本文選題：碳酸鹽巖 + 埋藏溶蝕�。� 參考：《沉積學報》2017年02期

【摘要】：鄂爾多斯盆地奧陶系碳酸鹽巖儲層受埋藏溶蝕作用控制明顯,而地層深部復雜的水—巖反應造成埋藏溶蝕研究難度較大,并進而影響了儲層的評價與預測。分別利用CO_2溶液和乙酸溶液為流體介質進行溶蝕模擬實驗,探討埋藏條件下溫度、壓力、流體等因素對不同礦物及組構碳酸鹽巖溶蝕作用的影響。結果表明:1)隨著溫度與壓力升高,碳酸鹽巖樣品在乙酸溶液中的溶解速率均相應提高,在CO_2溶液中的溶解速率則先增加后減小,且在110℃~130℃區(qū)間內溶蝕速率最大;深埋藏環(huán)境下,各巖類溶蝕速率差異減小,并趨于一致;2)巖石礦物成分和組構,原巖初始孔隙度的大小及其連通關系,以及晶體的產狀對成巖后期的埋藏溶蝕作用也具有重要的影響。不溶組分含量低、顆粒/灰泥比高、礦物成分復雜的碳酸鹽巖由于組構選擇性溶蝕作用而更易被溶蝕;碳酸鹽巖的溶蝕速率隨方解石含量的增加而增加,但深埋藏環(huán)境下,礦物成分含量差異對溶蝕速率的影響作用減弱;硬石膏與白云巖相伴生時,可優(yōu)先溶蝕形成膏�？�,并促進白云石的溶解,改善儲層效果。不同巖性,總體上灰?guī)r較白云巖及過渡巖類更易發(fā)生埋藏溶蝕作用。結合研究區(qū)實際地質條件分析,砂屑灰?guī)r、膏質白云巖等埋藏溶蝕強度較大,通過對原巖早期組構選擇性溶蝕形成孔隙的繼承和調整,疊加埋藏期巖溶作用后,可形成規(guī)模優(yōu)質儲層。
[Abstract]:Ordovician carbonate reservoirs in Ordos Basin are obviously controlled by buried dissolution, but it is difficult to study buried dissolution due to complex water-rock reactions in the deep strata, which further affects the evaluation and prediction of reservoirs. In this paper, CO_2 solution and acetic acid solution were used as fluid medium to study the effects of temperature, pressure, fluid and other factors on dissolution of different minerals and fabric carbonate rocks. The results show that with the increase of temperature and pressure, the dissolution rate of carbonate rock in acetic acid solution increases and then decreases in CO_2 solution, and the dissolution rate is the highest in the range of 110 鈩，

本文編號：1946407