Quaternary Research Papers - Academia.edu (original) (raw)

The large mammal and micromammal assemblages from Paleolithic cave sites in northwestern Croatia (Veternica, Velika peć ina, and Vindija) suggest the presence of relatively temperate environments without dramatic oscillations in faunal... more

The large mammal and micromammal assemblages from Paleolithic cave sites in northwestern Croatia (Veternica, Velika peć ina, and Vindija) suggest the presence of relatively temperate environments without dramatic oscillations in faunal composition during MIS 3, and possibly also including MIS 2 and 4. Species such as woolly rhinoceros, arctic fox, varying hare, and saiga antelope were not present, and the micromammal assemblages show that all taxa are indicators of a temperate, continental climate characterized by somewhat less forested conditions than those present today. Nonetheless, the region does not appear to have served as a refuge for mammals whose distribution today is north of Croatia. The region appears to have had a fairly diverse and productive mammal fauna, which in turn could have supported significant hominin populations. Faunal composition did not dramatically change across the Middle-Upper Paleolithic transition (ca. 40 000-30 000 BP). The apparent stability in mammalian faunas could be owing to several factors: A) a depositional/preservational bias for warmer phases, B) dampered climatic oscillations in the region, C) faunal communities buffered from climatic oscillations owing to microclimate, topography, etc. Resolution of these factors requires further research.

This paper presents the results of the archaeozoological and taphonomic study on a sample of about 55,000 bone remains collected in the Gravettian occupation levels (Layer D) of Riparo Mochi (Balzi Rossi, Ventimiglia -Italy). Humans are... more

This paper presents the results of the archaeozoological and taphonomic study on a sample of about 55,000 bone remains collected in the Gravettian occupation levels (Layer D) of Riparo Mochi (Balzi Rossi, Ventimiglia -Italy). Humans are the main agent responsible for the accumulation of the faunal remains as indicated by the presence of impact cones, butchering striae, burned bones and by the almost complete absence of carnivore traces. The faunal assemblage includes an association rich in artiodactyls and, to a lesser extent, lagomorphs, rodents, and carnivores adapted to different environments and climates. Hunting focused mainly on red deer and ibex, and the site was occupied mainly during winterspring. The whole faunal sample was divided into "phases" in order to recognize possible paleontological, paleoecological, and palaeoeconomic variations which may have occurred in the area of the rock-shelter during the investigated period.

The decline and disappearance of a range of giant marsupials, reptiles and birds from the Australian landscape during the last Glacial cycle continues to capture the imagination of both researchers and the general public. The events... more

The decline and disappearance of a range of giant marsupials, reptiles and birds from the Australian landscape during the last Glacial cycle continues to capture the imagination of both researchers and the general public. The events hinted at in the Australian fossil sequences appear to be mirrored on other continents through similar time periods, though the exact cause or sequence of extinctions remains largely unresolved. In recent years debate over megafaunal extinctions in Australia has been dominated by reports that humans were the primary drivers, leading some to assert that it is no longer a question of whether humans drove these extinctions, only how. Following the review of Wroe and Field, new reports have been published that claim support for a human-driven extinction (HDE). On closer scrutiny however, the key sites and samples lack firm contextual data and/or clear provenance. These studies fail to prove a key tenet of the HDE e that all, or even most now-extinct species were present at the time of human colonization of the continent. As compared with the easy assertion 5 years ago that this had been established, there are now more faunal species (c. 69% of total known to have become extinct) that cannot be placed within 50e100 ka of human arrival. There are still only two sites that demonstrate a coexistence of humans with some species of megafauna e Nombe Rockshelter in the PNG highlands and Cuddie Springs in the semi-arid southeast of Australia. If there is so little empirical evidence for coexistence or association of megafauna with humans, then support for an HDE through overhunting and ecosystem disruption is seriously compromised. Furthermore, the popularly cited "extinction window", proposed as c. 51e39 ka when the HDE is argued to occur, is still only a theoretical construct. There is no clear evidence indicating that this period was particularly significant in terms of faunal loss. At present, the great majority of 'Pleistocene' sites remain poorly dated and the understanding of faunal turnover through this epoch is almost non-existent. Small datasets, poorly constructed hypotheses and assertive rhetoric are the prominent features of current discussions on a human role in megafaunal extinctions. Importantly, it is yet to be established whether the extinctions are an archaeological problem. The sparse fossil record known from Australia hampers a clear resolution as to how and when the megafauna disappeared, a situation likely to continue into the near future.

The Whakatane Tephra, a rhyolitic tephra erupted ca. 5500 cal. BP from Okataina Volcanic Centre, central North Island, has been identified on the Chatham Islands which lie ~900 km east of Christchurch, New Zealand. The visible tephra... more

The Whakatane Tephra, a rhyolitic tephra erupted ca. 5500 cal. BP from Okataina Volcanic Centre, central North Island, has been identified on the Chatham Islands which lie ~900 km east of Christchurch, New Zealand. The visible tephra layer, ~5 mm in thickness and preserved within peat on Pitt Island, was identified using both radiocarbon dating and analysis of glass shards by electron microprobe. Whakatane Tephra is the first Holocene tephra to be identified on the Chatham Islands, and it is the most distal Holocene tephra yet recorded in the New Zealand region, being ~850 km from source. The Pitt Island occurrence extends the tephra's dispersal area markedly, by an order of magnitude, possibly to ~300,000 km 2 . An estimated dispersal index (D) of approximately 10 5 km 2 indicates that the eruption generated a very high plinian column, possibly exceeding ~30 km in height, with strong winds blowing the ash plume southeastwards.This new discovery of distal Whakatane Tephra as a thin but visible layer strongly implies that cryptotephras are likely to bepreserved on the Chatham Islands and within adjacent ocean floor sediments. Therefore the potential exists to develop enhanced cryptotephrostratigraphic records from these distal areas, which in turn would help facilitate precise correlation via tephrochronology of palaeoenvironmental records (such as NZ-INTIMATE) from mainland New Zealand, the southwest Pacific Ocean, and the Chatham Islands.

Oxygen-18 (18O) values of sediment from the Wilson Creek Formation, Mono Basin, California, indicate three scales of temporal variation (Dansgaard–Oeschger, Heinrich, and Milankovitch) in the hydrologic balance of Mono Lake between 35,400... more

Oxygen-18 (18O) values of sediment from the Wilson Creek Formation, Mono Basin, California, indicate three scales of temporal variation (Dansgaard–Oeschger, Heinrich, and Milankovitch) in the hydrologic balance of Mono Lake between 35,400 and 12,90014C yr B.P. During this interval, Mono Lake experienced four lowstands each lasting from 1000 to 2000 yr. The youngest lowstand, which occurred between 15,500 and 14,00014C yr B.P., was nearly synchronous with a desiccation of Owens Lake, California. Paleomagnetic secular variation (PSV) data indicate that three of four persistent lowstands occurred at the same times as Heinrich events H1, H2, and H4.18O data indicate the two highest lake levels occurred ∼18,000 and ∼13,10014C yr B.P., corresponding to passages of the mean position of the polar jet stream over the Mono Basin. Extremely low values of total inorganic carbon between 26,000 and 14,00014C yr B.P. indicate glacial activity, corresponding to a time when summer insolation was much reduced.

Grain size analyses of three hilltop, primary eolian loess sequences in the Negev desert, southern Israel, show a bimodal grain-size distribution at 50-60 μm and 3-8 μm. Using analyses of mineralogy and OSL ages we demonstrate that the... more

Grain size analyses of three hilltop, primary eolian loess sequences in the Negev desert, southern Israel, show a bimodal grain-size distribution at 50-60 μm and 3-8 μm. Using analyses of mineralogy and OSL ages we demonstrate that the coarse mode is composed mostly of quartz grains and its relative magnitude increases regionally with time, suggesting an enhancement of a time-transgressive proximal dust source compared to a distal, Saharan fine-grain dust. The only proximal dust source for large amount of coarse silt quartz grains is the sands that advanced into Sinai and the Negev concurrently with the loess accretion during the late Pleistocene as a result of the exposure of the Mediterranean shelf. We therefore propose that the coarse silt quartz grains were formed through eolian abrasion within the margins of an advancing sand sea. This relationship between desert sand seas as a source for proximal coarse dust and desert margin loess deposits can be applicable to other worldwide deserts such as Northern Africa, China and Australia.

This paper investigates the stable isotopic composition from late Pleistocene–Holocene (~ 13 to ~ 10.5 cal ka BP) shells of the land snail Helix figulina, from Franchthi Cave (Greece). It explores the palaeoclimatic and... more

This paper investigates the stable isotopic composition from late Pleistocene–Holocene (~ 13 to ~ 10.5 cal ka BP) shells of the land snail Helix figulina, from Franchthi Cave (Greece). It explores the palaeoclimatic and palaeoenvironmental implications of the isotope palaeoecology of archaeological shells at the time of human occupation of the cave. Modern shells from around the cave were also analysed and their isotopic signatures compared with those of the archaeological shells. The carbon isotope composition of modern shells depicts the consumption of C3 vegetation. Shell oxygen isotopic values are consistent with other Mediterranean snail shells from coastal areas. Combining empirical linear regression and an evaporative model, the δ18Os suggest that modern snails in the study area are active during periods of higher relative humidity and lower rainfall δ18O, probably at night. Late glacial and early Holocene δ18Os show lower values compared to modern ones. Early Holocene δ18Os ...

Pollen data from 47 sequences in various areas of Belarus have been used, aimed at reconstructing the initial spread and further development of early arable farming. Three stages have been identified, based on the appearance of the pollen... more

Pollen data from 47 sequences in various areas of Belarus have been used, aimed at reconstructing the initial spread and further development of early arable farming. Three stages have been identified, based on the appearance of the pollen of cultural cereals in the spectra (Cerealia undif. pollen, Triticum, Hordeum and Secale). First signals of introduction of early farming were recorded in southwestern Belarus at 6600-6000 BP, apparently in relation to the Linear Pottery Culture. Spatial-temporal frameworks of early agriculture signatures: southwest -6600-6000 BP; central regions-5000-4200 BP; north-3400-2700 BP.

A 5000-yr stratigraphic record containing fossil pollen, charcoal, and bones of the extinct Quaternary megafauna from Andolonomby, a hypersaline pond in arid southwestern Madagascar, shows evidence for climatic desiccation beginning about... more

A 5000-yr stratigraphic record containing fossil pollen, charcoal, and bones of the extinct Quaternary megafauna from Andolonomby, a hypersaline pond in arid southwestern Madagascar, shows evidence for climatic desiccation beginning about 3000 yr B.P. Pollen spectra shift at this time from primarily arboreal taxa characteristic of forests and woodlands of more mesic western Madagascar, to wooded savanna typical of somewhat drier localities. Between 3000 and 2000 yr B.P., the site became increasingly arid. Charcoal and pollen evidence indicates that increased fire and disturbance occurred at the site beginning ca. 1900 yr B.P., probably signaling the beginning of human settlement in the area. The fossil record suggests that various human and natural factors on the island may have interacted in the subsequent millennium to culminate in the extinction of the entire endemic megafauna.

A review of published stratigraphic records of pollen, sediment grain size, diatoms, and organic matter composition from Lake Biwa, Japan, identifies four pre-Holocene episodes of milder climate, increased surface runoff, and enhanced... more

A review of published stratigraphic records of pollen, sediment grain size, diatoms, and organic matter composition from Lake Biwa, Japan, identifies four pre-Holocene episodes of milder climate, increased surface runoff, and enhanced aquatic productivity, indicating intervals of warmer and wetter conditions which are interpreted as being interglacial. Correlation of these episodes to times of marine interglacial periods revises the age scale of the Lake Biwa sediment sequence which has been based on fission-track dating. The revised chronostratigraphic scale proposes an age of ca. 430,000 yr B.P. for the base of the 250-m-thick T Bed instead of the former age of ca. 700,000 yr B.P.

Structural analysis plays a crucial role during the designing of mechanism. Structural analysis of kinematic chain deals with connection among the members of kinematic chain and its mobility. In the present work efforts has been made to... more

Structural analysis plays a crucial role during the designing of mechanism. Structural analysis of kinematic chain deals with connection among the members of kinematic chain and its mobility. In the present work efforts has been made to provide adequate solution of structural analysis of kinematic chain by considering the example of twelve link mechanism. With the help of graph theory the structure of the kinematic chain is shown by its kinematic graph in which the links shows the vertices and the joints shows the edges. The kinematic graph is then represented by incidence matrix or adjacency matrix. This matrix shows the connection between the links. Then a simple method is applied on the matrix to determine the coefficient of characteristic polynomial equation. Finally for mobility analytic test is performed to find whether kinematic chain possess total, fractioned, or partial degree of freedom.

Sedimentary charcoal particles from lakes are commonly used to investigate fire history. Fire-history reconstructions are based on measuring the surface area or counting the number of charcoal fragments in adjacent samples. Recently, the... more

Sedimentary charcoal particles from lakes are commonly used to investigate fire history. Fire-history reconstructions are based on measuring the surface area or counting the number of charcoal fragments in adjacent samples. Recently, the volume of charcoal particles was advised as a more accurate method for quantifying past charcoal production. Large charcoal datasets, used to synthesize global fire history, include these different types of charcoal measurements and implicitly assume that they provide comparable firehistory information. However, no study has demonstrated that this assumption is valid. Here we compare fire-frequency reconstructions based on measurements of charcoal area and number, and estimates of charcoal volume from two lake sediment records from the eastern Canadian boreal forest. Results indicate that the three proxies provide comparable fire-history interpretations when using a locally defined threshold to identify fire events.

Two mammoth sites from the central Great Plains of North America, each containing one adult Columbian mammoth (Mammuthus columbi), were excavated from Last Glacial Maximum (LGM) loess and fine-grained alluvial deposits, respectively.... more

Two mammoth sites from the central Great Plains of North America, each containing one adult Columbian mammoth (Mammuthus columbi), were excavated from Last Glacial Maximum (LGM) loess and fine-grained alluvial deposits, respectively. Taphonomic data from both sites indicate that the mammoth skeletons exhibit numerous spirally fractured limb elements. Dynamic loading points are present on midshafts of large limb bones. Bone flakes produced from the partial thickness of thick cortical bone are also present. Hypotheses of carnivore activity, mammoth trampling, and human-induced fracturing are evaluated as possible causes of the fractured limb bone. Testing the hypotheses using modern data from actualistic taphonomic studies of elephant skeletons, paleontological data from two proboscidean natural death sites, experimental data from elephant bone fracturing, and archaeologically derived data concerning late Pleistocene human modification of mammoth limb bone indicates that the first two hypotheses can be rejected, while the third hypothesis is supported. r

Human land-use has considerably shaped the landscape of northwestern Germany over the past millennia. Deforestation and agriculture created a predominantly open scenery preserved until today with only a few remnants of former landscape... more

Human land-use has considerably shaped the landscape of northwestern Germany over the past millennia. Deforestation and agriculture created a predominantly open scenery preserved until today with only a few remnants of former landscape elements such as woodlands, peat bogs or heath lands. Lake sediments serve as unique natural archives to reconstruct the extent and timing of prehistoric human impact on the terrestrial environment and lacustrine ecosystems as well as to trace the history of particular landscape elements.

A new scale has been introduced by the INQUA Subcommission on Paleoseismicity for evaluating the intensity of an earthquake by examining the earthquake environmental effects. The definitions of the intensity degrees, provided by the INQUA... more

A new scale has been introduced by the INQUA Subcommission on Paleoseismicity for evaluating the intensity of an earthquake by examining the earthquake environmental effects. The definitions of the intensity degrees, provided by the INQUA scale, are based solely on the ground effects such as liquefaction, rockfalls, and ground fissures. The Lefkada (western Greece) earthquake of 2003 (Mw ¼ 6.2, Ms ¼ 6.4) has been selected as a case study for testing the accuracy and reliability of the INQUA scale. The evaluated intensity parameters of the 2003 earthquake based on the MM and EMS scales are compared, with the one assessed using the ''INQUA intensity'' scale. Furthermore, these degrees of ''INQUA intensity'' were compared with the values of intensity of past events. From this comparison, we conclude that in Greece, in urban areas developed according to the provisions of the upgraded seismic codes, the evaluated intensities based on EMS scale may underestimate the ground shaking. In order to assess accurately the seismic hazard of an area, the use of the INQUA scale in combination with the EMS scale is suggested.

High rates of coastal retreat characterise the weakly cemented Plio-Pleistocene rocks and sediments which form much of the cliffed coastline of East Anglia, southern North Sea. The accurate establishment of sediment losses from these... more

High rates of coastal retreat characterise the weakly cemented Plio-Pleistocene rocks and sediments which form much of the cliffed coastline of East Anglia, southern North Sea. The accurate establishment of sediment losses from these cliffs has a regional significance as these sediments are important in maintaining beaches and nearshore bank systems and in feeding nearshore sediment transport pathways. However, the high spatial and temporal variability of cliff failure processes in such materials necessitates fine-scale integration of alongshore variations in cliff retreat over a series of well-established time periods to accurately define cliffline recession rates and sediment volume inputs to the nearshore system. This study applied the DSAS (Digital Shoreline Analysis System) within the GIS software package ArcMap to digitised, georeferenced positions of former shorelines, obtained from historic maps and aerial photographs (after 1992), for the sections of Benacre-Southwold and Dunwich-Minsmere on the Suffolk coast of East Anglia, UK; transects were cast every 10 m alongshore, producing very high spatial resolution upon which to assess shoreline retreat (over 1000 transects along 11 km of shoreline). Long-term (1883-2008) mean shoreline retreat rates varied between 2.3-3.5 m a-1 (Benacre-Southwold) and 0.9 m a-1 (Dunwich-Minsmere). For six cliffed subunits within these larger coastal sections, spatial variations in cliffline recession rates for shorter time intervals (at ca. 20-year intervals) within this longer (125 year) period were established. The combination of recession rates with photogrammetric methods of obtaining cliff top elevation at the same spatial resolution, available using aerial photographs and digital terrain models, along with cliff sediment composition, allowed the calculation of sediment volumetric inputs from cliff retreat in the period 1992-2008. Re-assessment of the magnitude and location of sediment inputs into the nearshore zone, their interaction with regional sediment transport and the growth of inshore bank systems, as well as the implications for contemporary and near-future coastal management strategies are discussed with reference to this section of the Suffolk coast. Temporal and spatial variations in recession rates and sediment release from soft rock cliffs,

Des dépôts alluviaux datant du Tardiglaciaire et du début de l'Holocène ont été découverts dans la plaine du Caudeau, petit affluent de la Dordogne, à La Brunetière sur la commune de Pombonne (Dordogne) à l'occasion de travaux... more

Des dépôts alluviaux datant du Tardiglaciaire et du début de l'Holocène ont été découverts dans la plaine du Caudeau, petit affluent de la Dordogne, à La Brunetière sur la commune de Pombonne (Dordogne) à l'occasion de travaux d'archéologie préventive. Leur analyse permet de renouveler nos connaissances sur l'évolution des cours d'eau en Aquitaine pendant cette période charnière. Ils montrent en particulier que les principales phases de métamorphose alluviale décrites dans le nord de l'Europe se sont également produites dans cette région de manière à peu près synchrone, pour autant que l'on puisse en juger d'après les dates disponibles. Deux phases majeures d'incision aux dépens de la nappe alluviale à galets pléniglaciaire sont identifiables. La première intervient pendant une phase très précoce du Bølling, soit avant 12 700 ± 45 BP, dans un environnement steppique. L'abandon rapide du chenal, associé à du soutirage karstique, permet ensuite l'installation d'un petit lac colmaté par des argiles avec quelques intercalations tourbeuses riches en macrorestes végétaux (bouleau nain, saule). L'image de la végétation donnée aussi bien par les pollens que par la faune de mollusques et d'insectes est celle d'une steppe encore très ouverte à armoise et genévriers, alors que les paléotempératures estivales indiquées par les insectes sont déjà proches de celles connues actuellement dans la région. Des paléotempératures hivernales sensiblement plus froides que les actuelles (-20 à 5°C) renvoient cependant l'image d'un climat à caractère plus continental. Les dépôts lacustres sont ensuite recouverts par une couche de sables d'inondation attribués au Dryas moyen et/ou récent. L'assèchement du chenal et le développement d'un sol hydromorphe pourrait correspondre respectivement soit à l'Allerød, soit au tout début de l'Holocène. La seconde phase d'incision est attribuée au Préboréal et tronque la séquence tardiglaciaire ; elle est associée à un style alluvial à chenaux anastomosés. L'abandon de la majorité des chenaux pendant le Boréal marque la réduction du lit à un chenal unique sinueux, comparable à celui qui caractérise le Caudeau actuel. Une industrie lithique de type Magdalénien supérieur a également été découverte sur la berge du chenal tardiglaciaire. L'industrie recueillie est exclusivement taillée dans le silex local maestrichtien. Elle comprend environ 200 éclats et 800 petits restes de taille, pour seulement 15 lames de plein débitage et 6 outils (sans aucun microlithe). L'utilisation exclusive d'un percuteur minéral tendre, la morphologie du nucléus laminaire, la rectitude des petites lames, les 2 lames appointées sont autant de caractères qui évoquent le stade ultime du Magdalénien supérieur, tel qu'il est connu plus en amont le long de la Dordogne sur les sites de la Gare de Couze et du Moulin du Roc.

The long-lived (about 20 yr) bryozoan Adeonellopsis sp. from Doubtful Sound, New Zealand, precipitates aragonite in isotopic equilibrium with seawater, exerting no metabolic or kinetic effects. Oxygen isotope ratios (y 18 O) in 61... more

The long-lived (about 20 yr) bryozoan Adeonellopsis sp. from Doubtful Sound, New Zealand, precipitates aragonite in isotopic equilibrium with seawater, exerting no metabolic or kinetic effects. Oxygen isotope ratios (y 18 O) in 61 subsamples (along three branches of a single unaltered colony) range from À0.09 to +0.68xPDB (mean = +0.36xPDB). Carbon isotope ratios (y 13 C) range from +0.84 to +2.18x PDB (mean = +1.69xPDB). Typical of cool-water carbonates, y 18 O-derived water temperatures range from 14.2 to 17.5 jC. Adeonellopsis has a minimum temperature growth threshold of 14 jC, recording only a partial record of environmental variation. By correlating seawater temperatures derived from y 18 O with the Southern Oscillation Index, however, we were able to detect major events such as the 1983 El Niño. Interannual climatic variation can be recorded in skeletal carbonate isotopes. The range of within-colony isotopic variability found in this study (0.77xin y 18 O and 1.34 in y 13 C) means that among-colony variation must be treated cautiously. Temperate bryozoan isotopes have been tested in less than 2% of described extant species -this highly variable phylum is not yet fully understood.

The fossil remains of 43 bowhead whales were mapped on the raised beaches of western Wollaston Peninsula, Victoria Island, Canadian Arctic, near the historic summer range limit of the Bering Sea stock in the Beaufort Sea. The elevations... more

The fossil remains of 43 bowhead whales were mapped on the raised beaches of western Wollaston Peninsula, Victoria Island, Canadian Arctic, near the historic summer range limit of the Bering Sea stock in the Beaufort Sea. The elevations and radiocarbon ages of the remains demonstrate that the bowhead ranged commonly into the region following the submergence of Bering Strait at ca. 10,000 14 C yr B.P. until ca. 8500 14 C yr B.P. During the same interval, bowheads ranged widely from the Beaufort Sea to Baffin Bay. Subsequently, no whales reached Wollaston Peninsula until ca. 1500 14 C yr B.P. Late Holocene populations evidently were small, or occupations were brief, in comparison to those of the early Holocene. Although the late Holocene recurrence may relate to the expansion of pioneering Thule whalers eastward from Alaska, there are few Thule sites and limited evidence of Thule whaling in the area surveyed to support this suggestion. C 2001 University of Washington.

This study represents the first detailed joined colorimetric and rock magnetic investigation on a loess epaleosol sequence in the Vojvodina region, Northern Serbia. The aim of this paper is to derive new information on the Late... more

This study represents the first detailed joined colorimetric and rock magnetic investigation on a loess epaleosol sequence in the Vojvodina region, Northern Serbia. The aim of this paper is to derive new information on the Late Pleistocene paleoenvironment from a high resolution multi-proxy assessment of the iron mineralogical composition at the Orlovat loess paleosol sequence. The Orlovat section is the first site from the Banat loess region analyzed for Quaternary paleoclimate information, and accordingly it is the easternmost loess section in the Serbian loess region studied. In contrast to other Serbian sites, the Orlovat site is not located in a plateau. Rock magnetic analysis and the luminescence-dating based chronology revealed active slope processes at this site during the Late Pleistocene. This is the most strikingly evidenced by the absence of a Middle Wurmian (MIS 3) interstadial pedocomplex, present as marker horizon in the Serbian plateau-loess sites.

Several di!erent sources of evidence have been used to support a recent African origin for our species. It is commonly assumed that these sources of evidence support the same recent African origin. However, a close examination of the... more

Several di!erent sources of evidence have been used to support a recent African origin for our species. It is commonly assumed that these sources of evidence support the same recent African origin. However, a close examination of the evidence available from four sources, including paleontology, archaeology, the level of human genetic variation, and the geographic structure of human genetic variation, shows that this is not the case. Each of these in e!ect supports a di!erent recent African origin, and no hypothesis of a recent origin is compatible with more than two of them at a time. In contrast, all of these sources of evidence may be consistent with a multiregional model for our recent evolution.

A wide variety of environmental records is necessary for analysing and understanding the complex Late Quaternary dynamics of permafrost-dominated Arctic landscapes. A NE Siberian periglacial key region was studied in detail using sediment... more

A wide variety of environmental records is necessary for analysing and understanding the complex Late Quaternary dynamics of permafrost-dominated Arctic landscapes. A NE Siberian periglacial key region was studied in detail using sediment records, remote sensing data, and terrain modelling, all incorporated in a geographical information system (GIS). The study area consists of the Bykovsky Peninsula and the adjacent Khorogor Valley in the Kharaulakh Ridge situated a few kilometres southeast of the Lena Delta. In this study a comprehensive cryolithological database containing information from 176 sites was compiled. The information from these sites is based on the review of previously published borehole data, outcrop profiles, surface samples, and our own field data. These archives cover depositional records of three periods: from Pliocene to Early Pleistocene, the Late Pleistocene and the Holocene. The main sediment sequences on the Bykovsky Peninsula consist of up to 50 m thick ice-rich permafrost deposits (Ice Complex) that were accumulated during the Late Pleistocene. They were formed as a result of nival processes around extensive snowfields in the Kharaulakh Ridge, slope processes in these mountains (such as in the Khorogor Valley), and alluvial/proluvial sedimentation in a flat accumulation plain dominated by polygonal tundra in the mountain foreland (Bykovsky Peninsula). During the early to middle Holocene warming, a general landscape transformation occurred from an extensive Late Pleistocene accumulation plain to a strongly thermokarst-dominated relief dissected by numerous depressions. Thermokarst subsidence had an enormous influence on the periglacial hydrological patterns, the sediment deposition, and on the composition and distribution of habitats. Climate deterioration, lake drainage, and talik refreezing occurred during the middle to late Holocene. The investigated region was reached by the post-glacial sea level rise during the middle Holocene, triggering thermo-abrasion of ice-rich coasts and the marine inundation of thermokarst depressions.

To demonstrate the viability of using slug-test-analysis techniques to interpret recovery data in large-diameter, hand-dug wells, 37 wells representing a range of hydraulic conductivity and located in unconfined and weathered chalk and... more

To demonstrate the viability of using slug-test-analysis techniques to interpret recovery data in large-diameter, hand-dug wells, 37 wells representing a range of hydraulic conductivity and located in unconfined and weathered chalk and marl and confined alluvium in North-Central Texas were tested. Recovery data were analyzed by means of a numerical model, two semiempirical methods developed especially for interpreting recovery data from large-diameter hand-dug wells, and different slug-test-analysis methods that have different shape factors describing well geometry. Most hydraulic-conductivity values estimated by slug-test methods are within an order of magnitude of values that are estimated by using a numerical model or methods derived specifically for hand-dug wells. Because of the unique geometry of hand-dug wells (diameters on the same order as well lengths), care must be taken to ensure that the proper shape factors are used with slug-test methods. Because of the substantial well storage in hand-dug wells, considerable time may be required to lower the water level to the desired position, especially if pump capacity is limited. This pumping time results in a noninstantaneous withdrawal of water from the aquifer, which violates one of the assumptions of slug-test-interpretation methods. However, in low-permeability environments, reasonable results can still be attained if water removed from the well sources from well storage or if recovery time is considerably longer than pumping time.

Reflectance spectrophotometry potentially provides a rapid method of investigating the changing characteristics and composition of marine sediments. Recognizing this, the Ocean Drilling Program has permanently deployed a commercially... more

Reflectance spectrophotometry potentially provides a rapid method of investigating the changing characteristics and composition of marine sediments. Recognizing this, the Ocean Drilling Program has permanently deployed a commercially available, handheld spectrophotometer, the Minolta CM-2002, aboard the JOIDES Resolution. The present study evaluated shipboard spectral data obtained from Amazon Fan cores during Leg 155 using the Minolta instrument. These data were compared to spectra measured from comparable Leg 155 core samples using a shore-based, research-grade, Perkin-Elmer Lambda 6 spectrophotometer. The spectral signal is muted in the percent-reflectance curves from the wet sediments analyzed aboard ship when compared to percent-reflectance curves generated from dry core samples on shore. However, when both sets of reflectance curves are processed using a first-derivative transformation, shipboard and shore-based analyses are quite similar and suggest that useful, accurate spectral data can be obtained from wet core sediments at sea. This observation is further supported by factor analysis of parallel (shipboard vs. shore-based) data sets (400-700 nm) produced by the two instruments. The same four factors are present in both data sets, but do not necessarily explain a similar amount of variance. These factors are related to hematite plus goethite, clay minerals, organic matter, and carbonate content. The shore-based spectral data set was subjected to further factor analysis to determine if additional compositional information could be extracted using the increased accuracy and extended wavelength range (250-850 nm) of the laboratory instrument. This analysis produced one additional factor, probably chlorite; separated hematite and goethite into two factors; and clarified the nature of the clay mineral factor as probably a combination of illite and montmorillonite. By calculating factor scores, semiquantitative estimates of concentrations of variations of these sediment components were calculated downhole for several Leg 155 sites. The Amazon Fan sediments represent a rigorous test of the spectral technique because most of the sediments are dark and show little variation in the visible region of the electromagnetic spectrum. Nevertheless, it was possible to extract compositional information from the spectra. Our investigations also lead us to make the following important recommendations for using the Minolta CM-2002 spectrophotometer at sea. First, if wet core surfaces must be covered with plastic film during spectral measurements to protect the instrument, only Glad Cling Wrap (a brand of clear plastic food wrap) should be used because this brand does not significantly distort the spectra of the sediments. Second, when calibrating the Minolta instrument, the white calibration cap should not be covered by the clear plastic wrap used to cover the cores. Third, the Minolta instrument should be set to exclude the specular component (SCE setting) for all measurements, and the optional granular-materials cover for the instrument (CM-A40) should not be used. These recommendations will ensure that the spectral data can be compared directly to data generated by laboratory-grade spectrophotometers.

Cone Pond, New Hampshire, is an acidic (pH = 4.5) clearwater lake that is currently fishless. Historical records indicate declining fish populations between 1951 and 1966, but paleolimnological work using diatoms failed to find evidence... more

Cone Pond, New Hampshire, is an acidic (pH = 4.5) clearwater lake that is currently fishless. Historical records indicate declining fish populations between 1951 and 1966, but paleolimnological work using diatoms failed to find evidence for further recent acidification of this naturally acid site. We initiated new paleolimnological studies using mallomonadacean chrysophytes to further our understanding of Cone Pond's recent past. Our stratigraphic analyses indicate recent striking changes in the chrysophyte flora of this lake, with Mallomonas hindonii, a species only common in recently acidified lakes, replacing M. crassisquama, a cosmopolitan species that dominated the flora over the preceding 8000 yr; this recent change parallels the declines in fish populations. Because chrysophytes often bloom in early spring and are known, in other lakes, to experience changes in community composition before those expressed by the diatom community, a possibility is that chrysophytes track t...

Distribution and character of sedimentary facies in a 196.5-m core from Ocean Drilling Program (ODP) Site 893 in Santa Barbara Basin (southern California) reflect global and regional controls during the latest Quaternary. Stratigraphic... more

Distribution and character of sedimentary facies in a 196.5-m core from Ocean Drilling Program (ODP) Site 893 in Santa Barbara Basin (southern California) reflect global and regional controls during the latest Quaternary. Stratigraphic trends in grain size, sediment composition, sedimentary fabric, and degree of bioturbation record changes in oceanic deep-water circulation, climate, sea level, basin geometry, sediment sources, and transport pathways through the last two glacial and interglacial episodes (-160 k.y.). The sedimentary sequence in Hole 893A is divided into six facies: four record varied levels of bottomwater oxygenation by the degree of bioturbation of primarily laminated olive-gray hemipelagic mud, whereas two reflect coarse-and fine-grained event deposition. Varved sediments typical of the Holocene Santa Barbara Basin compose only 21% of the entire latest Quaternary sequence. An ultra-high-resolution record (<lO-yr sample spacing) of bottom-water oxygenation, as shown by the preservation or destruction of annual varves, reveals cyclic variation over decadal to Milankovitch time scales and apparently reflects the changing age and ventilation of Pacific Intermediate Waters. Over the past-75 k.y., bioturbation and basin oxygenation correspond closely to glacial-interglacial oscillation, with warm intervals being oxygen-depleted and laminated and cold intervals being oxygenated and bioturbated. Preliminary results suggest a correlation between basin stratigraphy and deep-water circulation proxy records from elsewhere in the Pacific and Atlantic oceans, indicating that sediments of Santa Barbara Basin are a sensitive recorder of global and regional paleoceanographic and paleoclimatic change.

Definitive evidence for the onset of monsoon moisture in northern Australia following the arid phase of the Last Glacial Maximum has been elusive, in large part due to the lack of long, continuous sediment records. Here we report new... more

Definitive evidence for the onset of monsoon moisture in northern Australia following the arid phase of the Last Glacial Maximum has been elusive, in large part due to the lack of long, continuous sediment records. Here we report new evidence from two separate drainage basins in the Kimberley region of monsoonal northwestern Australia. At both sites, radiocarbon ages on (basal) biogenic materials in flood deposits indicate stream flow, as high or higher than maximum historic levels, began about 14 cal ka BP. These results suggest that the Australian summer monsoon was fully active several millennia earlier than previously expected. The early onset of the monsoon and the widespread evidence for diminished monsoon activity in the late Holocene cannot be reconciled with primary forcing of the Australian monsoon by changes in low-latitude summer insolation over Australia. r

Archaeological excavations in deep pre-mound levels at Huaca Prieta in northern Peru have yielded new evidence of late Pleistocene cultural deposits that shed insights into the early human occupation of the Pacific coast of South America.... more

Archaeological excavations in deep pre-mound levels at Huaca Prieta in northern Peru have yielded new evidence of late Pleistocene cultural deposits that shed insights into the early human occupation of the Pacific coast of South America. Radiocarbon dates place this occupation between~14,200 and 13,300 cal yr BP. The cultural evidence shares certain basic technological and subsistence traits, including maritime resources and simple flake tools, with previously discovered late Pleistocene sites along the Pacific coast of Peru and Chile. The results help to expand our knowledge of early maritime societies and human adaption to changing coastal environments.

It has been proposed that the Kosi River continuously migrated >113 km westward across the surface of the megafan over the last two centuries. Examination of a number of old maps published between 1760 and 1960 shows that during most of... more

It has been proposed that the Kosi River continuously migrated >113 km westward across the surface of the megafan over the last two centuries. Examination of a number of old maps published between 1760 and 1960 shows that during most of this period the Kosi River occupied a position slightly east of the megafan axis. The apparent channel movement shown in these maps is oscillating in nature and not unidirectional. Instead of encountering deposits left behind by a sweeping braided Kosi-like stream, a preliminary study of the uppermost 2-5 m succession in the north-central part of the megafan reveals overwhelming dominance of meandering stream deposits. Assuming the existing notion of Kosi River migration, the rate of deposition averaged over w100-200 years for the uppermost w5-10 m of megafan deposits, works out to be unusually high (>50 mm/y). All these observations question the soundness of the hypothesis of rapid westward migration of the Kosi River over the last two centuries. The existing facies model for the uppermost 8-10 m of the megafan deposits also appears untenable. The three-dimensional geometry of the Kosi megafan is similar to those of typical alluvial fans, but with much gentler gradient (0.05 -0.01 ) and with larger area (>10,000 km 2 ). Based mainly on the patterns of paleo and modern channels recognised in the satellite images, three major accretionary lobes can be identified on the Kosi megafan. Relative age of the lobes determined from the truncating relationship of the paleochannels indicates a random shift of the trunk channel forming these lobes. Similar multilobate form and evidences of random switching of the loci of lobe aggradation are also found to be common in the Tista and Taquari megafans. The factors known to favour avulsion and the results of the recent simulation studies of alluvial deposits are inconsistent with the notion of unidirectional shift of the channels for more than 100 km across the entire megafan surface. This study suggests that the relocation of the Kosi River in the past was through random nodal avulsion rather than systematic unidirectional shift. The recent avulsion of the Kosi channel by a large distance to the east follows this expected pattern. Further study and age dating is required for a comprehensive understanding of the depositional dynamics of the megafan and the pattern of channel movement on it. Future flood predictions and disaster management plans should be based on such comprehensive understanding.

Geochemical analyses as well as X ray diffraction measurements were carried out on five sediment cores from the eastern Angola Basin and the equatorial divergence of the South Atlantic. Barite concentrations were calculated from total... more

Geochemical analyses as well as X ray diffraction measurements were carried out on five sediment cores from the eastern Angola Basin and the equatorial divergence of the South Atlantic. Barite concentrations were calculated from total barium concentrations by subtracting the estimated barium background supplied by "nonbarite" barium carders. Barite concentrations assessed by this geochemical method show a good correspondence to barite concentrations determined by quantitative X ray diffraction measurements. Barite proved to be an important carrier of barium in the pelagic cores, contributing up to 90% of the total barium concentrations in the sediment, while clastic material provides an important source of barium at sites closer to the African continent. Barite accumulation rates were calculated in order to eliminate the diluting effects of varying inputs of terdgenous and biogenic material. Barite accumulation rates show cyclic variations with maxima corresponding to glacial and minima to interglacial stages. Absolute paleoproduction rates were computed from barite accumulation rates. At the Congo fan and the equatorial divergence they are consistent with calculations based on total organic carbon (TOC) accumulation. At the Walvis Ridge, glacial-interglacial cycles contrast to a constant paleoproductivity computed from TOC accumulation. GINGELE AND DAHMKE: BARIUM IN SOUTH ATLANTIC SEDIMENTS combination of geochemical and mineralogical methods. The variations in the accumulation of discrete barite particles, representing relative changes in paleoproductivity, can thus be determined for sedimentary environments with highly varying inputs of terrigenous and biogenic sediment constituents. Absolute paleoproductivity rates are computed from barium accumulation rates with algorithms defined by Dymond et al. [1992] and compared to paleoproductivity calculations of the same sites based on isotopic and geochemical methods [Schneider, 1991; Bickert, 1992]. Material, Methods, and Procedures Five gravity cores were taken during Meteor cruises M6-6 [Wefer et al., 1988] and M9-4 [Wefer et al., 1989] in the Angola Basin and the Brazil Basin and on the Walvis Ridge. Undisturbed surface samples were obtained from box cores taken at the same locations and for six additional sites at different water depths (Figure 1 and Table 1). Cores from the equatorial divergence (GeoB 1041 and GeoB 1117) and the Walvis Ridge (GeoB 1035) consisted mainly of carbonate sands and oozes with minor amounts of opal and clastic material, while the cores from the African continental margin were dominated by fine-grained, diatom-bearing terrigenous muds (Congo fan, GeoB 1008) or silty clays (Angola slope, GeoB 1023) (Figure 2). 40øW 2(YW 0 ø I I i

While caribou hunting structures are well known in the circumpolar region, equivalent features are difficult to investigate further south due to significant changes in sea level and subsequent human activity. The discovery of hunting... more

While caribou hunting structures are well known in the circumpolar region, equivalent features are difficult to investigate further south due to significant changes in sea level and subsequent human activity. The discovery of hunting structures on submerged landforms beneath modern Lake Huron provides a new window into caribou hunting in the mid-latitudes. This paper summarizes current findings and considers both the strategies for hunting caribou and the necessary organizational implications for such activities on the Alpena-Amberley Ridge. It is shown that many of the features known in the circumpolar region are also present in the mid-latitudes, but that significant differences are also observed. Many of these differences seem attributable to the seasonal migration of vast caribou herds across the causeway-like setting of the Alpena-Amberley Ridge.

Given the difficulty of separating the three Picea species—P. glauca, P. mariana, and P. rubens (white, black, and red spruce)—in the pollen record, little is known about their unique histories in eastern North America following... more

Given the difficulty of separating the three Picea species—P. glauca, P. mariana, and P. rubens (white, black, and red spruce)—in the pollen record, little is known about their unique histories in eastern North America following deglaciation. Here we report the first use of a classification tree analysis (CART) to distinguish pollen grains of these species. It was successfully applied to fossil pollen from eight sites in Maine and one in Massachusetts. We focused on the late glacial/early Holocene (14,000 to 8000 cal yr B.P.) and the late Holocene (1400 cal yr B.P. to present)—the two key periods since deglaciation when Picea has been abundant in the region. The result shows a shift from a Picea forest of P. glauca and P. mariana in the late glacial to a forest of P. rubens and P. mariana in the late Holocene. The small number of P. rubens grains identified from the late glacial/early Holocene samples…

The idea of this special issue first arose at the start-up meeting of the Baikal-Hokkaido Archaeology Project (BHAP: http://bhap. artsrn.ualberta.ca/) held in Jozankei and Sapporo, Hokkaido Prefecture, Japan, on July 15-18, 2011. The... more

The idea of this special issue first arose at the start-up meeting of the Baikal-Hokkaido Archaeology Project (BHAP: http://bhap. artsrn.ualberta.ca/) held in Jozankei and Sapporo, Hokkaido Prefecture, Japan, on July 15-18, 2011. The conference organisers gathered together a multidisciplinary team of scholars investigating Holocene hunter-gatherer cultural dynamics and environmental and climate changes in the Lake Baikal region of Russia and the Hokkaido region of Japan. The running time of the project is seven years (2011-2017). It is primarily supported by the Major Collaborative Research Initiative (MCRI) program of the Social Sciences and Humanities Research Council of Canada, with additional funding from Canada, Japan, Russia, UK and Germany. The start-up conference program consisted of twelve BHAPrelated business meetings, representing different research directions and scientific disciplines (i.e. archaeology, human osteology and DNA analyses, zooarchaeology, bone chemistry, radiocarbon dating, palaeoenvironmental field and laboratory work and numerical modelling), project management, student training, and public and academic dissemination of results. Following the notion that success of a multidisciplinary research project, such as BHAP, requires mutual understanding and collaboration, the business meetings were arranged in a series of discussions and not as parallel sessions. This gave everybody an opportunity to learn more about the methods, approaches and strategies applied by each research group, providing better knowledge of the advantages, and also the shortcomings, of the diverse proxies and data archives generated by the project, and to stimulate a productive discussion between the working groups. This strategy was indeed very successful. In particular, the archaeological component of the project was interested in obtaining as detailed as possible, and preferably quantitative, information about the Holocene environments, vegetation and climate of the study regions. Being aware that to answer these questions is one of the major aims of the project, we came to the idea of a special issue of Quaternary International to focus attention to these issues. In our understanding, such a volume would allow us, in a relatively short period of time, to accomplish four important tasks: (i) to review current palaeoenvironmental research in central and eastern Asia; (ii) to understand better the nature of environmental archives, archaeological records, and human-environment dynamics in the Baikal and Hokkaido regions; (iii) to indicate gaps in our current knowledge that are necessary to address during the running time of the project; and (iv) to develop new ideas on how these gaps can be filled.

Chl-Zr 26 and Chl-ZML relationships. This important role of ocean physics indicates that the observed Chl changes primarily reflect biomass changes due to dampened or increased nutrient fluxes to the upper lit layers. Changes in the... more

Chl-Zr 26 and Chl-ZML relationships. This important role of ocean physics indicates that the observed Chl changes primarily reflect biomass changes due to dampened or increased nutrient fluxes to the upper lit layers. Changes in the photoacclimation state of phytoplankton probably also intervene, without obscuring the global picture, however. Quantifying the respective role of both phenomena would require the parallel examination of Chl and other quantities more directly tied to biomass.

A high-resolution record was obtained by investigating a sedimentary sequence from two cores taken in the central Red Sea (R/V Meteor cruise 5, leg 2). The numerical variations between nonmigratory and migratory pteropods and their stable... more

A high-resolution record was obtained by investigating a sedimentary sequence from two cores taken in the central Red Sea (R/V Meteor cruise 5, leg 2). The numerical variations between nonmigratory and migratory pteropods and their stable isotopic record were studied together with variations in the carbonate and total organic carbon content in order to estimate changes in the structure of the water column during the last 13 kyr. The results indicate the existence of a highly stratified water column during deglaciation and early Holocene (13-8.5 ka). During this period the depth of the mixed layer varied between less than 50-100 m at most, and productivity was markedly reduced in comparison to the recent situation. The intermediate and deep water were constantly highly depleted in oxygen. A pronounced Younger Dryas event was recognized at 10.4 ka which coincides with an arid phase on the border land. The oxygenation of the intermediate water improved remarkably after 7.5 ka and peaked during the period between 4.6 and 2.0 ka. During this period the mixed layer •Geological Survey of Israel, Jerusalem, Israel. 2Institut und Museum fiir Geologic und Pal•iontologie,

We have compiled 223 sedimentary charcoal records from Australasia in order to examine the temporal and spatial variability of fire regimes during the Late Quaternary. While some of these records cover more than a full glacial cycle, here... more

We have compiled 223 sedimentary charcoal records from Australasia in order to examine the temporal and spatial variability of fire regimes during the Late Quaternary. While some of these records cover more than a full glacial cycle, here we focus on the last 70,000 years when the number of individual records in the compilation allows more robust conclusions. On orbital time scales, fire in Australasia predominantly reflects climate, with colder periods characterized by less and warmer intervals by more biomass burning. The composite record for the region also shows considerable millennial-scale variability during the last glacial interval (73.5e14.7 ka). Within the limits of the dating uncertainties of individual records, the variability shown by the composite charcoal record is more similar to the form, number and timing of DansgaardeOeschger cycles as observed in Greenland ice cores than to the variability expressed in the Antarctic ice-core record. The composite charcoal record suggests increased biomass burning in the Australasian region during Greenland Interstadials and reduced burning during Greenland Stadials. Millennial-scale variability is characteristic of the composite record of the subtropical high pressure belt during the past 21 ka, but the tropics show a somewhat simpler pattern of variability with major peaks in biomass burning around 15 ka and 8 ka. There is no distinct change in fire regime corresponding to the arrival of humans in Australia at 50 AE 10 ka and no correlation between archaeological evidence of increased human activity during the past 40 ka and the history of biomass burning. However, changes in biomass burning in the last 200 years may have been exacerbated or influenced by humans.

The article deals with the geomorphological diversity (confluence of Neris and Vilnia rivers, junction of two ice ages, erosion hill terrains, terrace levels, etc.) of Vilnius city which played an important role in choosing the place for... more

The article deals with the geomorphological diversity (confluence of Neris and Vilnia rivers, junction of two ice ages, erosion hill terrains, terrace levels, etc.) of Vilnius city which played an important role in choosing the place for the city to be established and in formation of its defence structure. The diversity of terrain of Vilnius city and its environs is demonstrated by the distinguished morphogenetic zones: 20 morphogenetic units including 5 zones within the area of the medieval city. From the point of view of the history of environment, the historical relief of Vilnius city has five types of relief. The research was carried out in one of the five types of city topography: moraines left by glaciers (part of the Kuprijoni sk _ es-Salininkai morainic complex). The shallow till acted as an impermeable barrier and created conditions for accumulation of groundwater. Springs emanated at the slope bottom turning into streams. The largest among them is the Vingr _ e River, which marks the boundary between two types of topography. The studied territory occupies 2.6 km 2. Through the reconstruction of the primordial terrain, it would be possible to trace the direction of Vingr _ e stream and the location of the defensive wall. LIDAR topography and borehole data, topographic maps of 1842 and 1994, and archaeological data were used. Geophysical and digital methods were applied. The research contributes to reconstruction of the preanthropogenic terrain, indicating possibilities for its optimal use and living conditions.

Olduvai Bed-I Small mammals Taphonomy Palaeoenvironment

The concentration rare earth elements and Yttrium (REE + Y) were determined in coral sands from Kavaratti Island, Arabian Sea, India. Chondrite-normalized REE + Y patterns show: (1) high REE concentration particularly light REE (LREE)... more

The concentration rare earth elements and Yttrium (REE + Y) were determined in coral sands from Kavaratti Island, Arabian Sea, India. Chondrite-normalized REE + Y patterns show: (1) high REE concentration particularly light REE (LREE) enrichment; (2) consistent negative Ce anomaly; (3) nearly chondritic Y/Ho ratios. All these features are consistent with the geochemistry of well oxygenated seawater with significant terrestrial contribution. The seawater composition of Nd/Yb ratio inferred from the coral record point to the dominance of LREE more than the heavy REE (HREE). The high terrestrial input rich in LREE and property of adsorption/scavenging processes of LREE than that of HREE may be the cause. Terrigenous contributions were detected on the basis of cooccurring trace element concentrations (Sc, Hf and Th) and Y/Ho ratio. Except for La, the REE distribution coefficients, KD(REE)s, are between 100 and 300. KDs are high comparing to the other elements in biogenic calcite which is attributed to detrital contamination during elemental incorporation. This study may not reflect original seawater chemistry but it can be a good proxy to indicate proximity of corals to terrigenous input sources.

To demonstrate the viability of using slug-test-analysis techniques to interpret recovery data in large-diameter, hand-dug wells, 37 wells representing a range of hydraulic conductivity and located in unconfined and weathered chalk and... more

To demonstrate the viability of using slug-test-analysis techniques to interpret recovery data in large-diameter, hand-dug wells, 37 wells representing a range of hydraulic conductivity and located in unconfined and weathered chalk and marl and confined alluvium in North-Central Texas were tested. Recovery data were analyzed by means of a numerical model, two semiempirical methods developed especially for interpreting recovery data from large-diameter hand-dug wells, and different slug-test-analysis methods that have different shape factors describing well geometry. Most hydraulic-conductivity values estimated by slug-test methods are within an order of magnitude of values that are estimated by using a numerical model or methods derived specifically for hand-dug wells. Because of the unique geometry of hand-dug wells (diameters on the same order as well lengths), care must be taken to ensure that the proper shape factors are used with slug-test methods. Because of the substantial well storage in hand-dug wells, considerable time may be required to lower the water level to the desired position, especially if pump capacity is limited. This pumping time results in a noninstantaneous withdrawal of water from the aquifer, which violates one of the assumptions of slug-test-interpretation methods. However, in low-permeability environments, reasonable results can still be attained if water removed from the well sources from well storage or if recovery time is considerably longer than pumping time.

Reconstruction of African human diet using bone collagen carbon and nitrogen isotope ratios. nature 319 (1986), 321-324. Behavioural modifications associated with the exploitation of new food resources have been linked to major steps in... more

Reconstruction of African human diet using bone collagen carbon and nitrogen isotope ratios. nature 319 (1986), 321-324. Behavioural modifications associated with the exploitation of new food resources have been linked to major steps in hominid evolution and in subsequent human cultural development1,2. Testing of specific hypotheses concerning the influence of dietary change on these processes would be facilitated by quantitative estimates of early hominid and human diets. Although most methods of obtaining such evidence provide only qualitative information2, the stable carbon and nitrogen isotope ratios of animal tissues, and in particular, bone collagen, can be used to quantify the consumption of foods having different isotopic compositions3-5. As reported here, analysis of the collagen of historic and prehistoric African human populations from Kenya, Tanzania and South Africa that have reasonably wellknown diets shows that stable carbon and nitrogen isotope ratios in bone collagen can distinguish marine foragers from populations consuming terrestrial resources, pastoralists from farmers, farmers consuming grains from those consuming nongrain crops, and camel pastoralists from capri-bovine pastoralists. suggest dietary adaptations were prime movers of hominid biological and cultural evolution.