Based on analyses of the components of crude oil hydrocarbons and carbon isotopes,the content of normal alkane decreased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the ...Based on analyses of the components of crude oil hydrocarbons and carbon isotopes,the content of normal alkane decreased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the Qaidam Basin,while cycloalkanes increased from 30.00% to 52.20% and aromatic and branch chain alkanes increased gradually as well. The maturity of sterane in crude oil is higher than that of its source-rock,which shows that the hydrocarbons were generated from a deep source-rock of high maturity around the tectonic belts of the Lenghu area. The analysis of the characteristics of carbon isotopes also shows that these isotopes of hydrocarbon compounds in the No.4 and No.5 tectonic belt are apparently heavier than those in the No.3 belt. The results of our research show that the hydrocarbons in the No.3 tectonic belt are mainly from a relatively rich sapropelic substance,while the hydrocarbons in the No.4 and No.5 tectonic belt originated mainly from organic matter of a relatively rich humic type substance.展开更多
Based on the analyses of Loss-on-Ignition （LOI）, carbonate content and sediment characteristics, this paper reconstructs the climatic and environmental evolution of the Gahai lake area since the late Last Deglacial ...Based on the analyses of Loss-on-Ignition （LOI）, carbonate content and sediment characteristics, this paper reconstructs the climatic and environmental evolution of the Gahai lake area since the late Last Deglacial Period. The results cover the late Last Deglacial Period and the Holocene. The climate was very unstable and rather arid during the late Last Deglacial Period. The Holocene can be divided into three periods： the early Holocene （11360-8240 cal aB. P. ）, which was dry but unstable and featured rising temperatures, the mid-Holocene （8240-3200 cal aB. P. ）, which was warm and wet and the late Holocene （ since 3200 cal aBP）, which was cold and dry. Results also show a warm-wet event around 1500 cal aB. P.展开更多
基金Project 2009011 supported by the Resource Exploration Projects of the Ministry of Land and Resources of Chinathe State Key Laboratory of Petroleum Resource and Prospecting of China Petroleum University (Beijing)
文摘Based on analyses of the components of crude oil hydrocarbons and carbon isotopes,the content of normal alkane decreased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the Qaidam Basin,while cycloalkanes increased from 30.00% to 52.20% and aromatic and branch chain alkanes increased gradually as well. The maturity of sterane in crude oil is higher than that of its source-rock,which shows that the hydrocarbons were generated from a deep source-rock of high maturity around the tectonic belts of the Lenghu area. The analysis of the characteristics of carbon isotopes also shows that these isotopes of hydrocarbon compounds in the No.4 and No.5 tectonic belt are apparently heavier than those in the No.3 belt. The results of our research show that the hydrocarbons in the No.3 tectonic belt are mainly from a relatively rich sapropelic substance,while the hydrocarbons in the No.4 and No.5 tectonic belt originated mainly from organic matter of a relatively rich humic type substance.
文摘Based on the analyses of Loss-on-Ignition （LOI）, carbonate content and sediment characteristics, this paper reconstructs the climatic and environmental evolution of the Gahai lake area since the late Last Deglacial Period. The results cover the late Last Deglacial Period and the Holocene. The climate was very unstable and rather arid during the late Last Deglacial Period. The Holocene can be divided into three periods： the early Holocene （11360-8240 cal aB. P. ）, which was dry but unstable and featured rising temperatures, the mid-Holocene （8240-3200 cal aB. P. ）, which was warm and wet and the late Holocene （ since 3200 cal aBP）, which was cold and dry. Results also show a warm-wet event around 1500 cal aB. P.
