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臼齿构造碳酸盐岩是全球各大陆中、新元古代时期普遍发育的、具有特殊成因意义的碳酸盐岩类型,到目前为止,已在全球20多个地区近50多个中、新元古代地层剖面中被发现。百余年来,有关MT的研究越来越深入,进展显著。从前期和前人较少关注的有关MT与宿主岩石的关系,尤其是从MT与宿主岩石地球化学特征的关系及其所揭示的地质意义出发,通过薄片、电子探针、背散射、阴极发光等测试手段及C、O、Sr同位素的系统测试,对辽东地区新元古代南关岭组、营城子组及兴民村组MT及其宿主岩石的成分、结构、微观组构等特征进行了深入研究。研究证明,MT是原生或早期成岩的产物,由原生海水埋藏成岩和海水直接成岩形成;MT与宿主岩石具有相似的地球化学特征,具有同生或准同生的特点,形成于温暖的正常海水环境,并于Sturtian冰期前终止发育。锶、碳同位素同全球中、新元古代碳-锶同位素理论曲线类比表明,大连新元古代南关岭组和营城子组的形成时限为760～950 Ma,兴民村组形成时限为720～800 Ma,与胶辽徐淮地区新古代地层具有良好可对比性。
Molar structure of carbonate rock is a type of carbonate rock that has been widely developed in all continents during the Neoproterozoic period and has special genetic significance. So far, nearly 50 carbonate-based rocks in more than 20 regions in the world Ancient strata profile was found. Over the past 100 years, the research on MT has been more and more in-depth and has made remarkable progress. The relationship between MT and host rock, which was less concerned by the previous and previous generations, especially from the relationship between MT and host rock geochemistry and the geological significance of the host rock revealed by thin films, electron probe, backscattering, cathodoluminescence Such as the test methods and C, O and Sr isotopes, the composition, structure and microstructure of MT and its host rock in the Neoproterozoic Nanguanling Formation, Yingchengzi Formation and Xingmin Village in the Liaodong area were studied In-depth study. The study shows that MT is a product of primary or early diagenesis, which is formed by the primary diagenesis of seawater and the direct diagenesis of seawater. MT has the similar geochemical characteristics with the host rock and has the characteristics of cohabitation or quasigenesis, forming in warm normal seawater Environment and stopped development before the Sturtian ice age. The analogies of strontium and carbon isotopes to the global and Neoproterozoic carbon-strontium isotope curves indicate that the formation time of the Neogene Archean Nanguanling Formation and Yingchengzi Formation in Dalian is between 760-950 Ma and that of the Xingmincun Formation is 720 ~ 800 Ma, with the Jiaoliao Xuhuai area of the ancient palaeontology has a good contrast.