【作者】 吴程赟；

【导师】 顾雪祥；

【作者基本信息】 中国地质大学(北京) ， 矿产普查与勘探， 2012， 硕士

【摘要】 扬子地台西南缘的黔西南地区，不仅是我国卡林型金矿床的重要产区，也是我国南方油气勘探的重要战略区块。区内卡林型金矿床主要赋存于二叠系、三叠系地层，受背斜或断裂构造的控制。以水银洞、烂泥沟、丫他三个典型卡林型金矿床为例，水银洞金矿床主要赋存于上二叠统龙潭组生物碎屑灰岩、粉砂岩中，矿体受区域性控矿构造灰家堡背斜及其内部同沉积断裂的控制；烂泥沟和丫他金矿床主要赋存于中三叠统边阳组、新苑组的粉砂岩、泥质岩中，矿体产出受断裂构造的控制。矿床中围岩蚀变主要包括黄铁矿化、毒砂化、硅化、碳酸盐化、粘土化，其中硅化和黄铁矿化与成矿关系紧密。黔西南地区的古油藏与卡林型金矿床受相同构造单元的控制，通常产于盆地边缘和孤立台地相带，与金矿化显示密切的空间关系。古油藏均赋存于上二叠统吴家坪组生物礁灰岩中，礁体的储集空间主要包括孔隙、裂缝和溶洞。以白层、赖子山、板街古油藏为例，固体沥青产出于礁灰岩生物格架孔隙、方解石晶洞、晶间孔隙及溶蚀隙、构造缝隙及溶蚀缝中，呈颗粒状、油珠状、浸染状或块状产出，产出形态受孔隙形态的控制。沥青呈现镶嵌结构、球状结构、复合球状结构、波状结构，为高成熟度焦沥青。有机岩相学观察显示，烂泥沟、丫他、水银洞卡林型金矿床中的有机质主要包括干酪根及固体沥青两部分。干酪根包括藻类体、镜质体、丝质体等组分，为原地有机质成岩作用产物；固体沥青主要产出于矿石内，与矿化关系密切，产出形态受孔隙、构造裂隙控制，为异地运移来的原油裂解产物。固体沥青与矿石矿物的共生关系表明，沥青的形成时间与金矿化近于同时。有机地球化学测试表明，古油藏沥青与金矿床赋矿地层中的有机质具显著不同的有机地球化学特征，两者无亲缘关系。但矿床内沥青及部分矿石氯仿抽提物的有机地球化学特征与古油藏沥青一致，表明金矿床内固体沥青及部分矿石内有机质与古油藏沥青具相同的来源。黔西南地区卡林型金矿床与二叠系古油藏在空间上密切共生、在成矿和成藏流体活动时限上基本一致、在成因上一脉相承，指示两者可能为盆地流体在大规模侧向运移过程中成矿-成藏作用的产物。更多还原

【Abstract】 SouthEWst GuiZhou Province is tectonically located at the south edge ofYangtse Craton. It is not only a major production area of Carlin-type gold deposits inChina, but also an important district for oil-exploration in South China. Carlin-typegold deposits in this area are mostly hosted by Permian or Triassic strata, andstructurally controlled by anticlines or fractures. Taking Shuiyindong, Lannigou, Yatathree typical Carlin-type gold deposits for example, Shuiyindong gold deposit ishosted by bioclastic limestone and siltstone of Permian Longtan Formation, andorebodies are controlled by Huijiabao Anticline and syndepositional faults; Lannigouand Yata gold deposits are hosted by siltstone and mudstone in Triassic Bianyang andXinyuan Formation, orebodies are controlled by regionally fracture system. Wallrocka lteration in these deposits includes pyritization, arsenopyritization, silification,carbonatization, siallitization, and silification and pyritization show closerelatioSNhip with gold mineralization.Paleo-oil reserves generally restricted to the same tectonic units as the golddeposits, commonly at the basinal margiSN and within the intrabasinal isolatedplatforms or bioherms, and show close spactial relatioSNhip with gold mineralization.Reservoir rocks are mostly biohermal limestones of Perimian Wujiaping Formationwith EWll-developped fractures and karst caves. Taking Baiceng, Laizishan, Banjiepeleo-oil reservoirs for examples, solid bitumeSN commonly fills in reef-buildingorganism’s framework, karst caves and fractures of biohermal limestones, with itsshape restricted to the open space. BitumeSN have structures which indicating highmaturity, such as mosaic structure, spheroid structure, and wavy structure.Organic petrographic observation indicates that the organic matter in Carlin-typegold deposit can be devided into two categories, including kerogeSN and bitumeSN.KerogeSN are mainly alginite, vitrinite and fusinite, which are diagenesis products ofindigenous organic matter. Solid bitumen is commonly hosted by mineralized rocks,filling fractures and open spaces, indicates a high maturity product of migro-bitumen.Paragenesis relatioSNhip betEWen minerals and bitumen shows that bitumen areformed almostly in the same period of gold mineralization.Organic geochemistry testament shows that bitumeSN in paleo-oil reservoirsand organic matters in the hostrocks of Carlin-type gold deposits has differentcharacters, there is no proof that source rocks for bitumeSN in the paleo-oil reservoirs are from the same sedimentary strata which hosted gold mineralization in this area.But chloroform extractioSN of bitumen and some ores in gold deposits shows thesame pattern with bitumeSN in paleo-oil reservoirs, indicates that solid bitumeSN ingold deposits and paleo-oil reservoirs has the same source, probably are the productsof the same fluid system. Carlin-type gold deposits and paleo-oil reservoirs inSouthEWst Guizhou Province shows close spactial relatioSNhip, and close timingbetEWen gold mineralization and reservoir-formation, indicates that possibally theyare different products of the same basinal-fluid system in this region.更多还原