CAJ | 학술논문

陕北奥陶纪盐盆位于鄂尔多斯盆地伊陕斜坡东部。研究表明：马五6亚期，盐盆存在“两坳一隆”的构造格局，即东、西部盐坳和中部隆起，东、西部盐坳在钾矿化情况、溴氯系数反映的水体咸化趋势方面初步显示了陕北盐盆东、西部沉积环境的差异。本文通过东、西部盐坳典型钻井马五6层位沉积学分析，揭示了马五6时期东、西部盐坳在水体深度变化、浓缩趋势、含钾量、淡化层段厚度、陆源物质输入方面均存在差异。其中，西部盐坳受海水影响大，水体变浅且持续淡化，泥质分布反映陆源物质贡献少，对钾盐的沉积与保存均十分不利。而东部盐坳受海水影响小，与西部盐坳水体联通性差，在马五6时期环境更为封闭，具体表现为淡化夹层分布数量少、厚度薄的特征；水体持续变深并浓缩咸化；泥质夹层较多，反映了相较于西部，陆源物质对其影响更大，上述特点为钾盐沉积提供了有利的地球化学条件及可容空间。东、西部盐坳沉积环境对比表明东部盐坳对成钾更为有利。
협북오도기염분위우악이다사분지이협사파동부。연구표명：마오6아기，염분존재“량요일륭”적구조격국，즉동、서부염요화중부륭기，동、서부염요재갑광화정황、추록계수반영적수체함화추세방면초보현시료협북염분동、서부침적배경적차이。본문통과동、서부염요전형찬정마오6층위침적학분석，게시료마오6시기동、서부염요재수체심도변화、농축추세、함갑량、담화층단후도、륙원물질수입방면균존재차이。기중，서부염요수해수영향대，수체변천차지속담화，니질분포반영륙원물질공헌소，대갑염적침적여보존균십분불리。이동부염요수해수영향소，여서부염요수체련통성차，재마오6시기배경경위봉폐，구체표현위담화협층분포수량소、후도박적특정；수체지속변심병농축함화；니질협층교다，반영료상교우서부，륙원물질대기영향경대，상술특점위갑염침적제공료유리적지구화학조건급가용공간。동、서부염요침적배경대비표명동부염요대성갑경위유리。
The northern Shaanxi salt basin is located in the east of the Yishan slope in the Ordos Basin.The study indicates that the salt basin was septarated into the two depressions and the one rise,including the east depression,the west depression and the middle rise.The potassium mineralized characters and the value of Br/Cl×103 indicating the tendency of saline reflect the difference of the sediment environment in the east and west salt depressions.The sedimentological analysis of the M65 subsection from the typical drilling well reveals the difference in the change of water depth,the tendency of concentrating,the potassium showing,the thickness of desalination layer,the input of the terrigenous material.Among them,the west salt depression was affected by the sea water greatly;the water was desalination continuously;the mud distribution reflects the low contribution of the terrigenous material.It is bad for the potash depositing and preservation.The east salt depression was affected by the sea water weakly,and has the bad connectivity with the west salt depression,which leads to the closed sediment circumstance in the M65 stage,showing the small thickness and quantity of the desalination interlayer;the water became deep and concentrating continuously;the mud interlayer was rich,reflecting the contribution of the terrigenous material was larger in the east than in the west.The above characters provide the advantageous geochemistry condition and accommodation.It is conducive for the potash depositing and preservation.