CAJ | 학술논문

油气储层中不同时期所充填的矿物和流体包裹体可以揭示油气的成藏过程。四川盆地高石梯构造震旦系灯影组储层至少有3期矿物充填：白云石→沥青→石英／白云石＋石英。早期的白云石中富含油包裹体；晚期的石英中富含液态甲烷包裹体，烃类包裹体的捕获压力为79．4～98．12 MPa，压力系数为1．35～1．88，显示超压特征。现今气藏的压力系数为1．06～1．13。高石梯气藏具有多期成藏特点，属于构造调整气藏。其可能的成藏过程为：二叠纪－三叠纪末期，古油藏形成；侏罗纪－晚白垩世，古油藏中的石油在原位开始裂解形成超压古气藏；喜马拉雅早期，古气藏向资阳－威远方向迁移和被破坏；喜马拉雅中晚期，磨溪地区的古气藏迁移调整至高石梯地区重新成藏。在调整成藏过程中，气藏具有从超压向常压演变的特征。古气藏的破坏、侧向迁移和重新聚集成藏，可能主要受构造演化和构造高点的侧向迁移控制。
유기저층중불동시기소충전적광물화류체포과체가이게시유기적성장과정。사천분지고석제구조진단계등영조저층지소유3기광물충전：백운석→력청→석영／백운석＋석영。조기적백운석중부함유포과체；만기적석영중부함액태갑완포과체，경류포과체적포획압력위79．4～98．12 MPa，압력계수위1．35～1．88，현시초압특정。현금기장적압력계수위1．06～1．13。고석제기장구유다기성장특점，속우구조조정기장。기가능적성장과정위：이첩기－삼첩기말기，고유장형성；주라기－만백성세，고유장중적석유재원위개시렬해형성초압고기장；희마랍아조기，고기장향자양－위원방향천이화피파배；희마랍아중만기，마계지구적고기장천이조정지고석제지구중신성장。재조정성장과정중，기장구유종초압향상압연변적특정。고기장적파배、측향천이화중신취집성장，가능주요수구조연화화구조고점적측향천이공제。
The process of hydrocarbon accumulation can be revealed by the different minerals and fluid inclusions filled at different stages in the reservoirs.At least three generations of mineral filling can be identified in the Sinian Dengying Formation reservoir in the Gaoshiti structure of Central Sichuan. They are dolomite→bitumen→quartz/dolomite+quartz.The early dolomite and later quartz are rich in oil inclusions and liquid CH4 inclusions,respectively.The trapping pressure (79.4~98.12 MPa) and the pressure coefficient (1.35~1.88)of CH4 inclusions in the quartz indicate that the ancient gas pools are characterized by overpressure.The pressure coefficient of the present gas pools is 1 .06~1 .1 3 .The research indicates that the Gaoshiti gas pool is characterized by multi-phase hydrocarbon accumulation and belongs to a tectonic adjustment gas pool.A possible process of hydrocarbon accumulation can be suggested as follows.(1)The ancient oil pool formed during Permian-the end of Triassic;(2 ) The petroleum thermal cracking in situ resulted in the development of ancient overpressure gas pools during Jurassic-Late Cretaceous;(3)The gas in the ancient gas pools migrated toward the Ziyang-Weiyuan and the ancient gas pools were destroyed in the early Himalaya period;(4)The gas from the Moxi ancient gas pools migrated to Gaoshiti structure and reformed new gas pools there in the middle-late Himalaya period.The pressure of gas pools decreased from overpressure to normal pressure during the adjustment and re-accumulation of hydrocarbon.The tectonic evolution and the lateral migration of the structural crest were responsible for the lateral migration and the destruction of the ancient gas pools and re-accumulation of hydrocarbon.