朝鲜安州盆地原油地球化学特征

ORGANIC GEOCHEMICAL CHARACTERISTICS OF OILS FROM ANZHOU BASIN,DPR KOREA

安州盆地是朝鲜最大的中新生界陆相含油气沉积盆地。对始新统和下白垩统产层原油的有机地球化学研究表明：始新统原油具有煤成油的主要地化特征，源岩可能为如新统煤系地层；下白垩统原油具有湖相原油一般特征，与朝鲜湾盆地侏罗系原油及株罗系湖相源岩有一致性。安州盆地存在不同类型的油源岩和原油，具有一定的油气勘探远景。

C and GC-MS characterization of the two crude oils from Anzhou basin,DPR Korea,indicates that they have different origins, The oil from Eocene(E_2 ) Xinli group was mainlysourced from coal measures of the Xinli group. It shows the following biomarker characteris-tics : Pr/Ph=3. 87 : BP(bicyc/pentacyclic)=2. 09;having abundant bicyclic sesquiterpenesand aromatized sesquiterpanes; higher content of compound X(pentacyclic triterpanebiomarker of higher plant ) low contents of hopanoids and steroids, and low values ofsteroidslhopanoids(0. 09),(C_(29) +C_(30))hopanes/Tm(3. 32), TNR-1(0. 10) and SF/OF(0.13);and poor in aromatized hopanoids and steroids, These characteristics are very similar tothose of the oils from the Gippsland basin of Australia and the Turpan basin of China, whichare typical coalderived oils.Another oil which is from the lower Cretaceous Longban group, was probably formed inlacustrine sediments. It shows the characteristics such as : Pr/Ph=1. 88; BP=0. 24; highercontents of hopanoids and steroids;(C_(29) +C_(30) hopanes/Tm = 11.8; steroids/hopanoids > 1(having high content of tri-aromatized steroids);containing abundant 3-methyl-phenan-threne and benzothiophenes; having higher values of TNR=1(1. 45) and SF/OF(0. 23),etc.These characteristics are similar to that of Jurassic oil from the offshore Korea basin and therelated Jurassic source rocks.