本文選題：前陸盆地 + 馬鞍塘組��； 參考：《成都理工大學(xué)》2017年碩士論文

【摘要】：龍門山前緣地區(qū)油氣田(藏)較發(fā)育,油氣勘探前景較好。龍門山前陸盆地地區(qū)多口油氣測試分析出馬鞍塘組油氣潛力巨大,是頁巖氣儲存重要目的層位。通過前人資料收集、野外實測剖面、鉆井巖心觀察、地球化學(xué)分析馬鞍塘組頁巖沉積特征,馬鞍塘組頁巖地球化學(xué)及儲存特征和黑色頁巖的形成機制探討,主要取得了以下的認(rèn)識;(1)馬鞍塘組時期研究區(qū)內(nèi)主要為礁灘相、潮坪-瀉湖相沉積,黑色頁巖主要是瀉湖相沉積。研究區(qū)內(nèi)馬鞍塘組下部為淺海生物碎屑灰?guī)r,上部為淺海粉砂巖、泥頁巖。馬鞍塘組地層厚度在都江堰區(qū)域達到200米以上,地層厚度由龍門山向盆地中部逐漸減薄并出現(xiàn)楔形分布。馬鞍塘組頁巖厚度約為50—120m,在研究區(qū)范圍內(nèi)從南到北頁巖厚底逐漸增大。(2)馬鞍塘組頁巖有機碳含量均大于1%,在雅安地區(qū)馬鞍塘有機碳含量大于2.5。馬鞍塘TOC值從西南部的雅安地區(qū)向北東方向逐漸的減小,這表明遠(yuǎn)離龍門山?jīng)_斷帶區(qū)域地區(qū)逐漸減小。多種類型有機質(zhì)并存,Ⅲ型、Ⅱ2型和Ⅱ1型都有存在,大部分是Ⅲ型,少部分是Ⅱ2型和Ⅱ1型。馬鞍塘組的Ro在雅安地區(qū)大于2.0,從西南部的雅安地區(qū)向北東方向逐漸的減小,表明遠(yuǎn)離龍門山?jīng)_斷地區(qū)Ro值逐漸減小。馬鞍塘組孔隙度0.5%~1.5%,孔隙度較小。馬鞍塘泥頁巖滲透率0.001~0.01mD之間,滲透率低。龍門山山前的都江堰-大邑地區(qū)富有機質(zhì)頁巖累計有效厚度約100m,平均埋深小于4000m,有機碳含量平均值為2.11%,有機質(zhì)成熟度至少是1.25%,總含氣量至少是1.0m3/t,孔隙度約1.1%,地表以平原和低山為主,保存條件良好,是馬鞍塘組頁巖氣勘探前景區(qū)。(3)龍門山前陸盆地富有機質(zhì)頁巖形成機制主要是以下幾個方面,其一,卡尼期危機使得古氣候從干燥變?yōu)闈駶?發(fā)生了生物大滅絕事件,提高了有機質(zhì)生產(chǎn)率。巨型季風(fēng)在晚三疊世早期達到最大,巨型季風(fēng)帶動的洋流在本時期黑色頁巖形成過程中為有機質(zhì)的運移提供了強大動力。位于熱帶的揚子大陸西緣邊緣,巨型季風(fēng)和上升洋流發(fā)育,有機質(zhì)來源豐富;其二,位于龍門山造山楔-前陸盆地-揚子板塊之間,具有封閉的古地貌和缺氧滯留環(huán)境;其三,造山帶構(gòu)造負(fù)載驅(qū)動的撓曲沉降導(dǎo)致前陸盆地具有可容納空間。
[Abstract]:The oil and gas fields (reservoirs) in the front of Longmen Mountain are relatively developed, and the prospects of oil and gas exploration are good. Multiple oil and gas tests in Longmenshan Foreland Basin show that the Maantang formation has great oil and gas potential and is an important target horizon for shale gas storage. Based on previous data collection, field profile, drilling core observation, geochemical analysis of shale sedimentary characteristics of Maantang formation, shale geochemistry and storage characteristics of Maantang formation, and formation mechanism of black shale, the paper discusses the formation mechanism of black shale in Maantang formation. In the study area of Maantang formation, the reef facies, tidal flat and lagoon facies, and the black shale facies are mainly lagoon facies. In the study area, the lower part of Maantang formation is shallow sea bioclastic limestone, the upper part is shallow siltstone and shale. The formation thickness of Maantang formation is more than 200 meters in Dujiangyan area, and the formation thickness decreases gradually from Longmenshan to the middle of the basin and appears wedge distribution. The shale thickness of the Maantang formation is about 50-120 m, and the thickness base of the shale from south to north increases gradually from south to north. The organic carbon content of the shale in the Maantang formation is more than 1, and the organic carbon content in Maantang is more than 2.5 in Ya'an area. The TOC value of Maantang decreases gradually from the southwest of Ya'an area to the north east direction, which indicates that the area far from Longmen Mountain thrust belt decreases gradually. There are many types of organic matter, such as type 鈪，

本文編號：1958733