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21.
Investigations at the Carson site (22CO505), located in Coahoma County, Mississippi, have uncovered data on the development of a large Mississippian mound center dating to the period from A.D. 1200 through European contact. Recent sediment coring, excavation, artifact analyses, and radiocarbon and optically stimulated luminescence (OSL) dating shed light on earthworks and household structures at Carson, and on Mississippian culture in the Yazoo Basin more generally. Sediment coring demonstrates a laterally transgressing Mississippi River system deposited coarse sandy ridges and clay-filled swales underneath a surface horizon comprised of variously coarse to medium-fine sediment originating from generalized overbank flooding. In some instances, flood-borne sediments were found on mound flanks, indicating that at times river-based flooding may have interrupted mound construction. Sediment coring and trench excavation also demonstrate that Carson’s Mound D was built in four stages, with Stages II and III comprising the major stages of earth moving. Excavations on the mound summit reveal evidence of several superimposed structures that were burned in place and likely used for the production of stone, shell, and wooden craft items, perhaps related to Mississippi Ideational Interaction Sphere (MIIS) paraphernalia. Here we describe recent investigations at Carson and present preliminary findings; forthcoming publications will emphasize strategies of power, monumentality, craft production, and Mississippian exchange systems.  相似文献   
22.
The aim of this paper is to investigate whether the ceramics from the Goguryeo fortified sites of the Han River region in central Korea were manufactured and consumed locally during the southern expansion of the Goguryeo State (475–551 ce ). For this research, 88 ceramic samples from seven contemporary sites in the southern territories of Goguryeo were sampled and analysed by ceramic thin‐section petrography and neutron activation analysis (NAA). In addition, to establish a possible chemical fingerprint at Hongryeonbong Fort 2, five clay specimens were also gathered and analysed from the pottery firing structure. The results of this analytical study indicate that the majority of the ceramics from the Goguryeo fortified sites of central Korea were produced and circulated within this newly acquired region. In addition, it is highly probable that Hongryeonbong Fort, which contains the remains of what may be ceramic firing architecture, is the place of production for the ceramics.  相似文献   
23.
This article explores the levels of fragmentation and fracture patterns in archaeofaunal assemblages from the lower basin of the Colorado River (Argentina) following Outram's methodology. Remains of ungulates (guanaco) have suffered, in these assemblages, a high degree of fragmentation probably caused during the processing of the carcasses. The presence of helical debris and shaft fragments indicates that fragmentation would respond to processing tasks for the consumption of marrow and possibly bone grease. The results of the application of this methodology that were obtained from the analysis of three late Holocene sites (La Primavera, Loma Ruiz 1 and El Tigre) are presented. These results provide new evidence not only for patterns of marrow and bone grease consumption but also for dealing with the subsistence model proposed for the study area. In this sense, the intensification processes already proposed during the final late Holocene (1000–250 bp ) are discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
24.
From AD 1274 Chinese emperor Kublai Khan dispatched fleets of ships in a series of attempts to expand the empire's hegemony and extend his rule into East Asia (Japan) and Southeast Asia (Vietnam, Champa and Java). Archaeological remains associated with the fleets and battles have been found at Takashima Island, Japan and on the B?ch Ð?ng River, Vietnam. This paper develops a thematic approach to these sites within a framework of naval battlefield archaeology. It compares the similarities and differences in environmental conditions and archaeological contexts of the two sites in Japan and Vietnam. It also outlines recent archaeological research conducted between 2008 and 2010 on the physical remains at the B?ch Ð?ng River battlefield site.  相似文献   
25.
The aim of this study was to present classic bone lesions caused by tuberculosis, as seen in a Late Neolithic–Early Copper Age osteoarchaeological sample deriving from the site of Alsónyék‐Bátaszék (the western part of Hungary from the 5th millennium bc ). In one particular case of an adult male skeleton, vertebral bodies' destruction, collapse, ankylosis and marked angulation in the lower thoracic and the upper lumbal region of the vertebral column were observed. The collapse resulted in a severe gibbus formation. The paleopathological analysis was carried out using morphological observation supported by radiological analyses. The results from this study increase our knowledge of the early occurrence of skeletal tuberculosis in past populations. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
26.
Structure‐ and tectonic‐related gas migration into Ordovician sandstone reservoirs and its impact on diagenesis history were reconstructed in two gas fields in the Sbaa Basin, in SW Algeria. This was accomplished by petrographical observations, fluid inclusion microthermometry and stable isotope geochemistry on quartz, dickite and carbonate cements and veins. Two successive phases of quartz cementation (CQ1 and CQ2) occurred in the reservoirs. Two phase aqueous inclusions show an increase in temperatures and salinities from the first CQ1 diagenetic phase toward CQ2 in both fields. Microthermometric data on gas inclusions in quartz veins reveal the presence of an average of 92 ± 5 mole% of CH4 considering a CH4‐CO2 system, which is similar to the present‐day gas composition in the reservoirs. The presence of primary methane inclusions in early quartz overgrowths and in quartz and calcite veins suggests that hydrocarbon migration into the reservoir occurred synchronically with early quartz cementation in the sandstones located near the contact with the Silurian gas source rock at 100–140°C during the Late Carboniferous period and the late Hercynian episode fracturing at temperatures between 117 and 185°C, which increased in the NW‐direction of the basin. During the fracture filling, three main types of fluids were identified with different salinities and formation temperatures. A supplementary phase of higher fluid temperature (up to 226°C) recorded in late quartz, and calcite veins is related to a Jurassic thermal event. The occurrence of dickite cements close to the Silurian base near the main fault areas in both fields is mainly correlated with the sandstones where the early gas was charged. It implies that dickite precipitation is related to acidic influx. Late carbonate cements and veins (calcite – siderite – ankerite and strontianite) occurred at the same depths resulting from the same groundwater precipitation. The absence of methane inclusions in calcite cements result from methane flushing by saline waters.  相似文献   
27.
F. H. Weinlich 《Geofluids》2014,14(2):143-159
The ascent of magmatic carbon dioxide in the western Eger (Oh?e) Rift is interlinked with the fault systems of the Variscian basement. In the Cheb Basin, the minimum CO2 flux is about 160 m3 h?1, with a diminishing trend towards the north and ceasing in the main epicentral area of the Northwest Bohemian swarm earthquakes. The ascending CO2 forms Ca‐Mg‐HCO3 type waters by leaching of cations from the fault planes and creates clay minerals, such as kaolinite, as alteration products on affected fault planes. These mineral reactions result in fault weakness and in hydraulically interconnected fault network. This leads to a decrease in the friction coefficient of the Coulomb failure stress (CFS) and to fault creep as stress build‐up cannot occur in the weak segments. At the transition zone in the north of the Cheb Basin, between areas of weak, fluid conductive faults and areas of locked faults with frictional strength, fluid pressure can increase resulting in stress build‐up. This can trigger strike‐slip swarm earthquakes. Fault creep or movements in weak segments may support a stress build‐up in the transition area by transmitting fluid pressure pulses. Additionally to fluid‐driven triggering models, it is important to consider that fluids ascending along faults are CO2‐supersaturated thus intensifying the effect of fluid flow. The enforced flow of CO2‐supersaturated fluids in the transitional zone from high to low permeability segments through narrowings triggers gas exsolution and may generate pressure fluctuations. Phase separation starts according to the phase behaviour of CO2‐H2O systems in the seismically active depths of NW Bohemia and may explain the vertical distribution of the seismicity. Changes in the size of the fluid transport channels in the fault systems caused, or superimposed, by fault movements, can produce fluid pressure increases or pulses, which are the precondition for triggering fluid‐induced swarm earthquakes.  相似文献   
28.
29.
Several researchers have suggested use of watercraft during the Early Paleoindian period 11,500 and 10,800 rcybp (13,400–12,700 cal B.P.), but none have brought empirical data to bear on this possibility. This paper addresses the potential for fluted point-making groups to have made and used boats circa 11,000 rcybp (13,000–12,800 cal B.P.). Fluted point data from a large region of the upper and central Mississippi River valley strongly suggest that the Mississippi River was a barrier to movement and that Early Paleoindians in the midcontinent did not routinely use watercraft.  相似文献   
30.
位于长江入海口的“长江口二号”清代沉船是中国目前发现的保存最为完整的古代木制沉船之一,已于2022年11月完成整体打捞。在进行水下考古调查时,沉船出水的部分青花瓷出现的病害现象引起了考古工作者的关注,特别是裂纹中黑色污染物及表面铁锈状污染物对文物的外观产生了很大影响。本工作选取了三件具有典型被污染特征的青花瓷标本作为代表,使用能量色散X射线荧光分析(EDXRF)、光学显微镜(OM)、X射线衍射分析(XRD)、拉曼光谱分析(Raman)和扫描电子显微镜-能谱分析(SEM-EDS)等方法,对污染物进行了研究,探讨了其形成原因以及环境的影响作用,并对其潜在危害进行了分析。研究表明,污染物主要以方解石、菱铁矿等碳酸盐以及铁的氧化物、氢氧化物和硫化物为主。长期处于河口淤泥中的还原性环境是导致菱铁矿和亚稳的铁硫化物形成的原因,船体中铁质构件腐蚀对局部环境的污染是重要的影响因素,这也反映出被污染的青花瓷所处位置和环境的特殊性。出水的部分青花瓷釉中裂纹的形态表明其形成是由物理撞击造成,而釉中硅灰石晶体的选择性腐蚀会导致腐蚀坑的形成,裂纹和腐蚀坑均为外部污染物进入釉层内部提供了通道,导致瓷器劣化。出水后...  相似文献   
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