“未熟油”与“未熟生烃”异议  

Dissent over "Immature Oil" and "Generation of Hydrocarbon by Immature Source Rocks"

作　　者：陈安定[1] 

机构地区：[1]江苏石油勘探局地质科学研究院,江都225261

出　　处：《地质论评》1998年第5期470-477,共8页Geological Review

摘　　要：有关专家认为,“未熟生烃”是我国新生代盆地广泛存在的地球化学现象。本文剖析了这一论点背后隐含的矛盾,并以苏北盆地部分断陷中存在的“不等深等温”、“不等深等熟”、成熟度指标与埋深关系的“平行变浅”分布等资料为依据,提出此现象当源于“古大于今”埋深史这一特定地质背景(或称为退化型受热史)。若以恢复的最大古埋深重新勾画产烃率曲线,所谓“低温早熟”现象即可消除。既然未熟生烃现象不存在,也就不存在未熟的石油。同时指出,对此类盆地的后期抬升幅度及其不均衡性估计不足是产生这一认识的主要根源。Some specialists hold that the generation of hydrocarbons by immature source rocks is a prevalent geochemical phenomenon in many Cenozoic basins of China. This view contains a contradiction. In some fault depressions of the Subei basin, eastern China, there exist the equal subsurface temperature and the same maturity at different depths and the parallel-shallowing distribution of the maturity index and the burial depth of the samples. This phenomenon is due to the particular geological setting of the ancient burial depths being greater than the present ones (or called the degenerative thermal .history). If a curve of the hydrocarbon yield is drawn with the restored maximum palaeoburial depths, the phenomenon of earlier generation of hydrocarbons at low subsurface temperatures can disappear. Now that the phenomenon of hydrocarbon generation by immature source rocks does not exist, no immature oil will exist. The wrong view of hydrocarbons generation by immature source rocks mainly originate from the underestimation of the u-plift amplitude of such basins in the late stage and the unbalance of the uplift.

关 键 词：未熟油 未熟生烃 古埋深 生油理论 油矿床 

分 类 号：P618.130.1[天文地球—矿床学]