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礼乐地块位于南沙海域东北部,主要由2部分组成:礼乐滩和礼乐盆地.根据重力和地震数据研究礼乐地块的主要构造特征和地壳结构.基于多道地震数据,主要研究了基底之上的地层和断裂构造,并通过重力数据反演分析了地块深部地壳结构.礼乐滩区域主要为碳酸盐岩地层,此区域地层较平,断裂不发育.而礼乐盆地区域早期断裂较为发育,并且主要发育2种构造:翘倾断块和宽缓背斜;中生代地层厚度自SW向NE减薄,但张裂期地层自SW向NE增厚,这表明在张裂阶段断层活动强度自SW向NE增强,离张裂中心越近,断裂活动强度越大.礼乐地块以正布格重力异常为主(60～140mGal),莫霍面深度约16～27km,拉张因子为1.3～2.0,属于减薄型大陆地壳.
The ritual plots are located in the northeastern part of the Nansha Sea and are mainly composed of two parts: Li Yue Tan and the Li Le Basin. The main tectonic features and crustal structure of the Rieu block are studied based on gravity and seismic data. Based on multi-channel seismic data, The stratigraphy and fault structure above the basement are analyzed, and the deep crustal structure of the block is inversed and analyzed by gravity data.The areas of Li-Yue-Tan are mainly carbonate strata, and the strata in this area are relatively flat and the faults are not developed. There are two kinds of tectonic faults in the area: the upwelling fault and the broad and gentle anticline; the thickness of the Mesozoic strata decreases from SW to NE, but the thickness of the stratum in the period from SW to NE is thicker, The intensity of fault activity increases from SW to NE, and the closer to the center of the fracture, the greater the activity intensity of the fault.The Rieu Block is dominated by Zhengbuge gravity anomaly (60-140mGal) and Moho depth is about 16-27km, Tension factor of 1.3 to 2.0, belonging to the thinned continental crust.