John F. Bratton
VeeAnn A. Cross
2005
Processed Continuous Resistivity Profile Collected in the Neuse River, April 19, 2004
Open-File Report
2005-1306
Woods Hole Coastal and Marine Science Center, Woods Hole, MA
U.S. Geological Survey, Coastal and Marine Geology Program
https://doi.org/10.3133/ofr20051306
http://pubs.usgs.gov/of/2005/1306/data/2004/proc_resis/apr19_proc.zip
VeeAnn A. Cross
John F. Bratton
Emile Bergeron
Jeff K. Meunier
John Crusius
Dirk Koopmans
2005
Continuous Resistivity Profiling Data from the Upper Neuse River Estuary, North Carolina, 2004-2005
Open-File Report
2005-1306
Reston, VA
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1306/
The Neuse River Estuary in North Carolina is a broad, V-shaped water body located on the southwestern end of Pamlico Sound. This estuary suffers from severe eutrophication for which several water quality models have recently been developed to aid in the management of nutrient loading to the estuary. In an effort to help constrain model estimates of the fraction of nutrients delivered by direct ground-water discharge, continuous resistivity profile (CRP) measurements were made during the spring of 2004 and 2005. CRP is used to measure electrical resistivity of sediments, a property that is sensitive to difference in salinity of submarine ground water. The 2004 and 2005 surveys used floating resistivity streamers of 100 m and 50 m respectively. The depth penetration of the streamers is approximately 20% of the streamer length which translates to approximately 20-25 m with the 100 m streamer and 12-14 m with the 50 m streamer. These data were processed using AGI's EarthImager 2D software. CRP data enables the mapping of the extent and depth of the fresher ground water within the estuary.
To provide resistivity data as collected by the AGI SuperSting system and processed with EarthImager software.
20040419
ground condition
None planned
-76.729717
-76.713317
34.972333
34.966467
USGS Metadata Identifier
USGS:79c17bb6-9067-4890-a11f-89154f443c93
None
CMGP
coastal
Coastal and Marine Geology Program
Continuous Resistivity Profiling
CRP
ground-water
marine resistivity
submarine ground-water
U.S. Geological Survey
USGS
Woods Hole Science Center
Open-File Report
OF 2005-1306
USGS Thesaurus
continuous resistivity profiling
image collections
None
Neuse River
North America
North Carolina
Pamlico Sound
United States
none.
The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.
John F. Bratton
U.S. Geological Survey
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2254
(508) 457-2310
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535
Information unavailable from original metadata.
Information unavailable from original metadata.
U.S. Geological Survey
Unpublished material
Raw CRP Data
hard disk
20040419
ground condition
raw crp data
These data were acquired with an AGI SuperSting Marine system that is described at the website: www.agiusa.com/marinesystem.shtml. The particular system used for this acquisition was an 11 stainless steel electrode array with electrodes spaced 10 meters apart. A dipole-dipole configuration was used for the data collection in which two fixed current electrodes are assigned with the measurement of voltage potentials between electrode pairs in the remaining electrodes. Each line of data acquisition records several files. The two files necessary for processing are the *.stg and *.gps file. The STG file contains the resistivity data, while the GPS file contains the navigation information.
The data were transferred from the logging computer via AGISSAdmin software. The data file available for this day is N2.*.
Unknown
A section of the STG file was removed due to bad time stamps (between records 1913 and 1920). $GPRMC lines within the GPS file that had bad time stamps or were otherwise corrupt were also deleted.
N2.stg and N2.gps
Unknown
N2_mod.stg and N2_mod.gps
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
(508) 548-8700 x2251
(508) 457-2310
vatnipp@usgs.gov
The data were merged with navigation and linearized using AGI's Marine Log Manager software.
Unknown
The file was then exported to a new STG file, and accompanying DEP file. The DEP file contains the distance along line and bathymetry values.
N2_mod.stg
Unknown
N2proc.stg, N2proc.dep
The DEP file was checked for anomalous bathymetry values and those lines in the file were deleted.
N2proc.dep
Unknown
N2proc_mod.dep
EarthImager software does not require that a default resistivity value for the water column be supplied in the DEP file. If one is not supplied, then it calculates a value based on the first electrode pair. For this reason, the data were processed without a value supplied (in the folder def_wres), and with a value supplied (in the folder wres). The average water resistivity value was calculated based on YSI temperature and conductivity data readings during the survey.
N2proc_mod.dep
Unknown
N2proc_wres.dep
EarthImager version 1.9.0 was used to process the data files. The *.ini file accompanying the results contains the parameters used during the processing. These parameters include:
minimum voltage: 0.02
minimum abs(V/I): 2E-5
max repeat error: 3%
min apparent res: 0.03
max apparent res: 1000
max reciprocal error: 5%
remove spikes
smooth model inversion
finite difference method
Cholesky decomposition
Dirichlet boundary condition
thickness incremental factor: 1.1
depth factor: 1.1
number of iterations: 8
stop criteria: max RMS 3%, error reduction 5%, L2Norm
CRP processing using a 65% overlap
Unknown
The results of the processing are a JPEG image of the resistivity profile, and an XYZ file containing the distance along, depth, apparent resistivity (ohm-m). The first pass at processing (Trial1) used the default water resistivity value, while the second pass (Trial2) used the average water resistivity value in the DEP file. The JPEG file produced uses a color scale that is based on the data from this particular file.
**Caution: The XYZ output filename does not contain the trial number, so the processing technique is a function of the folder it resides in.
Unknown
N2proc_AllInvRes.xyz, N2proc_trial1_InvResShort.jpg, N2proc_trial2_InvResShort.jpg
The XYZ output file was then loaded into Matlab, along with the depth information, to create a new JPEG image with the same color scale for all the data files. In this manner, the JPEG images can be compared directly. Care was taken to try to get the vertical and horizontal scales uniform as well, although this was not always possible due to Matlab limitations. These images reside in the Matlab images folder. Part of the filename (defwres vs. wres), as well as information within the image indicates if the default water resistivity (defwres) data file was used or an average water resistivity (wres) value.
N2proc_AllInvRes.xyz
Unknown
N2proc_defwres.jpg, N2proc_wres.jpg
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. None of the process steps had process dates, so those were set to unknown. The distributor information needed to be added, along with the distribution format and network resource. 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.
20161028
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543
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
Crossref DOI link was added as the first link in the metadata.
20191118
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
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Downloadable Data
These data were prepared by an agency of the United States Government. Neither the United States government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Although all data published in this report have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.
TEXT
http://pubs.usgs.gov/of/2005/1306/data/2004/proc_resis/apr19_proc.zip
JPEG
http://pubs.usgs.gov/of/2005/1306/data/2004/proc_resis/apr19_proc.zip
None
20240318
VeeAnn A. Cross
U.S. Geological Survey
Marine Geologist
mailing and physical address
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