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中泥盆统由西南部Pine Point延伸至不列颠哥伦比亚东北山麓之下的Presqu′ile障壁岛的中、晚期粗晶交代白云石伴随着异形白云石胶结物形成了一个广泛分布的成岩相带,分布在加拿大本土的西北部和不列颠哥伦比亚东北地区以及在Pine Point地区的密西西比型矿床的围岩层中,这些白云石构成了烃类储层,反之则为致密灰岩。粗晶交代白云石和异形白云石胶结物是在埋藏过程中形成的,因为它们交代了块状亮晶方解石胶结物,并且连续穿过Watt山组不整合面、晚期缝合线和早期交代白云石以及叠加在硫化物的结晶之后,交代和异形白云石的δ~(18)O值沿Presqu′ile障壁岛上倾方向向东增加,在不列颠哥伦比亚东北部的地下深处为—16‰PDB,在Pine Point为—7‰PDB,而异形白云石流体包裹体的相应均一温度由178℃变化到92℃。粗晶和异形白云石的~(87)Sr/~(86)Sr值沿Presgu′ile障壁岛向东由不列颠哥伦比亚东北部地下的0.7106降低到Pine Point地区的0.7081,这些地球化学趋势表明了热液,放射性成因的白云石化流体向东沿Presqu′ile障壁岛上倾方向在盆地范围内迁移的可能性。如此大规模流体运动很可能与加拿大西部沉积盆地的构造挤压和沉积负载有关,这种运动至少有两期:在晚泥盆和早石炭世时期的早期埋藏期间和晚休罗和早第三世时期?
The middle and late coarse-grained metamorphic dolomites, extending from Pine Point in the southwestern part of the country to the Presqu’ile barrier island in the northeastern British Columbia, form a widely distributed diagenetic facies belt along with heterogeneous dolomite cements These dolomites form hydrocarbon reservoirs in the northwest of Canada and the northeastern British Columbia and the Mississippi deposits in the Pine Point area, and are, in contrast, tight limestone. Coarse-grained dolomite and alien dolomite cements were formed during burial because they account for massive luminescent calcite cements and continuously pass through the Watt Hill Formation unconformity, late suture and early dolomite and After superposition of sulfide crystals, δ 18 O values of metasomatic and dolomitic dolostones increase eastward along the updip direction of the Presqu’ile barrier island to -16 ‰ PDB deep in the northeastern British Columbia, Pine Point was -7 ‰ PDB, while the corresponding homogenization temperature of aliened dolomite fluid inclusions varied from 178 ℃ to 92 ℃. The ~ (87) Sr / ~ (86) Sr values of coarse and irregular dolomites decrease eastward along the Presgu’ile barrier island from 0.7106 in the northeastern British Columbia to 0.7081 in the Pine Point region, indicating that these geochemical trends Liquid and radiogenic dolomitization fluids migrate eastward along the updip direction of the Presqu’ile barrier island within the basin. Such large-scale fluid movements are likely to be associated with tectonic compression and sedimentation loads in the sedimentary basins of Western Canada at least for two periods: during the early burial period of the Late Devonian and Early Carboniferous periods and late Huluo and early third World period?