# Gravity Modelling by Using N-Sided Polyhedrons

## Description

This repository contains scripts and artificial gravity datasets used and explained in paper "Gravity Modelling of Sedimentary Basins by Using N-Sided Vertical Polyhedrons" by Nedim Gökhan AYDIN and Turgay İŞSEVEN. The scripts and the data are explained below. -intlog5a.m is the MATLAB adaptation of the FORTRAN scripts given by Smith (2000). -gprism.m calculates the gravity contribution of a polyhedron in space. -VoronoiIterations.m applies modelling process for given gravity anomalies, data points and parameters. -The two artificial gravity data (faulty_grav.mat and basin_grav.mat) are 500x500 matrixes for two different underground structures. *The scripts require VoronoiLimit.m function from MATLAB File Exchange to compute Voronoi diagrams for limited area (Sievers, 2023).

## Files

## Steps to reproduce

This pack contains scripts for the iterative modelling approach of gravity anomalies explained in "Gravity Modelling of Sedimentary Basins by Using N-Sided Vertical Polyhedrons" paper. Reproduction steps are given below. - All the scripts and gravity data to be studied should be in the same directory. - To start the iterative process, open "VoronoiIterations.m" for editing. - Under "parameters" header you can define upper and lower depth boundaries for polyhedrons (Ubound, Lbound), density (drho), iterations number (ITNO) and convergence coefficient (INCON). - Under "load data" header you can set the limits for the datasets and select the input data file. Data should be assigned to the parameter "input". - Under "load data" header you can also load the data points in surface and assign it to "input_pts" parameter. - The default values of each parameter are given in the script. Data points are generated randomly in default size. - After definitions are complete, Run the script. - The status of the modelling process will be prompted on Command Window and the results will be shown in a figure [input data and data points, calculated anomalies; depth model, difference between input and calculated]. Some important variables that could be of use after calculations are done: - zz: calculated depth model in matrix form. - RMS: contains the RMS misfit achieved after each iteration. - polies: contains polyhedron coordinates and individual gravity anomalies of each. - Zlist: upper boundaries of the polyhedrons after each iteration.

## Institutions

## Categories

## Funding

Bilimsel Araştırma Projeleri Birimi, İstanbul Teknik Üniversitesi

MDK-2020-42703