SES-02. Towards a Quantification of Uncertainty in Magnetic Maps and Models

Abstract
Magnetic maps and models are frequently utilized in a variety of applications including resource exploration, geological framework studies, and (increasingly) as a contributing layer or proxy in machine learning exercises. These maps and models do not traditionally include systematic assessment of uncertainty. For some applications (for example broad geological framework studies) detailed knowledge of uncertainty may not affect outcomes, but increasingly it is important to understand the reliability of the maps and models for their intended use. The primary sources of uncertainty for magnetic maps and models vary with wavelength. At the longest (global) wavelengths, where data from satellites are used, uncertainty relates to aspects of data assimilation and spherical harmonic modeling. At the shortest wavelengths uncertainty relates to original data distribution and quality. For example, uncertainty of magnetic maps over land (typically constructed with airborne surveys with regular flightline geometries) is systematically different than for those over water (typically constructed with marine trackline data with irregular geometries). We are developing ideas and methodology with the goal of providing cell by cell uncertainty for magnetic maps and models including our global EMAG2 data grid. The purpose of this presentation is to highlight preliminary studies in selected test areas including some model testing based on new data collection.