摘要
莺歌海盆地沉积中心的T_2至T_σ反射层,是沉积巨厚的富含有机质的泥岩,埋藏于生油门限深度3250m以下,有机质业已成熟并生成烃类,使泥岩孕育着高温、高压状态的烃类聚集。盆地边缘沉积的粗粒砂砾,沿着盆地基底斜坡向沉积中心下滑产生的侧应力,使沉积中心巨厚的泥岩沿着纵向上的断裂和裂缝上拱,产生泥岩底辟形成泥丘构造。泥丘两侧及顶部的圈闭构造,捕获从生油岩中形成的油气及泥岩上拱过程中释放的油气,而聚集成藏。
The seismic reflections of T2 -T6 in the depocenter of the Yingge Sea Basin are of thick argillite sequences with rich organism. Since the organic matters in the sequences have been buried at depth over 3250m, i. e the oil/gas generating threshold,they are already transformed into hydrocarbon and the oil/gas accumulation occurred under the high pressure/high temperature in the argillite sequences. Because of the coarse grained ?granules deposited at the margin of the basin and their downslidings along the basement towards the depocenter, it brought about lateral compression. Consequently, the thick argillite sequences in the depocenter upwarped along the vertical fractures and faults and the mudlump diapirism caused the formation of mudcone structures. The trap structures developed in the sequences of T2 -T6 reflections at the both flanks of the mudcone and its top part could trap the oil/gas generated from source rocks and the hydrocarbon released during the stage of mudlump upwarping, being formed into oil/gas pools.
出处
《石油实验地质》
CAS
CSCD
北大核心
1992年第3期244-251,共8页
Petroleum Geology & Experiment
