Geophysical Surveys of Bear Lake, Utah-Idaho, September, 2002 - Sidescan-sonar Mosaic
Geospatial_Data_Presentation_Form: raster data
Description:
Abstract:
Bear Lake is a tectonic lake that has existed for at
least several hundred thousand years. The lake basin
is a relatively simple half graben, a spoon-shaped depression
tilted toward the main fault on the east side of the lake. The U.S.
Geological Survey, in cooperation with researchers from several
universities, has been studying the sediments of Bear Lake since
1996. The general purpose of this effort is to reconstruct past
limnological conditions and regional climate on a range of timescales,
from hundreds of years to hundreds of thousands of years. This research
relates to a variety of human concerns, including water usage in
the Bear River basin. Past work has included several coring operations,
a seismic-reflection survey, sediment-trap deployments, a barge-mounted
drilling operation with the GLAD800 drill rig, and a variety of
other studies.
The objectives of the September, 2002 operations, preliminarily
reported here, were (1) to compile a detailed bathymetric map of
the lake using swath-mapping techniques, in order to provide baseline
data for a variety of applications and studies, and (2) to complete
a sidescan-sonar survey of the lake, providing a nearly complete
acoustic image of the lake floor. Limited amounts of subbottom acoustic-reflection
data (CHIRP) were also collected, along with samples of lake-floor
sediments representative of different kinds of backscatter patterns.
These surveys followed an earlier subbottom acoustic-reflection
survey (1997), using boomer and 3.5 kHz systems (S. M. Colman, unpublished
data).
Purpose:
These data represent the first sidescan-sonar survey of Bear Lake, Utah-Idaho.
This survey covered 100 percent of the lake floor below 5 meter water depth.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20020904
Ending_Date: 20020916
Currentness_Reference: Publication Date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -111.5
East_Bounding_Coordinate: -111.17
North_Bounding_Coordinate: 42.2
South_Bounding_Coordinate: 41.08
Keywords:
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: sonar
Theme_Keyword: Sidescan-sonar
Theme_Keyword: backscatter
Theme_Keyword: geophysics
Theme_Keyword: U.S. Geological Survey
Theme_Keyword: USGS
Theme_Keyword: Coastal and Marine Geology Program
Theme_Keyword: CMGP
Theme_Keyword: Woods Hole Field Center
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Bear Lake
Place_Keyword: Utah
Place_Keyword: Idaho
Place_Keyword: Western Lakes
Place_Keyword: North America
Place_Keyword: United States
Access_Constraints: None.
Use_Constraints: The USGS asks to be referenced in any use of these data.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane F. Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: USA
Contact_Voice_Telephone: 508-457-2311
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report: These data are internally consistent and accurate.
Logical_Consistency_Report:
These data are logically consistent; they were acquired
with an Edgetech DF-1000 sidescan-sonar system, and
processed following an identical procedure.
Completeness_Report: These data are complete.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
WAAS is assumed to be accurate within 1-2 meters.
Standard GPS is assumed accurate within 5-10 meters.
All data were recorded using the WAAS (Wide Area Augmentation System)
navigation. All WAAS data are referenced to WGS84 datum. Slant-range
distance was assumed to be negligable; the tow-fish was flown at a
static height adjacent to the boat.
Lineage:
Process_Step:
Process_Description:
The sidescan-sonar data were acquired with a 100 kHz Edgetech sidescan-sonar system.
All sidescan-sonar data were logged digitally at a sample
rate resulting in a 0.18-m pixel size in the across-track
direction and approximately 0.14-m in the along-track
direction following the methodology outlined in Danforth
and others (1991). A median filtering routine (Malinverno
and others, 1990) was applied to the sidescan-sonar data
to remove speckle noise, resulting in a 0.73-m pixel size.
The data for each survey were further processed and digitally mosaicked
using PCI Geomatica Software and procedures described in Danforth and others (1991),
Danforth (1997), and Paskevich (1992) resulting in an
enhanced, geographically correct, sidescan-sonar mosaic
with 1 meter/pixel resolution. The composite mosaic was
exported as a TIFF image, with an associated ESRI world file.
Source_Used_Citation_Abbreviation:
Danforth, W.W., 1997, Xsonar/ShowImage: A complete system for rapid sidescan-sonar processing and display: U.S. Geological Survey
Open File Report 97-686, 77 p.
Source_Used_Citation_Abbreviation:
Danforth, W.W., O'Brien, T.F., and Schwab, W.C., 1991, USGS Image processing system: near real-time mosaicking ofhigh-resolution sidescan-sonar data Sea Technology, Vol 1, p.54-59.
Source_Used_Citation_Abbreviation:
Malinverno, A., Edwards, M, and Ryan, W.B.F, 1990, Processing of SeaMARC swath sonar data: IEEE, Journal of Coean Enginneering, v.15, p. 14-23.
Source_Used_Citation_Abbreviation:
Paskevich, V., 1992, Digital mapping of sidescan-sonar data with the Woods Hole Image Processing System software: U.S. Geological Survey Open-File Report 92-536, 87.p
Process_Date: 20030916
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane F. Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: USA
Contact_Voice_Telephone: 508-457-2311
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Process_Step:
Process_Description:
The TIFF image (sonar.tif) was compressed using LizardTech, MrSID
GeoSpatial Encoder 1.3.1. This software compresses the image at a
specified ratio; 20:1 by default. An associated .sdw (ESRI world file) file
is written with the compressed .sid file. In order to view these data within ArcView, the MrSID
Image Support extension must be loaded. Once, the extension is loaded,
the .sid image file can be loaded into ArcView as an Image.
Entity_Type_Definition: Sidescan-sonar image stored in TIFF format
Entity_Type_Definition_Source: ESRI
Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane F. Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: USA
Contact_Voice_Telephone: 508-457-2311
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Resource_Description: bear.sid
Distribution_Liability:
Altough this data set and its lineage have been used by
the USGS, no warranty, expressed or implied, is made by
the USGS as to the accuracy of the data and/or it's related
materials. The act of distribution shall not constitute any
such warranty, and no resposibility is assumed by the
USGS in the use of these data or related items. Users must
assume resposibility for the proper use of this data. This
data should not be used at resolutions for which
it is not intended. This data has no been reviewed for
conformity with U.S. Geological Survey editorial standards,
or the North American Strigraphic code. Any use of trade,
product, or firm names is for descriptive purposes only
and does not imply endorsement by the US Government.
Metadata_Reference_Information:
Metadata_Date: 20020119
Metadata_Review_Date: 2002
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jane F. Denny
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: USA
Contact_Voice_Telephone: 508-457-2311
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: jdenny@usgs.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Access_Constraints: None
Metadata_Use_Constraints: None
Generated by mp version 2.7.17 on Wed Jul 02 14:24:35 2003