How to extract more information from geophysical data
Acquiring geophysics data is an expensive exercise so it’s vitally important to retrieve as much information as possible from the data to enhance the likelihood of exploration success. Starting with the basics, Adam Kroll, Senior Geophysicist at Frogtech Geoscience, reviews innovative techniques for gleaning maximum information from geophysical data in an article published on LinkedIn Pulse. The methods can be used for magnetics, gravity, elevation, electromagnetic grids and more.
In the article, Kroll looks at how to apply low, high and band pass filtering, for example to approximate depth to a source. Among his examples, he looks at the power spectrum of a grid to identify the filter lengths that will best enhance the signal from geological units of interest, using the MAGMAP extension in Geosoft Oasis montaj. MAGMAP has an option for interactive filtering that allows viewing the power spectrum and placing filter lengths in an interactive process.
Other types of enhancements, such as derivatives and trigonometric functions, are explained in mathematical terms. Once the relationship between the mathematics and geology is understood, a geophysics software package like Oasis montaj can be used to write formulas specifically designed to extract the desired geological content from geophysical data.
Kroll notes that any of the filters mentioned can be combined to produce a filter that will provide the information geologists require to interpret a region and identify the source bodies. He suggests testing several formulas to produce a filter that displays the geological feature of interest.
Read the full article on LinkedIn Pulse.