Details

Autor(en) / Beteiligte

• Bai, Guogang
• Sun, Qiang
• Geng, Jishi
• Wang, Shaofei
• Jing, Xudong

Titel

Resistivity of granite and sandstone varies with frequency and water saturation

Ist Teil von

• Geomechanics and geophysics for geo-energy and geo-resources., 2022-12, Vol.8 (6), Article 198

Ort / Verlag

Cham: Springer International Publishing

Erscheinungsjahr

2022

Quelle

SpringerLink

Beschreibungen/Notizen

• Exploring the effects of excitation polarization and moisture saturation on rock resistivity is crucial for evaluating resistivity-related technologies and engineering, such as electrical exploration. This study selected granite and sandstone from Shandong and Wanzhou to evaluate the rock resistivity at various frequencies (0.1 ~ 200 kHz) and saturations (0 ~ 100%). Under conditions of low saturation of granite and sandstone, the results indicate that the resistivity of the rock sample will rise with increasing saturation due to the excitation polarization effect. As the saturation corresponding to the peak resistivity is approached, the influence of pore water on resistivity replaces the primary role of the excitation polarization effect, resulting in a fall in the resistivity of the rock sample with the increase in saturation. Furthermore, the exponential function relationship between peak saturation and frequency is positively correlated, and peak saturation increases rapidly with increasing frequency due to the disappearance of interface polarization at 10 4  ~ 10 5  Hz, with an increase of about 60%. Article highlights With the increase of saturation, pore water content is the main factor affecting the resistivity of granite and sandstone. The peak resistivity of granites and sandstones has an exponential positive correlation with the increase in frequency. The effects of different frequencies (0.1~200kHz) and saturation (0~100%) on the resistivity of granite and sandstone were studied.