Three-dimensional Geologic Structures from Inversion of Gravity Anomalies
Author: Charles Alvin Hinson
Publisher:
Published: 1976
Total Pages: 198
ISBN-13:
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Quantification of Gravity Anomalies for Subsurface Geological Structures using Variable Density Contrast
Author: Vishnubhotla Chakravarthi
Publisher: Springer
Published: 2015-09-15
Total Pages: 175
ISBN-13: 9783642288562
DOWNLOAD EBOOKComputer based algorithms to analyze gravity anomalies for subsurface structures have gained momentum in the search of natural resources. The enormous progress since then, however, led to the development of new interpretational techniques with increasing accuracy to analyze the gravity anomalies. The fact that variable density models yield more reliable interpretations has paved the way for developing new analytical tools to analyze gravity anomalies. In this book, the parabolic density function which unambiguously describes the density-depth dependence of sedimentary rocks is used to design new algorithms and relevant GUI based JAVA programs to analyze the gravity anomalies of subsurface geological structures. Although the terms “modeling” and “inversion” are used more or less synonymously to refer to various interpretation strategies of gravity anomalies, criteria has been formulated and followed to design modeling and inversion strategies of gravity anomalies. Accordingly, automatic inversion algorithms coupled with relevant computer codes to analyze the gravity anomalies due to 2-D and 2.5-D fault structures described with both planar and non-planar fault planes are presented. Automatic techniques based on modeling and inversion principles to analyze the gravity anomalies due to 2-D and 2.5-D sedimentary basins even when the profile of interpretation fails to bisects the strike length of the target are presented with related software. Automatic modeling and inversion techniques for the analysis of measured gravity anomalies due to 3-D sedimentary basins are presented. Also new is the automatic determination of regional gravity background in case of inversion algorithms. The highlight of the book is that, in each case, the robustness is demonstrated with both synthetic and real field gravity anomalies. Thus this book is very useful to academicians, researchers and field geophysicists. To the best of my knowledge no comprehensive book is available to address the issues described above and hence this volume would certainly attract the market.
Software Development for a Three-dimensional Gravity Inversion and Application to Study of the Border Ranges Fault System, South-Central Alaska
Author: Rolando Cardenas
Publisher:
Published: 2011
Total Pages: 118
ISBN-13:
DOWNLOAD EBOOKThe Border Ranges Fault System (BRFS) bounds the Cook Inlet and Susitna Basins, an important petroleum province within south-central Alaska. A primary goal in the research is to test several plausible models of structure along the Border Ranges Fault System using a novel three-dimensional inversion utilizing gravity and magnetic data, constrained with other geophysical, borehole and surface geological information. This research involves the development of inversion modeling software using a Borland C++ compiler as part of the Rapid Application Development (RAD) Studio. The novel inversion approach directly models known geology, and a priori uncertainties on the geologic model to allow researchers to compare alternative interpretations. This technique to evaluate three-dimensional structure in regions of extremely complex and poorly known geology can be applied in other studies of energy resources. The software reads an ASCII text file containing the latitude, longitude, elevation, and Free Air anomalies of each gravity station as well as known gridded surface files of known topography and subsurface units. The contributions of each node in the grid are computed in order to compare the theoretical gravity calculations from a forward model to the gravity observations. The computation of solutions to the linearized inversion yields a range of plausible densities. The user will have the option of varying the body proportions or densities to observe changes in gravity
U.S. Geological Survey Professional Paper
Author:
Publisher:
Published: 1902
Total Pages: 222
ISBN-13:
DOWNLOAD EBOOKGeophysical Inversion
Author: J. Bee Bednar
Publisher: SIAM
Published: 1992-01-01
Total Pages: 472
ISBN-13: 9780898712735
DOWNLOAD EBOOKThis collection of papers on geophysical inversion contains research and survey articles on where the field has been and where it's going, and what is practical and what is not. Topics covered include seismic tomography, migration and inverse scattering.
Gravity Interpretation
Author: Wolfgang Jacoby
Publisher: Springer Science & Business Media
Published: 2009-02-01
Total Pages: 413
ISBN-13: 3540853294
DOWNLOAD EBOOKGravity interpretation involves inversion of data into models, but it is more. Gravity interpretation is used in a “holistic” sense going beyond “inversion”. Inversion is like optimization within certain a priori assumptions, i.e., all anticipated models lie in a limited domain of the a priori errors. No source should exist outside the anticipated model volume, but that is never literally true. Interpretation goes beyond by taking “outside” possibilities into account in the widest sense. Any neglected possibility carries the danger of seriously affecting the interpretation. Gravity interpretation pertains to wider questions such as the shape of the Earth, the nature of the continental and oceanic crust, isostasy, forces and stresses, geol- ical structure, nding useful resources, climate change, etc. Interpretation is often used synonymously with modelling and inversion of observations toward models. Interpretation places the inversion results into the wider geological or economic context and into the framework of science and humanity. Models play a central role in science. They are images of phenomena of the physical world, for example, scale images or metaphors, enabling the human mind to describe observations and re- tionships by abstract mathematical means. Models served orientation and survival in a complex, partly invisible physical and social environment.
Applications of Gravity Anomalies in Geophysics
Author: Henglei Zhang
Publisher: Frontiers Media SA
Published: 2024-01-26
Total Pages: 151
ISBN-13: 2832543553
DOWNLOAD EBOOKKnowledge of the density of the subsurface of a planet is crucial in determining its interior structure, and one can estimate the average bulk crustal density directly using the admittance between topography and gravity, which has been successfully used for the Moon and is being extended to Mars. The interpretation of gravity data is commonly done by computation of a gravity anomaly (GA) by correcting the raw data for a number of factors that impact the gravity field. Depending on the target science, different types of GA can be computed, the interpretation of which have been widely employed in geophysics to explore the interior of the Earth and other planets, through applications in airborne gravity, near-surface geophysics, regional geophysics, and planetary geophysics. Yet how to extract a great variety of information from GAs for applications in geophysics entails further investigation. Over the decades, remarkable progress has been made to extract information from GAs identified from data. For instance, a series of 3D inversion algorithms facilitates the extraction of the subsurface density distribution. With the improved processing based on dense gravity observations that yield high precision and high resolution GAs, more detailed geological information can be unveiled. When using the admittance between topography and gravity to estimate the crustal density, it is essential to identify what kinds of GAs to be used, such as Bouguer gravity or free-air gravity. Also, what appropriate approaches to scrutinize the applications of GAs in various case studies (e.g., calculating the geoid and estimating the elastic thickness) need to be decoded.
Cratonic Basin Formation
Author: M. C. Daly
Publisher: Geological Society of London
Published: 2018-12-03
Total Pages: 373
ISBN-13: 1786203960
DOWNLOAD EBOOKCratonic basins are large, distinctive features of the continental crust. They are preferentially developed on thick continental lithosphere, are typically sub-circular in shape and subside over periods of hundreds of millions of years. They are also endowed with significant resources. However, in spite of their location in continental interiors and often well-known geology, the subsidence driving mechanism and tectonic setting of these basins remains controversial. This volume presents both lithospheric and basin scale datasets acquired specifically to interrogate the tectonic process of cratonic basin formation. Focused on the Silurian to Triassic Parnaíba cratonic basin of Brazil, the papers discuss the results of a multidisciplinary basin analysis project comprising new geophysical, geological and geochemical data. This unique dataset enables the characterization of the lithospheric crust and mantle beneath the Parnaíba Basin, constrains the detailed evolution of the basin itself, and enables comparisons with cratonic basins globally. Several convergent themes emerge providing new and powerful constraints for models of the driving mechanisms of these enigmatic basins.
Journal
Author: Canadian Society of Exploration Geophysicists
Publisher:
Published: 1990
Total Pages: 792
ISBN-13:
DOWNLOAD EBOOKThe Utility of Regional Gravity and Magnetic Anomaly Maps
Author: William J. Hinze
Publisher:
Published: 1985
Total Pages: 480
ISBN-13:
DOWNLOAD EBOOKThe subjects of the papers that make up the volume vary from the preparation of national maps to examples of the many uses of regional maps. The anomalities that are discussed range in areal dimension from hundreds of kilometers to tons of meters. The majority of the papers illustrate the utility of the maps in mapping structures and lithologic variations wirhin the continenetal crust, the configuration of the crystalline basements rocks, zones of crustal weakness, distribution of extrusive and intrusive igneous rocks and the geometry of sedimentary basins. Most cases are drawn from the United States and Canada, but examples from Europe, Africa, South America and Asia are included.
