Tutorial¶
Quote
You can’t blame gravity for falling in love
― Albert Einstein
Preface¶
This tutorial provides a basic working concept of IGMAS+ when used to investigate gravity and magnetic fields, including all aspects that need to be considered when starting an IGMAS+ project. It is intended to bridge general textbook knowledge on gravity modelling with the specific “how-to” information given in other chapters. Hence, it provides both key words from the gravity research field (without repeating textbook contents) and definitions for IGMAS+ specific terms which can be further looked up in the documentation.
Potential fields¶
IGMAS+ calculates both fields of the potential methods: the gravity field and the magnetic field. It is user friendly and allows very fast calculations. In this tutorial we focus on the explanations with gravity field modelling. The calculation of the magnetic field of geological bodies is equivalent: one replaces the rock parameter "density" by the rock parameter "magnetic susceptibility" or, where it is necessary, by the "remanent magnetization" of rocks. All explanations are valid for modelling with both fields.
Chapters¶
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Explore how deviations from Earth's normal gravity field reveal subsurface density structures, the challenge of non-uniqueness, and how IGMAS+ addresses it using independent constraints.
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Learn how to construct 3D density or susceptibility models in IGMAS+, define bodies and voxels, assign model parameters, and manage stations - core steps for reliable gravity modelling.
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Understand how IGMAS+ calculates gravity and magnetic field components and gradients, accounts for modelling shifts, and handles edge effects for precise results.
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Get guidance on how to fit observed gravity data using IGMAS+, differentiate between Bouguer and Free Air anomalies, and utilize global gravity datasets effectively.