XUE Yuze, ZHANG Yugui, MA Yinjuan, et al. Reinjection tracer test of karst geothermal reservoir in the southeastern margin of Ordos Basin[J]. Petroleum Reservoir Evaluation and Development, 2023, 13(6): 757-764. DOI: 10.13809/j.cnki.cn32-1825/te.2023.06.006.
Reinjection plays a crucial role in maintaining the pressure of geothermal reservoirs
extending the lifespan of geothermal fields and preserving the environment. In the Hancheng area
located at the southeastern margin of the Ordos Basin in Shaanxi province
there is an abundance of karst geothermal resources. Despite this
the level of development and utilization of these resources in the region remains relatively limited. To further evaluate the development potential of Karst geothermal resources in the region
we implemented a karst geothermal heating project and conducting a tracer test
employing NH
4
SCN as the tracer. The goal was to establish an hydraulic connection between the production well and the reinjection well. Utilizing the thermal breakthrough model
predictions were made regarding the cha
nges in the temperature of the production well as a consequence of long-term reinjection. The findings suggest that there is a primary direct pathway for the flow of water
and possibly a secondary path that may contribute to groundwater storage. The temperature of production well's water is projected to decline by 8.31 ℃ over 100 years due to the reinjection process. However
this decline is not expected to cause a severe temperature drop in the geothermal reservoir within this dual-well system.