ANS: Ambient Noise Seismology

IMPORTANT NOTE: ans is added to gdp as a seismic module and the main updates/developments will be done in gdp (https://github.com/omid-b/gdp).

ans is a python wrapper for ambient noise seismology tasks and it has a GUI for easier configuration of ambient-noise seismology projects. In its backend, this package depends on Perl interpreter, GMT (Generic Mapping Tools), and SAC (Seismic Analysis Code) as well as python modules including ObsPy etc. ans is successfully tested on Python versions 3.6-3.11.

Pre-requisites

To run the gui (Debian Linux)

sudo apt install libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-render-util0
sudo apt-get install '^libxcb.*-dev' libx11-xcb-dev libglu1-mesa-dev libxrender-dev libxi-dev libxkbcommon-dev libxkbcommon-x11-dev

Convert to pdf file after plotting (Debian Linux)

sudo apt-get update
sudo apt-get -y install ghostscript
sudo apt install texlive-font-utils

Version 0.0.1

This version include all the necessary commands and tools required for generating Rayleigh wave (ZZ and RR cross-correlations) and Love wave (TT cross-correlation component) Empirical Green's Functions (EGFs). A brief description of most useful CLI commands is given below:

Workflow / Procedure

ans init <maindir>

Description: initialize ans project at project main directory i.e. <maindir>

ans config
ans config --maindir <maindir>

Description: open the program GUI to configure the ans project. Note: default <maindir> is current working directory

ans download stations

Description: download list of available stations at the given region boundary and dates that was previously set using the GUI. Datacenters, desired station components etc should also be set using '$ ans config'.

ans download metadata

Description: download station metadata files (xml file format) that will be used for instrument response removal and updating sac headers.

ans download mseeds

Description: main data acquisition module; download seismograms in mseed format

ans mseed2sac <mseeds_dir> <sacs_dir>

Description: convert mseed to sac files while applying the listed processing steps in project configuration mseed2sac tab (i.e., '$ ans config'). <mseeds_dir>: input mseed dataset directory <sacs_dir>: output sac files dataset directory

ans sac2ncf <sacs_dir> <ncfs_dir>

Description: process the input sacfiles in <sacs_dir> and output NCFs (noise cross-correlation functions) while applying the list of sac2ncf processes defined in project configuration file. Note: At this step it is necessary that all sac headers are updated and this can be done by either performing instrument response removal or adding "write headers" process to the list of processes.

ans ncf2egf <ncfs> <egfs_dir>

Description: <ncfs>: either path to the <ncfs_dir> (full stack EGFs) or an ASCII datalist containing a one-column data format list of paths to event directories (seasonal EGFs; e.g., "14001000000" i.e. 2014/01/01) <egfs_dir>: path to output stacked EGF