Analyses of crustal structure from bandpass and directionally filtered potential-field data: an example from western Canada

2001 ◽  
Vol 38 (6) ◽  
pp. 953-961 ◽  
Author(s):  
Hugh D Geiger ◽  
Frederick A Cook
Keyword(s):  
Potential Field ◽  
Field Data ◽  
Rocky Mountain ◽  
Western Canada ◽  
Potential Field Data ◽  
Directional Filtering ◽  
Crustal Structures ◽  
Depth Extent ◽  
Lower Crustal ◽  
Dextral Strike Slip

Application of bandpass and directional filtering to potential-field data in northwestern Canada allows separation of anomalies due to northwest-oriented upper crustal sources that are associated with Cordilleran structures from anomalies due to northeast-oriented lower crustal sources that are primarily associated with Precambrian Shield rocks. In northeastern British Columbia, northeast-trending lower crustal structures of the Canadian Shield as represented in the gravity patterns appear to project west of the Tintina fault – Northern Rocky Mountain Trench at about 56°N. About 400–500 km farther north, the Tintina fault may penetrate into the lithospheric mantle. It is, thus, likely that the depth extent of the Tintina fault rises southward into the crust, as dextral strike-slip motion is transformed into contractional structures of the southern Cordillera.

scholarly journals Deep Crustal Structures Interpreted from Potential Field Data along the Deep Seismic Sounding Transect across Olympic Dam, South Australia

2013 ◽  
Vol 2013 (1) ◽  
pp. 1-4
Author(s):  
Irena Kivior ◽  
David Boyd ◽  
David Tucker ◽  
Stephen Markham ◽  
Francis Vaughan ◽  
...  
Keyword(s):  
Potential Field ◽  
Field Data ◽  
South Australia ◽  
Deep Seismic Sounding ◽  
Potential Field Data ◽  
Seismic Sounding ◽  
Crustal Structures ◽  
Olympic Dam

Deep crustal structures interpreted from potential field data along deep seismic sounding transects in Australia

2015 ◽  
Vol 55 (2) ◽  
pp. 450
Author(s):  
Irena Kivior ◽  
David Boyd ◽  
David Tucker ◽  
Stephen Markham ◽  
Francis Vaughan ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Potential Field ◽  
Field Data ◽  
Gravity Data ◽  
Sedimentary Basins ◽  
Deep Seismic Sounding ◽  
Magnetic Data ◽  
Potential Field Data ◽  
Seismic Sounding ◽  
Crustal Structures

Energy spectral analysis techniques have been applied to magnetic and gravity data acquired across the Olympic Dam cratonic area in Australia and sedimentary basins along the Equatorial Margin of Brazil. Analysis has been conducted along two Deep Seismic Sounding lines (DSS) acquired by Geoscience Australia. There is a good correlation between interfaces found in this analysis and structures interpreted from the seismic data. Interpretation of gravity data using energy spectral analysis along the DSS survey lines show a number of deep crustal structures are evident, including the Moho which was detected using gravity data, while similar analysis of the magnetic data show indications of the Curie isotherm. In addition, the analysis was extended away from the seismic lines to detect many deep crustal horizons and structures at considerable distances from the DSS lines. The results obtained from energy spectral analysis across this area in Australia encouraged the application of this technique on the Equatorial Margin of Brazil, where the potential field data is of much lower resolution. This suggests that a much wider application of this approach could be highly valuable to investigate the deep structure under other sedimentary basins and to assist heat flow studies.

An improved approach for detecting the locations of the maxima in interpreting potential field data

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Luan Thanh Pham ◽  
Ozkan Kafadar ◽  
Erdinc Oksum ◽  
Ahmed M. Eldosouky
Keyword(s):  
Potential Field ◽  
Field Data ◽  
Potential Field Data

Adaptive sampling of potential-field data: A direct approach to compressive inversion

Geophysics ◽  
2014 ◽  
Vol 79 (1) ◽  
pp. IM1-IM9 ◽  
Author(s):  
Nathan Leon Foks ◽  
Richard Krahenbuhl ◽  
Yaoguo Li
Keyword(s):  
Potential Field ◽  
Adaptive Sampling ◽  
Field Data ◽  
Computational Cost ◽  
Large Field ◽  
Magnetic Data ◽  
Data Sampling ◽  
Data Types ◽  
Data Set ◽  
Potential Field Data

Compressive inversion uses computational algorithms that decrease the time and storage needs of a traditional inverse problem. Most compression approaches focus on the model domain, and very few, other than traditional downsampling focus on the data domain for potential-field applications. To further the compression in the data domain, a direct and practical approach to the adaptive downsampling of potential-field data for large inversion problems has been developed. The approach is formulated to significantly reduce the quantity of data in relatively smooth or quiet regions of the data set, while preserving the signal anomalies that contain the relevant target information. Two major benefits arise from this form of compressive inversion. First, because the approach compresses the problem in the data domain, it can be applied immediately without the addition of, or modification to, existing inversion software. Second, as most industry software use some form of model or sensitivity compression, the addition of this adaptive data sampling creates a complete compressive inversion methodology whereby the reduction of computational cost is achieved simultaneously in the model and data domains. We applied the method to a synthetic magnetic data set and two large field magnetic data sets; however, the method is also applicable to other data types. Our results showed that the relevant model information is maintained after inversion despite using 1%–5% of the data.

Application of Potential Field Data to Interpretation of the Basement Rock Structure at Bukit Bunuh, Perak

2010 ◽  
Author(s):  
M. Shyeh Sahibul Karamah ◽  
M. N. Khairul Arifin ◽  
Mohd N. Nawawi ◽  
A. K. Yahya ◽  
Shah Alam
Keyword(s):  
Potential Field ◽  
Field Data ◽  
Basement Rock ◽  
Potential Field Data ◽  
Rock Structure

Crustal structure of the Valhalla complex, British Columbia, from Lithoprobe seismic-reflection and potential-field data

1990 ◽  
Vol 27 (8) ◽  
pp. 1048-1060 ◽  
Author(s):  
David W. S. Eaton ◽  
Frederick A. Cook
Keyword(s):  
Heat Flux ◽  
North American ◽  
Seismic Reflection ◽  
Surface Heat Flux ◽  
Field Data ◽  
High Surface ◽  
Surface Heat ◽  
Upper Crust ◽  
Potential Field Data ◽  
Lower Crustal

The Valhalla complex, situated in the Omineca crystalline belt in southeastern British Columbia, is a Cordilleran metamorphic core complex bordering the suture zone between Quesnellia and North American rocks. The region is tectonically interposed between a convergent plate margin along Canada's west coast and the stable North American craton, and is characterized by a crustal thickness of ~ 35 km, high surface heat flux, and elevated lower crustal electrical conductivity. In this study, Lithoprobe deep-crustal seismic-reflection data, potential-field data, and geological constraints have been used to gain a better understanding of crustal structure in the vicinity of the Valhalla complex. Analysis of Bouguer gravity and total-field aeromagnetic data indicates that mafic oceanic rocks and various syn- and post-accretionary granitoid plutonic rocks are not major constituents of the upper crust underlying the complex. The seismic data reveal a moderately reflective upper crust and image several fault zones, including a very high amplitude, west-dipping reflection that is interpreted as a significant Late Cretaceous or Paleocene thrust fault. The fault-zone reflectivity may be related to compositional heterogeneity and (or) seismic anisotropy associated with mylonites. The lower crust appears to be nonreflective, in contrast with other areas of high surface heat flux and elevated lower crustal conductivity. Taken together, the various data show that the Valhalla complex is likely cored by North American metasedimentary rocks and reveal features related to the Jurassic to Paleocene compressional fabric, which has been largely overprinted at the surface by subsequent Eocene extension.

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