Estimate of Enhanced Geothermal System (EGS) Potential in Mainland Red River Basin, Vietnam

Abstract

The Red River basin is said to be the hottest heating regime compared to the other basins of Da Nang, Nam Con Son and Cuu Long in Vietnam territory with thermal conductivity - 3.37W/mK; geothermal gradient - 35.9K/km and heat flow - 118 mW/m2. So far, geological and tectonic studies have shown that most of the surface area of the Red river basin is covered by the Quaternary sediments, the underneath formations are Neogene then Paleogene sediments. The overall thickness of these sediment layers is unstable from zero to thousands of meters. The basement rocks are found at very deep levels and are composed of diverse and inhomogeneous formations. Making use of data from 19 wells to 1,200 m depth of the "Investigating and General Assessing the Coal Resources in Mainland of Red River Basin" project, the initial assessment of Enhanced Geothermal System potential in mainland of Red river basin is conducted following the method which has been recently applied in some countries in the world. The parameters of porosity, heat conductivity, U, Th and K contents of the well cores as well as gamma radiation, thermal gradients in the wells are analyzed and computed, along with the physical figures of the deep sedimentary layers those are referenced from studies in the world, the potential of enhanced geothermal system is calculated for the study area in the depth from 3 to 7 km is 133,600 MWe.