首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 786 毫秒
1.
This study reviews the occurrence and potential of bryozoans within lithic artifacts and also sets out a methodology for their use in sourcing and discusses the advantages and disadvantages of this approach. We present case studies from our own research and from the literature on using bryozoans in sourcing archaeological lithic artifacts. Fossil bryozoans of different ages and clades can be effectively used to determine the material source of lithic artifacts from a variety of prehistoric ages. The case studies included in this report span the stratigraphic range of bryozoans from the Ordovician to the Neogene. The bryozoans came from four different orders: trepostome, fenestrate, cyclostome, and cheilostome. The use of these lithic artifacts ranged back to 25 ka. Although the majority of the fossil bryozoans were incidental in the artifacts, the bryozoans were still useful for determining their original source rock. The improved searchable online paleontologic databases allow for more efficient use of fossil bryozoans to constrain the stratigraphic and paleogeographic distribution of source outcrops. Although generally underutilized in sourcing prehistoric lithic artifacts, it is clear that by analyzing bryozoans, an increased understanding of the lithologic nature of these materials could be gained by the archaeological community.  相似文献   

2.
Over the last ninety years or so, archaeological field work on outcrops of raw materials in western France has allowed researchers to identify the use of a large number of deformed rock types in lithic industries. These materials include Armorican phtanites, which are cherts that were widely exploited during the Mesolithic, principally during its final phase (5500–5000 yrs cal. B.C.). Because of variations in the mineralogical composition and physical properties of phtanites, different mechanical properties are exhibited by samples from the four main geological formations containing this rock type in the Armorican Massif of western France. These geological and mechanical parameters influenced the quantity of rock used and the knapping methods employed. They also influenced the tool types produced and their transfer, as recorded in archaeological sequences. The types of raw materials used are also controlled by the distance to sources of coastal flint pebbles or other autochthonous siliceous rocks. Therefore, the role of raw material properties in the creation and persistence of techno‐cultural or economic characteristics is different for each type of phtanite and yields fundamental information on the interaction of society with the geological environment. © 2010 Wiley Periodicals, Inc.  相似文献   

3.
The nature and distribution of organic matter in geological cherts of archaeological use can serve to estimate the sources and origins of some remains of lithic industry. For example, organic and biomarker analysis can provide information to allow a deeper insight into source catchment areas, artefact displacement or the way in which the artefacts were employed. In this work, soluble (bitumen) and insoluble (kerogen) organic matter were isolated from several chert samples with different depositional history and analysed by means of gas chromatography–mass spectrometry (GC–MS) and spectroscopic techniques such as infrared and Raman spectroscopy. Chemometric treatment of the results allowed observation of differences between organic matter content on the basis of the depositional setting of the cherts. Samples with a continental deposition seemed to preserve more organic matter with little alteration. The hydrocarbon profiles of these samples were dominated by high molecular weight n-alkanes, alkylcyclohexanes and isoprenoid groups which allowed distinguishing them from the rest of the analysed samples.  相似文献   

4.
Accretionary desert pavements on the eastern Libyan Plateau of central Egypt support a rich Middle and Upper Paleolithic artifact assemblage exhibiting intensive blank production and minimal tool production. These assemblages appear to be in primary context with numerous examples of lithic refits showing on‐site lithic production. However, the smallest (length ≤2.5 cm) archaeological fragments are recovered at a much lower rate on this desert pavement surface than expected given comparable data from lithic assemblages in cave and shelter contexts in France. Excavation of archaeological contexts on the Libyan Plateau reveals the loss of small artifact fragments into the subsurface due to aeolian accumulation of silts, whereas geomorphic examination of desert pavement surfaces suggests a potential for relatively isolated bioturbation as a source of lateral and vertical disturbance of desert pavement surfaces over small areas. Archaeologists should be aware of the potential for long‐term assemblage stability as well as small artifact burial in surficial desert pavement contexts.  相似文献   

5.
Identifying the geological and geographical origin of lithic raw materials is critical to effectively address prehistoric forager raw material economies and mobility strategies. Currently, Paleolithic archaeology in Belgium lacks a systematic sourcing strategy to effectively substantiate detailed interpretations of prehistoric hunter‐gatherer behavioral change across time and space. This pilot study evaluates the potential to “fingerprint” flint from the Mons Basin, western Belgium, using the laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) technique and a multivariate statistical analysis of 87 geological samples and 39 Gravettian period chipped stone artifacts. We reappraise two hypotheses raised by previous scholars based on visual raw material identification: (1) the Gravettian occupants of Maisières‐Canal supplied themselves with “black flint” from one single source; (2) the sites Rhens and Koblenz‐Metternich yielded artifacts indicative of long‐distance transfer of western Belgian flint into the German Rhineland, ca. 260 km from the primary source area. Our results demonstrate the validity of LA‐ICP‐MS data with flint and compositional data analysis for fingerprinting discrete geological formations from the Mons Basin. We suggest multiple source provisioning for Maisières‐Canal. Geochemical characterization of other potential flint sources is required to validate the long‐distance transfer hypothesis of western Belgian “black flint” into the German Rhineland.  相似文献   

6.
Classification and sourcing of vulcanic lithics is simplified through petrographic and geochemical analyses. In examining volcanic lithics, major element geochemistry is required for classification, trace element geochemistry is necessary for discrimination of materials from different sources, and rare earth elements are used in source-modeling. Materials such as those found in the debitage at the British Camp shell midden, San Juan Island (45SJ24), are ubiquitous in the Gulf of Georgia region of the Pacific Northwest. Previous archaeological reports over the past 100 years have classified this volcanic debitage as basalt and predicted a local source. Petrographic analyses of thin sections and geochemical analyses using ICP emission spectrometry have shown that these artifacts are formed of dacite rather than basalt. The analysis also shows that the major lithic material used for stone chipping during the entire temporal sequence at the British Camp site is invariably from the same distant source in the High Cascades, possibly as far as 200 km from the site. © 1996 John Wiley & Sons, Inc.  相似文献   

7.
Hunter‐gatherer mobility and spheres of interaction are important characteristics worthy of investigation in Patagonian archaeology. One way to approach these is by studying the distribution of lithic archaeological materials. Siltstone (limolite) artifacts are found along the western strip of southwestern Patagonia, Argentina. Based on geomorphological studies and the high density of archaeological material, a source was located along the western margin of Cardiel Lake. Neutron activation analysis of samples from the source and archaeological sites in several neighboring basins allowed us to model its circulation. Siltstone's archaeological distribution indicates that its regional circulation had a southerly direction dating from the early Holocene. This southern vector shows an important difference when compared to the distribution of obsidian from Pampa del Asador, which has a broader circulation pattern. This could be related to a greater availability of high‐quality lithic materials north of the siltstone source. This work also contributes to the construction of a lithic source database for southern Patagonia.  相似文献   

8.
Alibates silicified dolomite is one of the principal knappable lithic materials indigenous to the Southern High Plains. Prehistorically, this material was extensively quarried along the Canadian River in Potter County, Texas. Some of these quarries are preserved in what is now the Alibates National Monument. Archaeologists working in Oklahoma traditionally interpret artifacts of Alibates silicified dolomite as evidence for long distance trade. However, a survey of three transects across the Canadian's valley in western Oklahoma reveals the persistent, but minor, presence of Alibates clasts in gravel deposits. Thirty-nine gravel exposures yielded 1365 clasts of the dolomite. The abundance, size, shape, and knappability of this material is comparable to most flakes and implements found on western Oklahoma archaeological sites, especially those of prehistoric and protohistoric Plains Villagers. © 1993 John Wiley & Sons, Inc.  相似文献   

9.
Understanding site formation processes is crucial for interpreting archaeological context patterns and hominin behaviour as these affect the preserved condition of a site and the integrity of archaeological remains. The fluvio‐lacustrine sequences in the Nihewan Basin of North China are rich sources of early Pleistocene archaeological sites, which offer an important opportunity to investigate human evolution and adapted behaviours in East Asia. Although many Palaeolithic sites have been reported from the Nihewan Basin, North China, few of them focus on site formation processes before interpreting the hominin behaviour patterns. Here, we present a site formation study of four archaeological layers (Layers 6D, 6C, 6B and 6A) in Trench 1 from the Donggutuo (namely DGT‐T1) site in the Nihewan Basin with an age of 1.1 Ma. Through the study of sedimentary contexts, spatial distributions of artefacts and fossils, intra‐assemblage category ratios, debitage size distributions, lithic abrasion, artifact orientation and planar dip, our results show that all the layers had been disturbed by low‐energy sheet wash across the lake shore setting, but to differing extents. The post‐depositional disturbance caused by water decreased from the lower to the upper layers, from Layer 6D to Layer 6A. This indicates that the archaeological remains in DGT‐T1 have not been subject to significant natural modifications and are thus suitable for studying early hominin behaviour in North China. Copyright © 2019 John Wiley & Sons, Ltd.  相似文献   

10.
This study shows how the occurrence of lithic raw-materials articulate with hunter gatherer technological organization. Three archaeological data sets representing 109 different sites and one ethnographic data set from Australia are examined to show that lithic raw-material size, shape, quality, and availability play a major role in hunter gatherer decisions to make various kinds of stone tools. These characteristics of lithic material occurrence are used to help explain why expedient technologies such as bipolar tool production are sometimes used, and why formalized technologies such as bifacial production may be selected as a tool production strategy. Stone tool morphological variability and technological variability are shown to be directly related to the geological occurrence of stone tool raw materials. © 1994 John Wiley & Sons, Inc.  相似文献   

11.
The use of mineral magnetic techniques as pollution proxy for road deposited sediment was explored using various statistical approaches. Standard techniques were adopted for measurement of mineral magnetic and geochemical parameters. The analyses of magnetic parameters revealed that the samples were dominated by ferrimagnetic minerals and multidomain grains. This implied that the magnetic fractions in the samples might be of anthropogenic origin. Results also indicate that the samples were dominated by low coercive, magnetically soft minerals. Thermomagnetic curves confirmed magnetite as the remanence bearing magnetic mineral having a Curie point temperature of ~580 °C. The strong association observed between magnetic susceptibility, susceptibility of anhysteric remanent magnetization and saturation isothermal remanent magnetization and aluminum, titanium, manganese, iron, chromium and lead demonstrated that these metals occurred as ferrimagnetic particles of technogenic origin resulting from vehicular sources. Assessment of pollution status of the road deposited sediment identified silicon and lead as the priority pollutants of concern. Generally, pollution load index was <1 (mean, 0.66 ± 0.14), indicating that the samples were not polluted in the overall, but the metals were in the buildup stage requiring constant monitoring. The sources of pollutants from principal component and cluster analyses identified the sources of pollution to be mainly from vehicular emissions such as brake linings, exhaust materials, tire wear, corroded metal parts, abrasion of lubricating oil and road construction materials. This study found that mineral magnetic techniques offer great potential as pollution proxy for soil pollution studies.  相似文献   

12.
A lithological and mineral magnetic study of three soil and underlying sedimentary sections located at different topographic positions in the Undulating Pampa was performed. On the basis of grain size analyses, clay, silt and sand mineralogy, and total Ti/Zr relationship three different sedimentary units were recognised in the profiles under study suggesting that the area has been influenced by three different sources of sediments. Magnetic susceptibility (MS) appears to be related to lithology, allowing the identification of some material and lithologic discontinuities. In the studied cases the maximum values of MS appear in both the B horizons of the present zonal soils as well as in the primary or reworked loess levels. In contrast, minimum values are associated with calcrete, paleosol, and hydromorphic horizons. Although magnetic susceptibility appears to be an effective means for identifying different materials and pedological features in this area, due to the superposition of effects on the magnetic signal a thorough interpretation of MS requires that a composite analysis should be made.  相似文献   

13.
柴达木盆地东北部3500年树轮定年年表的初步建立*   总被引：3，自引：9，他引：3       下载免费PDF全文
利用柴达木盆地东北部山地上生长的活树,尚未倒伏的死树和山前洪积扇上古墓中保存的椁木、棺木和封土柏木,在树轮年代学交叉定年技术的支持下,建立了该区长达3500年的树轮定年年表。最长的活树样本可追溯到公元404年,古木样本覆盖的时段是公元前1580年~公元793年,而死树样本覆盖了公元130~1794年。3种样本在时间上具有很长的重叠时段,为建立长定年年表提供了可行。样本间能够很好地交叉定年。此外,古木和死树在重叠时段轮宽变化的相关系数是0.51,死树和活树的是0.41,并且古木和活树的是0.61。这种极显著的相关关系说明建立长定年年表是可能的。将程序COFECHA为每个活树样点保存的定年序列、古木的定年序列和死树的定年序列放在一起,再运行程序COFECHA,就建立了一个基于621棵树的样本量组成的总定年年表。该年表的取材完全独立于已发表的都兰年表,在时间上比都兰年表向前延伸了近1000年,使其能够达到商、周朝代。与调整后的都兰年表对比,发现两者在公元前328年~公元2000年之间完全能够交叉定年。文章所建的树轮定年年表是国内目前最长的连续年表,它可为我国西北干旱-半干旱区树轮长序列的定年提供标尺。  相似文献   

14.
根据产状和成因,本文将西秦岭中志留统含铀岩系中的硅质岩分为,(1) 成岩过程中硅化交代碳酸盐岩所形成的硅质岩,产于碳酸盐岩和泥质岩类所组成的透镜层的顶部或碳酸盐岩层内;(2) 早期成岩阶段形成的纹层状硅质岩,主要产于碳酸盐岩和泥质岩透镜层底部或呈薄层夹于粉砂岩、泥质岩层中。根据沉积环境分析及硅质岩的化学成分、REE分布模式和氧同位素组成,提出本区硅质岩形成于受大气淡水影响的局限浅海环境。  相似文献   

15.
This study covers cosmic spherules derived from the Mesoproterozoic Dahongyu Formation in the Ming Tombs area, Beijing. The cosmic spherules include iron oxide cosmic spherules, carbonaceous chondrites, and atomic iron “steely bead”-shaped cosmic spherules. The mineral assemblage of silicon carbide, forsterite, zircon, and glass spherules and fragments were picked from melt-silicified carbonate of the Mesoproterozoic Dahongyu Formation (ca. 1625 Ma). Cosmic spherule assemblages are solely discovered from sedimentary rocks in China. Platinum group elements (PGE) were determined for the first time in cosmic spherules and associated minerals. PGE comparative observation between meteorite and cosmic spherules is presented in this study. It is recognized that an extraterrestrial meteorite impact event might have occurred in the Dahongyu Stage. The main evidence is a large number of iron cosmic spherules in silicified oncolitic limestone, and associated cosmic silicon carbide, glass spherules, and fragments, as well as the presence of forsterite. The impact-volcanic crater is characteristic of a big black shale block dropped into the bended silicified limestone.  相似文献   

16.
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.  相似文献   

17.
Serena Love 《Geoarchaeology》2012,27(2):140-156
This article provides a methodology for extracting social information through an analysis of mudbrick compositions, using a case study from Çatalhöyük, Turkey. Particle size analysis, loss on ignition, and magnetic susceptibility were used to examine variability in mudbrick recipe. The analysis revealed that neither magnetic susceptibility nor calcium carbonate were significantly altered through tempering. The results suggest that the greatest degree of compositional variability was a result of the manufacture process and not raw materials used in production. Mudbricks are products of deliberate human actions, similar to any other artifact assemblage, but have been long overlooked. Examining the technology involved with mudbrick manufacture highlights aspects of Neolithic social life through shared resources, production choices, and organization of labor. The analysis of mudbrick compositions considers how raw materials were used within and between groups of houses, represented in 1000 years of uninterrupted occupation at Çatalhöyük.  相似文献   

18.
This paper documents the results of nondestructive X‐ray fluorescence (XRF) geochemical analyses and comparisons of silicified rhyolites from the Black Canyon and Sedillo Hill prehistoric quarries near Socorro, New Mexico, and subsequent comparisons of the quarry rhyolites with 11 temporally diagnostic projectile points. At the current level of analysis, findings indicate that (1) the two quarries are chemically distinct and (2) the lithic materials of two projectile points match the silicified rhyolite from the Black Canyon quarry, suggesting quarry use during the Early Archaic period (4800–3200 B.C.) and the Late Archaic period (1800–800 B.C.). A close match between the Black Canyon rhyolite and one other point provides tentative support for use of the quarry during the Clovis Paleoindian period (9500–9000 B.C.). Additional geochemical analyses of the two quarries and other regional sources should be undertaken to verify these results and further expand our understanding of prehistoric mobility in the Southwest. © 2004 Wiley Periodicals, Inc.  相似文献   

19.
We introduce the use of Nd isotopes as a high‐precision technique that can be used in conjunction with visual, petrographic, and trace element analyses to source indistinct felsitic debitage. This approach allows sourcing of debitage from southeastern New England, including samples that previously could not be constrained to one source. Combined with trace element data, isotopic data also provide the possibility of sourcing debitage to a particular quarry site within a volcanic complex, and even to a particular ash flow within a quarry site. Determining the origin of debitage so precisely is important for understanding acquisition, trade, and exchange networks in southeastern New England, where distances separating quarry sites within an individual volcanic complex (Lynn–Mattapan) are greater than distances between different volcanic complexes (Lynn–Mattapan, Blue Hill, and Wamsutta). The sourcing of debitage to Mattapan quarries suggests that Middle Archaic populations in the northwest part of the Boston Basin obtained nonlocal lithic material primarily from sources south of the basin. © 2000 John Wiley & Sons, Inc.  相似文献   

20.
The anisotropy of magnetic susceptibility (AMS), hysteresis and thermomagnetic curves of two sets of obsidians with contrasting bulk compositions are reported in this work. The cooling and deformation history of one of those obsidians is perfectly known, as these specimens were produced in the laboratory using material from a basaltic lava flow. The other samples are occurrences of a more silicic composition and for which the AMS has been documented to have a close relationship with the distribution of microlites. The results of our measurements indicate that although the deformation and cooling histories of the lava might influence the exact composition of the ferromagnetic fraction, the relationship between the AMS and the deformation history does not seem to be altered. Furthermore, the results of this work indicate that the AMS can be associated to a population of ferromagnetic minerals of a submicroscopic size, despite of which it can be very well defined and yield large degrees of anisotropy. It is suggested that the AMS associated to such population of small grains might indeed be the origin of the AMS of other igneous rocks that have an optically observable fraction of mineral grains, although until present it had been overlooked in most instances. Use of tests designed to identify the contribution of a superparamagnetic fraction (SP) in the magnetic properties of a rock can help us to identify the presence of such a SP-related AMS in other cases.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号