ANALYSIS OF HYDROCARBON ACCUMULATION CONDITIONS OF THE UPPER PALAEOZOIC SEQUENCE OF THE SOUTHERN NORTH CHINA BASIN

The coal-bearing strata of Carboniferous—Permian of Upper Palaeozoic is a set of good source rock in the Southern North China Basin.However,up to now any great exploration breakthrough has not been achieved.Based on analysis of effective source rock and hydrocarbon preservation,starting from the key factors of controlling hydrocarbon accumulation of Upper Palaeozoic,the important recognition on the hydrocarbon-generation evolution and hydrocarbon preservation condition of main sags has been gained in this paper.Three viewpoints by research are as follows.There is advantaged condition of secondary hydrocarbon generation in the Southern North China and the source rock can produce oil and gas.Taikang Uplift,Luyi Sag and Tanzhuang—Shenqiu Sag had secondary-hydrocarbon condition in Mid Late Yanshanian Period,but there is secondary hydrocarbon in Late Himalayan Period in Niqiuji Sag,which is the focus of looking for the hydrocarbon accumulations that hydrocarbon generated late and reservoir formed late.The modern deep sags are the main hydrocarbon-generation areas and they have advantages condition of hydrocarbon preservation in the Southern North China Basin.