三山岛金矿新立矿区是我国唯一一座海底金属矿山，其对开采技术要求较高，大规模海底开采过程中潜存的安全问题是矿山需解决的首要问题。其中，海底第四系底部黏土隔水层和F1断层泥是阻水的关键部位，这2处隔水层破坏后有可能会造成海水溃入，因此需要探明矿区上覆岩层的地质结构，尤其是黏土隔水层分布情况。经过探索形成了高精度三维地震勘探技术，包括灵活的采集几何，低噪声接收器条件和定量控制等，并在开展新立矿区海底地震勘探中取得了很好的效果。研究表明：在矿区地质勘查中，三维地震勘探方法可在较大深度范围内精细探测浅层与深部的地质结构形态，是一种有效且实用的技术方法；第四系在探测区稳定分布，埋深在8～39 m之间，主要表现为西部和北部偏薄，南东方向地层逐渐变深，其中第四系底部的黏土隔水层厚度变化范围为1～11 m，分布趋势与第四系基本一致，但在F1断裂附近明显变薄，厚度为2.5～5.0 m，并向北西方向逐渐变薄，隔水稳定性变差，对矿床开采具有一定的风险；下覆基岩强、中、弱3层风化带总的厚度变化范围为3～35 m，在F1断裂附近风化带明显变厚，厚度为20～35 m，是矿区主要的透水结构。高精度三维地震技术首次应用于新立矿区的地质结构探测中，为三山岛金矿海底矿区的安全开采设计提供了数据支持。

Sanshandao gold mine is divided into two mining areas.One is the Xishan mining area，whose orebody is buried on land,the other is the Xinli mine area.It is the only undersea metal mines in China，its mining technology demand is higher，and also have serious security problems.Among them，the clay aquifer of the Quaternary bottom and F1 fault mud are the key parts of water blocking，and the two aquifers will cause seawater to break into.Therefore，it is necessary to ascertain the geological conditions of the overlying strata in the mining area，especially the distribution of the clay aquifer.After exploration，high precision three-dimensional seismic exploration technology including flexible acquisition geometry，low noise receiver conditions and quantitative control has been formed.The foundation of 3D seismic exploration technology is 2D seismic exploration technology.3D seismic exploration is more accurate and spatially stereoscopic than the data obtained by 2D seismic exploration，but it also has higher requirements for the exploration environment.This paper briefly discusses the difficulties and countermeasures of exploration，the layout and data collection of exploration lines，the fine interpretation of the overlying layer and the hydraulic connection between the overlying strata and seawater.In the submarine seismic exploration in the Xinli mining area，good results have been achieved，as follows：In the geological exploration of mining areas，the 3D seismic exploration method can accurately detect the geological structure of shallow and deep in a large depth range，which is an effective and practical technical method.In this submarine seismic exploration in the Xinli mining area，good results have been achieved.The specific understanding is as follows：The Quaternary is stably distributed in the detection area，buried in depth of 8～39 m，which is mainly characterized by the thinness of the stratum in the west and the north and the deepening of the stratum in the southeast.Among them，the thickness of clay aquifer at the bottom of Quaternary varies in the range of 1～11 m，and the distribution trend is basically the same as Quaternary.But it thins obviously near the F1 fault，the thickness is 2.5～5.0 m，and thins gradually to the north-west direction，and the stability of aquifer becomes worse，which has a certain risk to the mining of the deposit.The total thickness of the weathering zone of the underlying bedrock in strong，medium and weak layers varies in the range of 3～35 m.The weathering zone near the F1 fault is obviously thicker，with a thickness of 20～35 m，which is the main permeable structure in the mining area.High-precision three-dimensional seismic technology was first applied in the geological structure exploration of the Xinli mining area，which provided data support for the safe mining design of the submarine mining area of the Sanshandao gold mine.