南海北部地球物理科学考察实验研究

The Northern South China Sea (SCS) sharing geophysical survey cruise plans to conduct 9 profiles in the Dongsha sea area, northeastern SCS. These profiles include: 2 for deep seismic survey, 5 for multi-channel seismic (MCS) and shallow seismic profile survey, and another 2 for seismic oceanography survey. 32 Ocean Bottom Seismometer (OBS) was set along two deep seismic profiles, and single channel seismic survey will be carried along the same profile. With the deep seismic, MCS and high resolution shallow seismic profile surveys, this project aimed to get the stratigraphy and deep structure of this area, to better understanding the magmatic activity and tectonic evolution, and to reveal the dynamics of from continental extension, rifting, to sea-floor spreading of SCS, and thus provides background knowledge and basic data for the study of thermo-tectonic evolution of oil-gas baring Cenozoic basin in this area. Besides, seismic oceanography survey was planned to be carried out to gain the physical oceanography features of internal solitary wave afferent from Luzon straight.

南海北部地球物理科学考察航次在南海东北部东沙海域布设9条测线，包括深地震调查测线2条，多道地震和浅剖调查测线5条，地震海洋学调查测线2条。其中，深地震测线设海底地震调查站位32个，并且同步开展单道地震调查。通过对该区进行深地震、多道地震和高分辨率浅地层剖面调查，以获取该区由浅至深的地层和深部地壳结构，了解这一区域的岩浆活动与构造演化，揭示其在南海由陆缘伸展张裂至张开过程中的动力学机制，并为该区新生代含油气盆地的热-构造演化提供背景资料和基础数据。通过在该区开展的地震海洋学调查，研究东沙海区由吕宋海峡传入的孤立内波的物理海洋特征。

南海北部地球物理科学考察航次在南海北部东沙-中沙海域布设三维OBS调查网格、一条二维OBS测线、6条多道地震反射测线、10条高分辨率浅层地震剖面、2条地震海洋学水体反射测线，以揭示该区在南海张裂至张开过程中的构造响应，研究洋、陆过渡壳特征，为该区新生代含油气盆地的热-构造演化研究提供背景资料；航次顺利完成了调查任务，获得了高质量的地震数据。航次过程中还进行了海底热流探针、全光纤多道电缆、24道固体电缆、GI枪等仪器设备的海上试验工作，取得了较好的试验效果，为国产新仪器的研发和应用提供了宝贵数据。