克拉玛依油田六中区下克拉玛依组精细地层对比研究

Fine Stratum Contrast in Lower Karamay Formation of Liuzhong Area of Karamay Oilfield

冲积扇沉积地层厚度变化大,岩性复杂,岩相侧向变化快,给地层对比造成很大困难。通过分析克拉玛依油田六中区下克拉玛依组地层发育和岩相组合特征,确定了研究区标准层对比、旋回对比、等比例对比、相控对比的地层对比原则。研究表明,在地层对比过程中,对于中期旋回,若基准面变化幅度大、分布范围广和识别特征明显,可通过标志层和旋回直接进行识别和对比;对于短期和超短期旋回,若旋回特征受沉积影响较大和部分层段旋回界面不明显,可采用中期旋回约束下的次级旋回进行对比;对厚层叠置砂体或泥岩可采用等比例进行对比;对井间岩相变化大的井可采用相控进行对比。在冲积扇沉积特征研究基础上建立的地层对比原则在地层对比中可起到很好的指导作用。

The alluvial fan deposit varies greatly in stratum thickniss with complex lithologic characters,and changes quickly in lithofacies on laterally,which was great difficulty to the stratum contrast.This article analyzes the stratum development model and lithofacies compages attribute,and establishes the stratum contrast principle including standard stratum contrast,gyration contrast,geometric proportion contrast,and lithofacies control contrast.Its basal level varies greatly and widespreads and the recognition feature is obviously,so the middle gyration can be identified and compared mainly by key bed and gyration directly,while the short and ultrashort period gyrations are affected by the deposition factor.And a part of the gyration interface is not so obvious.So the short and ultrashort period gyration is contrasted mainly by secondary gyration which is restricted by the middle gyration,and the geometric proportion contrast is applied to the thick bedded overriding sand body and claystone,the lithofacies control contrast is applied to wells,in which interwell lithofacies are changed quickly.The stratum contrast principle based on the study of the alluvial fan deposit plays an important role in stratum contrasting.