CAJ | 학술논문

西沙群岛中新世以来广泛发育生物礁，记录了大量的构造活动信息。利用在西沙群岛海域取得的单道地震剖面结合前人研究成果，对该区构造运动和活动性进行了研究。研究结果表明：西沙群岛周缘发育多NE-NEE、NW向深大断裂，地块上发育NE、EW向断裂；这些断裂与先存断裂位置基本相同，受多期构造运动的影响多次活动，常伴有火山活动，一些火山出露海底数百米；西南次海盆扩张对中—西沙地块NW向挤压，使西沙群岛处于挤压环境；沿EW向断裂南北两侧地层变形表现出鲜明差异，两侧地层向相反方向逆冲，北侧地层变形较大，说明两侧地层处于不同的构造环境；西沙群岛更新世火山活动停止后，构造趋于稳定，仅部分断裂现今仍活动。
서사군도중신세이래엄범발육생물초，기록료대량적구조활동신식。이용재서사군도해역취득적단도지진부면결합전인연구성과，대해구구조운동화활동성진행료연구。연구결과표명：서사군도주연발육다NE-NEE、NW향심대단렬，지괴상발육NE、EW향단렬；저사단렬여선존단렬위치기본상동，수다기구조운동적영향다차활동，상반유화산활동，일사화산출로해저수백미；서남차해분확장대중—서사지괴NW향제압，사서사군도처우제압배경；연EW향단렬남북량측지층변형표현출선명차이，량측지층향상반방향역충，북측지층변형교대，설명량측지층처우불동적구조배경；서사군도경신세화산활동정지후，구조추우은정，부부분단렬현금잉활동。
Organic reef, widely developed since the Miocene around the Xisha Islands, provides rich information of tectonic movement and activity. Using single-channel seismic profiles acquired and combining with other research in this area, this paper discusses the tectonic movement and activity around the Xisha Islands. The results show that there are NE-NEE and NW trending faults along the Xisha block boundary and NE and EW trending faults in the Xisha block. These faults are inherited from old ones, and the reactivation of the faults accompanied by volcanicity is affected by multiphase tectonic movements. Result from the NW direction stress caused by the opening of the Southwest Sub-basin, the Zhong-Xisha block is in a compression environment. The seismic profile shows that there is a distinct difference between the two sides of the EW fault in terms of formation, which indicates that the two sides of the formation are in different tectonic environments. After the Pleistocene, volcanic and most of faulting activity stopped, and the Xisha Islands behave as a stable tectonic entity.