2D Talwani Modelling - MATLAB Scripts

This dataset contains a MATLAB function to compute gravit anomaly of a given polygonal shape by using Talwani Method (Talwani & Ewing, 1959), along with a random data generator and an example script to explain the workflow. The three scripts within the pack are as follows:

- talwm.m : Main function to compute the gravity anomalies of a given 2D polygon. The gravity anomalies over (sx,sz) points are calculated resulting from a polygon whose coordinates are given in [px,pz] matrix and has a density contrast of ro. ( g = talwm(sx, sz, [px,pz], ro); )

- perlin.m : A function to create random data using Perlin Noise (Perlin, 2002). The function creates a matrix M for given size (m x n). The smoothness and center-orientation (i.e. maximum values in the center) can be modified. ( a = perlin([1,201], 0.8, 4); )

- talwani_modelling_example.m : a script showing the utilization of the talwm.m function. Subsurface is defined using polygonal areas with vertices. Their gravity anomalies are computed separately by using talwm.m. For testing, a random gravity anomaly is created using perlin.m function. The polygons are manually modified to match the random gravity anomalies with the computed ones. The script finally visualizes the gravity anomalies and the model in a single figure.

For real data cases, observed anomalies can be input into the script instead of using Perlin noise and subsurface units can be defined as needed. Building a semi-iterative procedure to match observed-computed anomalies is also possible.