东秦岭—大别造山带南侧加里东期古隆起特征及油气地质意义

加里东期在东秦岭—大别造山带南侧江汉平原地区存在一个继承性古隆起,前人所称的"鄂中古陆"是其具体的表现."鄂中古陆"在时间上存在于晚震旦世末—中寒武世,在平面上主要展布于江汉平原北部神农架—保康—荆门—京山及以北地区,向北东越过现今的青峰—襄樊—广济断裂带,其后古隆起继承性发展,控制了中扬子地区加里东期北高南低的古地貌特征.加里东期古构造可划分为东秦岭堑垒带、中扬子北部隆起带、中扬子中部斜坡带、中扬子南部坳陷带等4个单元.东秦岭—大别造山带南侧加里东期古隆起对油气成藏条件具有明显的控制作用,古隆起是早期液态烃运移聚集的有利指向区,是目前江汉平原地区震旦系—下古生界油气勘探突破的有利地区. 

Petroleum geological significance and characteristics of Caledonian paleouplift in the southern margin of east Qinling and Dabie orogenic belt

There is a inherited paleouplift in the Jianghan Plain area of the southern margin of East Qinling and Dabie Orogenic Belt during Caledonian period.The authors believe that the Ezhong(Central Hubei Province)paleocontinent named by predecessors is its concrete expression.It exists in Late Sinian-Middle Cambrian in time domain and mainly distributed in Shennongjia-Baokang-Jingmen-Jingshan of the northern Jianghan Plain area and its north on the plane.The Ezhong paleocontinent passes over the Qingfeng-Xiangfan-Guangji fault zone.Subsequently,successive development of paleouplift has controlled paleogeomorphic forms of higher in the north and lower in the south during Caledonian period in the middle Yangtze region.The results showed that the Caledonian paleo-tectonic could be divided into four different structural units(the graben-horst belt of the East Qinling;the northern uplift belt of the middle Yangtze;the middle slope belt of the middle Yangtze;the southern depression belt of the middle Yangtze).The Caledonian paleouplift was evident in control of Sinian-Lower Paleozoic reservoir conditions in the southern margin of East Qinling and Dabie Orogenic Belt.The Caledonian paleouplift was a favorable destination for the migration and accumulation of early liquid hydrocarbon,which is important target for petroleum exploration breakthrough of Sinian-Lower Paleozoic reservoirs in Jianghan Plain.