Analysis of Tracer Test Data in the Laugaland Geothermal Field, S-Iceland
冰岛LAUGALAND地热田示踪试验与回灌温度模拟

The temperature decline of production wells is a potential problem induced by reinjection.At Laugaland,in order to assess and predict the temperature changes resulting from reinjection,a tracer test was carried out as an effective tool for quantitatively studying the hydraulic connection between production and injection wells.The analysis of the tracer test data indicates that the connection between the injection well GN-1 and production well LWN-4 is fairly direct.Based on the tracer test,the reinjection-induced temperature decline of the production well LWN-4 was predicted under different hypotheses and production-reinjection scenarios.The calculated temperature decline is,however,a few degrees greater than the actual cooling observed.The discrepancy is mainly attributed to a drastic change in flow conditions because of reduced production since reinjection started.In addition,the major earthquakes in 2000 may also have influenced the flow-pattern in the reservoir at Laugaland.