2010 Fiscal Year Final Research Report

Estimation of permeability distribution for cracked medium by wave velocity and permeability tensor

Research Project

Project/Area Number	21760681
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Earth system and resources enginnering
Research Institution	Nihon University
Principal Investigator	TAKEMURA Takato Nihon University, 文理学部, 講師 (30359591)
Project Period (FY)	2009 – 2010
Keywords	透水テンソル / クラックテンソル / 亀裂密度 / 弾性波速度
Research Abstract	In order to propose the hydrogeological model, we try to estimate permeability tensor defined by crack geometry and wave velocity. The permeability testing method was developed by using newly introduced vessel for permeability measurement and high-accuracy pump, and the permeability dependence with coffining pressure was measured. Here, the confining pressure is changing 0 to 10MPa. Additionally, the crack geometry was estimated by the multi directional wave velocity using the developed crack geometry - wave velocity relation. In this study, crack density per unit volume and crack anisotropy could be estimate by the distribution of wave velocities. The estimated permeability is almost correspond with the measured permeability.