山西省柳林奥陶系古岩溶顶部方解石充填物  

CALCITE FILL ON THE TOP OF ORDOVICIAN PALEOKARST IN LIULIN, SHANXI

作　　者：王宝清[1] 

机构地区：[1]西安石油学院石油天然气地质研究所

出　　处：《地质论评》1995年第5期473-479,T001,共8页Geological Review

摘　　要：山西省柳林马五_1地层顶部古岩溶发育,其孔、洞、缝中充填着大量的粒状、镶嵌状淡水方解石。根据方解石充填物的碳氧稳定同位素分布特征,包裹体的均一温度和盐度,阴极发光特征,可以把方解石充填物分为早期充填物和晚期充填物。早期充填物的δ^(13)C值—7.710‰—0.575‰,平均为—3.722‰;δ^(18)O值—9.753‰至—7.124‰,平均为—8.766‰;δ^(13)C和δ^(18)O值与泥晶方解石和白云石有相似的分布范围。晚期充填物的δ^(13)C值为—16.595‰至—5.699‰,平均—9.374‰;δ^(18)O值—18.953‰至—12.678‰,平均—15.108‰;δ^(13)C和δ^(18)O值较泥晶方解石和白云石明显偏低。方解石充填物包裹体的均一温度为76—239℃,盐度为0.8％—9.0％。早期方解石充填物包裹体的均一温度和盐度较低,分别小于95℃和2％。早期方解石充填物有较强的阴极发光,晚期方解石充填物无阴极发光。阴极发光强度是Mn^(2+),Pb^(2+),Cu^(2+),Zn^(2+),Cr^(3+)等激活剂和Fe^(2+),Ni^(2+),Co^(2+)等猝灭剂的函数。Paleokarst is well developed in the uppermost first submember of the Ordovician Majiagou Formation (M51) in Liulin, Shanxi. The pores, cavities and fractures are filled with abundant fresh-water granular and mosaic calcite. In the light of the carbon and oxygen isotopic composition , homogenization temperatures and salinity of fluid inclusions and characteristics of cathodolu-minescence, the calcite fills are frouped into the early-stage fill and the late-stage fill.The values of δ13C and δ18O of the early-stage calcite fill, which are similar to those of micrite and dolomite, range from -7. 710‰ to 0. 575‰ and from -9. 753‰ to -7. 124‰ with means of -3. 722% and -8. 766% respectively. The values of δ13C and /18O of the late-stage calcite fill, which are obviously lower than those of micrite and dolomite, range from -16. 595‰ to -5. 699‰ and from -18. 953‰ to -12. 678‰ with means of -9. 374‰ and -15. 108‰ respectively. The homogenization temperatures of fluid inclusions range from 76-239‰ and the salinity of fluid inclusions range from 0. 8%-9. 0% . The homogenization temperatures and salinity of fluid inclusions in the early-stage calcite fill, which are lower than those in late-stage calcite fill,are less than 95℃ and 2% respectively. The early-stage calcite fill has strong cathodo-luminescence, while the late-stage one has no luminescence. Luminescence intensity is the function of activators or sensitizers such as Mn2+ , Pb2+ , Cu2+ , Zn2+ and Cr3+ and quenchers such as Fe2+, Ni2+and Co2+.

关 键 词：方解石充填物 古岩溶 奥陶系 

分 类 号：P534.42[天文地球—古生物学与地层学]