霸县凹陷西部陡坡带沙三段成岩演化及其对储层物性的影响

发布时间：2018-08-29 16:44

【摘要】：利用岩心观察、岩石薄片分析、物性资料及试油资料,结合盆地埋藏演化史,研究霸县凹陷西部陡坡带岔河集—高家堡地区沙河街组三段(沙三段)扇三角洲成岩作用特征及其对储层物性的影响。结果表明:西部陡坡带沙三段储层目前处于中成岩A期,在持续埋藏的背景下,经历碱性—酸性—碱性成岩环境的演变;成岩演化序列为压实作用/早期碳酸盐胶结—长石溶解/石英次生加大/自生高岭石胶结—灰泥杂基重结晶/晚期碳酸盐胶结/硬石膏胶结/石英弱溶解—黄铁矿胶结。不同沉积相带沉积特征不同,控制成岩演化特征的差异,决定物性演化的不同。扇三角洲平原辫状河道泥质砂岩埋藏早期压实作用较强,后期灰泥重结晶使物性急剧降低,现今主要发育干层。扇三角洲前缘水下分流河道远泥岩端储层,由于酸碱两期溶蚀作用使长石、石英和早期碳酸盐胶结物发生一定程度的溶蚀,油气充注进一步抑制晚期碳酸盐胶结作用,现今保留大量的残余原生孔隙和次生孔隙,可作为良好的油气储集层。扇三角洲前缘席状砂和水下分流河道近泥岩端砂岩早期碳酸盐胶结极为发育,在一定程度上抑制压实作用,但整体上中等的压实作用和较强的胶结作用使物性降低较快,早期碳酸盐胶结堵塞孔隙和喉道,导致酸性流体难以产生大范围的溶蚀,晚期碳酸盐、硬石膏胶结使孔隙度进一步降低,现今物性中等。
[Abstract]:Using core observation, rock slice analysis, physical property data and oil test data, combined with buried evolution history of the basin, The diagenesis characteristics of the third member of Shahejie formation (member 3 of Shahejie formation) and its influence on reservoir physical properties in the western steep slope zone of Baxian sag are studied. The results show that the reservoirs of the third member of Shahejie formation in the western steep slope zone are in the middle diagenetic A stage at present, and under the background of continuous burial, they have undergone the evolution of alkaline, acidic and alkaline diagenetic environment. The diagenetic evolution sequence is compaction / early carbonate cementation feldspar dissolution / quartz secondary increasing / authigenic kaolinite cementation / late carbonate cementation / anhydrite cementation / quartz weak dissolving pyrite cementation. The sedimentary characteristics of different sedimentary facies zones are different, which control the characteristics of diagenetic evolution and determine the difference of physical evolution. In the early burial stage of braided channel argillaceous sandstone in the fan delta plain the compaction is stronger and the physical properties of the silt recrystallization decrease sharply in the late stage. Now the dry layer is mainly developed. In fan delta front subaqueous distributary channel, because of acid-base dissolution, feldspar, quartz and early carbonate cementation occur to a certain extent, and hydrocarbon injection further inhibits late carbonate cementation. At present, a large number of residual primary and secondary pores are retained, which can be used as a good reservoir for oil and gas. The early carbonate cementation of the sandstone near the mudstone end of the fan delta front mat sand and underwater distributary channel is extremely developed, which to some extent inhibits compaction, but on the whole, the medium compaction and strong cementation make the physical properties decrease rapidly. The early carbonate cementation blocked the pore and throat, resulting in a wide range of dissolution of acidic fluids. In the late carbonate and anhydrite cementation, the porosity was further reduced, and the physical properties are moderate.
【作者单位】：中国石油大学(华东)地球科学与技术学院;中国石油大学(华东)海洋国家实验室海洋矿产资源评价与探测技术功能实验室;中国石油华北油田分公司机关开发部;中国石油华北油田分公司第三采油厂;
【基金】：国家自然科学基金项目(41302078) 国家科技重大专项(2011ZX05006-002)
【分类号】：P618.13

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