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61.
Chenyang Cai Dave J. Clarke Diying Huang André Nel 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):557-562
Cai, C., Clarke, D.J., Huang, D. & Nel, A., 2014. A new genus and species of Steninae from the late Eocene of France (Coleoptera, Staphylinidae). Alcheringa 38, 557–562. ISSN 0311-5518.A remarkable new genus and species of rove beetle, Eocenostenus fossilis gen. et sp. nov., is described and figured based on one well-preserved specimen from the late Eocene of Monteils (near Alès, Gard, France). Eocenostenus is definitively placed in the extant subfamily Steninae, based on the combination of dense and coarse body punctation, globular and protruding eyes, exposed and closely spaced antennal insertions on the vertex, and six visible abdominal terga. Eocenostenus differs from the two extant stenine genera Stenus and Dianous most notably in the structure of the prothorax, which is strongly transverse and with unusual anterolateral projections, and in the anteriorly placed antennal insertions. This new discovery highlights the palaeodiversity of a genus-poor subfamily and suggests that the early diversification of Steninae is probably complicated.Chenyang Cai [caichenyang1988@163. com] and Diying Huang [dyhuang@nigpas. ac. cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Rd., Nanjing 210008, PR China; Dave J Clarke [dclarke@fieldmuseum. org], Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA; and André Nel [anel@mnhn. fr], Muséum National d’Histoire Naturelle, Institut de Systématique, Evolution, Biodiversité, ISYEB, UMR 7205 CNRS UPMC EPHE, CP50, 45 rue Buffon, F-75005 Paris, France. Received 23.1.2014; revised 2.5.2014; accepted 12.5.2014. 相似文献
62.
Martin Valent Ladislav Marek 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):115-124
VALENT, M., FATKA, O. & MAREK, L., iFirst article. Gracilitheca and Nephrotheca (Hyolitha, Orthothecida) in the Cambrian of the Barrandian area, Czech Republic. Alcheringa, 1–10. ISSN 0311-5518. Five orthothecid hyoliths, Gracilitheca mirabilis sp. nov., Gracilitheca triangularis sp. nov., Gracilitheca sp., Nephrotheca betula sp. nov. and Nephrotheca sp. are described from the ‘middle’ Cambrian Buchava Formation of the Skryje–Tý?ovice Basin in the Czech Republic. The new forms are based on about forty well-preserved external and internal moulds of conchs; opercula of all species remain unknown. Stratigraphic ranges and geographic distributions within the Skryje Tý?ovice Basin are established for all taxa. 相似文献
63.
乌江流域地处西南边陲,境内少数民族众多,宋廷因地制宜,组建了多支少数民族军队。这些地方武力主要由御前屯驻大军和乡军组成,在南宋抗蒙(元)战争中贡献卓著,并与宋朝国祚相始终。此外,它在保卫边防、稳定当地秩序、开发边疆等方面也发挥了积极作用。 相似文献
64.
65.
Abundant illite precipitation in Proterozoic rocks from Northern Lawn Hill Platform, Mt Isa Basin, Australia, occurred in organic matter‐rich black shales rather than in sandstones, siltstones and organic matter‐poor shales. Sandstones and siltstones acted as impermeable rocks, as early diagenetic quartz and carbonate minerals reduced the porosity–permeability. Scanning and transmission electron microscopy (SEM and TEM) studies indicate a relation between creation of microporosity–permeability and organic matter alteration, suitable for subsequent mineral precipitation. K–Ar data indicate that organic matter alteration and the subsequent illite precipitation within the organic matter occurred during the regional hydrothermal event at 1172 ± 50 (2σ) Ma. Hot circulating fluids are considered to be responsible for organic matter alteration, migration and removal of volatile hydrocarbon, and consequently porosity–permeability creation. Those rocks lacking sufficient porosity–permeability, such as sandstones, siltstones and organic matter poor shales, may not have been affected by fluid movement. In hydrothermal systems, shales and mudstones may not be impermeable as usually assumed because of hydrocarbons being rapidly removed by fluid, even with relatively low total organic carbon. 相似文献
66.
Todd A. Surovell Judson Byrd Finley Geoffrey M. Smith P. Jeffrey Brantingham Robert Kelly 《Journal of archaeological science》2009
In this paper, we expand upon a prior study [Surovell, T.A., Brantingham, P.J., 2007. A note on the use of temporal frequency distributions in studies of prehistoric demography. Journal of Archaeological Science 34, 1868–1877.] that explored the problem of taphonomic bias. Taphonomic bias refers to the tendency for younger things to be over-represented relative to older things in the archaeological record due to the operation of destructive processes like erosion and weathering. Using a database of radiocarbon dated volcanic deposits from Bryson, R.U., Bryson, R.A., Ruter, A. [2006. A calibrated radiocarbon database of late Quaternary volcanic eruptions. Earth Discussions 1, 123–124.], we develop an empirical model of taphonomic bias. In contrast to our prior study in which we modeled taphonomic bias as an exponential function wherein the likelihood of site loss remains constant through time, we argue that the probability of site destruction actually decreases with site age. We further demonstrate how this model can be used to correct temporal frequency distributions and extract demographic histories. We illustrate this approach using databases of radiocarbon dates from rockshelter and open-air sites in the Bighorn Basin, Wyoming, USA, and mammoths and humans in Siberia, Russia. 相似文献
67.
乌江流域土司时期的文化环境是该地社会进步、经济发展和民族团结的现实空间,地域特征极其鲜明。一是有深厚的人文积淀,二是强化的汉文化教育,三是开放的文化心态,四是丰富的物质资源,五是鲜明的民族风情,六是剧烈的社会动荡。笔者认为,理清乌江流域土司时期的文化环境,对挖掘该地深厚的土司文化资源,促进现今民族地区的经济发展、社会进步和民族团结具有十分重要的意义。 相似文献
68.
Field sampling and mathematical modeling are used to study the long‐distance transport and attenuation of petroleum‐derived benzene in the Uinta Basin, Utah. Benzene concentration was measured from oil and oil field formation waters of the Altamont‐Bluebell and Pariette Bench oil fields in the basin. It was also measured from springs located in the regional groundwater discharge areas, hydraulically down‐gradient from the oil fields sampled. The average benzene concentration in oils and co‐produced waters is 1946 and 4.9 ppm at the Altamont‐Bluebell field and 1533 and 0.6 ppm at the Pariette Bench field, respectively. Benzene concentration is below the detection limit in all springs sampled. Mathematical models are constructed along a north–south trending transect across the basin through both fields. The models represent groundwater flow, heat transfer and advective/dispersive benzene transport in the basin, as well as benzene diffusion within the oil reservoirs. The coupled groundwater flow and heat transfer model is calibrated using available thermal and hydrologic data. We were able to reproduce the observed excess fluid pressure within the lower Green River Formation and the observed convective temperature anomalies across the northern basin. Using the computed best‐fit flow and temperature, the coupled transport model simulates water washing of benzene from the oil reservoirs. Without the effect of benzene attenuation, dissolved benzene reaches the regional groundwater discharge areas in measurable concentration (>0.01 ppm); with attenuation, benzene concentration diminishes to below the detection limit within 1–4 km from the reservoirs. Attenuation also controls the amount of water washing over time. In general, models that represent benzene attenuation in the basin produce results more consistent with field observations. 相似文献
69.
Charlotte Beck Amanda K. Taylor George T. Jones Cynthia M. Fadem Caitlyn R. Cook Sara A. Millward 《Journal of Anthropological Archaeology》2002,21(4)
Central place foraging models are used to investigate assemblage variability at two Paleoarchaic (terminal Pleistocene/early Holocene) dacite quarries in the central and eastern Great Basin. Our analyses focus specifically on biface reduction and how varying degrees of reduction relate to the costs of transporting the resulting products upon departing the quarry. Our results suggest that when the distance to be traveled to a residential base is great, reduction will proceed further at the quarry than if the residential base is fairly close. Further, a residential site assemblage will consist of bifaces at later stages of reduction than its associated quarry. 相似文献
70.
Zooarchaeological data on small game use hold much potential for identifying and dating Paleolithic demographic pulses in time and space, such as those associated with modern human origins and the evolution of food-producing economies. Although small animals were important to human diets throughout the Middle, Upper, and Epi-Paleolithic periods in the Mediterranean Basin, the types of small prey emphasized by foragers shifted dramatically over the last 200,000 years. Slow-growing, slow-moving tortoises, and marine mollusks dominate the Middle Paleolithic record of small game exploitation. Later, agile, fast-maturing animals became increasingly important in human diets, first birds in the early Upper Paleolithic, and soon thereafter hares and rabbits. While the findings of this study are consistent with the main premise of Flannery's Broad Spectrum Revolution (BSR) hypothesis (Flannery, K. V. (1969). In Ucko, P. J., and Dimbleby, G. W. (eds.), The Domestication and Exploitation of Plants and Animals, Aldine Publishing Company, Chicago, pp. 73–100), it is now clear that human diet breadth began to expand much earlier than the Pleistocene/Holocene transition. Ranking small prey in terms of work of capture (in the absence of special harvesting tools) proves far more effective in this investigation of human diet breadth than taxonomy-based diversity analyses published previously. Our analyses expose a major shift in human predator–prey dynamics involving small game animals by 50–40 KYA in the Mediterranean Basin, with earliest population growth pulses occurring in the Levant. In a separate application to the Natufian period (13–10 KYA), just prior to the rise of Neolithic societies in the Levant, great intensification is apparent from small game use. This effect is most pronounced at the onset of this short culture period, and is followed by an episode of local depopulation during the Younger Dryas, without further changes in the nature of Natufian hunting adaptations. An essential feature of the diachronic and synchronic approaches outlined here is controlling the potentially conflating effects of spatial (biogeographic) and temporal variation in the faunal data sets. 相似文献