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1.
One of the basic problems in the prehistoric studies of the Trieste Karst (northeastern Italy) is that of understanding the use of the numerous caves, which represent the only sites known from Palaeolithic to Middle Bronze Age. Recent sedimentological and soil micromorphological analyses add new data to the traditional archaeological ones. In our opinion, the data should be approached from other than an exclusively chronotypological point of view. The inferences of the data indicate that certain areas of four caves were used for stabling animals, and that this model of site use may be extended to most of the Karst cave sites for the period from the Neolithic to Early Bronze Age. © 2000 John Wiley & Sons, Inc. 相似文献
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Sur‐les‐Creux rockshelter is located in the Prealps of southwestern Switzerland. The sequence of deposits in the rockshelter is 80 cm thick and consists of weathered gravels in a phosphate‐rich matrix. A few Middle Palaeolithic artifacts and the bones of cave bear (Ursus spelaeus) were recorded in the fill. We present the results of sedimentological, geochemical, and micromorphological analyses of the rockshelter sediment. All analyses suggest an endokarstic origin of the sediments. The alteration cortices of the gravels imply in situ weathering over a long period. The phosphates are essentially biogenic and have an apatitelike nature. Phosphatization and intense mixing of the sediment are attributed to cave bear (digging of lairs, input of excrements, and carcasses). Only rare carnivore coprolites (lynx) were preserved in the cave deposits. © 2004 Wiley Periodicals, Inc. 相似文献
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在人类发展过程中,石灰岩洞穴往往为古人类提供了居住条件。在我国北方和南方许多石灰岩溶洞内,不仅发现大量的哺乳类化石,并且有些成为重要的文化遗址,如著名的北京周口店第一地点洞穴的北京猿人遗址等。在地层上,一些洞穴在山区可以成为易存第四纪堆积物的场所,厚度可以达到数十米;甚至数米厚的堆积层中也能记录着第四纪古环境的重要变化。 相似文献
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The pedogenic histories of four adjacent profiles of a polygenetic palaeosol developed on a Middle Pleistocene terrace of the proto-Thames from Wivenhoe in southeast England are reconstructed on the basis of superposition of key micromorphological features. Despite a considerable variation in macromorphology, partly resulting from large-scale periglacial features, three of the profiles have similar micromorphological records in that they retain evidence for two phases of clay illuviation separated by a period of periglacial disruption. This reconstruction, however, seems to be incomplete because the fourth profile contains micromorphological evidence for a further illuviation–disruption cycle. The extent of this variation suggests that soil micromorphology should be used only with care to reconstruct pedogenic or pedosedimentary histories of complex polygenetic palaeosols, or to compare such palaeosols on different surfaces of chronosequences spanning periods of major climatic change. The variable and possibly limited resolution of micromorphology, together with the current uncertainty over the exact environmental signifiance of illuvial clay features, means that inferred pedogenic phases should be correlated with specific climatic stages only with considerable caution. © 1998 John Wiley & Sons, Ltd. 相似文献
5.
A major environmental and societal event struck the Mediterranean basin during the 9th millennium cal BP. A sudden and major climatic crisis occurred in the Northern Hemisphere around 8200 cal BP leading to hyper arid conditions along a tropical zone between 15° and 40° North (Near and Middle East), cooler and wetter conditions in western and central Europe, and marked climatic irregularity in the northern Mediterranean basin. At the same time, frequent cultural gaps are observed in cave infillings from Greece to the Spanish peninsula between 8500 and 8000 cal BP, making the vision of the European Mesolithic–Neolithic transition more complex. Furthermore, a stratigraphic and socio-economic rupture associated with a spatial redistribution of sites characterizes the PPNB-NC/Yarmoukian transition in the Near East. The impact of these climatic and environmental changes in the first centuries of the neolithisation of Mediterranean Europe is discussed, using the socio-cultural, economic, stratigraphic and chronological evidence for the first farmers and last hunter-gatherers. This evidence is compared to recent paleoclimatic and geo-archaeological data obtained from prehistoric contexts, in order to measure the hydro-morphological impact on activities in valleys and karstic rockshelters. 相似文献
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Radiocarbon sequences from some northern Mediterranean cave sites show a temporal gap between Mesolithic and Neolithic occupations. Some authors regard this as a regional phenomenon and have sought to explain it in terms of a general population decline in the late Mesolithic, which facilitated the replacement of indigenous foragers by immigrant farmers. New evidence from the rockshelter site of Mala Triglavca, in Slovenia, leads us to question this view. We describe the deposits in the rockshelter and discuss the results of AMS radiocarbon dating of bone samples recovered in excavations in the 1980s. New archaeological investigations and associated soil/sediment analyses show that in the central part of the rockshelter a well‐defined stratigraphic sequence can be established, despite post‐depositional modification by soil forming processes. There is also evidence of substantial post‐depositional disturbance of the cave sediments by human agency and geomorphological processes, which have created “temporal gaps” and “inversions” in the radiocarbon sequence. The relatively large series of radiocarbon dates obtained enables some of the post‐depositional processes to be identified. © 2008 Wiley Periodicals, Inc. 相似文献
9.
Andrea Zerboni 《Geoarchaeology》2011,26(3):365-391
In the Khartoum region of central Sudan, Mesolithic sites were established on sandy ridges distributed along the Nile. Most of the excavations carried out in recent decades have revealed limited preserved archaeological structures or layers corresponding to subsequent phases of human presence due to the disturbance of the deposits. Post‐depositional processes affecting Mesolithic sites include (1) the excavation of Neolithic to Post‐Meroitic cemeteries at the same sites, (2) surface erosion, and (3) pedoturbation leading to the mixing of the stratigraphy. During a recent field operation along the western bank of the White Nile, archaeological contexts that were only partially disturbed were identified. Employing a geoarchaeological approach and the micromorphological study of sediments (supported by 14C dating), settlements were placed in their paleoenvironmental contexts and differences between in situ Mesolithic layers and those disturbed by later processes were identified. Furthermore, it was possible to interpret the functional aspects of three categories of pits containing Mesolithic pottery (fireplace pits, fireplace pits with shell accumulations, and waste pits) and to discuss their significance within the wider framework of North African archaeology. Finally, this project has demonstrated the importance of integrating the geosciences (especially micromorphology) and archaeology in the study of processes leading to the formation and preservation of open‐air prehistoric sites in arid landscapes. © 2011 Wiley Periodicals, Inc. 相似文献
10.
Irini Sifogeorgaki Hans Huisman Panagiotis Karkanas Viola C. Schmid Gerrit L. Dusseldorp 《Geoarchaeology》2024,39(3):212-237
Umhlatuzana rockshelter is known for its continuous record of Middle and Later Stone Age lithic assemblages. This study presents multiproxy geoarchaeological data (micromorphology, X-ray diffraction and scanning electron microscopy with energy-dispersive spectroscopy) to reconstruct the depositional and post-depositional history of the site. Although the Stone Age deposits macroscopically appear homogeneous, micromorphological analysis reveals the existence of primary, unaltered depositional microlayering throughout the sequence. Sediments related to combustion activities on-site are observed in both the Holocene and Pleistocene deposits. Post-depositional geochemical alterations result in the formation of several phosphatic minerals that significantly affect the site's preservation conditions. One of those is vashegyite, a rare magnesium phosphate mineral related to acidic and moist sedimentary environments. Bioturbation features are prominent at the microscale, but sediment mixing does not seem to affect the vertical distribution of the artifacts. The observation of horizontal microlayering in both the Pleistocene and Holocene illuminates the dominant mechanism of sedimentation throughout the site's 70,000-year occupational history. It moreover shows that the lithics can be analysed as coherent assemblages. 相似文献
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The Shurmai rockshelter (GnJm1) is located in the semiarid Mukogodo Hills region of north central Kenya. The rockshelter cavity is formed in Precambrian granite gneiss. The site contains a stratified sequence of sediments and archaeological materials that date from the end of the African Middle Stone Age (at or before ca. 45,000 yr B.P.) to modern times. The stratigraphic sequence at the Shurmai rockshelter is described and the principal noncultural formation processes responsible for its creation are reconstructed. Extant rockshelter sediments consist predominately of coarse angular rubble produced by rock fall, and additional sands and gravels produced by granular disintegration, slopewash, debris flow activity, and, to a lesser extent, human activity. The more identifiable aspects of the geologic history of the shelter include a number of episodes of rock fall deposition, in situ rock fall weathering, and erosional truncation. The reconstruction of the formation processes active at the Shurmai Rockshelter is used to illustrate how such geoarchaeological analysis clarifies understanding of prehistoric human occupation in rockshelter contexts in general, and in granitic terrane in particular. © 1999 John Wiley & Sons, Inc. 相似文献
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贵州荔波董哥洞3号石笋的同位素年龄及古气候信息 总被引：12，自引：2，他引：12
石笋是岩溶记录中最全面、最系统的古气候环境信息库,研究表明,洞穴内、外环境变化,都不同程度地显示在石笋的组成、结构构造、沉积 (生长 )纹层及其层面构造、沉积速率和古气候环境变化等方面。利用洞穴石笋保存的信息重建古环境,是近 2 0年来的热门课题之一。当前全球气候变化预测研究中,洞穴石笋的高分辨率定年和碳、氧同位素组成的变化规律,为这个领域的突破和填补空白作出了重大贡献。本文通过对荔波董哥洞 3号石笋进行热电离质谱 (TIMS)U-系测年及碳氧同位素分析,获得了距今 16.33万年至 9.13万年的古气候信息。石笋在大于 16.33万年前开始生长,9.13万年后停止生长,平均沉积速率为 2.87mm/ 100a(未扣出间断时间 ),属中更新世的产物。其年龄与δ18O的变化可与深海岩芯V2 8～ 2 38同位素记录所揭示的第五和第六阶段以及与北方离石黄土层 (L2 )和下马兰黄土第一古土壤层 (S1)进行对比。它反映此阶段区内经历了寒冷和温暖 (间夹冷期 )等气候变化,与全球古气候变化波动基本一致,同时也存在地区性的气候变化。 相似文献
13.
Speleogenesis of Selected Caves beneath the Lunan Shilin and Caves of Fenglin Karst in Qiubei, Yunnan 总被引：2，自引：1，他引：1
Yunnan is famous for its attractive karst landscapes especially shilins, fengcong and fenglin. The development of caves beneath the shilins in the vicinity of Lunan is closely connected with the formation of shilins. Most of the waters percolating through shilins run through the caves beneath them and are responsible for their formation. The study of cave speleogenesis deepens knowledge about both the development of shilins and karst structure. In the vicinity of the Lunan Shilin, speleological, morphological and structural geological studies of four karst caves have been accomplished. At Puzhehei, Qiubei, which is characterised by numerous fenglin, fengcong and caves, speleological and morphological studies have been performed. Cave sediments for paleomagnetic analyses have been taken from all studied areas (samples CH 1-9). Karst caves in SE Yunnan are probably much older than the age of the cave sediments (<780,000 years B.P.). The studied areas are located in the vicinity of the Xiaojiang fault (N-S 相似文献
14.
Soil‐geomorphic analysis coupled with micromorphology, SEM/EDS, magnetic susceptibility, and conventional sedimentological studies allowed us to reconstruct the site formation history and validate the archaeologically observed variability of human activities in the prehistoric camp of Ohalo II (19.5 ka B.P.), Sea of Galilee, Israel. The cultural layers rest upon the Late Pleistocene Lake Lisan deposits that accumulated under conditions of changing water supply and increasing rate of sedimentation from deep‐water varvelike deposits to basalt‐derived, near‐shore sandy lacustrine deposits. Intermittent occupation is recorded in some localities, indicating short‐term inundation episodes, which led to partial truncation and deformation of the sediments, primarily in the eastern lakeward part of the site. On the elevated, landward positions, incipient soils with strongly bioturbated profiles formed. Micromorphology demonstrates that intentional flooring was applied within the remains of brush huts, where millimeter‐sized, horizontally organized burnt and unheated vegetal tissues were likely to have been placed upon the compacted ground. In fireplaces, the cultural deposits in thin sections are composed of strongly mixed, abundant wood charcoal, ashes, and fishbone remains. Post‐depositional alterations were controlled by intermittent inundation of the site and salinization, which induced gypsum and pyrite deposition, primarily along decayed roots, and eventual pyrite oxidation. Accumulation of sodium and chlorine in the post‐occupation deposits is likely to have occurred because of discharge of saline groundwater. Although only suggestive at this stage of research, the conclusions drawn from magnetic susceptibility parameters of archaeologically related deposits at Ohalo II fit well with the micromorphological reconstructions and provide new information on the Late Pleistocene evolution of the Lake Lisan/Sea of Galilee fluctuating system. © 2003 Wiley Periodicals, Inc. 相似文献
15.
神农宫和祥龙洞洞温季节变化特征及其对石笋氧同位素组成的可能影响 总被引：2，自引：1，他引：1
通过对江西万年县神农宫和陕西宁强县祥龙洞两个洞穴内、外温度连续19个月的同步监测以了解不同时间尺度下洞穴温度变化特征。结果显示神农宫及祥龙洞洞内温度存在明显的季节性变化:（1）神农宫夏秋季洞内温度在小时-日尺度上受到降水事件的影响显著,洞内夏秋季温度波动明显高于冬春季。祥龙洞监测点所处支洞环境相对封闭,温度波动在冬春季大于夏秋季,且全年洞温变幅小于神农宫。（2）旬—季节尺度的洞温数据显示,一个完整水文年内,神农宫两个监测点SN1、SN2的温度变幅分别达到4.8 ℃和4.6 ℃,祥龙洞达到3.2 ℃。（3）两个洞穴洞内温度响应洞外气温的变化都存在滞后性,且冬春季滞后大于夏秋季,可能受深部围岩温度相对偏高、空气和围岩热导率的季节变化以及降水季节差异的影响。最后,针对洞温存在较大季节变化的洞穴讨论了不同沉积模式下洞穴温度变化对石笋氧同位素组成18O的可能影响。认为此类洞穴某一时期石笋δ18O出现较大幅度偏正或偏负不一定反映了外界气候的大幅变化,也可能仅仅是由于洞穴沉积条件发生改变而造成的。 相似文献
16.
In this study the sedimentology, micromorphology and structure of four deformation es in end moraines or near-end moraine settings are presented. Micromorphology has proven be a powerful tool in the interpretation of the sediments. The four sites are related to three of the four major glaciations known from this part of Patagonia: Nahuel Huapi, Anfiteatro and Pichileufú. All four sites are characterised by glaciolacustrine vironments in which sedimentation occurred at least partly on and/or against dead ice. With the exception of one section in the San Martin de los Andes area, where deformation occurred active ice-push, all major disturbances (faults and folds) are the result of dead ice collapse. Comparison with micromorphological observations on basal tills shows that the sediments all lack clear subglacial imprint. 相似文献
17.
Evaporitic‐lagoonal marl and dolomite laminar fill sediments are preserved in relict dry caves of the Dead Sea Fault Escarpment (Israel) which has been tectonically active since the Late Neogene. The hosting caves are located within Turonian massive carbonate bedrock and at higher altitudes than previously documented fill sediments of the Dead Sea depression. Based on the relative altitudes of the cave sediments, the ‘reversed stratigraphy’ of the Dead Sea depression fill sediments, possible partial correlation of the cave sediments with other fill sedimentary units of the depression, and sedimentary, geochemical and mineralogical characteristics, it is concluded that: (i) the cave sediments are among the oldest of the depression fill; and (ii) the deposition of the cave sediments took place in hypersaline dolomite‐precipitating water bodies of Late Neogene age, during the initial morphotectonic stages of the depression formation. Variable and relatively low Sr/Ca and δ34S ratios of the cave sediments (assuming precipitation from sea water) suggest variable fresh water input into the depositional brine. The present altitudes of the cave sediments reflect Late Neogene levels of water bodies in the depression, modified by vertical post‐Late Neogene tectonic movements within the still active fault escarpment. According to these altitudes, a 50 to 250 m uplift of the western margins of the depression since the Late Miocene to Early Pliocene is inferred. 相似文献
18.
Joseph Schuldenrein 《Geoarchaeology》1998,13(5):501-526
Archeological excavations in a karstic cavern on the south facing slopes of the Pindus range, southern Albania, have disclosed a continuous, 4.5 m thick sequence of human occupation since the Mesolithic. In 1994 geoarcheological field work identified nine (9) principal lithostrata that correspond with successive occupations. Sedimentary sequences indicate that during the Mesolithic spring flow was active and produced a pool in the cave's central chamber. This accounts for settlement along the dry western margin of the cave. After 6000 B.P. episodic flushing of Terra Rossa soil from the cave slopes was dominant. Sediments were variously modified or mobilized by weathering, diagenesis and human agency. These changes are correlated to the chronology and contribute to a limited reconstruction of site formation process. Comparison of sediment stratigraphy with an earlier study of magnetostratigraphy verifies an inferred moist pulse of the Early Holocene/Mesolithic and a turn to warmer/drier conditions during the Middle Holocene/Neolithic. The Konispol sequence is compared to cave chronologies in neighboring Epirus (Kastritsa and Klithi) and to Franchthi in southern Greece. Sedimentation patterns reveal that these caves were initially occupied at the same time (Late Pleniglacial) and that during deglaciation there was a general hiatus in deposition (15,000–10,000 B.P.). Early Holocene moisture phases correspond to an increase in sedimentation during the Neolithic when the caves were intensely utilized. © 1998 John Wiley & Sons, Inc. 相似文献
19.
根据遥感影像信息特征和盐湖气候变化模型，结合盐湖沉积特征和现代盐湖演化理论，通过对环状影像的成因进行解译和分析，将环状影像反映的1000年来盐湖气候变化的信息与北半球同期气候变化曲线对比，认为罗布泊盐湖是现代沉积形成的，是现代盐湖向干盐湖的演化历程中，由于气候冷暖交替变化而使盐湖沉积发生规律性变化的结果。 相似文献
20.
Helen Lewis 《Geoarchaeology》2007,22(7):685-708
Preliminary soil micromorphology study of cultural sediments at Tabon Cave, Philippines, supports interpretations of sporadic occupation in the Paleolithic. The presence in some deposits of authigenic minerals potentially related to altered cultural materials, such as ash, needs further investigation. Later in the sequence there is a marked change in local depositional processes, with the onset of significant quartz sand deposition in layers dating from the Middle to Late Holocene. This could relate to beach development in the area. Future sedimentological study and dating would confirm this interpretation, which suggests that in appropriate settings, stratified cave sediments could be useful for the study of regional sea level rise. © 2007 Wiley Periodicals, Inc. 相似文献