- Date: 2006 (process 1 of 16)
-
The data files were transferred from the acquisition computer via a USB thumb drive. The first step is to check the navigation recorded in the *.gps file for each line of acquisition. I ran an AWK script which extracted ONLY the navigation information recorded in each individual GPS data file. This information is written to a comma-delimited ANSI text file. (* refers to the line name, which for this day are l7f1, l8f1, f9l1, f10l1, l10f2, l11f1, l12f1, l13f1, l14f1, l15f1, l16f1, l17f1, l18f1, and l19f1).
AWK script awkit_tmp:
BEGIN {
FS=","
}
{
FS= ","
ARGC = 2
if ($1=="$GPRMC") {
gpstime = $2
hr = substr($2,1,2)
min = substr($2,3,2)
sec = substr($2,5,2)
latdeg = substr($4,1,2)
latmin = substr($4,3,6)
londeg = substr($6,2,2)
lonmin = substr($6,4,6)
declat = latdeg + (latmin/60)
declon = (londeg + (lonmin/60)) * -1
date = $10
day = substr($10,1,2)
month = substr($10,3,2)
year = substr($10,5,2)
printf("%8.6f, %8.6f, %s:%s:%s, %s, %s\n",declon, declat, hr, min, sec, date, ARGV[2])
}
}
This AWK script was initialized by "doawk" - shell script run under CYGWIN (UNIX like environment that runs under Windows):
files=`ls *.gps | cut -d. -f1`
for file in $files
do
awk -f awkhold $file.gps $file >> resnav_jd250.txt
done
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- Date: 2006 (process 2 of 16)
-
This text file (resjustnav_jd250.txt) was loaded as an event them into ArcView 3.3. Displaying these points allowed me to flag the sections of bad navigation.
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- Date: 2006 (process 3 of 16)
-
An ANSI text file containing the ship's navigation and fathometer information was transferred from the ship's system using a thumb drive.
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- Date: 2006 (process 4 of 16)
-
The ship's text navigation file was reformatted using an AWK script into a comma-delimited ANSI text file suitable for loading in the GIS. AWK script "awknav":
{
shipdate = $1
gpstime = $2
latdeg = substr($5,1,2)
latdecmin = $6
declat = latdeg + (latdecmin/60)
londeg = substr($7,1,3)
londecmin = $8
declon = -1 * (londeg + (londecmin/60))
depmeters = $10 printf("%s, %s, %9.6f, %9.6f, %s\n",shipdate, gpstime, declat, >declon, depmeters)
}
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- Date: 2006 (process 5 of 16)
-
I was than able to extract each segment of reformatted ship's navigation that corresponded to the time gaps within my resistivity navigation.
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- l7f1_gap1.txt
- l7f1_gap2.txt
- l8f1_gap1.txt
- l8f1_gap2.txt
- Date: 2006 (process 6 of 16)
-
When the navigation glitched for the Lowrance, records were sent to the GPS file, but the times and fixes were bogus. Chuck Worley discovered the glitches were a result of a bad wire associated with the navigation cable. These bogus records start by recording a time of 000001 with the second record showing a time of 000006. Based on the navigation in the rest of the file which has fixes roughly every five seconds, I'm assuming that although the times themselves are bogus, the time interval in seconds is accurately represented. Based on this, I manually went through the ship's navigation segments and manually removed the records I don't need - keeping only those ship fixes that were closest in time to the fixes I believed I needed. Of course the times in the ship's navigation don't match exactly with the times I need from the Lowrance system as the ship's navigation records a fix every 3 or 4 seconds. But simply keeping the closest ship fix in time all fixes were within 1 second relative to the resistivity navigation fix I needed. The resulting files are *trim.txt (where the * refers to the initial gap files from the ship navigation).
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- l7f1_gap1.txt
- l7f1_gap2.txt
- l8f1_gap1.txt
- l8f1_gap2.txt
Data sources produced in this process:
- l7f1_gap1trim.txt
- l7f1_gap2trim.txt
- l8f1_gap1trim.txt
- l8f1_gap2trim.txt
- Date: 2006 (process 7 of 16)
-
I use an AWK script to reformat the "trimmed" ship's navigation and write the output in the $GPRMC, $SDDPT and $SDMTW strings that the resistivity system will need. The ship system doesn't have temperature, so I used a constant value of 24.3 based on the existing temperature information from the Lowrance system. The new files are *.gps (where * refers to the trim prefix file name)
AWK script awknewgps:
BEGIN {
FS=","
}
{
FS=","
alltime=$2
hr=substr($2,1,2)
min=substr($2,4,2)
sec=substr($2,7,2)
month=substr($1,1,2)
day=substr($1,4,2)
yr=substr($1,9,2)
depth=$5
declon=$4 * -1
londeg=int(declon)
lonmin=(declon-londeg)*60
declat=$3
latdeg=int(declat)
latmin=(declat-latdeg)*60 >printf("$GPRMC,%s%s%s,A,%02d%06.3f,N,%03d%06.3f,W,000.0,0,%s%s%s,0,W*73\n",hr,min,sec,latdeg,latmin,londeg,lonmin,day,month,yr)
printf("$SDDPT,%s,0.0*56\n",depth)
printf("$SDMTW,24.3,C*01\n") }
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- l7f1_gap1trim.txt
- l7f1_gap2trim.txt
- l8f1_gap1trim.txt
- l8f1_gap2trim.txt
Data sources produced in this process:
- l7f1_gap1trim.gps
- l7f1_gap2trim.gps
- l8f1_gap1trim.gps
- l8f1_gap2trim.gps
- Date: 2006 (process 8 of 16)
-
I then used VI text editor to insert these properly formatted files into the necessary sections of the resistivity navigation files that had "holidays". I also noticed that each navigation stop/start on the Lowrance system incremented the date stamp by a day. As a precaution, I copied l7f1_mod.gps to l7f1_mod2.gps before fixing this date error. Once I was confident I was fixing it correctly, in line 8 I didn't take the intermediate step.
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- l7f1_gap1trim.gps
- l7f1_gap2trim.gps
- l8f1_gap1trim.gps
- l8f1_gap2trim.gps
Data sources produced in this process:
- l7f1_mod2.gps
- l8f1_mod.gps
- Date: 2006 (process 9 of 16)
-
Two other lines had navigation gaps. These gaps were the actual absence of any information, so these lines had to be split to enable the resistivity software to process the data. Simply used Microsoft WordPad to delete the one portion of the original navigation and save the file under a new name.
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- L10F2_part1.gps
- L10F2_part2.gps
- L13F1_part1.gps
- L13F1_part2.gps
- Date: 2009 (process 10 of 16)
-
Used an AWK script to reformat the these correct GPS files to generate a single comma-delimited text file.
AWK script awkhold:
BEGIN {
FS = ","
}
{
FS = ","
ARGC = 2
depth = -9999
temp = -9999
if ($1=="$GPRMC")
{
utctime = $2
date = $10
latdeg = substr($4,1,2)
latmin = substr($4,3,6)
declat = latdeg + (latmin/60)
londeg = substr($6,1,3)
lonmin = substr($6,4,6)
declon = -1 * (londeg + (lonmin/60))
if (NR==1) {
holddepth = -9999
holdtemp = -9999
}
else {
printf("%9.6f, %9.6f, %s, %s, %5.1f, %5.1f, %s\n", holddeclon, >holddeclat, holdutctime, holddate, holddepth, holdtemp, ARGV[2])
}
holdutctime = >substr(utctime,1,2)":"substr(utctime,3,2)":"substr(utctime,5,2)
holddate = date
holddeclon = declon
holddeclat = declat
holddepth = -9999
holdtemp = -9999
}
if ($1=="$SDDPT")
{
depthreal = $2
holddepth = depthreal
}
if ($1=="$SDMTW")
{
tempreal = $2
holdtemp = tempreal
}
}
END {
printf("%9.6f, %9.6f, %s, %s, %5.1f, %5.1f, %s\n", holddeclon, holddeclat, >holdutctime, holddate, holddepth, holdtemp, ARGV[2])
}
The running of the script was initiated with a simple executable shell script "doawk":
files=`ls *.gps | cut -d. -f1`
for file in $files
do
awk -f awkhold $file.gps $file >> resnav_jd250.txt
done
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
- L7F1_mod2.gps
- L8F1_mod.gps
- F9L1.gps
- F10L1.gps
- F10L1.gps
- L10F2_part1.gps
- L10F2_part2.gps
- L11F1.gps
- L12F1.gps
- L13F1_part1.gps
- L13F1_part2.gps
- L14F1.gps
- L15F1.gps
- L16F1.gps
- L17F1.gps
- L18F1.gps
- L19F1.gps
Data sources produced in this process:
- Date: 2009 (process 11 of 16)
-
I then used VI to add the appropriate header line and the comma-delimited text file was imported to ArcMap 9.2: Tools - Add XY Data. The X field is longitude; Y field is latitude, and the Coordinate System was defined as Geographic, NAD83. Because of the format of the "gpstime" field, the default for ArcMap is to import this as a date/time field. Because I wanted this field to remain a text field, I edited the schema.ini file in the folder with the text file to define each attributes definition. I also made sure the DATE field imported as a text attribute to preserve the leading zero. I then used the data export (right-mouse click on the event theme, Data - Export Data) to save the event theme as a shapefile.
schema.ini:
[resnav_jd250.txt]
Format=CSVDelimited
ColNameHeader=True
Col1=longitude Double
Col2=latitude Double
Col3=gpstime Text Width 8
Col4=gpsdate Text Width 10
Col5=depth_m float
Col6=temp_c float
Col7=linename Text Width 11
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- Date: 2009 (process 12 of 16)
-
Using ArcMap 9.2 added the attributes "gps_src' and "bathy_src" so that I could differentiate the source of each navigation fix and bathymetry value. I selected the records in lines 7 and 8 that correspond to the times that I used the ship data and used the field calculator in the attribute table to specify these records as "ship gps" and "ship fathometer". All the remaining records were assigned "Lowrance gps" and "Lowrance fathometer".
Person who carried out this activity:
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
Woods Hole Coastal and Marine Science Center
Woods Hole,
MA
(508) 548-8700 x2251 (voice)
(508) 457-2310 (FAX)
vatnipp@usgs.gov
Data sources used in this process:
Data sources produced in this process:
- Date: 20-Oct-2016 (process 13 of 16)
-
Edits to the metadata were made to fix any errors that MP v 2.9.34 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). The source information was incomplete and had to be modified to meet the standard. The distribution format name was modified in an attempt to be more consistent with other metadata files of the same data format. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent.
Person who carried out this activity:
U.S. Geological Survey
Attn: VeeAnn A. Cross
Marine Geologist
384 Woods Hole Road
Woods Hole,
MA
508-548-8700 x2251 (voice)
508-457-2310 (FAX)
vatnipp@usgs.gov
- Date: 20-Jul-2018 (process 14 of 16)
-
USGS Thesaurus keywords added to the keyword section.
Person who carried out this activity:
U.S. Geological Survey
Attn: VeeAnn A. Cross
Marine Geologist
384 Woods Hole Road
Woods Hole,
MA
508-548-8700 x2251 (voice)
508-457-2310 (FAX)
vatnipp@usgs.gov
- Date: 18-Nov-2019 (process 15 of 16)
-
Crossref DOI link was added as the first link in the metadata.
Person who carried out this activity:
U.S. Geological Survey
Attn: VeeAnn A. Cross
Marine Geologist
384 Woods Hole Road
Woods Hole,
MA
508-548-8700 x2251 (voice)
508-457-2310 (FAX)
vatnipp@usgs.gov
- Date: 08-Sep-2020 (process 16 of 16)
-
Added keywords section with USGS persistent identifier as theme keyword.
Person who carried out this activity:
U.S. Geological Survey
Attn: VeeAnn A. Cross
Marine Geologist
384 Woods Hole Road
Woods Hole,
MA
508-548-8700 x2251 (voice)
508-457-2310 (FAX)
vatnipp@usgs.gov
