John F. Bratton
VeeAnn A. Cross
2014
Unique shot point navigation for chirp seismic data collected in Indian River Bay, Delaware, April 13, 2010, on U.S. Geological Survey Field Activity 2010-006-FA (IR_SEISNAV.SHP, Geographic, WGS 84)
1
vector digital data
Open-File Report
2011-1039
Woods Hole Coastal and Marine Science Center, Woods Hole, MA
U.S. Geological Survey, Coastal and Marine Geology Program
https://doi.org/10.3133/ofr20111039
https://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html
https://pubs.usgs.gov/of/2011/1039/data/navigation/seismics/ir_seisnav.zip
V.A. Cross
J.F. Bratton
H.A. Michael
K.D. Kroeger
A. Green
E. Bergeron
2014
Continuous Resistivity Profiling and Seismic-Reflection Data Collected in April 2010 from Indian River Bay, Delaware
1
Open-File Report
2011-1039
Reston, VA
U.S. Geological Survey
https://pubs.usgs.gov/of/2011/1039/
https://doi.org/10.3133/ofr20111039
A geophysical survey to delineate the fresh-saline groundwater interface and associated sub-bottom sedimentary structures beneath Indian River Bay, Delaware, was carried out in April 2010. This included surveying at higher spatial resolution in the vicinity of a study site at Holts Landing, where intensive onshore and offshore studies were subsequently completed. The total length of continuous resistivity profiling (CRP) survey lines was 145 kilometers (km), with 36 km of chirp seismic lines surveyed around the perimeter of the bay. Medium-resolution CRP surveying was performed using a 50-meter streamer in a bay-wide grid. Results of the surveying and data inversion showed the presence of many buried paleochannels beneath Indian River Bay that generally extended perpendicular from the shoreline in areas of modern tributaries, tidal creeks, and marshes. An especially wide and deep paleochannel system was imaged in the southeastern part of the bay near White Creek. Many paleochannels also had high-resistivity anomalies corresponding to low-salinity groundwater plumes associated with them, likely due to the presence of fine-grained estuarine mud and peats in the channel fills that act as submarine confining units. Where present, these units allow plumes of low-salinity groundwater that was recharged onshore to move beyond the shoreline, creating a complex fresh-saline groundwater interface in the subsurface. The properties of this interface are important considerations in construction of accurate coastal groundwater flow models. These models are required to help predict how nutrient-rich groundwater, recharged in agricultural watersheds such as this one, makes its way into coastal bays and impacts surface water quality and estuarine ecosystems. For more information on the survey conducted for this project, see https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-006-FA.
The purpose of the data layer is to provide all of the unique shot point navigation associated with the seismic-reflection profiles collected on U.S. Geological Survey Field Activity Number 2010-006-FA. This information can help correlate the seismic-reflection profiles with other features and data in the GIS. This clean, unique shot point navigation is also used as the navigation when loading the seismic data into a digital interpretation software package.
20100413
ground condition
None planned
-75.202086
-75.062936
38.618986
38.569244
USGS Metadata Identifier
USGS:6b1e6250-13af-46b2-80a4-4fc4885a918c
None
U.S. Geological Survey
USGS
Coastal and Marine Geology Program
CMGP
Woods Hole Coastal and Marine Science Center
WHCMSC
Field Activity Number 2010-006-FA
Info Bank ID K-6-10-DL
navigation
shot point navigation
seismic navigation
R/V Knob
Lowrance GPS
point shapefile
EdgeTech 424
chirp seismics
Open-file Report 2011-1039
ISO 19115 Topic Category
location
oceans
USGS Thesaurus
navigational data
marine geophysics
geospatial datasets
None
North America
North Atlantic Ocean
United States
Delaware
Indian River Bay
Indian River Inlet
Holts Landing
Piney Neck
Sussex County
Rosedale Beach
None.
The public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
Woods Hole Coastal and Marine Science Center
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2251
(508) 457-2310
vatnipp@usgs.gov
https://pubs.usgs.gov/of/2011/1039/data/navigation/seismics/ir_seisnav_th.gif
Thumbnail GIF image showing the location of all seismic shot points collected in Indian River Bay. The coastline is included for spatial reference.
GIF
Microsoft Windows Vista Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 9.3.1.4095
Michael W. Norris
Alan K. Faichney
2002
SEG Y rev1 Data Exchange Format
document
Tulsa, OK
Society of Exploration Geophysicists
http://www.seg.org/documents/10161/77915/seg_y_rev1.pdf
John W. Stockwell Jr.
Jack K. Cohen
2008
The New SU User's Manual (version 4.0)
document
Golden, CO
Center for Wave Phenomena - Colorado School of Mines
http://www.cwp.mines.edu/cwpcodes/
These points were visually checked to make sure they were viable fixes. All days were handled the same way.
This shapefile represents all the unique shot point navigation collected during USGS Field Activity Number 2010-006-FA.
The navigation system used was a Lowrance 480M with an LGC-2000 Global Positioning System (GPS) antenna. The antenna was located above the seismic towfish tow point. The system towfish was attached by a short line to a cleat on a 2 x 6 board that was clamped across the bow of the boat. The towfish was on the starboard side of the boat, approximately 0.5 meters below the water surface. GPS data are assumed to be accurate within 10 meters on this survey.
Although bathymetry was not recorded directly with this system, bathymetry can be derived by tracing the seafloor reflector in the seismic-reflection profiles. The seismic towfish was attached to a cleat by a short line on the starboard side of the boat. The transducer draft was approximately 0.5 m below the water surface. The draft offset was not included in the data acquisition.
The seismic acquisition system used on this cruise was an EdgeTech 424 Chirp sub-bottom system with a 4 to 24 kHz pulse bandwidth and a 2 ms pulse. The system towfish was attached by a short line to a cleat on a 2 x 6 board that was clamped across the bow of the boat. The towfish was on the starboard side of the boat, approximately 0.5 meters below the water surface. The acquisition software used to record the data was Discover 3100 version 7.01. The data were recorded in the SEG-Y data format IBM floating point with navigation supplied by the Lowrance GPS system. The navigation was recorded in the header of the seismic data in an arc second format. The record length is 133 ms, with a sample interval of 23 micro-seconds and 5788 samples per trace. The fire-rate was between 4 and 6 shots per second. The GPS antenna was located above the tow position of the seismic transducer.
2010
SeismicUnix version 4.0 was run on a Linux system to extract the navigation from the header of the seismic SEG-Y files and create SU formatted seismic files. The navigation goes into an ASCII file with the extension txt and the seismic data in the SeismicUnix format goes into a file with the extension su. The script used to accomplish this was read_ir:
># read SEG-Y standard file and convert to SU native format
> echo " "
> echo "Read SEG-Y file and output SU native format..."
> echo " "
># Set endian=0 for Intel or DEC or endian=1 for Sun, SGI, MAC...
>segyread tape=$1.sgy verbose=1 vblock=1000 conv=1 endian=0 | \
> segyclean > $1.su
># extract SEG-Y trace header values (ffid, source x, source y, year,
># julian day, hour, minute, second, source depth, source elevation)
> echo " "
> echo "Extracting SEG-Y trace header words... (ffid, source X, source Y, year, julian day, hour, minute, seconds)"
> echo " "
>
> echo " "
> echo "Writing shot navigation files to nav directory..."
> echo " "
>
> sugethw key=tracl,sx,sy,year,day,hour,minute,sec output=ascii < $1.su | \
> grep tracl | sed 's/=/ /g' | sed 's/ //g' | \
> awk '{FS=" "} {OFS=" "} {printf "%6s%7s\t%5s\t%6s\t%9.6f\t%9.6f\t%4s\t%3s:%02d:%02d:%02d\n", \
> $4,$6,line,$2,$4/360000,$6/360000,$8,$10,$12,$14,$16} ' line=$1 - > ../nav/$1.temp.txt
>
> sort -b -g -um -k 1,2 ../nav/$1.temp.txt | cut -f2-7 > ../nav/$1.txt rm ../nav/$1.temp.txt
This process step and all subsequent process steps were performed by the same person: VeeAnn A. Cross.
*.sgy
201005
*.su
*.txt
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
Woods Hole Coastal and Marine Science Center
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2251
(508) 457-2310
vatnipp@usgs.gov
The individual text files for the seismic navigation were combined into a single text file using the Unix command "cat". This file was edited with VI and all the tabs were replaced with commas, and a header line was added.
*.txt
201005
seisnav.csv
Used ArcMap 9.2 - Tools -Add XY Data to load the text file as an event theme - defined the projection as Geographic, WGS84. Then right mouse click on the event theme - Data - Export Data and output all the records to ir_seisnav.shp.
seisnav.csv
201005
ir_seisnav.shp
Edits to the metadata were made to fix any errors that MP v 2.9.36 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.). Attempted to modify http to https where appropriate. Moved the minimal source information provided to make it the first process step. 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.
20171002
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
USGS Thesaurus keywords added to the keyword section.
20180720
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Added keywords section with USGS persistent identifier as theme keyword.
20200908
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Vector
Entity point
14416
0.000001
0.000001
Decimal degrees
D_WGS_1984
WGS_1984
6378137.000000
298.257224
ir_seisnav
ESRI point shapefile
ESRI
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
ESRI
Coordinates defining the features.
linename
The unique identifier for each line of data acquistion. This is the prefix of the SEG-Y filename.
U.S. Geological Survey
Character set.
shot
The seismic shot number associated with the navigation fix.
Software generated.
1
8966
shot
longitude
Longitude coordinate of the point in decimal degrees, WGS84.
U.S. Geological Survey
-75.202086
-75.062936
decimal degrees
latitude
Latitude coordinate of the point in decimal degrees, WGS84.
U.S. Geological Survey
38.569244
38.618986
decimal degrees
year
Year of data acquisition.
U.S. Geological Survey
2010
2010
year
jdtime
Julian day and time of the seismic shot in the format JJJ:HH:MM:SS. The Julian day number is the integer number representing the interval of time in days since January 1 of the year. The time is in UTC time which is +4 hours from local time during the survey.
U.S. Geological Survey
Character set.
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
Woods Hole Coastal and Marine Science Center
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2251
(508) 457-2310
vatnipp@usgs.gov
Downloadable Data
Neither the U.S. government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Shapefile
ArcGIS 9.2
Esri shapefile
This WinZip (v. 14) file contains the point shapefile, CSV file used to create the shapefile, as well as the associated metadata files.
0.6
https://pubs.usgs.gov/of/2011/1039/data/navigation/seismics/ir_seisnav.zip
https://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html
https://doi.org/10.3133/ofr20111039
CSV
information unavailable from original metadata
Comma separated values.
This WinZip (v. 14) file contains the point shapefile, CSV file used to create the shapefile, as well as the associated metadata files.
0.6
https://pubs.usgs.gov/of/2011/1039/data/navigation/seismics/ir_seisnav.zip
https://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html
https://doi.org/10.3133/ofr20111039
None.
This zip file contains data available in Esri point shapefile format. The user must have software capable of uncompressing the zip file and reading/displaying the shapefile.
20240318
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
Woods Hole Coastal and Marine Science Center
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2251
(508) 457-2310
whsc_data_contact@usgs.gov
The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240318)
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time