Full gravity gradient tensors from vertical gravity by cosine transform
Jiang Fu-Yu1, Huang Yan2, and Yan Ke2
1. Hohai University, School of Earth Sciences and Engineering, Nanjing 210098, China.
2. Geology Exploration Technology Institute of Jiangsu Province, Nanjing 210048, China.
Abstract：
We present a method to calculate the full gravity gradient tensors from pre-existing vertical gravity data using the cosine transform technique and discuss the calculated tensor accuracy when the gravity anomalies are contaminated by noise. Gravity gradient tensors computation on 2D infi nite horizontal cylinder and 3D “Y” type dyke models show that the results computed with the DCT technique are more accurate than the FFT technique regardless if the gravity anomalies are contaminated by noise or not. The DCT precision has increased 2 to 3 times from the standard deviation. In application, the gravity gradient tensors of the Hulin basin calculated by DCT and FFT show that the two results are consistent with each other. However, the DCT results are smoother than results computed with FFT. This shows that the proposed method is less affected by noise and can better refl ect the fault distribution.
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2012, Vol. 9 
