2026-10-14T14:23:49Z https://www.scidb.cn/oai

10.57760/sciencedb.36820 2026-05-14T10:13:19Z

2026-05-14 Genetic Mechanism of the Late Cretaceous Potassium Salt Deposit on the Khorat Plateau: Insights from the H-O-Cl Isotopic Constraints of Evaporite Minerals doi:10.57760/sciencedb.36820 en Potassium salt is a critical mineral resource for safeguarding the supply of agricultural potash fertilizer and human food security. As an important metallogenic area of Late Cretaceous potassium salt deposits worldwide, the Khorat Plateau provides an ideal window for investigating the metallogenic regularities of potassium salt deposits. Stable isotopes are powerful tools for elucidating the genetic mechanisms of evaporite deposits. In this study, hydrogen(H) and oxygen (O) isotopes of carnallite, as well as chloride (Cl) isotopes of halite and sylvite, were analyzed from core samples of the ZK004 borehole in the Longhu mining district of the Sakon Nakhon Basin in the Khorat Plateau. The analysis results reveal that the carnallite from the depth between 83.50 m and 140.00 m exhibits δD values ranging from -52.7‰ to -37.3‰ (mean: -45.5‰) and δ18O values ranging from -8.3‰ to +0.6‰ (mean: -1.5‰). Halite and sylvite samples from depths between 71.85 m and 83.85 m display δ37Cl values ranging from -0.31‰ to +0.67‰ (mean: +0.20‰) and from -0.87‰ to +0.75‰ (mean: +0.03‰), respectively. The H-O isotopic signatures indicate that the carnallite was derived from the Late Cretaceous seawater that underwent extreme evaporation and subsequent mixing with meteoric water. Meanwhile, Cl isotopic data indicate a marine depositional environment for the Late Cretaceous potassium deposit. The sylvite metasomatism may be derived from the structural movement, and the non-marine inputs also contributed to the deposition of the potassium salt deposit. Combined with the previous studies, the metallogenetic stages of the potassium salt deposit in the Khorat Plateau have been divided into four stages: 1) original evaporation and deposition stage; 2) carnallitite metasomatic leaching stage; 3) structural metasomatic leaching stage; and 4) final deposition stage. These isotopic constraints provide new insights into the formation of the Late Cretaceous potassium salt deposit on the Khorat Plateau.  Khorat Plateau; Potassium salt deposit; Hydrogen-Oxygen isotopes; Chloride isotopes; Genetic mechanism Dengxian Zhu Pin Gao Xiaochen Ma Xiying Zhang Zhanjie Qin Guocheng Shi Xiaolong Yuan Weiliang Miao Yongqiang Yu Yong Wang Dejin Yan PUBLIC https://creativecommons.org/licenses/by-nc-sa/4.0/ dataset Science Data Bank