3D Hydraulic Conductivity Modeling of Fractured Granitic Body Using Geostatistical Techniques and Its Application to Regional Groundwater Flow Analysis

DOI Web Site 3 Citations 12 References
  • KUBO Taiki
    Graduate School of Engineering, Kyoto University
  • KOIKE Katsuaki
    Graduate School of Engineering, Kyoto University
  • LIU Chunxue
    School of Urban Management, Resources and Environment, Yunnan University of Finance and Economics
  • KURIHARA Arata
    Dia Consultants Co. Ltd.
  • MATSUOKA Toshiyuki
    Japan Atomic Energy Agency, Geological Isolation Research and Development Directorate, Tono Geoscientific Research Unit

Bibliographic Information

Other Title
  • 地球統計学的手法による亀裂性花崗岩体の3次元透水係数モデリングと広域地下水流動解析への応用
  • チキュウ トウケイガクテキ シュホウ ニ ヨル キレツセイ ハナオカガンタイ ノ 3ジゲン トウスイ ケイスウ モデリング ト コウイキ チカ ミズリュウドウ カイセキ エ ノ オウヨウ

Search this article

Abstract

 Numerical simulations have been the most effective method for estimating flow pattern, flux, and flow velocity of the groundwater to precisely characterize large-scale groundwater systems. Spatial modeling of the 3D distribution of hydraulic conductivity over a study area is indispensable to obtain accurate simulation results. However, such spatial modeling is difficult in most cases due to the limitations of hydraulic conductivity data in terms of their volume and location. To overcome these problems and establish an advanced technique, we adopt geostatistics and combine a fracture distribution model with measured conductivity data, selecting the Tono area situated in Gifu Prefecture, central Japan for the field study. The size of the main target area covers 12 km (E-W) by 8 km (N-S), with a depth range of 1.5 km, and it is chiefly underlain by Cretaceous granite. Because the distribution of 395 hydraulic test data acquired along the 25 deep boreholes was biased, the data values were compared to the dimensions of simulated fractures using GEOFRAC. As a result, a positive correlation was identified. Using a regression equation for the correlation, hydraulic conductivity values were assigned to every simulated fracture. Then, a sequential Gaussian simulation (SGS) was applied to construct a 3D spatial model of hydraulic conductivity using those assumed values and actual test data. The plausibility of the resulting model was confirmed through the continuity of high and low permeable zones. The next step is a groundwater flow simulation using MODFLOW and the model. The simulation results were regarded to be appropriate because distribution of hydraulic head, locations of major discharge points, and anisotropy of hydraulic behavior of the Tsukiyoshi fault correspond to the results of observations. The most noteworthy feature detected in the groundwater flow model from the simulation results is that descending flow, horizontal southward flow at depth, and ascending flow are formed from recharge to discharge areas passing through the Tsukiyoshi fault, which agree with the configuration of the continuous simulated fractures.

Journal

Citations (3)*help

See more

References(12)*help

See more

Related Projects

See more

Keywords

Details 詳細情報について

Report a problem

Back to top