CAJ | 학술논문

新疆库车前陆坳陷新生代地层发育巨厚的蒸发岩沉积.本文通过对库车坳陷内11口钻井的盐岩样品进行锶同位素地球化学特征的分析，进一步研究坳陷内盐岩地层的成盐物质来源.测试结果表明，库车坳陷盐岩的锶同位素在0.708718~0.710868之间，不同时代的盐岩沉积的锶同位素组成明显不同.古近纪盐岩的锶同位素较低，大多在0.7093左右，与海水的锶同位素值接近，表明物质来源主要是海水.中新世盐岩的锶同位素多在0.7100以上，锶同位素组成介于海水和陆源盐湖之间，表明是海水和陆源水的混合的结果.推断库车坳陷古近纪早期受到海侵，渐新世海侵结束后，残余海水在中新世形成泻湖，与陆源卤水相混合并沉积成盐.
신강고차전륙요함신생대지층발육거후적증발암침적.본문통과대고차요함내11구찬정적염암양품진행송동위소지구화학특정적분석，진일보연구요함내염암지층적성염물질래원.측시결과표명，고차요함염암적송동위소재0.708718~0.710868지간，불동시대적염암침적적송동위소조성명현불동.고근기염암적송동위소교저，대다재0.7093좌우，여해수적송동위소치접근，표명물질래원주요시해수.중신세염암적송동위소다재0.7100이상，송동위소조성개우해수화륙원염호지간，표명시해수화륙원수적혼합적결과.추단고차요함고근기조기수도해침，점신세해침결속후，잔여해수재중신세형성사호，여륙원서수상혼합병침적성염.
Great thickness of evaporite strata were formed in Xinjiang Kuqa foreland depression during Cenozoic period.In this paper,we analyzed the strontium isotope geochemistry of salt which were collected from eleven drillings in Kuqa depression to provide insight into the origin of the deposit’s brine.Results show that the 87 Sr/86 Sr ratios of the samples from Kuqa depression varied from 0.708718 to 0.710868.There are different strontium isotope between two evaporite strata.The strontium isotopic ratios of Paleogene salt which are in the lower level,are mostly around 0.7093,consistent with the 87 Sr/86 Sr ratios of seawater,indicating that the brine of the salt deposits were mostly from seawater in Kuqa depression.Miocene salt samples show the 87 Sr/86 Sr ratios higher than seawater and lower than the continental water.This indicates that the brine of the Miocene salt deposits are from both seawater and continental water.We concluded that the Kuqa depression were suffered transgression in early Paleogene.The transgression ended in Oligocene.Residual seawater which formed lagoon in Miocene mixed with continental water to deposit into salt.