New Data on the Deep Structure of the Northern Part of the Gulf of Tonkin in the South China Sea Based on the Results of Magnetotelluric Soundings

摘要

We present a geoelectric model for the northern part of the Gulf of Tonkin in the South China Sea, which was developed for the first time based on the data of magnetotelluric studies carried out in 2012-2013. The existence of a regionally developed aniso-tropic conducting fractured horizon and a steeply dipping electrically conductive fault zones is a distinguishing property of this model, which has a layer-block structure. The nature of the zones of electric conductivity is related to the accumulation of a water-graphite mixture during long-term propagation of the flow of deep gases, which include H_2 and CH_4. This allows us to consider the outcrops of the deep fluid saturated fractures as potential oil bearing regions.