长岭断陷火石岭组原型盆地特征及勘探方向分析

The Characteristics of the Huoshiling Fm Prototype Basin and Exploration Direction in Changling Fault Depression

松辽盆地长岭断陷经多期改造致使现今残留盆地与盆地原型特征差异较大,拓展火石岭组勘探阵地受到一定的局限。在残留盆地特征研究基础上,依据该区地质背景及资料情况,在系统考虑各种方法适用范围及影响因素的前提下,针对不同的井或地区选用了声波时差法、镜质体反射率法、剖面趋势法等计算长岭断陷火石岭组的地层剥蚀量,并恢复了研究区该时期的盆地原型,明确了其特征。在成藏地质条件分析基础上,指出西部斜坡带上火石岭组超覆带与西部、南部断阶带残留箕状洼陷内构造高部位(火山岩体)是本区油气勘探的有利方向。

In Changling fault depression of Songliao Basin, residual basin is quite different from prototype basin due to multiple re working, and the exploration on Huoshiling Fm to extend the resource is very difficult. On the basis of the study on the characteristics of residual basin, the geological background and available data, the denudation quantity of the Huoshiling Fm has been calculated, and prototype basin at this sedimentation period has been restored with acoustic travel time method, vitrinite reflectance method and the profile trend method, and the reservoir characteristic has been made clear. On the basis of the study results on the geologi cal conditions for HC accumulation, the favorable HC exploration targets have been point out, mainly Huoshiling Fm stratigraphic onlapping zone in the western slope belt and the structural high position （volcano rock） of residual dustpanlike sag in western and southern fracture zones.