Previous work has largely discussed the relations between sediment structures and accumulation of gas hydrates in the Shenhu area of South China Sea, but has not documented why the gas hydrates occurred at the seafloor topographic highs. Many gas hydrate exploration examples abroad also indicate that the saturation of gas hydrates was higher at seafloor topographic highs. This work aims to understand why gas hydrates accumulated at topographic highs and why their saturation is higher.
The amalgamation and breakup mechanisms of the Rodinia supercontinent during the Meso- and Neoproterozoic have been the focus of much research. However, few studies have examined the response of Neoproterozoic tectonics and magmatism along the northeastern margin of the Yangtze Plate to synchronous global events. The Qianliyan Uplift is located on the eastern margin of the Sulu orogenic belt in the ocean, but the tectonic affinity of the uplift and its relationship to the Sulu orogenic belt remains unclear. In this study, we investigated the formation age, geochemical characteristics, genesis type, and affinity of the granitic gneiss on Chaolian Island of the Qianliyan uplift and its tectonic significance.