摘要
塔中Ⅰ号断裂坡折带的区域构造-沉积演化为塔中地区上奥陶统礁滩体的发育提供了基本的沉积背景。经历了加里东期、早海西期及晚海西期三期构造运动,形成三期三种级次的断裂:一级断裂规模较大,主要形成于加里东期,走向北西—南东向;早海西期形成二级断裂,规模相对较小,走向与一级断裂近于垂直;晚海西期形成的三级断裂,规模更小,走向则近于一级断裂。这三期构造运动的应力场方向是来回变化的,强度则逐渐减弱。这种构造运动特征引起了礁滩体发育环境的反复变化,因而形成了多期礁滩体,它们在垂向上出现叠置的现象。古地貌形态对礁滩体的发育具有控制意义,礁滩体主要发育在古地貌高点上,并在横向上形成带状分布。在研究区,以塔中Ⅰ号断裂坡折带中部的礁滩体最为发育,并呈现出多期发育的特点。
The Tazhong Ⅰ Fault Slope-Break Belt and its adjacent area constitutes the basic tectonic framework of Tazhong Lower Arch,where the regional tectonic-sedimentary evolution provides a basic sedimentary background for the Upper Ordovician reef-shoal development in this area.There were three periods of tectonic movements including the Caledonian,the Early Hercynian and the Late Hercynian movements in Tazhong and consequently different graded fractures formed during each period.The 1st-grade fractures formed during the Caledonian period and usually are NW-SE strikes.The 2nd-grade fractures that are smaller than the 1st ones in scale formed during the Early Hercynian and exhibit an almost vertical strike to the Caledonian fractures.The 3rd-grade fractures which developed during the Late Hercynian show a nearly parallel strike to the 1st-grade fractures,The stress of these three periods of tectonic movement changed frequently in direction and the stress gradually weakened in intensity.The development environment of reef-shoals varies repeatedly,which makes phases of reef-shoals form and superimpose in vertical.The paleo-geomorphology controls the development of reef-shoals,which main develop on morphologic rises and is characterized of zonal distribution in lateral.
出处
《海相油气地质》
北大核心
2012年第4期16-22,共7页
Marine Origin Petroleum Geology
关键词
塔中Ⅰ号断裂带
碳酸盐岩储层
构造-沉积背景
控制作用
古地貌特征
塔中地区
Reef-shoal
Carbonate reservoir
Structural and sedimentary setting
Control effect
Paleogeomorphology
Fault slope-break belt
Tazhong area
Tarim Basin