CAJ | 학술논문

鄂尔多斯盆地华池—合水地区是典型的致密油气富集区，储层物性差，微观孔喉结构特征复杂，孔喉结构对油气的富集和后期开采有较大影响。利用压汞—恒速压汞法探讨华池—合水地区延长组长7致密砂岩储层纳米孔喉定量表征及孔喉体系中流体渗流特征。研究表明：研究区储层排替压力较高，平均喉道半径较小，孔喉体积比及孔喉比较大，渗流能力差；不同物性岩样的孔隙半径分布范围一致，喉道分布差异明显，进汞饱和度随孔隙个数的增多而增大；SHg—ΔSHg／ΔPc 曲线能较好地反映进汞速率及孔喉结构，致密储层中纳米级孔喉发育，且对储层储集及渗流能力有较大的贡献；流体在注入过程中，首先进入孔隙主控区，紧接着进入孔喉共控区，最后进入喉道主控区；恒速压汞在研究致密储层孔喉结构时不能反映纳米孔喉特征，评价物性较好的储层效果较好。
악이다사분지화지—합수지구시전형적치밀유기부집구，저층물성차，미관공후결구특정복잡，공후결구대유기적부집화후기개채유교대영향。이용압홍—항속압홍법탐토화지—합수지구연장조장7치밀사암저층납미공후정량표정급공후체계중류체삼류특정。연구표명：연구구저층배체압력교고，평균후도반경교소，공후체적비급공후비교대，삼류능력차；불동물성암양적공극반경분포범위일치，후도분포차이명현，진홍포화도수공극개수적증다이증대；SHg—ΔSHg／ΔPc 곡선능교호지반영진홍속솔급공후결구，치밀저층중납미급공후발육，차대저층저집급삼류능력유교대적공헌；류체재주입과정중，수선진입공극주공구，긴접착진입공후공공구，최후진입후도주공구；항속압홍재연구치밀저층공후결구시불능반영납미공후특정，평개물성교호적저층효과교호。
Huachi-Heshui area in the Ordos Basin is a typical enrichment region for tight reservoirs. It has poor physical properties and complicated characteristics of microscopic pore throat structure, which has a great effect on oil and gas accumulation and exploitation. Mercury injection and rate?controlled mercury penetration were used to quantitatively characterize nanometer pore throats and to study fluid mobility characteristics in tight sandstone reser?voirs in the seventh member of the Yanchang Formation (Chang7). The reservoir in the study area has high dis?placement pressure, low average throat radius, large pore/throat volume ratio, big pore throat and poor permeability. The distribution range of pore radius of rock samples with different properties is consistent, while the distribution of throat geometry among them is obviously different. Mercury injection saturation increases with the increase of pore numbers. The curve of SHg-ΔSHg/ΔPc can preferably reflect mercury injection velocity and pore throat structure. Nanometer throat pore sare well developed in tight reservoirs, which make a great contribution to reservoir capacity and permeability. In the course of injection, fluid first enters the main controlling area of the pore, then the common control area of pore and throat, and finally the main control area of the throat. Rate?controlled mercury penetration is useful for the reservoirs with good physical properties, but it can not reflect the characteristics of nanometer pore throats in studying the pore throat structure of tight reservoirs.