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Numerical Heat-conduction Modeling to Understand the Genesis of the Observed Geothermal Gradient in Ulleung Island using Experimentally Determined Thermal Properties of the Rocks

울릉도 산출 암석의 열물성 자료를 이용한 울릉도 지열 성인에 대한 열전도 수치모델링 연구

  • Received : 2016.07.04
  • Accepted : 2016.07.20
  • Published : 2016.08.31

Abstract

We have numerically modeled thermal evolution of Ulleung Island after an emplacement of magma chamber. The disk-shape magma chamber is assumed to locate at 2.9 km beneath the island and has a diameter and a thickness of 10 km and 300 (or 600) m, respectively. The geothermal gradients evaluated from the numerical modeling coincide well with the range of the geotherms (${\sim}95^{\circ}C/km$) observed from the well logging. Although there are limitations in the application of the numerical results directly to the interpretation of the observed geotherms, we believe that an existence of a hot magma chamber in molten or in solidified state is the most plausible explanation for the observed geotherms.

Keywords

Ulleung Island;Geotherm;Thermal properties;Magma chamber;Numerical modeling

Acknowledgement

Supported by : 한국에너지기술평가원

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