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描述了一件象属( Elephas) 的右上臼齿化石。标本产自查谟紧靠上西瓦立克亚群巨砾岩组( Boulder Conglomerate Formation) 之上的砂质、粉砂质泥岩夹砾石层中,化石地点位于查谟市南10 km,Kharian 村北约500 m 处。根据齿板数、齿脊频率、釉质层厚度、冠高指数、绝对大小和齿长/齿高指数等牙齿形态参数,暂时将之归为 Elephas cf. E. maximus indicus。还简短讨论了象属的地理分布和地质时代。  相似文献   
2.
Core-drilling project carried out in the southern margin of the Kathmandu Basin revealed that muddy debris flow deposits dammed up the Proto-Bagmati river to form the Paleo-Kathmandu Lake during the Jaramillo subchron from 1.07 to 0.97 Ma. Subsequent deposition of the alluvial fanglomerate, derived from the uplifting Mahabharat Range to the south, raised the dam deepening the lake-water. After 1 Ma, in the southern part of the basin, palaeo-current directions changed from southward to northward and deposition of gneissose and granitic detritus are replaced by meta-sediments derived from the Mahabharat Range.During the same time, at about 1 Ma, the boulder conglomerates were deposited on top of the Siwalik Group as piggy-back basins in front of an intra-basinal high, along the Main Dung Thrust in Nepal and NW India. Onset of movement of the Main Dung Thrust is dated back to 3 to 2.4 Ma [Mugnier, J.L., Huyge, P., Leturmy, P., Jouanne, F., 2003, Episodicity and rates of thrust-sheet motion in the Himalayas, Western Nepal. Am. Assoc. Petrol. Geol., Mem. 82, 1-24]. The Main Frontal Thrust is most active at present suggesting that imbricated structure of the Siwalik Group was formed by convergence of the Indian plate during the last 3 myr. The accretionary wedge of the Siwalik Group, stacked beneath the Main Boundary Thrust, might have started to jack up the frontal range of the Lesser Himalaya since 1 Ma.Coeval uplift and erosion of the frontal range of the Lesser Himalaya and the intra-basinal high in the Siwalik since 1 Ma are possible causes of an abrupt increase in both sedimentation rate and grain size of detrital quartz, and changes in composition of clay minerals, recorded in the sediments of the Bengal Deep Sea Fan at 0.9 Ma.  相似文献   
3.
In the Himalayan foothills of northern India, evidence of widespread hominin occupation since at least the late Middle Pleistocene has been known since the early 20th century and indicates varied patterns of land-use and intraregional mobility. This lithic evidence primarily belongs to the Soanian industry, representing some of the highest concentrations of Paleolithic assemblages in the Old World based exclusively on pebble and cobble clasts. This body of evidence also signifies interregional dispersal from peninsular India or northern Pakistan, leading to environmental preferences that spread quickly through hominin populations in the region within a relatively short timespan. While rich in its technological repertoire, the Soanian industry is poorly- understood regarding site selection and raw material exploitation over time. Recent efforts demonstrate that Soanian sites on Siwalik frontal slopes between two major rivers vary considerably in their artifact quantities regardless of abundant raw material sources found across the landscape. Most of the assemblages suggest raw material transport distances of three kilometers or less from the localized sources. Geoarchaeological investigations at the richest known Soanian site, Toka, reveal dynamic evidence of pre- and postdepositional site formation including the exploitation of quartzite pebbles and cobbles by Pleistocene hominins from terrace and streambed contexts within a 1 km2 radius. Some field observations also disprove claims made by previous workers, of artifacts eroding out of late Pliocene exposures of the Upper Siwalik Tatrot Formation around Toka.  相似文献   
4.
《Palaeoworld》2015,24(3):324-335
We describe the cricetid rodents represented by Megacricetodon daamsi, Megacricetodon sivalensis, and Myocricetodon sivalensis, recovered from two localities, Dehari and Jhajjar Kotli, lying in the upper part of the Lower Siwalik Subgroup of Jammu Province. The cricetid fauna is similar to that reported from the Pakistan Siwaliks. Based on the species identifications and the stratigraphic range of the cricetid taxa in the Siwalik succession of Pakistan, the age of the Dehari locality is correlated to between 13.8 and 13.2 Ma, whereas an age of 13.8–12.5 Ma would be assigned to the Jhajjar Kotli rodent yielding level. The occurrence of similar rodent taxa at the two investigated sites points to the homotaxial nature of the fossiliferous beds.  相似文献   
5.
印度、尼泊尔晚中新世-上新世SIWALIK-CHURIA群轮藻化石组合与中国塔里木盆地及哈萨克斯坦东南部伊犁盆地轮藻组合极为接近。据此讨论了它们的古生物地理和古生态学特征。中新世-上新世轮藻植物繁盛的原因与当时季风活动引起的季节性洪水泛滥,在广大河漫滩地上形成有利于轮藻植物生长发育的局部湖泊环境有关。  相似文献   
6.
Lawrence J. Flynn 《Geobios》1982,15(4):583-588
Based on the biochronology of rhizomyid rodents of Northern Pakistan, fossil horizons in the Siwaliks of Northern India can be correlated to the late Neogene sequence of Pakistan with greater precision than previously possible. The indian Siwaliks do not include records of the most primitive Rhizomyidae, but rhizomyid faunas of India display strong affinity with those of Pakistan in the late Miocene. Pliocene differentiation of rhizomyid faunas in India and Pakistan may reflect ecological partitioning within the Indian subcontinent. Use of the term «Nagri for deposits at Haritalyangar suggests an erroneous equivalence in age to the Nagri stratotype in Pakistan.  相似文献   
7.
报道和描述了一件平额象左侧M3化石.新材料产自Nangal村附近火山灰层之下的泥岩层,该火山灰是出露于查谟-克什米尔桑巴地区Barakhetar上西瓦立克亚群Nagrota组中年龄为2.48 Ma的火山灰层的延伸.根据齿板数,臼齿长和宽,齿冠长、宽和高,釉质和齿质厚度,齿板长和宽,齿脊频率,冠高指数以及白垩质厚度等齿冠形态参数,暂时将之归为Elephas cf.E.planifrons.新材料的发现将该种的分布上限从2.6 Ma提高到2.48 Ma.  相似文献   
8.
M. P. Singh 《Human Evolution》2003,18(3-4):213-227
The Siwalik Hills have yielded what is perhaps the world’s most ancient early hominid. In December 1992 I discovered a hominid mandibular ramus and a hominid femur in association with stone tools in the Tatrot Formation of the upper Siwalik. The discovery was made from the Tatrot Formation exposed at Khetpurali Village in Haryana, North India. The teeth are bunodont, having a lingually inclined wear plane. The P3 is molariform and single rooted. The femur is platymeric and has medullary stenosis. The stone tools are chopper types. Magnetostratigraphic dating of the Tatrot Formation ranges from 2.47 Myr at the top to 5.44 Myr at the base. The hominid — yielding bed is dated at 3.40 Myr — Middle Pliocene. The palaeoecology of the Tatrot Formation suggests open savannah. The discovery will cast new light on the origin and migration of the early hominids, and hopefully will contribute to a solution of the 100-year-old dispute about the African or Asian origin of humans.  相似文献   
9.
The magnitude of immunological differences between species has been used to estimate the time of divergence of lineages, especially among primates. Calibration of “clocks” based on immunological differences has relied heavily on data from Pakistan suggest that the lineages leading to Mus and Rattus diverged between 14 and 8 million years ago rather than 30 or more million years ago as suggested by techniques invoking constant rates of molecular evolution. Molecular analyses of pairs of mammal species which appear well documented paleontologically should be undertaken in order to expand our understanding of the tempo and mode of molecular evolution.  相似文献   
10.
Lawrence J. Flynn 《Geobios》1982,15(3):327-389
Larges samples of fossil rhizomyids from the Siwalikmolasse deposits of the Potwar Plateau, Pakistan, enable reevaluation of fossil taxa and their evolutionary relationships. Siwalik Rhizomyidae constitute a basis for analysis of poorly represented rhizomyids from other areas in Asia and contribute to biochronological correlation. The extant Tachyoryctinae and Rhizomyinae diverged during the early history of the family and diagnoses of the subfamilies are amended to include extinct genera. Siwalik tachyoryctines include Kanisamys, Protachyoryctes, Rhizomyides, and Eicooryctes nov. gen.; rhizomyines are Brachyrhizomys and Anepsirhizomys nov. gen. Kanisamys, the earliest Siwalik rhizomyid, appeared by about 13 Ma and evolved slowly, displaying stasis in K. sivalensis. Brachyrhizomys evolved from Kanisamys by 9.5 Ma and radiated rapidly. B. nagrii displays rapid increase in size through time. About 7 Ma, Kanisamys and Brachyrhizomys became extinct locally and Protachyoryctes, Eicooryctes, and Rhizomyides appeared, perhaps in response to increasing aridity. After 5.5 Ma, rhizomyids became uncommon in the Potwar and Anepsirhizomys (3.0 Ma) constitutes the latest record of Rhizomyidae in Pakistan.  相似文献   
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