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世界上菱镁矿矿床可大体分为三类:与超基性岩有关的菱镁矿、大型层状菱镁矿以及现代蒸发沉积条件下形成的菱镁矿。一般来说,蒸发环境下的富镁海水可能会促进菱镁矿的形成,例如在现代盐湖、萨布哈等环境下菱镁矿能够直接从海水中沉淀,但仅为薄层。与此形成鲜明对比的是,世界上大型层状菱镁矿主要发育在前寒武的碳酸盐岩地层中。此外,热液交代或埋藏成岩过程也可形成菱镁矿。此过程主要为富镁流体(淋滤周围白云岩或其他富镁岩石)交代沉积的白云石形成菱镁矿。总体而言,大型层状菱镁矿的
Magnesite deposits in the world can be broadly divided into three categories: magnesite associated with ultramafic rocks, large-scale layered magnesite, and magnesite formed under modern evaporative deposition. In general, magnesium-rich seawater under evaporative conditions may promote the formation of magnesite. For example, in modern salt lakes and Sabuha, magnesite can precipitate directly from seawater but only in thin layers. In stark contrast, the large-scale stratigraphic magnesite in the world mainly develops in pre-Cambrian carbonate formations. In addition, hydrothermal alteration or burial diagenesis can also form magnesite. This process is dominated by dolomite-forming magnesite deposited as a magnesian-rich fluid (dolomite or other magnesium-rich rock leached around). In general, large stratiform magnesite