Monitoring and Early Warning Technology of Hydrate-induced Submarine Disasters

Abstract

With the depletion of fossil energy sources, such as coal and petroleum, natural gas hydrate has been proposed as an alternative energy source. However, the synthesis of natural gas hydrate may cause marine engineering disasters, such as submarine cable breaks and the collapse of sub-sea oil rigs, and even submarine earthquakes, triggering tsunamis and seriously endangering human safety. Hydrate test production monitoring in various countries focuses on the temperature, pressure, and methane concentration near test production wells. Effective observation equipment and methods for the monitoring and early warning of submarine geological hazards are lacking. This paper reviewed the possible geological hazards caused by deep seawater hydrate mining and the monitoring and early warning technologies for deep seawater hydrate mining in various countries and introduced the in-situ Surveying Equipment of Engineering Geology in Complex Deep Sea (SEEGeo). The equipment uses 3D resistivity measurement and data inversion technology, seabed sediment acoustic measurement and data inversion technology, seabed sediment pore water pressure measurement and data inversion technology, and renewable energy seawater-dissolved oxygen battery power supply technology. SEEGeo can realize the in situ, real-Time, long-Term, effective monitoring and early warning of geological disasters induced by hydrate development. At present, the equipment has conducted two sea trial experiments on the continental slope of the South China Sea, equipped with the "Marine Geology No. 6"scientific research vessel of the Guangzhou Marine Geological Survey and the "Dongfanghong No.3"scientific research vessel of the Ocean University of China, and obtained in situ engineering geological data of the South China Sea.