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1.
Robert L. Bettinger 《Journal of Archaeological Research》1993,1(1):43-66
Great Basin archaeologists spent the 1970s and most of the 1980s tearing down the Desert Culture hypothesis without presenting compelling means for dealing with the empirical variability that made it untenable. Recent research seeks to understand this variability by examining the effect of key variables in extreme environmental contexts, especially in wetlands and at high altitudes, and by developing and refining models of optimality that anticipate variability as the local expression of general evolutionary ecological principles. Research on intraregional and ethnic variability has lagged behind—the former because it is said to be costly, the latter because it is problematical in theory. 相似文献
2.
David W. Haig 《Alcheringa: An Australasian Journal of Paleontology》2018,42(1):37-66
Haig, D.W., October 2017. Permian (Kungurian) Foraminifera from Western Australia described by Walter Parr in 1942: reassessment and additions. Alcheringa 42, 37–66. ISSN 0311-5518.Exceptionally well-preserved siliceous agglutinated Foraminifera originally recorded by Walter Parr in 1942 are redescribed and illustrated by rendered multifocal reflected-light images. Significant new observations are made on wall texture and apertural morphology. The specimens are from the Quinnanie Shale and lower Wandagee Formation in the Merlinleigh Sub-basin of the Southern Carnarvon Basin, a marginal rift that splayed from the East Gondwana interior rift. During the Early Permian, a restricted shallow sea inundated the rift. The formations are part of sequence III of the Byro Group and belong within the Kungurian Stage (Cisuralian, Lower Permian). Of the 14 agglutinated species described by Parr, six are retained under their original names, viz., Hyperammina coleyi Parr, 1942, H. rudis Parr, 1942, Ammodiscus nitidus Parr, 1942, A. wandageeensis Parr, 1942, Tolypammina undulata Parr, 1942 and Reophax tricameratus Parr, 1942; one is transferred to a different species, viz., Thurammina texana Cushman &; Waters, 1928a; six are placed with other genera, viz., Thuramminoides pusilla (Parr, 1942), Teichertina teicherti (Parr, 1942), Sansabaina acicula (Parr, 1942), Tolypammina? adhaerens (Parr, 1942), Kunklerina subasper (Parr, 1942), Trochamminopsis subobtusa (Parr, 1942); and a species of Ammobaculites Cushman, 1910 identified by Parr is now left in open nomenclature. From Parr's material, eight additional species are described: two new species, viz., Hyperammina parri sp. nov. and Gaudryinopsis raggatti sp. nov.; rare representatives of Aaptotoichus quinnaniensis Haig, 2003; and very rare species of Lagenammina Rhumbler, 1911, Giraliarella Crespin, 1958, Glomospira Rzehak, 1885, Hormosinella Shchedrina, 1969, and Reophax Denys de Montfort, 1808, all of which are left in open nomenclature. Hyperammina rudis is the type species of Hyperamminita Crespin, 1958, a genus now considered a junior subjective synonym of Hyperammina Brady, 1878. Thuramminoides pusilla is considered a senior subjective synonym of T. sphaeroidalis Plummer, 1945, the type species of Thuramminoides Plummer, 1945. Imagery is presented confirming that the simple cylindrical canals through the wall of Teichertia teicherti differ from the branching canals in Crithionina rotundata Cushman, 1910, type species of Oryctoderma Loeblich &; Tappan, 1961. The collection contains some of the earliest representatives of the revised family Verneuilinoididae Suleymanov, 1973, herein elevated from subfamily rank, and considered to include Pennsylvanian–Cisuralian representatives of Mooreinella Cushman &; Waters, 1928a, Aaptotoichus Loeblich &; Tappan, 1982, Digitina Crespin &; Parr, 1941, Gaudryinopsis Podobina, 1975, Caronia Brönnimann, Whittaker &; Zaninetti, 1992 (=Palustrella Brönnimann, Whittaker &; Zaninetti, 1992) and Verneuilinoides Loeblich &; Tappan, 1949.David W. Haig [david. haig@uwa. edu. au] Centre for Energy Geoscience, School of Earth Sciences, University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia. 相似文献
3.
Gregory J. Retallack 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):475-500
Earliest Triassic shales in the Coal Cliff Sandstone, Caley Formation, Widden Brook Conglomerate and Dooralong Shale (all basal Narrabeen Group) of the Sydney Basin contain a low diversity fossil flora that survived the greatest mass extinction of all time at the Permian-Triassic boundary. Only one species of seed fern is known from this flora and its affinities were unclear until discovery of its reproductive organs and complete large leaves. An ovuliferous reproductive organ, Peltaspermum townrovii sp. nov., can be attributed to the same plant as the leaves because of their identical stomatal apparatus, which is cyclocytic with papillae overhanging the stomatal pit. Polleniferous organs, Permotheca helbyi sp. nov., may have belonged to the same plant, but are only linked by evidence of association on the same bedding plane yielding no other gymnosperms. Pollen masses found within the polleniferous organ include grains identified as Falcisporites australis (de Jersey) Stevens (1981) when found dispersed. The leaves of this plant have long been enigmatic and attributed to ‘Thinnfeldia’ callipteroides or ‘Dicroidium’ callipteroides; however, these genera had very different cuticular structure. Reassessment of the frond architecture of this plant, based on a large, nearcomplete specimen together with information from cuticles and ovuliferous organs, allows reassignment to Lepidopteris callipteroides (Carpentier) comb. nov. The remarkable cuticle thickness, small stomatal size and low stomatal index of these leaves reflect a time of unusually high atmospheric concentrations of carbon dioxide. This plant was an invader of the Sydney Basin from northern Gondwana, spreading southward during the post-apocalyptic earliest Triassic greenhouse. 相似文献
4.
Fluid mixing induced by hydrothermal activity in the ordovician carbonates in Tarim Basin,China 下载免费PDF全文
Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration. 相似文献
5.
Jon W. Carroll 《Midcontinental journal of archaeology, MCJA》2019,44(2):181-206
The original ceramics typology developed for Younge/Western Basin Tradition Springwells phase (ca. AD 1160–1420) assemblages included three variants known as Macomb Linear, Macomb Interrupted Linear, and Springwells Net Impressed ceramics. This discussion considers how subregional variation in Springwells decorative styles reflects participation in a larger regional social network. 相似文献
6.
广东五邑地区以潭江流域为中心,是一个相对独立的地理单元,但该地的政区边界却打破了自然山川的界限。从明代到清初顺治年间,为了应对以民变为首的地方政治危机,朝廷先后在潭江流域设置了恩平、新宁、开平三县。这些县级政区的边界大致与潭江流域的地理分界线重合,地理单元的独立性开始作用于政区划界中。清代雍乾年间,形成了新会、鹤山、新宁、开平、恩平五县分治潭江流域的格局。同时,随着新会县核心政区地位的巩固,流域内各县整合为一个统县政区的倾向开始加强,为后世潭江流域的政区整合奠定基础。明清时期潭江流域的政区变迁体现了地理环境和地方政治局势在政区格局形成过程中的根本性作用。 相似文献
7.
River basins are an extremely important source of freshwater for Africa and the impact of climate change on these communities constitutes an important question worth studying. Among these basins, the Niger River Basin is an ideal candidate for meso-level theory testing of climate change-induced political violence because of its importance as one of the largest sources of freshwater in Africa, its high vulnerability to climate change, and its location in a politically unstable region. This paper utilizes the benefits of GIS to test whether effects of water insecurity on the various incidences of political violence are conditional on economic, geographic, and social means of connectivity. Our analysis uses the density of secondary road networks, the geographic distance to the Niger River, and a shared co-ethnicity with one's head-of-state to evaluate the impact of hydrological stress and its subsequent risk for political violence across nine West African countries from 1997 to 2012. Using climatological data and an econometric de-trending method, we measure the separate, substantive impact that individualized changes in precipitation trend and precipitation variability have for the incidence of ACLED's political violence events, conditional on local economic, geographic, and social factors. Our results reveal a complicated web of circumstances under which certain forms of political violence are more/less likely to be observed. The implications of this analysis serve as a call for a closer inspection of the micro-channels by which climate stress impacts heterogeneous communities in the developing world. 相似文献
8.
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
9.
K. Khler Gy. Plfi E. Molnr I. Zalai‐Gal A. Oszts E. Bnffy K. Kirin K. K. Kiss B. G. Mende 《International Journal of Osteoarchaeology》2014,24(6):697-703
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
10.
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