddy strata of certain on-shore and near-shore origins reveal diverse events relating to shoreline dynamics, plant community changes, and net shoreward migration of this island during the Late Holocene.     

安徽及邻区史前地震研究进展

历史地震可靠性检验分析显示,安徽省及邻区M_S 5及以上地震完整记录起自1336年,这以前地震记载大部分丢失。近年来,地震和考古部门利用大规模考古和工程开挖契机,编录识别分析了晚第四纪尤其是新石器时代以来构造变形遗迹。结果表明,在皖西南的西周-春秋期和皖北大汶口晚期及豫南东周期文化层中分别发现史前地震遗迹。郯庐断裂带苏皖交界地区段落,自晚更新世以来曾发生数次以斜向平移逆冲为主要方式的快速变形事件,后者得到微观研究方面的证实。研究结果一定程度上弥补了地震史料记载的局限,并丰富了考古和史前地震乃至地震预测的研究方法。     

Floodplain formation processes and archaeological implications at the Grand Banks site,lower Grand River,southern, Ontario

Processes of floodplain development and the record of Princess Point cultural occupation (A.D. 500–1000) were examined at the Grand Banks site in the lower Grand River of southern Ontario. The Princess Point Complex of the early Late Woodland is significant because it represents the first shift to horticulture in this region in which inhabitants made significant use of floodplains. The floodplain of the lower Grand River has been constructed primarily via vertical accretion of sediment in a low energy environment conducive to limited erosion and slow burial of middle and late Holocene sediments. At this site, cultural materials are preferentially preserved in two buried soils each corresponding to relatively stable periods of valley infilling at or before 3200 B.P. and 1500 B.P. (¹⁴C years). Initial formation of the floodplain and subsequent stability of the floodplain surface can be tied to middle Holocene, and later, base-level fluctuations in Lake Erie. Understanding floodplain development is crucial in determining the linkages between settlement pattern and chronology, and, conversely, the archaeological record in floodplain settings provides important contemporary data for modeling floodplain geomorphological processes. © 1997 John Wiley & Sons, Inc.     

Geoarchaeology of dissected loess uplands in Western Illinois

Late Quaternary hillslope and valley evolution of the loess-mantled uplands between the Illinois and Mississippi Rivers has produced a landscape composed of surfaces of different ages. Archaeological remains occur in a variety of geological contexts, including intact surfaces that predate the artifacts upon them, as lag on surfaces formed by subsequent erosion, and buried within alluvium, colluvium, and upland loess soil profiles. Holocene channel belts are largely confined to trenches formed by deep stream incision during the late Pleistocene, and much of the alluvial record is intact, especially in valleys with aggraded floodplains. Modest Holocene hillslope retreat in backslope and shoulder landscape settings and temporary storage of footslope colluvium is documented at some sites. Historic land use practices have resulted in severe hillslope retreat and near complete burial of Holocene valleys with a 0.5-1-m-thick veneer of historic sediment. © 1993 John Wiley & Sons, Inc.