Gravity Method Tutorial Series

A comprehensive, hands-on computational geophysics tutorial series using Python and Jupyter Notebooks for students, lecturers, and geoscientists.

Author: Dicky Ahmad Zaky
Affiliation: Geophysical Engineering Department, Universitas Pertamina

📚 Tutorial Overview & Curriculum

This series guides students step-by-step from fundamental potential field physics to advanced 2D mapping and non-linear numerical inversion:

#	Notebook	Key Topics & Geoscientific Concepts
01	`Tutorial 1 - Forward Modeling Gravity Anomaly.ipynb`	Analytical forward modeling of buried spheres; effect of depth, radius, and density contrast on vertical gravity anomalies ($\Delta g$).
02	`Tutorial 2 - Spectral Analysis of Gravity Anomaly.ipynb`	1D Fast Fourier Transform (FFT), wavenumber spectra ($\ln A$ vs $k$), depth estimation via spectral slopes, cut-off wavenumber ($k_c$).
03	`Tutorial 3 - Gravity Anomaly Separation.ipynb`	Separation of regional-residual gravity fields; Moving Average filter with spectral cut-off window ($N = 2\pi / (k_c \Delta x)$); 1st, 2nd, and 3rd order polynomial trend surface fitting; RMSE benchmarking against synthetic ground truth.
04	`Tutorial 4 - Gravity Anomaly Mapping.ipynb`	2D survey grids, Complete Bouguer Anomaly (CBA) contouring, shaded relief / hillshade illumination, edge enhancement filters: First Horizontal Derivative (FHD) and Second Vertical Derivative (SVD) zero-contour fault detection.
05	`Tutorial 5 - Gravity Inverse Modeling.ipynb`	1D Non-linear least squares inversion (`scipy.optimize.curve_fit` / TRF algorithm); parameter bounds and uncertainty quantification (covariance matrix); solving non-uniqueness / mass equivalence with density priors.

The tutorials are designed to run cleanly using standard scientific Python packages:

pip install numpy scipy matplotlib

To run the notebooks:

jupyter notebook

Self-Contained & Synthetic: Every notebook generates its own synthetic ground truth dynamically—no external proprietary data files or fragile paths required.
Geoscientific Continuity: Parameters from earlier notebooks (e.g., cutoff wavenumbers from Tutorial 2, sphere geometries from Tutorial 1) carry forward naturally into subsequent tutorials.
Guided Exercises: Each tutorial concludes with reflective conceptual questions and coding exercises designed for classroom assessment or independent study.