Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2003 Title: Geophysical Surveys of Bear Lake, Utah-Idaho, September 2002 - Bathymetric Grid Geospatial_Data_Presentation_Form: Raster 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 (chrip) 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followed an earlier subbottom acoustic-reflection survey (1997), using boomer and 3.5 kHz systems (S. M. Colman, unpublished data).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: The bathymetric contours will be used as a reference for depth information within Bear Lake, Utah-Idaho. No bathymetric surveys have been conducted in the Lake since the 1970's. This dataset represents the most up-to-date bathymetric information for the area. 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: bathymetry Theme_Keyword: swath bathymetry Theme_Keyword: interferometry 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: Bathymetry is not to be used for navigational purposes. 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; all data were acquired with an SEA 2000 Series Submetrix interferometric sonar. Logical_Consistency_Report: These data are were checked for consistency by plotting the point data with the contoured surface and eliminating suprious and anomolous soundings. Completeness_Report: These data are complete. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: All navigation data were acquired using the Wide Area Augmentation System (WAAS), a GPS-based navigation and landing system providing precision guidance to aircraft. Horizontal accuracy of the WAAS network is assumed to be accurate < 3 meters. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Vertical accuracy is dependant on the navigation system. All navigation data were acquired using the Wide Area Augmentation System (WAAS), a GPS-based navigation and landing system providing precision guidance to aircraft. The Wide Area Augmentation System (WAAS) is assumed to have a vertical accuracy of +/- 5 meters. All ship motion was recorded by a TSS DMS 2-05 Attitude Sensor. Lineage: Process_Step: Process_Description: Bathymetric data were corrected for variations in the speed of sound throughout the water column; sound velocity profiles were acquired at locations throughout the lake and throughout the survey period. Attitude sensor and compass information were incorporated into the header of the bathymetric data files using the SEA RTS2000 acquiistion and processing system. The resultant data files were imported into SEA GRID2000 program and gridded to a 10 meter grid cell size. Process_Date: 20020916 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 SEA GRID2000 file was then exported as x,y,z. The weighgrid command within the University of New Brunswick, Ocean Mapping Group, SwathEd software was used to interpolate the data to fill in between line data gaps. An interpolation of 300 meter radius was used. Process_Date: 20020916 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 grid file was then converted to an ASCII Raster file and imported to ESRI ArcView 3.2. Process_Date: 20020916 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: That Raster Grid was converted to a TIFF image using an ArcView extension 'image_convert_georef.ave' downloaded from the ESRI website (www.esri.com). The extension coverted the Grid to a TIFF image maintaining the grid legend. A TIFF world file was also generated. Process_Date: 20020916 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 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 12 Transverse_Mercator: Scale_Factor_at_Central_Meridian: .9996 Longitude_of_Central_Meridian: -111.000000 Latitude_of_Projection_Origin: +00.000000 False_Easting: 500000 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: Coordinate Pair Coordinate_Representation: Abscissa_Resolution: 5 Ordinate_Resolution: 5 Planar_Distance_Units: meters Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: Local Lake Level Datum Altitude_Resolution: 1 Altitude_Distance_Units: meters Altitude_Encoding_Method: implicit coordinate Depth_System_Definition: Depth_Datum_Name: Local Surface Depth_Resolution: 1 Depth_Distance_Units: meters Depth_Encoding_Method: Attribute Values 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: Bathymetric Grid - TIFF Image Format 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