The brine-seawater interface (BSI) is a unique type of groundwater-seawater interface (GSI) characterized by the higher density of underground brine compared to seawater. This study focuses on characterizing the bay-scale BSI morphology and identifying submarine-groundwater discharge windows using a comprehensive in-situ geophysical detection on the south bank of Laizhou Bay. Our findings reveal that the BSI forms an extensive mixing zone (15–20 km) without distinct contours between waters of varying salinities. The discharge windows for underground brine are located in nearshore areas with fine sand distribution and offshore pockmark areas. Hydraulic and salinity gradients drive the underground brine discharge through these windows. The aquitard window is the primary area for shallow and deep brine exchange, likely evolved from paleochannels, ancient tidal creeks, or ancient underwater barriers. These findings provide crucial modeling support for analyzing environmental evolution mechanisms and theoretical basis for planning the underground brine mining in similar coastal regions.

中文翻译：

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泥滩滩盐海水界面形态及海底地下水排放窗空间分布


盐水-海水界面 （BSI） 是一种独特的地下水-海水界面 （GSI），其特点是与海水相比，地下盐水的密度更高。本研究的重点是在莱州湾南岸使用全面的原位地球物理探测来表征海湾尺度的 BSI 形态并确定海底-地下水排放窗口。我们的研究结果表明，BSI 形成了一个广泛的混合区（15-20 公里），在不同盐度的水域之间没有明显的轮廓。地下卤水的排放窗口位于细沙分布的近岸地区和海上麻点区域。水力和盐度梯度驱动地下盐水排放通过这些窗口。滞水层窗口是浅层和深层盐水交换的主要区域，可能是从古河道、古老的潮汐小溪或古老的水下屏障演变而来的。研究结果为分析环境演化机制提供了重要的建模支持，为类似沿海地区地下卤水开采规划提供了理论依据。