1st Edition
Gravity and Magnetic Methods for Geological Studies Principles, Integrated Exploration and Plate Tectonics
Gravity and magnetic methods can be directly related to physical properties of rocks, i.e. the density and the susceptibility, and are very useful to field geologists and geophysicists in the mapping and identification of various rock types. They are also used for the detection of minerals with large contrast in density and susceptibility compared to country rock.
This reference volume consists of two parts: The first part describes the basic principles and methodology of the gravity and the magnetic methods of geophysical exploration with global examples. It deals with geological studies and gravity & magnetic methods; geodynamic studies (plate tectonics, crustal structures, plume tectonics); resource exploration (geological mapping, hydrocarbon, mineral and groundwater exploration); environmental studies (seismotectonics, engineering sites, climate changes, mining geophysics, volcanoes and volcanic activity, landslides, impact craters) and different modes of surveying. The second part is dedicated to the Indian Continent and deals with the application of geological data, integrated with other geophysical and geological information. It discusses geodynamics and seismotectonics with respect to the Indian Plate zone, including the Indian Ocean, Himalaya, Tibet and Archean- Proterozoic Cratons and Mobile Belts. It also presents ways for integrated exploration for hydrocarbons, minerals, groundwater and a number of environmental issues relevant in engineering and archaeology.
The accessible style of this unique work will benefit researchers, professionals, advanced students and interested readers in Geophysics, Geology, Economic Geology, Geological Engineering, Geography, Mineralogy and related disciplines.
Part I: Methodology with Global Examples (Continental, Marine and Airborne – Satellite Surveys)
Chapter 1 Introduction
- 1.1 Geological Studies and Gravity and Magnetic Methods
Chapter 2 Gravity Method
- 2.1 Introduction
- 2.2 Basic Principles
- 2.3 Instruments and Data Acquisition
- 2.4 Corrections and Reduction of Gravity Data
- 2.5 Post Processing Analysis and Isostasy
- 2.6 Special Gravity Surveys – Marine, Airborne and Satellite Surveys
- 2.7 Interpretation
- 2.8 Applications: Gravity Anomaly and Related Maps of India
- 2.9 Field examples and Gravity Signatures: Extensional Tectonics
- 2.10 Compressional (Convergence) Tectonics: Recent Convergent Margins and Subduction Zones
- 2.11 Ancient Collision Zones: Proterozoic and Paleozoic convergence
- 2.12 Comparitive study of Different Gravity and Magetic Surveys and Expected Anomalies for Different Targets and Temporal variations in Gravity Field
Chapter 3 Magnetic Methods
- 3.1 Introduction and Basic Principles
- 3.2 Rock Magnetism and Paleomagnetism
- 3.3 Instruments and Data Acquisition
- 3.4 Corrections and Presentation of Magnetic Data
- 3.5 Data Processing
- 3.6 Special Magnetic Surveys
- 3.7 Interpretation of Magnetic Anomalies
- 3.8 Field Examples: Geodynamic Studies and Mineral Exploration
Chapter 4 Common Data Processing Methods and Parameter Estimation - Digital Signal Processing
- 4.1 Regional and Residual Separation
- 4.2 Spectral Analysis
- 4.3 Fourier Transform of Gravity and Magnetic Fields: Layered Model and Basement Relief
- 4.4 Admittance Analysis and Coherence
- 4.5 Linear Inversion and Parameter Estimation
- 4.6 Field Examples: Harmonic Inversion and Geodynamic Studies
- 4.7 Field Examples: Basement Model and Geological Mapping
Part II Integrated Exploration of Indian Plate and Resources (Geodynamics, Seismotectonics, Hydrocarbons, Minerals, Groundwater, Environment and Engineering Sites)
Chapter 5 Continental Drift and Plate Tectonics: Reconstructions, Gondwanaland Break-Up, Plumes and Drifting of Indian Plate
- 5.1 Continental Drift
- 5.2 Plate Tectonics
- 5.3 Mantle Plumes and Break up of Gondwanaland
- 5.4 Indian Ocean
- 5.5 Arabian Sea and Bay of Bengal: Satellite Derived Gravity Maps
- 5.6 Conjugate Structures of India and Antarctica: Eastern Margin of India and East Antaretica
Chapter 6 Collision of Indian and Eurasian Plates and Seismotectonics: Himalayan and Tibetan Terrains
- 6.1 Introduction
- 6.2 Central and Eastern Himalaya, Burmes Arc and Tibet – Crustal and Lithospheric Structures
- 6.3 Western Fold Belt (Pakistan) and Syntaxis, and NW Himalaya – Crustal and Lithospheric Structures
- 6.4 Geodetic Measurements and Deformation Models
- 6.5 Summary
Chapter 7 Geodynamics of the Indian Continent and Seismotectonics: Isostasy, Archean – Proterozoic Cratons, Collision Zones, Rift Basins, Plumes and Lithosphere, and it’s Flexure
- 7.1 Archean – Proterozoic Tectonics
- 7.2 Geophysical Signatures
- 7.3 Bouguer Anomaly Map of India vis-à-vis Geology and Tectonics
- 7.4 Broad Tectonic Zones of Indian Shield
- 7.5 Aravalli-Delhi Mobile Belt (ADMB) and Western Rajasthan
- 7.6 Satpura Mobile Belt (SMB)
- 7.7 Godavari Proterozoic Belt (GPB) and Gondwana Basins – Crustal Structures and Proterozoic Triple Junction and Seismicity
- 7.8 Peninsular Shield: Eastern and Western Dharwar Cratons and Deccan Volcanic Province
- 7.9 Southern Granulite Terrain (SGT)
- 7.10 Eastern Ghat Mobile Belt (EGMB) and Adjoining Cuddapah, and Coastal Godavari Basins
- 7.11 Lithosphere and Asthenosphere under the Indian Continent
- 7.12 Conclusions: Archean Proterozoic Convergence Model of Indian Cratons, Rifted Platforms, Plumes, and Basins
Chapter 8 Seismotectonics and Geodynamics: Bhuj, New Madrid and Sumatra Earthquakes and Tsunami with Co-Seismic Changes
- 8.1 Introduction – Grabens and Horsts
- 8.2 Bhuj Earthquake of January 26, 2001
- 8.3 Source Parameters of the Bhuj Earthquake from Post Seismic Elevation and Gravity Changes
- 8.4 Sumatra Earthquake of December 26, 2004 and Related Tectonic Settings
- 8.5 Co-Seismic Changes, Precursors, and Natural Disaster Management
Chapter 9 Resource Exploration and Geodynamics: Hydrocarbons, Groundwater, and Minerals
- 9.1 Introduction
- 9.2 Saurashtra, NW India – Hydrocarbon and Groundwater Exploration and Geodynamics
- 9.3 Kachchh – Mesozoic Sediments and Basement Model
- 9.4 Cambay Basin and its Extension in Western Rajasthan (Barmer and Jaisalmer Basins) – Tertiary and Mesozoic Rift Basins and Geodynamics
- 9.5 Deccan Syneclise (Narmada – Tapti Section) in Central India – Mesozoic Sediments and Basement Model
- 9.6 Offshore Exploration – Hydrocarbon Prospect
- 9.7 Vindhyan Basin, Central India and Singhbhum District – Groundwater Potential and Hydrocarbon Prospect
- 9.8 Upper and Lower Assam Shelf – Hydrocarbon Prospect and Geodynamics
- 9.9 Groundwater budgeting using GRACE Satellite Gravity Data
- 9.10 Mineral Exploration and Geodynamics
Chapter 10 Some Typical Environmental and Engineering Studies: Near Surface Geophysics
- 10.1 Introduction
- 10.2 Environmental Studies
- 10.3 Impact Craters- Lonar Lake in Deccan Trap Province
- 10.4 Effect of Solar Eclipse on the Earths Gravity Field – Allias Effect
- 10.5 Effects of Lightning on the Earth's Magnetic Field
- 10.6 Engineering Site Investigations
- 10.7 Archeological Site Investigations
Appendix: I Geological Time Scale
Appendix: II Some Important Events of Recent Periods (Pleistocene and Holocene)
Appendix: III Heat Flow Map of India
Appendix IV Seismic Zonation map of SAARC Countries-Pakistan and Bangla desh
Colour Photographs of All Chapters
Bibliography
Index
Biography
Dr. Dinesh Chandra Mishra obtained his Doctorate Degree from the Banaras Hindu University and worked at the Tata Institute of Fundamental Research in Mumbai. He later joined the National Geophysical Research Institute (NGRI) in Hyderabad, where he is still active as an Emeritus Scientist. He has carried out advanced geological research in many countries and guided many airborne magnetic and ground gravity surveys for exploration research in India and surrounding countries. As an expert, he has been involved with the preparation of gravity maps for geodynamics and resources exploration, integrated with other geophysical and geological information, such as satellite magnetic and gravity data. Dr. Mishra is the recipient of the National Mineral Award of the Ministry of Mines and Geology, the Business Development Award of the Council of Industrial and Scientific Research (CSIR) an the Decennial Award of the Indian Geophysical Union.
