Elastic properties of granulite facies rocks of Mahabalipuram, Tamil Nadu, India

Journal of Earth system science

K B Chary1¹  K J Prasanna Lakshmi1¹  L P Sarma1¹  M V M S Rao1¹ 

[1] National Geophysical Research Institute, Hyderabad 500 007, India.$$

关键词: Velocities;    Poisson’s ratio;    attenuation;    granulite facies rocks.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

Compressional and shear wave velocities and attenuation measurements have been carried out in some of the borehole samples of acidic, basic and intermediate granulites of Mahabalipuram, Tamil Nadu, India. The results have been obtained at ambient conditions using ‘time-of-flight’ pulse transmission technique at 1.0MHz frequency. The results show linear relationships between velocity and density, and velocity and attenuation properties of the rocks. The acidic granulites show lower velocities and higher attenuation than the intermediate and basic granulites. The average values of the Poisson’s ratio of acidic, intermediate and basic granulites have been found to be 0.210, 0.241 and 0.279 respectively. The variations in velocities and attenuation in these low porosity crystalline rocks are found to be strongly influenced by their mineral composition. The laboratory velocity data (extrapolated to high pressure) of the present study and the published field velocity data from deep seismic sounding studies indicate that these granulite facies rocks may belong to mid-crustal depths only.

【 授权许可】

Unknown