民和盆地北部油气勘探前景

Prospect for Petroleum Exploration in Northern Minhe Basin

前人大多认为民和盆地北部地区(主要包括周家台低隆和永登坳陷)具有良好的勘探前景。但从构造演化、保存条件、烃源岩发育、主要生烃期与圈闭形成的匹配性及储集层物性等几个主要的石油地质条件对比来看,情况并非如此。由于后期经历的构造反转强度不同,盆地南北部保存条件存在差异,北部地区差于南部巴州坳陷;烃源岩在盆地北部地区的发育亦可能较南部差;主要生烃期与圈闭形成的匹配性,北部地区不如巴州坳陷;受早期深埋的影响,储集层物性在北部地区可能较南部地区更差。总体而言,盆地北部地区的勘探前景不如巴州坳陷。

The northern Minhe basin (e.g.Zhoujiatai low uplift and Yongdeng depression) is previously considered to be of bright prospects for petroleum exploration.However,in view of the principal petroleum geologic factors' comparisons such as structural evolution,preservation,source rock,the match timing between important hydrocarbon generation and trap formation as well as reservoir quality,the situation is not so.The reasons are as follows:1) the preservation condition in the northern Minhe basin is not so good as that of Bazhou depression in the southern Minhe basin due to different post-phase structural reversal intensity;2) the northern Minhe basin may be poorer source rocks than the southern area;3) the match timing between hydrocarbon generation and trap formation in the northern area is not so good as that of Bazhou depression in the southern area;4) having influenced by early deep burial process,the reservoir quality in the northern area could be poorer than in the southern area.Hence,it is believed that the northern Minhe basin may be not so good as Bazhou depression in exploration potentials.