桩西、埕岛地区古潜山储层受大气水影响的地球化学证据

Geochemical Evidence of Influence upon the Reservoir of Buried Hill by Meteoric Water in the Regions of Zhuangxi and Chengdao

通过对桩西、埕岛地区下古生界碳酸盐岩的地球化学特征研究,发现在岩石的各种结构组分中,岩石的洞或脉中的方解石充填物与基质在同位素特征和元素特征上存在较大的差异,即洞或脉中的方解石充填物具有显著较高的87Sr/86Sr比值,较低的δ13C、δ18O值和较高的Mn含量等特征。这些特征进一步说明了该区古岩溶储层的发育与其上覆的加里东不整合面有关,其所经历的重要岩溶作用为大气水成岩作用,发生的时间为表生成岩阶段。

We study the geochemical characteristic of carbonate rock of lower Palaeozoic burial hills in the regions of Zhuangxi and Chengdao and find that the calcite fillings in cave or vein have high value of ^(87)Sr/^(86) Sr, low value of δ^(13)C and δ^(18) O and high Mn content among of different structural components. The evidence strongly suggests that it has been exposed to be dissolved by meteoric water on supergene diagenetic stage.