地质学报Issue(11)：2119-2130,12.
陕北盐盆奥陶系马家沟组沉积相特征与沉积演化
Sedimentary Facies and Evolution of the Ordovician Majiagou Formation in Salt Basin of Northern Shaanxi
摘要
Abstract
Based on 8 wells(e.g.Zhenjia 1 well,etc)in the Northern Shaanxi salt basin,cores observation and well logging interpretation,identification of microscopic flakes,combined with regional tectonic data and previons research achievements,the Ordovician majiagou Formation rock types,sedimentary facies and sequence stratigraphy were studied.The rock types are mainly carbonates and evaporites,clastic rock and other sedimentary rocks less development.The main development of carbonate platform facies can be further divided into two subfacies:open platform and restricted evaporate platform.Open platform can identify limemud mound microfacie and the microfacies contain dolomitic flat,salt lake,gypsum lake. Sedimentary evolution shows that the salt basins in northern Shaanxi had experienced three timestransgressive-regressive cycles from Ma1 to Ma6 period.Sedimentary evolution created good salt palaeogeographic environment for Shaanxi salt basin and sylvite forming,and the sea-water supplied enough potassium material in the transgression.Inheritance of salt basins formed in the regressive period around the uplift at favorable evaporation low latitudes drought climate environment are was very favorable for the formation of potassium rock.Shaanxi salt basin showed the tectonic pattern of “two depressions and one lifting”,for west salt sags,middle uplift,east salt sags which are NNE-striking from west to east. west salt sags are made of “west 1 salt sags”,“west 2 salt sags”and “west 3 salt sags”from north to south;East salt sags were made of”east 1 salt sage”in the north and ”east 2 salt sage”in the south.The five salt sags with the thicknesses of more than 150 meters in this region are the best locations for potassium salt formation in Shaanxi salt basin,suggestion a priority targets for potash exploratory well deployment in the favorable area.关键词
陕北盐盆/马家沟组/沉积/灰泥丘Key words
North Shaanxi Salt Basin/Majiagou Formation/sedimentary/limemud mound引用本文复制引用
施立志,王卓卓,张永生,苏奎,邢恩袁,桂宝玲..陕北盐盆奥陶系马家沟组沉积相特征与沉积演化[J].地质学报,2015,(11):2119-2130,12.基金项目
本文由国家重大基础研究计划“973”课题“鄂尔多斯奥陶纪古陆表海盆成钾条件、机理和后期演化”（编号2011CB403001）和中国地质调查局地质调查工作项目“陕北奥陶纪盐盆地钾盐资源调查评价”（编号1212011085516）和联合资助。 （）
