Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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A Study on Hydraulic Characteristics of Permeable Rock Fractures in Deep Rock Aquifer Using Geothermal Gradient and Pumping Test Data

지온경사와 양수시험 자료를 활용한 심부 암반대수층 투수성 암반균열의 수리특성 연구

  • Hangbok Lee (Deep Subsurface Storage and Disposal Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Cholwoo Lee (Deep Subsurface Storage and Disposal Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Eui-Seob Park (Deep Subsurface Storage and Disposal Research Center, Korea Institute of Geoscience and Mineral Resources)
  • 이항복 (한국지질자원연구원 심층처분환경연구센터) ;
  • 이철우 (한국지질자원연구원 심층처분환경연구센터) ;
  • 박의섭 (한국지질자원연구원 심층처분환경연구센터)
  • Received : 2024.07.22
  • Accepted : 2024.08.16
  • Published : 2024.08.31
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Abstract

In various underground research projects such as energy storage and development and radioactive waste disposal targeting deep underground, the characteristics of permeable rock fractures that serve as major pathway of groundwater flow in deep rock aquifer are considered as an important evaluation factor in the design, construction, and operation of research facilities. In Korea, there is little research and database on the location and hydraulic characteristics of permeable rock fractures and the pattern of groundwater flow patterns that may occur between fractures in deep rock boreholes. In this paper, the hydraulic characteristics of permeable rock fractures in deep rock aquifer were evaluated through the analysis of geothermal gradient and pumping test data. First, the deep geothermal distribution was identified through temperature logging, and the geothermal gradient was obtained through linear regression analysis using temperature data by depth. In addition, the hydraulic characteristics of the fractured rock were analyzed using outflow temperature obtained from pumping tests. Ultimately, the potential location and hydraulic characteristics of permeable rock fractures, as well as groundwater flow within the boreholes, were evaluated by integrating and analyzing the geophysical logging and hydraulic testing data. The process and results of the evaluation of deep permeable rock fractures proposed in this study are expected to serve as foundational data for the successful implementation of underground research projects targeting deep rock aquifers.

지하 심부를 대상으로 하는 에너지 저장 및 개발, 방사성폐기물 처분 등 여러 지하연구사업들에서 심부 암반대수층 내 지하수 흐름의 주요 통로가 되는 투수성 암반균열의 특성 정보들은 연구시설의 설계와 건설 그리고 운영에 있어 중요한 평가 요소로 고려된다. 국내에는 심도가 매우 깊은 암반시추공에서 투수성 암반균열의 위치와 수리특성, 균열 사이에 발생할 수 있는 지하수 유동 양상에 관한 연구와 데이터베이스가 매우 부족한 실정이다. 본 논문에서는 지온경사와 양수시험 자료분석을 통해 심부 암반대수층 내 투수성 암반균열의 수리특성을 평가하였다. 먼저 온도검층을 통해 심부 지온 분포를 확인하고, 심도별 온도자료를 이용하여 선형회귀분석을 통해 지온경사를 도출하였다. 또한 양수시험을 통한 용출온도를 이용해, 균열암반에 대한 수리특성을 분석하였다. 최종적으로 이러한 물리검층과 수리시험 자료를 통합 분석함으로써 투수성 암반균열의 잠재적 위치와 수리특성, 그리고 시추공 내 지하수 흐름을 평가하였다. 본 연구에서 제안된 심부 투수성 암반균열의 특성평가 과정과 결과들은 심부 암반대수층을 대상으로 하는 지하연구사업들의 성공적인 수행을 위한 기초 자료로 활용될 것으로 기대된다.

Keywords

Acknowledgement

본 연구는 한국지질자원연구원 기본사업인 '심지층 개발과 활용을 위한 지하심부 특성평가 기술개발(과제코드 : GP2020-010, 과제 번호: 24-3414)' 지원을 받아 수행되었습니다.

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