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1.
For the study of the distribution of the neolithic culture, the collection personally made from the field by Dr. Heanley is a new addition of great interest. It contains 25 stone implements and 12 pieces of pottery from 相似文献
2.
For the study of the distribution of the neolithic culture, the collection personally made from the field by Dr. Heanley is a new addition of great interest. It contains 25 stone implements and 12 pieces of pottery from 相似文献
3.
Distribution and Significance of Carbazole Compounds in Palaeozoic Oils from the Tazhong Uplift, Tarim 总被引：3，自引：0，他引：3
LIU Luofu University of Petroleum Changping Beijing Zhou Jian Fei Zhenbi 《《地质学报》英文版》1998,72(1):87-93
Carbazole compounds in crude oils from the Tazhong uplift of the Tarim basin have been fractionated and detected and successfully used to study petroleum migration and trace source rocks in the study area. Alkylcarbazoles have been found in large amounts in the oil samples analyzed and alkylbenzocarbazoles detected in a small concentration only in part of the samples, but alkyldibenzocarbazoles have not been found in oils. Based on the distribution of G1, G2 and G3 of C2-alkylcarbazoles, the ratio of C3-carbazoles to C2-carbazoles and the relative amounts of alkylcarbazoles and alkylbenzocarbazoles, one can know that the vertical oil migration in the Tazhong uplift is generally from below upward, i.e. from the Ordovician through the Silurian to the Carboniferous. Evidently, source rocks in the uplift should be lower Palaeozoic strata (Ordovician and Cambrian). This study shows that carbazoles are of great importance in the study of petroleum migration and source rocks. 相似文献
4.
There is a long-standing controversy of what triggered the extinction at the Permian-Triassic boundary, the most severe mass extinction in the geologic record, including flood basaltic volcanism and/or bolide impact hypothesis. In order to clarify various pieces of evidence for the mass extinction event at the Permian-Triassic boundary, some researchers from some laboratories throughout the world have made a comprehensive study on a group of samples from the Meishan area of China. Some fresh core samples from the Permian-Triassic boundary in the Meishan area were analyzed in this study. The results showed that there is no Ir anomaly, Moreover, the PGEs patterns of those samples show obvious differentiation characteristics, that is different from the case encountered in meteorites. So no evidence supports the hypothesis of extraterrestrial impact. In contrast, the PGEs patterns are similar to those of Siberian and Emeishan basalts, which indicates that those PGEs are derived mainly from the basalts, lending a support to the correlation between mass extinction at the Permian-Triassic boundary and flood basaltic volcanism. This study has also confirmed the results for samples from section C prior to the analysis of the samples. 相似文献
5.
Calibration of the Albian/Cenomanian Boundary by Ammonite Biostratigraphy: U.S. Western Interior 
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下载免费PDF全文 Robert W. SCOTT 《《地质学报》英文版》2007,81(6):940-948
Calibration of numerical ages to the geological time scale is a long scientific pursuit that requires the integration of multiple data sets. A case study of the Albian/Cenomanian stage boundary, also the Lower/Upper Cretaceous series boundary, illustrates the calibration process. The numerical age of this boundary has shifted from 96 Ma to 99 Ma over a time span of nearly fifty years. Re-calibration resulted first from improvements in radiometric dating, and later from inferences about ammonite phylogeny, and most recently from radiometric dates of newly discovered volcanic beds interbedded with diagnostic guide fossils. However, the calibration process continues with study of cosmopolitan dinoflagellates. 相似文献
6.
《中国地球化学学报》2006,(Z1)
The aim of this research is to study the change of P and N contents of the surface runoff and subsurface flow caused by rainfall events, from the watershed till the stream. Samples were taken and analyzed from the surface runoff water after each rainfall … 相似文献
7.
First Record of Protorosaurid Reptile (Order Protorosauria) from the Middle Triassic of China 总被引：7，自引：0，他引：7
LI ChunInstitute of Vertebrate Paleontology Paleoanthropology Chinese Academy of Sciences Beijing 《《地质学报》英文版》2003,77(4):419-423
A new genus and species of the family Tanystropheidae, Dinocephalosaurus orientalis gen. et sp. nov., is described based on a nearly complete skull. This is the first record of the order Protorosauria from China. It also represents the only known occurrence of Tanystropheidae outside Europe, the Middle East and North America. Dinocephalosaurus is quite similar to Tanystropheus from Monte San Giorgio, Switzerland. Primarily it is distinguished from Tanystropheus in the shape of the premaxilla, maxilla, jugal and parietal. Although the family Tanystropheidae is now referred to the order Protorosauria, the new material from China indicates that the archosauromorph affinities of tanystropheids need further investigation. The discovery of Dinocephalosaurus provides new clues for the study of the evolution and radiation of Protorosauria and Tanystropheidae. It is also important for the study of the eastern Tethyan Fauna and the paleobiogeographical relationship between Europe and southern China in the Triassi 相似文献
8.
Ostracod Biostratigraphy of the Late Cretaceous Qingshankou Formation in the Songliao Basin 总被引：2，自引：0，他引：2 下载免费PDF全文
下载免费PDF全文 ZHANG Zhili LIU Zhenwen WANG Baichang ZHANG Ying YE Dequan 《《地质学报》英文版》2007,81(5):727-738
An ostracod biostratigraphic study was performed on 425 samples from the composite geological section constructed by using cores taken from five selected wells drilled in the Late Cretaceous Qingshankou Formation in the Songliao basin.A total of 19 ostracod zones are established in the formation,of which 3 are newly established and 3 are revised.The 19 ostracod zones are described in detail.This study provides a basis for the detailed stratigraphic division and correlation of the Qingshankou Formation and the Gaotaizi oil reservoir in the oilfield in the Songliao basin. 相似文献
9.
This study assesses the level of contamination of Hg in farmland soils along the irrigating channel downstream from Guizhou Organic Chemical Factory （GOCF）, where metallic mercury is used as a catalyst to produce acetic acid. The total input of mercury into the environment, as announced by GOCF, is 140 t in the past 30 years （1971-2000）. Sampling sites were chosen based on the distance from the source of pollution--the chemical factory. A total of 39 samples were collected from the study area and analyzed for total mercury concentrations and methyl mercury concentrations. The characteristics of vertical and horizontal distributions of total mercury and methyl mercury in the study area （farmland） are described in this paper. Much attention was paid to the transformation of inorganic Hg into organic mercury species in soils as well. The results showed that the farmland has been heavily contaminated by Hg. Land cultivation activity, land utilization style and distance from the pollution source could be the dominant factors controlling the distribution of THg and MeHg. It is observed that active transformation of inorganic Hg into organic mercury species （MeHg） usually takes place in paddy soils. 相似文献
10.
INTRODUCTION The material which forms the present study is collected by Messrs.H. M. Meng, K. Chern and T. Ho from the village of Hopachung, near Kochiu,Yunnan province. According to them, the fossils are recorded from seven localities. 相似文献