Three‐dimensional magnetotelluric inversion of large data sets: Case study of Pasfield Lake (Saskatchewan) for mineral exploration

As the combination of high-intensity synchrotron sources and area detectors allows collection of large data sets in a much shorter time span than previously possible, the use of open helium gas-flow systems is much facilitated. A flow system installed at the SUNY X3 synchrotron beamline at the National Synchrotron Light Source has been used for collection of a number of large data sets at a temperature of ∼16 K. Instability problems encountered when using a helium cryostat for three-dimensional data collection are eliminated. Details of the equipment, its temperature calibration and a typical result are described.

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Inversion for magnetic anomalies of arbitrary three‐dimensional bodies

Geophysics ◽

10.1190/1.1442779 ◽

1990 ◽

Vol 55 (10) ◽

pp. 1321-1326 ◽

Cited By ~ 30

Author(s):

X. Wang ◽

R. O. Hansen

Keyword(s):

Three Dimensional ◽

Large Data ◽

Magnetic Anomalies ◽

Large Data Sets ◽

Data Sets ◽

Inversion Algorithm ◽

Geologic Model ◽

Profile Inversion ◽

Inversion Techniques ◽

Medicine Lake

Two‐dimensional (profile) inversion techniques for magnetic anomalies are widely used in exploration geophysics: but, until now, the three‐dimensional (3-D) methods available have been restricted in their geologic applicability, dependent upon good initial values or limited by the capabilities of existing computers. We have developed a fully 3-D inversion algorithm intended for routine application to large data sets. The algorithm based on a Fourier transform expression for the magnetic field of homogeneous polyhedral bodies (Hansen and Wang, 1998), is a 3-D generalization of CompuDepth (O’Brien, 1972). Like CompuDepth, the new inversion algorithm employs thespatial equivalent of frequency‐domain autoregression to determine a series of coefficients from which the depths and locations of polyhedral vertices are calculated by solving complex polynomials. These vertices are used to build a 3-D geologic model. Application to the Medicine Lake Volcano aeromagnetic anomaly resulted in a geologically reasonable model of the source.

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Three-dimensional Interactive Data Language pole figure visualization

Powder Diffraction ◽

10.1154/1.2204955 ◽

2006 ◽

Vol 21 (2) ◽

pp. 102-104 ◽

Cited By ~ 3

Author(s):

Colleen S. Frazer ◽

Mark A. Rodriguez ◽

Ralph G. Tissot

Keyword(s):

Pole Figure ◽

Three Dimensional ◽

Large Data ◽

Peak Height ◽

Large Data Sets ◽

Data Sets ◽

Interactive Data Language ◽

Area Detector ◽

Position Sensitive ◽

Interactive Data

The Interactive Data Language has been used to produce a software program capable of advanced three-dimensional visualizations of pole figure and θ-2θ data. The data can also be used to calculate quantitative properties such as strain level and to minimize the peak-height texture effects in individual θ-2θ scans. The collection of the large data sets necessary for the analyses is facilitated by use of a position sensitive detector or area detector.

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Wavelet Compression of Three-Dimensional Time-Lapse Biological Image Data

Microscopy and Microanalysis ◽

10.1017/s1431927605050014 ◽

2005 ◽

Vol 11 (1) ◽

pp. 9-17 ◽

Cited By ~ 1

Author(s):

H. Narfi Stefansson ◽

Kevin W. Eliceiri ◽

Charles F. Thomas ◽

Amos Ron ◽

Ron DeVore ◽

...

Keyword(s):

High Speed ◽

Three Dimensional ◽

Image Data ◽

Large Data ◽

Time Lapse ◽

Large Data Sets ◽

Multidimensional Data ◽

Data Sets ◽

Optical Sectioning ◽

Dynamic Events

The use of multifocal-plane, time-lapse recordings of living specimens has allowed investigators to visualize dynamic events both within ensembles of cells and individual cells. Recordings of such four-dimensional (4D) data from digital optical sectioning microscopy produce very large data sets. We describe a wavelet-based data compression algorithm that capitalizes on the inherent redunancies within multidimensional data to achieve higher compression levels than can be obtained from single images. The algorithm will permit remote users to roam through large 4D data sets using communication channels of modest bandwidth at high speed. This will allow animation to be used as a powerful aid to visualizing dynamic changes in three-dimensional structures.

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