Evaluation of effectiveness of 3-D resistivity surveys

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10650916
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 資源開発工学
• Research Institution: KYUSHU UNIVERSITY
• Principal Investigator: SASAKI Yutaka KYUSHU UNIVERSITY, GRADUATE SCHOOL OF ENGINEERING, RESEARCH ASSOCIATE, 大学院・工学研究科, 助手 (10128027)
• Project Period (FY): 1998 – 1999
• Keywords: 3-D resistivity survey / Inversion

Research Abstract

Numerical simulations of resistivity method show that 3-D survey gives far more better resolution and accuracy than conventional 2-D surveys. With 2-D surveys, it is possible to locate near-surface anomalies, but they are likely to generate artifacts at depth due to the breakedown of 2-D assumption. With respect to the survey geometry, this study mainly focus on 'multiple, parallel profile survey', which is an extended version of 2-D survey geometry. A summary of important points derived from simulations are :
1. For the near-surface inhomogeneites, the 3-D survey gives almost perfect reconstruction regardless of the electrode arrays unless data is undersampled. On the other hand, the resolution for the target at depth depends on the electrode array used.
2. If the data has the same quality, the dipole-dipole array gives better performance than the pole-pole array.
3. When the pole-pole array is used, the cross-line data should be added to the in-line data to enhance the resolution.