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ArcExplorer Project for the Crater Lake 2000 Multibeam Sonar Survey

The Crater Lake multibeam survey took place from July 28 to August 3, 2000 using a Kongsberg Simrad EM1002 Multibeam Sonar System. The system collects both bathymetry and co-registered, calibrated backscatter data. For more in-depth information about the survey and the EM1002 system, see the USGS Open-File Report 00-405.

This CD-ROM contains an ArcExplorer 2.0 project of the Crater Lake multibeam bathymetry and backscatter imagery. ArcExplorer is a freeware, GIS software package developed by ESRI. This project allows the user to overlay, zoom, pan, and query the Crater Lake multibeam and other data. Other spatial data in UTM coordinates can be added to this project, which can be used in research projects.

This ArcExplorer project will only run an a PC running Windows 98/2000/NT.

If the user already has ArcExplorer 2.0 installed on the computer just go to the clproj directory and open the ArcExplorer project file "craterlake.AEP".

If the user needs to install ArcExplorer 2.0, go to the software directory and copy the ae2setup.exe file to the desktop. Double click on the ae2setup.exe icon and follow the installation instructions. The software may also be downloaded directly from ESRI.

Contents of ArcExplorer project

CONTOUR - 50-meter depth contours of the lake floor from -50 to -550 m generated from the multibeam bathymetry data.

CLRSHADE.TIF - Colored shaded-relief TIFF image generated from the multibeam bathymetry data. The colors show relative depths: reds and oranges represent shallower depths and blues represent deeper depths. The colored shaded-relief bathymetry image (2-m resolution) is merged with a black and white shaded-relief image of the surrounding mountains separately generated from USGS 10-meter, 7.5 minute DEM`s.

BACKSTR.TIF - Gray-scale TIFF image generated from the multibeam backscatter data. The brighter tones indicate stronger acoustic returns off the lake floor (possibly hard surfaces such as rock) and the darker tones indicate weaker acoustic returns off the lake floor (possibly sediment). The brighter vertical lines in the center of the lake are data collection artifacts and are caused by an artificially high acoustic return near nadir (the area directly below the survey vessel).

Data Information

Projection: UTM
Datum: WGS84
Units: meters
Zunits: meters (bathymetry)
Spatial Resolution: 2 meters

Federal Geographic Data Committee (FGDC) Metadata:

Multibeam Data
Text Format
HTML Format
FAQ format

USGS Digital Elevation Models (DEMs) for Crater Lake (World Wide Web site)

March 4, 2009 (Mike Diggles)