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2015 Vol.52, Issue 2 Preview Page

Research Paper

Work Flow for Differential Horizontal Stress Ratio Fromshale Gas Seismic Data

셰일가스 탄성파자료로부터 수평응력 차 비 구하는 공정도 연구

장성형

Seonghyung Jang

30 April 2015. pp. 158-170
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Abstract
Horizontal drilling and hydraulic fracturing which are the key technology in unconventional shale gasdevelopment are applied to the sweet spot where Young\'s modulus is high, Poisson\'s ratio is low, and differentialhorizontal stress ratio(DHSR) is low. Petrophysical parameters such as velocities, Young\'s modulus, Poisson\'s ratio,and anisotropic coefficients from seismic data are important for developing shale gas. It is also necessary forcalculating DHSR which is a function of maximum horizontal stress and minimum horizontal stress. DHSR consistsof normal compliance matrix which are function of weakness and Thomsen\'s anisotropic parameters. In this study,I suggest a flow for calculating DHSR from seismic data and verify it through synthetic data. Thomsen\'s parameter was decided by nonhyperbolic semblance analysis and it showed that  is getting more sensitivity to NMOvelocity according to the higher anisotropic characteristics. When we apply the nonhyperbolic semblance analysisto field data set, we need to analyze it carefully.
Keywords
Unconventional
Shale gas
Anisotropy
Nonhyperbolic semblance
Differential horizontal stress ratio(DHSR)
비전통 에너지자원인 셰일가스 개발에서 필수기술에 해당하는 수평시추와 수압파쇄는 셰일가스 집중구간에서 포아송비가 낮고 영률이 높은 지역, 수평응력차비(DHSR)가 낮은 구간에서 적용된다. 탄성파자료로부터 구할 수 있는 속도, 영률, 포아송비, 이방성계수 등 암석역학적 매개변수는 셰일가스 개발에 중요한 역할을하며 수평방향 최대 및 최소 압력 함수로 표현되는 DHSR 계산에 필수적인 변수이다. DHSR은 균열매개변수함수로 이루어진 수직방향 컴플라이언스 계수가 필요하며 균열매개변수는 톰슨 이방성변수로 표현할 수 있다.본 연구에서는 탄성파자료로부터 DHSR을 구하는 공정도를 제시하고 수치모형실험을 통해 검증하였다. 톰슨이방성변수 는 비쌍곡선 유사도 등고선을 이용하여 구하였으며 이방성 매질 특성이 커질수록 는 NMO속도에대한 민감도가 커져 현장자료에 적용하기 위해서는 철저한 분석이 필요하다.
키워드
비전통
셰일가스
이방성변수
비쌍곡선 유사도 등고선(nonhyperbolic semblance)
수평응력차비(Differential Horizontal Stress Ratio: DHSR)
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Information
  • Publisher :The Korean Society of Mineral and Energy Resources Engineers
  • Publisher(Ko) :한국자원공학회
  • Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
  • Journal Title(Ko) :한국자원공학회지
  • Volume : 52
  • No :2
  • Pages :158-170
  • DOI :https://doi.org/10.12972/ksmer.2015.52.2.158
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