Seismic methods are commonly used to characterize reservoirs of all kinds. Micro-seismic events are an example of remote sensing of the reservoir.
In previous research, we reported on the distinction of seismic events that were originally clustered based on their distinct P- and S-waves. This involved a correlation technique in the frequency domain. In this postgraduate research project, we are going to tackle the following questions:
Fees and a stipend are provided by the Physical Acoustics Lab, thanks to the generous support of the Schlumberger’s Gould Research Center, Cambridge, UK.
Resonance Ultrasound Spectroscopy (RUS) uses the normal modes of an oscillating body to determine its elastic parameters. It allows the complete tensor to
be determined from a single measurement.
It fi ts an experimental gap between low frequency stress-strain measurements and high frequency time of flight experiments and deals with frequencies at the high end of those relevant to geophysical applications. It is a nondestructive method that can be used on small, rare or hard to obtain samples.
Dear All,
A lot has happened since our last posting. Thomas Blum is a Dr. Blum now, and oh, yes: The Physical Acoustics Lab moved from Boise, Idaho, to the University of Auckland in New Zealand!
#!/bin/sh
## this is the flow of processing steps for two purposes: 1) we add
## data to our database for research purposes. 2) we transform the ZIP
## files to the format IRIS wants them
# First step: your zip files collected in the field on date
# $servicedate are in
# /pal/fieldcamp/2011/passive_seismic/data/$servicedate/raw (and the
# Service Forms should digitized and stored in the same directory)
. /opt/antelope/5.1-64/setup.sh # run the antelope setup for the path
# to antelope functions.
# Our network code is:
NET=XN
# Our database we call:
dbname=neal_HS
servicedate=20120405
########### setup to correct directory structure ##########################
mkdir $servicedate/mseed # location for mseed files after extracting
# with unchunky (in rt2ms)
mkdir $servicedate/logs # location for *.log, *.err, and *.run files
mkdir $servicedate/day_volumes # day-long miniseed files after running
# miniseed2days. It is these files you
# FTP to IRIS.
###########################################################################
# this next section only necessary the first time you process data:
# copy the needed files to correct directory
#/bin/cp -f /pal/fieldcamp/2011/passive_seismic/codes/batchfile.pf .
# convert batch to parameter file:
#batch2par batchfile.pf > par_file_tmp.pf
# EDIT THE refstrm COLUMN to all 1s:
#sed 's/rs250spsrs/1/' par_file_tmp.pf > parfile.pf
#rm -rf par_file_tmp.pf
##########################################################################
# make a list of all zip files in the directory:
ls $servicedate/raw/*.ZIP > list.file
# convert the zip files from the reftek (rt) to miniseed (ms):
rt2ms -F list.file -p parfile.pf -o $servicedate/mseed/ -R -L
# so the next service date can be processed, make sure that:
rm -rf list.file
##########################################################################
# The next section is to convert the log files to mseed LOG files:
# log2miniseed needs some parameters changed from the default, before
# running:
/bin/cp -f $ANTELOPE/data/pf/log2miniseed.pf .
# this makes sure the LOG files get into the proper day_volumes
# directory to go with the data:
sed "/wfname/ c wfname $servicedate/day_volumes/%{sta}/%{sta}.%{net}.%{loc}.%{chan}.%Y.%j" log2miniseed_tst.pf
mv -f log2miniseed_tst.pf log2miniseed.pf
# script to convert log files to miniseed, for all log files in the
# mseed directory:
for file in `ls $servicedate/mseed/*log`
do
# first, we need establish the serial number of each file:
srnmb=`echo $file | awk -F . '{print $6}'`
# then, map serial number to station name:
case $srnmb
in
9477) log2miniseed -a -n XN -s PS01 $file;;
9261) log2miniseed -a -n XN -s PS02 $file;;
92C3) log2miniseed -a -n XN -s PS03 $file;;
984E) log2miniseed -a -n XN -s PS04 $file;;
9559) log2miniseed -a -n XN -s PS05 $file;;
9294) log2miniseed -a -n XN -s PS06 $file;;
956E) log2miniseed -a -n XN -s PS07 $file;;
9924) log2miniseed -a -n XN -s PS08 $file;;
9144) log2miniseed -a -n XN -s PS09 $file;;
9098) log2miniseed -a -n XN -s PS10 $file;;
929B) log2miniseed -a -n XN -s PS11 $file;;
esac
done
# note that PS11 changed RT130s early in the project!
##########################################################################
# move the raw log and err files out of the mseed directory:
mv $servicedate/mseed/*log $servicedate/mseed/*err $servicedate/logs/
# to build the antelope database do the following. DON'T DO THIS, if you
# are adding data to an existing database:
#dbbuild -b $dbname ./batchfile.pf >& dbbuild.out
# use "dbe $dbname" to look at the database to make sure it is sound
# link the waveforms to day_volumes for IRIS:
miniseed2days -Du -d $dbname -w "$servicedate/day_volumes/%{sta}/%{sta}.%{net}.%{loc}.%{chan}.%Y.%j" $servicedate/mseed/ >& msd2days.out
################################################################################
# the rest is just checking the integrity of the database:
# asign calibration values from the calibration table:
dbfix_calib $dbname
# verify the correlation of your data and database:
dbversdwf -tu $dbname
dbverify -tj $dbname >& dbverify.out
# create the dataless SEED volume (ONLY ONCE!). The dataless SEED volume, often
#referred to as a "dataless", contains the meta-data describing the
#station and instrumentation of your experiment. To generate the
#dataless SEED volume, run mk_dataless_seed, which builds the dataless
#from the contents of your experiment's database. You will submit this
#file along with the waveforms to PASSCAL. (should be named with the
#*current* date):
#outputfile=$NET.`date +%y`.$dbname.`date +%Y%j%H%M`.dataless
# make the dataless SEED volume:
#mk_dataless_seed -v -o $outputfile $dbname
# check the structure of the dataless SEED with
#seed2db -v $outputfile