现代盐湖沉积与岩盐析出模拟的相似性及其对成盐模式的启示

盐类析出模拟实验有助于增进对成盐模式的理解，但运用正演模拟进行类比分析的前提是实验模型与盐湖原型的沉积机理具有相似性。基于现代盐湖的野外地质调查，对岩盐析出模型与现代盐湖在沉积物的结构、空间分布以及沉积机理的相似性等方面进行了对比分析。研究表明，深度较小的水槽，以空气-卤水界面析盐和蒸发泵成盐为主；而对于水深和规模较大的现代盐湖来说，上述两种成盐方式主要分布于湖盆边缘的浅水区，水深较大的斜坡带和洼陷带以卤水-湖底沉积物界面析盐为主，反映了水深较浅的水槽无法再现古代盐湖的湖盆底形和沉积物分布特征。现代沉积调查显示，在封闭的内陆盐湖盆地中，岩盐通常形成于湖退期-低位期，其沉积厚度从湖盆边缘向洼陷中心有逐渐增大的趋势，即岩盐的沉积中心和洼陷中心保持一致。岩盐的结构跟沉积环境密切相关，盆缘滨岸带的岩盐多为薄层状与砂岩共存，晶体粒度小；而洼陷带以粗粒结晶的盐岩为主，单层厚度大，常与暗色泥岩互层。岩盐沉积中心和洼陷中心关系的厘定，对于湖盆的古地貌恢复和沉积体的预测，具有重要的理论和现实意义。

The Similarity of Salt-Forming between Flume Experiment and Modern Salt Lake

Salt precipitation simulation experiments help enhance our understanding of salt-forming models; however, the premise of using forward modeling is that the experimental model is similar to the sedimentary mechanism of the salt lake prototype. Based on the field geological survey of modern salt lakes, this paper makes an analogy analysis of salt precipitation models and modern salt lakes, in terms of sediment texture, spatial distribution characteristics, and similarity of sedimentation mechanism. The results show that it is mainly the air-brine interface salt and salt formation through evaporation in the smaller depth of the flume; and for the deeper water and large-scale modern salt lake, the two kinds of salt-forming methods are mainly distributed in the shallow waters of the lake basin. The slopes and depressions with larger water depth are mainly brine-lake sediments interfaced with salt precipitation, which reflect the shallow water of the flume cannot reproduce lake basin bottom and sediment distribution characteristics of the ancient salt lake. Modern sediments show that in the closed inland salt lake basin, the rock salt is mainly formed in the lake retreat period-low period, and its depositional thickness gradually increases from the edge of the lake basin to the depression center, i.e. the deposition center of the rock salt and the depression center are consistent. The texture of rock salt is closely related to the sedimentary environment. The rock salt in the edge of the basin mostly coexists with the sandstone, and the grain size is small, while the depression is mainly composed of coarse-grained salt rock, single-layer thickness and is large, often with dark mudstone interbeds. The relationship between the center of the rock salt deposition and the center of the depression is of great theoretical and practical significance for the restoration of paleogeomorphology and sedimentary body of the lake basin.