On Reproducibility of Papers: Magnetic Alignments

Editor’s note: there’s an here update to this post.

From times to times, I like to reproduce papers that will ease my life at the Geological Survey of Brazil. However, I usually stumble exactly in reproducibility issues – lack of the implementation code, parameters or even the shown dataset – and that’s exactly what happened when I tried to reproduce the paper “Towards the automated analysis of regional aeromagnetic data“, from Holden et al.

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Color Quantization for Ternary Maps with GDAL

One of the works the Geophysicist usually do at the Geological Survey of Brazil is the correlation between geophysics and geology for geological mapping. This task is done through the use of gammaspectrometric data – and, since its penetration (skin depth) is very low, the data is deeply correlated to the surface geology. By assigning colors to Potassium, Thorium and Uranium values, it is possible to generate what is known as ‘ternary map’ – pretty much a geological map. As this map is usually shown in RGB, the range of colors is about 16 million – and this is a issue for interpretation. In this post, we discuss a method to reduce it to 27 colors.

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GeoFront: An Initial Concept

Note: Me and my coworkers are (very slowly) working on this! Check on Github! We hope to have some proof-of-concept in a few months time.

Since I joined the Geological Survey of Brazil, I’ve had some issues with geophysical data processing softwares – mainly for those who are designed for grav/mag/gamma datasets. The softwares lacks either usability (UX Experience) or lacks performance. The GeoFront (a wordplay with the ‘Neon Genesis Evangelion’ series) comes to solve both of this problem while providing a new model for data processing.

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