【摘要】：根據(jù)川南—黔中地區(qū)下寒武統(tǒng)黑色頁巖的露頭觀測與鉆井巖心描述、氬離子拋光—掃描電鏡、等溫吸附等方法所獲地球化學(xué)和物性資料,探討了頁巖氣富集條件。研究區(qū)富有機(jī)質(zhì)頁巖沉積相為深水陸棚相、中陸棚相等;有機(jī)碳含量普遍在2%以上;成熟度介于1.32%~4.78%之間,均值為2.85%;主要發(fā)育Ⅰ型干酪根;儲集類型主要以微米-納米孔隙發(fā)育為主,裂縫比較發(fā)育,孔隙度介于0.24%~11.9%之間,滲透率介于(0.000 087~0.535)×10~(-3)μm~2之間,等溫吸附實(shí)驗(yàn)測試平均吸附氣量為2.74m~3/t。黃頁1井現(xiàn)場解析含氣量介于0.16~0.99m~3/t之間,平均含氣量為0.52m~3/t;金石1井現(xiàn)場解析含氣量介于1.51~2.41m~3/t之間,均值為1.8m~3/t。研究表明:四川盆地內(nèi)下寒武統(tǒng)頁巖經(jīng)歷了有利于頁巖氣成藏的長期淺埋—長期隆升—快速深埋—快速抬升的埋藏史及熱演化史且構(gòu)造相對穩(wěn)定,導(dǎo)致其具有較好頁巖氣保存條件;而盆外地區(qū)由于經(jīng)歷了多期次的生排烴,同時(shí)也遭受了多次構(gòu)造運(yùn)動(dòng)的改造,致使頁巖氣藏的保存條件遭到不同程度的破壞。因此,優(yōu)越的物質(zhì)基礎(chǔ)、保存條件等是頁巖氣富集成藏的主控因素。勘探選區(qū)上應(yīng)往四川盆地內(nèi)走,選區(qū)上要尋找有利于頁巖氣成藏的埋藏史及熱演化史的同時(shí)采取"高中找低、強(qiáng)中找弱、好中找厚"的原則。
[Abstract]:Based on the geochemical and physical data obtained from the outcrop observation and drilling core description of the black shale of the Lower Cambrian series, argon ion polishing-scanning electron microscopy and isothermal adsorption, the enrichment conditions of shale gas are discussed. The sedimentary facies of organic-rich shale in the study area is deep-water shelf facies, the middle shelf is equal, the organic carbon content is more than 2%, the maturity is between 1.32% and 4.78%, the average value is 2.85%, the main type 鈪，

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