Gravity Anomalies EOLSS（重力异常EOLSS）.pdfVIP

GEOPHYSICS AND GEOCHEMISTRY – Vol.III - Gravity Anomalies - D. C. Mishra GRAVITY ANOMALIES D. C. Mishra National Geophysical Research Institute, Hyderabad, India Keywords: gravity anomalies, isostasy, Free Air and Bouguer gravity anomalies Contents 1. Introduction 2. Free Air and Bouguer Gravity Anomalies 3. Separation of Gravity Anomalies 3.1 Regional and Residual Gravity Fields 3.2 Separation Based on Surrounding Values 3.3 Polynomial Approximation 3.4 Digital Filtering S S 4. Analytical Operations S R 4.1 Continuation of the Gravity Field 4.2 Derivatives of the Gravity Field L E 5. Isostasy 5.1 Isostatic Regional and Residual Fields O T 5.2 Admittance Analysis and Effective Elastic Thickness E P 6. Interpretation and Modeling 6.1 Qualitative Interpretation and Some Approximate Estimates – A 6.2 Quantitative Modeling Due to Some Simple shapes 6.2.1 Sphere H 6.2.2 Horizontal Cylinder O C 6.2.3 Vertical Cylinder 6.2.4 Prism C 6.2.5 Contact S E 6.3 Gravity Anomaly Due to an Arbitrary Shaped Two-dimensional Body L 6.4 Basement Relief Model E 7. Applications P 7.1 Bouguer Anomaly of Godavari Basin, India N 7.2 Spectrum and Basement Relief U M 7.3 Modeling of Bouguer Anomaly of Godavari Basin Along a Profile A 7.4 Some Special Applications Glossary S Bibliography Biographical Sketch Summary Gravity anomalies are defined in the form of free air and Bouguer anomalies. Various methods to separate them in the regional and the residual fields are described, and their limitations are discussed. Polynomial approximation and digital filtering for