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followed an earlier subbottom acoustic-reflection survey (1997), using boomer and 3.5 kHz systems (S. M. Colman, unpublished data).
Denny, Jane F. , 2002, Geophysical Surveys of Bear Lake, Utah-Idaho, September 2002 - Chirp Seismic Tracklines: ESRI ArcView shapefile version 3.2, U.S. Geological Survey, Woods Hole, MA.
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000089992. Longitudes are given to the nearest 0.000089992. Latitude and longitude values are specified in decimal degrees.
The horizontal datum used is WGS84.
The ellipsoid used is WGS84.
The semi-major axis of the ellipsoid used is 6378137.0000000.
The flattening of the ellipsoid used is 1/298.26.
ArcView 3.2
ESRI ArcView 3.2
ArcView 3.2
Line Number
Hotlink absolute directory path
Jane F. Denny
U.S. Geological Survey
Geologist
384 Woods Hole Road
Woods Hole, MA 02543
USA
508-457-2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
These data represent trackline navigation data seismic-reflection systems utilized during U.S. Geological Survey geophysical research cruises.
Person who carried out this activity:
Jane F. Denny
U.S. Geological Survey
Geologist
384 Woods Hole Road
Woods Hole, MA 02543
USA
508-457-2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
WAAS (Wide Area Augmentation System) Navigation was used to acquire navigation information. WAAS is considered to have a horizontal accuracy of < 3 meters. The chirp tow-vehicle was towed at the surface, next to the vessel. WAAS positioning was recorded in the SEGY header of the seismic data. Navigation of the seismic tow-vehicle is assumed to be +/- 3 meters.
Complete
These navigation data have been stripped from the header of seismic SEG-Y data. They have been quality checked by comparing these data to navigation data acquired during cruise operations.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- The U.S. Geological Survey must be referenced as the originator of the dataset in any future publications.
Jane F. Denny
U.S. Geological Survey
Geologist
384 Woods Hole Road
Woods Hole, MA 02543
USA
508-457-2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
This publication was 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 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 on this CD-ROM 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.
Jane F. Denny
U.S. Geological Survey
Geologist
384 Woods Hole Road
Woods Hole, MA 02543
USA
508-457-2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov