Strontium Isotope Characteristics And The Origin Of Salt Deposits Of Salt Deposits In West China

Potash is virtually inescapable in industry and agriculture.China is seriously deficient in potash resources,there is an urgent need to develop new potash resources.It is very important to study metallogenic model of evaporites.Learning the material source of evaporates helps with the study of metallogenic model.Strontium isotope is a well tracer for studying the material source of evaporite.In this article,we have selected 3 salt-bearing basins which are Lanpingsimao basin,Kuqa basin and Qaidam basin to study the material source of evaporates and brine.We analyzed the strontium isotope geochemical of evaporates and brine in Lanpingsimao basin.Results show that the strontium isotope ratios of shallow salt varied from 0.709610 to 0.709869 and the strontium isotope ratios of deep salt is 0.707666,consistent with the strontium isotope ratios of seawater.Indicating that the brine of the salt mineral deposits in Simao basin were mostly from seawater.Shallow salt show higher strontium isotope ratios than seawater.This indicates that the salt might have been effected by the continental water.After adjustment,the strontium isotope of deep salt is very close to the seawater in Middle Jurassic.This indicates that the salt might come from Jurassic strata.We analyzed the Strontium isotope geochemical of evaporates in Kuqa basin.Results show that the strontium isotope ratios of salt is different between Paleogene and Miocene.Strontium isotope ratios of Paleogene salt varied from 0.708718-0.709326,consistent with the strontium isotope ratios of seawater.While strontium isotope ratios of Miocene salt varied from 0.709909-0.710868,higher than seawater and lower than the continental water.This indicates that the material source of salt is both seawater and continental water.We analyzed the Strontium isotope geochemical of brine in Qaidam basin.Results show that the strontium isotope ratios of brine varied from 0.711307-0.711979,higher than seawater and lower than some salt lakes.This indicates that the mainly materialsource of brine is continental water and brine might have been effecter by deep water from mantle.