The Early and Middle Triassic primary lower Yangtze sea basin was formed before the Yangtze and Sino. Korean blocks collided and were assembled. showing the characteristics of an open continental shelf.continental mar...The Early and Middle Triassic primary lower Yangtze sea basin was formed before the Yangtze and Sino. Korean blocks collided and were assembled. showing the characteristics of an open continental shelf.continental margin sea. In order to provide evidence useful for oil and gas exploration in the studied region, this paper centres on the features of the sediments and their facies framework in the basin and the sedimentation parameters such as the deposition rate, palaeotemperature, palaeosatinity, palaeodepth of water and palaeocurrents of the basin.展开更多
There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yang...There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yangtze old land. As a result of the Hunan-Guizhou palaeo-faulting, the crust on the northern side of the fault was uplifted and became land, thus suffering denudation. The bauxitic substances left in the weathered crust evolved and were reworked into bauxite. On the other hand, the crust on the southern side of the fault sank and remained to be part of an ocean. The bauxite deposits of Ia and Ib subtypes were formed by in-situ enrichment of residual bauxitic substances in the weathered crust of the old land, but bauxite deposits of Ic and Id subtypes resulted from transportation, accumulation and sedimentation of allothogenous bauxitic substances on the weathered crust of the old land. The processes of transportation may be distinguished as dry transportation and wet transportation, both of which proceeded under atmospheric conditions.展开更多
By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the E...By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the Eastern Atlantic (EA), the Eurasian (EU), the Bengal / Northern Pacific (BNP), the Western Pacific (WP), the East Asian / Pacific (EAP), and the Huanghe / East Asian (HEA) patterns. Their centers are determined and their yearly intensity indices (1951-1990) are calculated. On this basis the relationship between their interannual variations and the drought / flood in China is examined. It is noted that the EU, HEA and EAP wave trains are closely related to the drought / flood in China. The HEA and EAP patterns strongly influence the precipitation in eastern China. For example, the fierce floods experienced in 1991 early summer over China are related to the weak EAP and strong HEA patterns.展开更多
文摘The Early and Middle Triassic primary lower Yangtze sea basin was formed before the Yangtze and Sino. Korean blocks collided and were assembled. showing the characteristics of an open continental shelf.continental margin sea. In order to provide evidence useful for oil and gas exploration in the studied region, this paper centres on the features of the sediments and their facies framework in the basin and the sedimentation parameters such as the deposition rate, palaeotemperature, palaeosatinity, palaeodepth of water and palaeocurrents of the basin.
基金A project financed by National Natural Science Foundation of China
文摘There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yangtze old land. As a result of the Hunan-Guizhou palaeo-faulting, the crust on the northern side of the fault was uplifted and became land, thus suffering denudation. The bauxitic substances left in the weathered crust evolved and were reworked into bauxite. On the other hand, the crust on the southern side of the fault sank and remained to be part of an ocean. The bauxite deposits of Ia and Ib subtypes were formed by in-situ enrichment of residual bauxitic substances in the weathered crust of the old land, but bauxite deposits of Ic and Id subtypes resulted from transportation, accumulation and sedimentation of allothogenous bauxitic substances on the weathered crust of the old land. The processes of transportation may be distinguished as dry transportation and wet transportation, both of which proceeded under atmospheric conditions.
基金This study is one of the research projects sponsored by the Monsoon Research Foundation of State Meteorological Administration.
文摘By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the Eastern Atlantic (EA), the Eurasian (EU), the Bengal / Northern Pacific (BNP), the Western Pacific (WP), the East Asian / Pacific (EAP), and the Huanghe / East Asian (HEA) patterns. Their centers are determined and their yearly intensity indices (1951-1990) are calculated. On this basis the relationship between their interannual variations and the drought / flood in China is examined. It is noted that the EU, HEA and EAP wave trains are closely related to the drought / flood in China. The HEA and EAP patterns strongly influence the precipitation in eastern China. For example, the fierce floods experienced in 1991 early summer over China are related to the weak EAP and strong HEA patterns.
