轮古7井区三叠系砂岩储层黏土矿物特征及敏感性损害研究

摘要

The reservoir in Lungu 7 well field in Tarim Oilfield belongs to middle to high porosity and middle to high permeability reservoir.In order to research some of those damage factors in the process of mining,based on the rock properties and mineral composition characteristics,the sensitivity test evaluation method is applied to analyze the sensitivity damage mechanism of Triassic reservoir in Lungu 7 well field.The result shows that velocity sensitive damage does not necessarily exist in the middle-high porosity and permeability reservoir with high content of kaolinite.The velocity sensitive damage caused by kaolinite which is outputed by feldspar dissolution and limited in particle feldspar is smaller,but the alkali sensitive damage is larger.Illite which outputs on the clastic particle surface in the form of capsule has a little velocity sensitive damage.illite-smectite mixed-layer with a slice of pore filling type output mainly causes water sensitivity effect.It is considered that Triassic reservoir in Lungu 7 well field has the characteristics of medium-strong alkali sensitivity,medium water sensitivity,medium weak dilute sensitivity and no velocity sensitivity.%塔里木油田轮古7井区油藏为中—高孔、中—高渗储层,为了研究该储层在开采过程中的伤害因素,在了解其岩石性质及矿物成分特征的基础上,利用敏感性实验评价方法,分析了轮古7井区三叠系油藏储层损害机理。研究表明：高岭石含量高的中—高孔、中—高渗油藏不一定存在速敏损害;由长石溶蚀改造而产出并局限于长石颗粒铸模内的高岭石引发的储层潜在速敏损害较小,碱敏损害较大;呈包膜形式产出并以石英为主的碎屑颗粒表面的伊利石对储层潜在速敏损害较小;呈片状以孔隙充式填产出的伊/蒙混层主要引发水敏效应。另外,轮古7井区三叠系油藏还具有中等偏强碱敏、中等水敏、中等偏弱酸敏和无速敏的特征。