埕北30下古生界潜山古岩溶发育特征

依据埕岛地区的岩心、录井和测井资料,对该区下古生界各种古岩溶作用进行系统的对比,研究了各期次古岩溶的发育模式、特征、控制因素以及识别标志.将埕北30潜山下古生界碳酸盐岩地层的古岩溶作用分为6期:第1期(加里东早期),主要为地表淡水岩溶;第2期(加里东中期—海西期),主要为暴露期表生淡水岩溶和末期的海水岩溶;第3期(印支期),主要为剥蚀区的暴露表生淡水岩溶作用和覆盖区的埋藏区淡水渗滤岩溶;第4期(燕山早期),主要有地表淡水岩溶、埋藏淡水渗滤岩溶;第5期(燕山晚期—喜山早期),主要为深埋型地下热液岩溶;第6期(喜山晚期),主要为地下热液和埋藏有机溶蚀型岩溶.

Palaeokarst development characteristics of Lower Paleozoic buried hill in Chengbei 30

Base on the information from the drill core,well logging,each kind of palaeokarst function of Lower Paleozoic buried hill is compared in Chengdao area.The developed pattern,characteristic,controlling factor and identification marks of the various stages of palaeokarst are studied.There are six stages of carbonate rock palaeokarst function of Lower Paleozoic buried hill in Chengbei 30.The first stage(early Caledonian),mainly is freshwater karst of land surface.In the second stage(middle Caledonian to Hercynian),the main karst growth patterns are exposed as hypergene freshwater karst and last stage seawater karst.In the third stage(Indosinian),the main karst growth patterns are exposed as hypergene freshwater karst function in disintegration area and buried freshwater infiltration karst in the cover area.In the fourth stage(early Yanshanian) the main karst growth patterns are the surface freshwater karst and the buried freshwater infiltration karst.The fifth stage(late Yanshanian to early Himalayan),the main karst growth pattern is deeply buried underground as hydrothermal karst.In the sixth stage(late Himalayan),the main karst growth patterns are underground hydrothermal and buried organic corrosion karst.