DEEP BASEMENT RESERVOIR IN TIANJIN GEOTHERMAL FIELD

Abstract

The Tianjin geothermal field is a typical low-temperature system, which is located in the middle-lower reaches of the Haihe River System on the North China plain. The reservoir in bed rock is the main developing aquifer.The mainly feeding chan-nels are the karst conduits in weathering carbonate rock of Proterozoic and Lower Paleozoic. It is an extensive zone with the temperature of 76-100?.The production rate of the whole field reached nearly 13Mm3 in 1999. A numerical model for this geothermal field is set up, using the Aqua3D program. The characteristics of the reservoir are calibrated and matching the measured and calculated water level from 48 production wells over the past 20 years. Based on this, predictions of the reservoir response to the planned production and reinjection rates were made up to the year 2009. The flow model indicates that the draw-down water level can be reduced to 150m in prediction period.