从烃源岩、储层、盖层等基本地质条件,沥青的地球化学特征,以及地层后期抬升的低温年代学等方面系统解剖了四川盆地东南缘习水吼滩志留系古油藏的成藏特征。习水吼滩古油藏的主要储层是下志留统石牛栏组亮晶生屑灰岩,储层沥青主要分布在生物碎屑颗粒之间和粒内溶孔中,该储层沥青来自志留系自身的烃源岩。志留系源岩生成于还原沉积环境中,有机质主要来自于低等水生生物。志留系储层中与油气包裹体共生的盐水包裹体均一温度平均为97.2℃,结合研究区地层沉积埋藏史,可以确定油气充注的时间大约为距今200Ma。邻近志留系古油藏的下奥陶统湄潭组粉砂岩样品的磷灰石裂变径迹表明,研究区在距今29Ma左右隆升到退火带之内,距今4.5Ma之后经受了加速隆升,约有2100～2450m厚的地层受到剥蚀,最终造成了古油藏的破坏。

<p>The forming characteristics of the Silurian destroyed reservoir in the Houtan section in the southeastern margin of Sichuan Basin were studied according to the basic geologic conditions of source rocks, reservoir rocks and cap rocks,as well as the geochemistry characteristics of bitumen and the thermochronology of detritus minerals. The main reservoir rock of the destroyed oil reservoir is sparite with bioclastic. The bitumen distributed in the inter-grain pores of biological detritus and their solution inner-grain pores. The content and distribution of isoprenoid, steranes and terpanes from bitumen in Silurian illustrated that the source rocks were deposited in the reduced environment, and the organic source mainly came from the low-grade hydrobiosm. The stable carbon isotope showed that the bitumen came from source rock of the Silurian. The mean homogenization temperature of saline inclusions coexisting with hydrocarbon inclusions is 97.2℃. Combined with the burial history of the studied area, the hydrocarbon infilling time was determined to be about 200 Ma before present. The fission track age of apatite in the Ordovician Meitan Formation near the destroyed oil reservoir showed that the formation uplifted in anneal zone at about 29 Ma before present and accelerated uplifted at 4.5 Ma before present. The denudation thickness was about 2100&mdash;2450 m in the studied area, which finally destroyed oil reservoir.</p>

基于露头、岩心、钻井及测井等资料，对川东南地区下志留统石牛栏组岩相古地理及生物礁滩发育特征进行了详尽分析。结果表明：①石牛栏组可划分为2个三级层序，每个三级层序下部发育海侵体系域，上部发育高位体系域；②石牛栏组可划分为三角洲、局限台地、台地边缘浅滩、台地边缘生物礁、台地边缘缓坡和陆棚相沉积；在层序格架内，编制岩相古地理图，台地边缘浅滩和生物礁相主要发育在层序SQ1高位体系域和层序SQ2，岩性主要为生物礁灰岩和生屑灰岩；③研究区主要发育3期台地边缘生物礁、滩，第一期为层序SQ1高位体系域，第二期为层序SQ2海侵体系域中下部，第三期为层序SQ2高位体系域中上部，其中第二期发育规模最大；④台地边缘生物礁滩发育主要受海平面升降、古隆起和陆源碎屑物质输入共同控制，海平面升降控制生物礁滩纵向上发育厚度及向台缘迁移。黔中古隆起抬升使海岸线向北迁移，从而迫使生物向北迁移，雪峰古隆起提供的陆源碎屑物质造成生物逃亡或死亡，一定程度上限制了生物礁滩发育。

Based on outcrop， core， drilling and logging data， this paper makes a detailed analysis on the lithofacies palaeogeography and biological reef shoal development characteristics of the Lower Silurian Shiniulan Formation in southeastern Sichuan Basin. The results show that： （1） The Shiniulan Formation can be divided into two third-order sequences， with transgressive system tracts developed in the lower part of each sequence and high-order system tracts developed in the upper part. （2） Shiniulan Formation can be divided into delta， limited platform， platform edge shoal， platform edge reef， platform edge ramp and shelf facies. In the sequence framework， the lithofacies palaeogeography map is compiled. The platform edge shoals and reef facies are mainly developed in the high system tract of sequences SQ1 and SQ2， and the lithology is mainly reef limestone and bioclastic limestone. （3） Three stages of platform margin reefs and shoals were mainly developed. The first stage was the high system tract of sequence SQ1， the second stage was the lower part of transgressive system tract of sequence SQ2， and the third stage was the upper part of transgressive system tract of sequence SQ2. The second stage was the largest. （4） The development of the reef shoal at the edge of the platform is mainly controlled by the sea level rise and fall and the input of terrigenous clastic materials， and the sea level rise and fall controls the longitudinal development thickness and migration to the edge of the platform. The uplift of the paleo-uplift in central Guizhou makes the coastline migrate northward， which forces the organisms to migrate northward. The terrigenous clastic material provided by the Xuefeng paleo-uplift causes the escape or death of organisms， which limits the development of biological reefs to some extent.

通过对野外剖面、钻井资料及地震资料详细分析，明确了川东南地区志留系石牛栏组沉积期为一向北倾斜的大型缓坡，由南向北可分为内缓坡、中缓坡及外缓坡&mdash;陆棚。其中石牛栏组二段中缓坡相带发育，水体清澈，能量较高，发育礁滩相碳酸盐岩沉积。岩性主要为介壳灰岩、珊瑚灰岩及生屑灰岩等，地震上生物礁滩表现为地层增厚、&ldquo;亮点&rdquo;反射等特征，平面上主要沿叙永&mdash;西门1井&mdash;温水&mdash;隆盛2井呈北东向带状分布。元厚&mdash;四面山一带位于生物礁滩主体带，微古地貌较高，极可能发育礁滩相白云岩储层，是石牛栏组油气勘探有利方向。

Analysis on field outcrops, well data and seismic data clarifies that the Silurian Shiniulan Formation in southeastern Sichuan Basin presents as a large north-dipping gentle slope, which can be divided to (from south to north) inner gentle slope, central gentle slope and outer gentle slope-continental shelf. The second member of Shiniulan Formation (Shi 2 Member) contains central gentle slope facies belt, with clean water and high energy, and it is composed of reef-beach carbonate deposits. The lithology is mainly of shell limestone, coral limestone and bioclastic limestone. Reef beach is characterized by thickened strata and &ldquo;bright spot&rdquo; on seismic profile and represents NE-trending ribbon-pattern distribution along the Xuyong-Well Ximen 1-Wenshui-Well Longsheng 2 in plane. The Yuanhou-Simianshan area is located in the main part of reef-beach zone, with high micro-geomorphology, where the reef-beach dolomite reservoirs are probably developed, suggesting as the favorable exploration prospect of the Shiniulan Formation.

晚奥陶世—早志留世川南地区古地貌特征及其对上覆页岩的控制，目前尚无系统认识。通过地球物理解释、年代地层划分对比、页岩等厚图编制及页岩物质组成分析，明确了五峰组—龙马溪组沉积期川南地区古地貌及其对含气页岩的控制。结果表明：①五峰组—龙马溪组沉积时期，川南地区位于乐山—龙女寺古隆起东南斜坡之上，该斜坡为同沉积水下斜坡，由威远地区向东南延伸至泸州地区，延伸距离达85 km，地形坡降0~1 m/km；②乐山—龙女寺古隆起东南斜坡发育三大地形坡折，其将东南斜坡分割成水下高地、水下斜坡、水下平原和水下洼地4个地貌单元；③五峰组—龙马溪组由东南向西北逐层超覆于乐山—龙女寺古隆起东南斜坡之上，斜坡下部位置五峰组和龙马溪组发育完整，而斜坡上部位置由于地势高，故常缺失笔石带LM1?4；④乐山—龙女寺古隆起东南斜坡不同地貌单元页岩的粒度、矿物组成和TOC含量差异，由水下高地至水下洼地，页岩粒度逐渐变细，TOC含量逐渐降低，碳酸盐矿物含量逐渐降低，硅质含量逐渐升高，黏土矿物含量先降低再升高。

The paleogeomorphology and its impact on overlying Wufeng-Longmaxi shale in southern Sichuan Basin of China are still controversial. Based on geophysical interpretation, chronostratigraphic division and transection correlation, shale isometric map compilation, and shale mineral composition analysis, the depositional paleogeomorphology and its impact on the overlying gas-bearing shale were clarified. The results show that: (1) During Late Ordovician and Early Silurian, the southern Sichuan Basin was located on the southeastern slope of the Leshan-Longnüsi paleo-uplift. The paleo-uplift, which was a syn-depositional one and had span distance reaching up to 85 km and topographical gradient ranging from 0 to 1 m/km, extended from Weiyuan area to Luzhou area southeastward. (2) During the depositional period of the Wufeng-Longmaxi shale, there existed three significant slope breaks which divided the southeastern slope into four geomorphological units, namely, sub?aqueous high, subaqueous slope, subaqueous plain, and subaqueous sag. (3) The Wufeng-Longmaxi shale, which onlaps the southeastern slope from southeast to northwest, is wholly developed in subaqueous plain and subaqueous sag but commonly losses the graptolite zones LM1-4 in subaqueous high and subaqueous slope. (4) There exist significant differences in shale grain size, mineral composition, and TOC content of shale upon different geomorphological units. Commonly, from the subaqueous high to the subaqueous sag, the shale grain size gradually becomes finer, the TOC content and carbonate mineral content gradually decrease, the silica content gradually increases, and the clay mineral content first decreases and then increases.

随着油气钻探技术的提高和勘探工作的不断深入,深层油气勘探愈来愈被重视,深层将可能成为未来储量增长的重要接替领域。对中国7000m以下深井的钻探资料和深层油气地质资料分析表明,烃源岩的生烃深度下限范围可能较大,高过熟阶段的烃源岩生烃潜力依然存在。深部各类有效储集体的保存深度下限可能下移,以发育裂缝型储集体为主,油气藏类型主要包括早期成藏-后期深埋型、储层深埋后晚期成藏型和多期充注成藏型。早期成藏可以抑制深埋过程中岩石孔隙的萎缩,埋深大于6000m的油藏以裂缝型储集体占优势,断裂带附近裂缝型储集体更为发育,断裂通常是晚期成藏型油气藏的重要输导通道。断裂带附近油气富集程度较高,油气多期充注作用和强烈充注作用往往能提高油气藏的储量丰度。因此,中国中、西部盆地7000m以下层系成藏条件较好,油气资源潜力可观。

With the development of drilling techniques and oil-gas exploration, deep hydrocarbon exploration has gained more and more attention and may become an important fungible field for rising reserves. Analysis on the data of drilling and oil-gas geology of deep wells over 7 000 m in depth shows that the low limit of depth range for generation of deep hydrocarbon is possibly large, and there still exists the hydrocarbon-generation potential for the high mature source rocks. The low limit of preservation depth for the effective reservoir can shift downward, and the fractured reservoir is predominant. The oil-gas pools mainly include the earlier accumulation-later deep burying pattern, the later accumulation pattern after deeply burying and the multi-stage charging pattern. The earlier accumulation pattern can restrain the shrink of rock porosity during the deep burying process. The fractured reservoir is predominant and more developed near the fault belts, when the burial depth is more than 6 000 m. Faults connected with the deep source rocks are usually the important migration pathways for the later oil accumulation. The hydrocarbon enrichment degree near the fault belts is very high. The multi-stage hydrocarbon charging and strong charging processes can often improve the reserve abundance. The hydrocarbon resource in the strata beyond 7 000 m in depth is of considerable potential in the basins in central and western China.