Introduction
Most geothermal reservoirs consist of fracture system containing steam and very hot water. In order to exploit such energy resources,it is first necessary to locate the reservoirs. However, doing this is both difficult and costly and it forms a major obstacle to geothermal development. It is essential, therefore, to explore geothermal reservoirs efficiently. In conducting geothermal development, experts have recognized recently that it is necessary to identify not only fractures, but also the behavior of the fluid within those factures.This is because isolated and sealed fractures do not contribute to geothermal energy flow.
The geothermal laboratory of New Energy and Industrial Technology Development Organization (NEDO) research on the following three techniques, as part of the Research and Development projects of its Geothermal Energy Center that launched 'the core analysis system project' during the Fiscal Years 1993 to 1996 and 'the model support technique project' since Fiscal Year 1997.