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################# RECSEC 1.0 #################
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RECSEC creates the following from the tar bundle of 
records downloaded from IRIS for a single events:

a) cascade section of records (only BHZ) sorted based on epicentral distance;
b) scatter plot of maximum amplitude as a function of epicentral distance;
c) map of stations color-coded according to their epicentral distance.

NOTE:

1) Do not rename the downloaded tar file.
2) It is best to copy the tarball and this script into an empty directory;
   this prevents accidental overwrites, naming conflicts, etc;
3) Use the parameters under 'control parameters' for the purpose
   of your work.

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*) REQUIREMENTS:

1) FORTRAN 90+: 	usually included in generic 'gcc' bundles for UNIX;
2) SAC:	  	uses SAC mainly to filter records & remove instrument response;
3) GMT 4.X:	  	used for making plots; for other versions you may need to tweak
 		  	the script
4) TauP:		used to calculate P arrivals

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*) COMPILE:

To compile, simply cd to the 'bin' directory and run

		./compile

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*) COMPONENTS:

a) recsec:		main script
b) bin/:		directory containing source files and executables
	bin/circle.f	makes geographic circles at constant altitude
	bin/compile	script to compile fortran codes
	bin/minmax.f	finds attributes of max. amplitude log file
	bin/sac2gmt.f	converts binary SAC files to be piped into GMT
	bin/sacmax.f	sets plotting attributes for binary SAC files
	bin/sacsort.f	sorts SAC files based on epicentral distance and 
			extracts some attributes.
c) README:		documentation

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*) INPUT:

You only need the downloaded tarball from IRIS.

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*) OUTPUTS:

1) list.bhz:		list of record files

2) sort.out:		sorted list of records (based on distance)

3) sta.log:		list of stations and their coordinates
			this is a 4-column file (used for mapping):
			- station longitude
			- station latitude
			- max. amplitude
			- station name

4) max.log:		log of max. amplitudes for stations;
			this is a 4-column file:
			- record index in the original list [list.bhz]
			- epicentral distance (degrees)
			- max. amplitude (cm)
			- station name

5) NORESP files:	filtered records with removed instrument response;
			these are named as 
				NORESP.[index_in_original_list].[network].[station].BHZ.sac

6) plot.(ps,eps,jpg):	cascade record section

7) max.(ps,eps,jpg):	scatter plot of max. amplitudes at each station, 
			over epicentral distance

8) map.(ps,eps,jpg):	map of stations colored based on max. amplitude

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*) HOW TO USE:

1) Simply run:	./recsec [name_of_tarball]

2) Do not edit the displayed list.

3) Look at the three plots (especially max.*) and max.log to identify
   possible outliers. Document the corresponding station names and 
   index numbers in the original list.

4) Run the script again and this time change the identifier flag 
   (i.e., first column) of the outliers to '0'; this excludes them
   from the subsequent processing steps.

5) Repeat steps 3 an 4 if necessary.

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 A. Salaree
 Univ. of Michigan
 Oct 20, 2021