Thermal and maturation history for Carboniferous source rocks in the Junggar Basin, Northwest China: implications for hydrocarbon exploration  

作　　者：Di Hu Song Rao Zhu-Ting Wang Sheng-Biao Hu 

机构地区：[1]State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing 100029,China [4]Key Laboratory of Exploration Technologies for Oil and Gas Resources,Ministry of Education,Yangtze University,Wuhan 430100,Hubei,China

出　　处：《Petroleum Science》2020年第1期36-50,共15页石油科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.41502236 and 41877210);the National Foundation for Science and Technology Development(No.2017ZX05008-004).

摘　　要：The reconstruction of thermal history is an important component of basin evolution and hydrocarbon exploration.Based on vitrinite reflectance data,we integrate the paleo-temperature gradient and paleo-heat flow methods to reconstruct the thermal history of Junggar Basin.Compared with present thermal state,the Junggar Basin experienced much a higher heat flow of ca.80–120 mW/m2 during the Carboniferous.This feature can be attributed to large-scale volcanic events and related thermal effects.The hydrocarbon maturation history of Carboniferous source rocks indicates that the temperature rapidly reached the threshold of hydrocarbon generation during the Late Carboniferous and has never achieved such a high level since then.This characteristic resulted in the early maturation of hydrocarbons in Carboniferous source rocks.Meanwhile,the results reveal that hydrocarbon maturities are different among various tectonic units in Junggar Basin.The kerogen either rapidly broke through the dry gas period so that cracking of gas occurred or remained in the oil maturation window forming oil reservoirs,which depended on the tectonic background and depositional environment.In this study,we present the thermal and hydrocarbon maturation history since the Carboniferous,which has important implications for further hydrocarbon exploration in Junggar Basin.The reconstruction of thermal history is an important component of basin evolution and hydrocarbon exploration. Based on vitrinite reflectance data, we integrate the paleo-temperature gradient and paleo-heat flow methods to reconstruct the thermal history of Junggar Basin. Compared with present thermal state, the Junggar Basin experienced much a higher heat flow of ca.80–120 mW/m2 during the Carboniferous. This feature can be attributed to large-scale volcanic events and related thermal effects. The hydrocarbon maturation history of Carboniferous source rocks indicates that the temperature rapidly reached the threshold of hydrocarbon generation during the Late Carboniferous and has never achieved such a high level since then.This characteristic resulted in the early maturation of hydrocarbons in Carboniferous source rocks. Meanwhile, the results reveal that hydrocarbon maturities are different among various tectonic units in Junggar Basin. The kerogen either rapidly broke through the dry gas period so that cracking of gas occurred or remained in the oil maturation window forming oil reservoirs, which depended on the tectonic background and depositional environment. In this study, we present the thermal and hydrocarbon maturation history since the Carboniferous, which has important implications for further hydrocarbon exploration in Junggar Basin.

关 键 词：THERMAL HISTORY Hydrocarbon MATURATION modeling VITRINITE reflectance CARBONIFEROUS Source rocks JUNGGAR Basin 

分 类 号：P618.13[天文地球—矿床学]