• Introduction
• CD-ROM Directory Structure
• Getting Started
• System Requirements
• Disclaimer

CD-ROM Contents

Geophysical Surveys of Bear Lake, Utah-Idaho, September, 2002

USGS Open-File Report 03-150

Table of Contents:

• Introduction
• CD Directory Structure
• Getting Started
• System Requirements
• Disclaimer
  

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Introduction

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. 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.

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CD-ROM Contents

The contents of this CD-ROM are as follows:

Top level Directory:

• index.htm - This file is intended to be the starting point for CD-ROM access. It is written in the Hypertext Markup Language utilized by the World Wide Web (WWW) project and must be opened with a WWW browser. Once opened, the user may browse the CD-ROM's contents as they would browse pages from the WWW.
  
• readme.txt - ASCII text file containing a description of this CD-ROM. This file may be viewed or printed with any system program capable of opening an ASCII text file.
  

• arcview - this directory contains the ESRI ArcView 3.2 project file, 03-150.apr and the following directories:
  
  
  • bathy - contains a TIFF image of the bathymetric data and corresponding world file
  
  
  
  • dem - contains the 10 meter Digital Elevation Model stored in an ESRI GRID format and as a TIFF file with associated ESRI world file
  
  
  
  • images -
  • grab - contains the JPEG images of the grab sample data
  
  
  • seis- contains the JPEG images of the seismic data
  
  
  • svp - contains the JPEG images of the sound velocity profiles
  
  
  • metadata - contains the metadata for all the files utilized within the project file
  
  
  
  • mosaic- contains the following sidescan-sonar mosaic files:
    bear.tif/bear.tfw - full resolution TIFF image (1 meter/pixel)
    bear.sid/bear.sdw - MrSID compressed image file
  
  
  
  • shape
  - contains all of the shapefiles found within the project file, subdivided as follows:
  • bathy
  
  
  • samples
  
  
  • tracks
  .

• html - contains all HTML pages accessed within this CD-ROM.
  
  • images - contains the image files utilized within HTML pages
  
  
  • PDF - contains PDF version of Figures

• ivs- contains the 3D scene and object files viewable with iView3D. See Getting Started.

• nav - contains the seismic shot, sonar, and bathymetric navigation file in ASCII format

• posters - contains two map sheets: Bathymetry (sheet 1) and Sidescan-sonar (sheet 2) in PDF format. These files can be opened in Adobe Acrobat or Adobe Illustrator and printed.

• svp - contains a Microsoft Excel file listing all sound velocity profiles
  

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Figure 10. Three-dimensional view of sidescan-sonar and bathymetry data collected within Bear Lake, Utah-Idaho.

Download Information:

• Go to the IVS website
• Go to Products
• Click on iView3D
This will take the User to the iView3D Home Page. The User will find a program description and detailed downloading instructions. It is highly recommended that the User download iView3D in order to view the sidescan-sonar and bathymetric data in three dimensions and 'fly-through' the study area. The HELP within iView3D gives detailed operating instructions.

Fledermaus Object and Scene Files:


The following files can be viewed within iView3D. See iView3D HELP for detailed instructions.


• 3d.scene - bathymetry and sidescan-sonar
• sidescan.sd - sidescan-sonar image
• bathy.sd - bathymetric data

To Load of03-150.apr:

• of03-150.apr contains a startup script, Drive Selection. This script will run upon startup and will prompt the user for the directory path to the images directory. This information is needed in order to establish the 'hotlinks' found within the project file. This script can also be accessed within the project file. Click on the 'fireworks' button, found on the menu/button bar within of03-150, to rerun the Drive Selection script. This button enables the user to modify the directory path to the images directory at any time.
  

Extensions:

• Vector and point data are 'hotlinked' to JPEG image files within of03-150.apr. The JPEG (JFIF) Image Support extension must be loaded in order to view these image files. This extension is loaded by default within the project file.
  
• This project file utilizes RASTER image files (TIFF) compressed with LizardTech (www.lizardtech.com) MrSID Geospatial Encoder 1.3.1 image compression utility. In order to load and view these files the MrSID Image Support extension must be loaded. This extension will be loaded by default within of03-150.apr.
  

Views:

The Bear Lake View within of03-150.apr is projected in the following coordinate system: UTM, WGS84 datum, Zone 12, meters. All raster images and grids are also projected in UTM. All point and vector data are stored in decimal degrees.

NOTE: Hotlinks - The seismic trackline data, sample and sound velocity profile locations are 'hotlinked' to JPEG images of the seismic data, photographs of the sediment samples, and images of the sound velocity profiles, respectively. To view the JPEG images, activate either the trackline, sample or sound velocity profile shapefile by clicking the shapefile name within the View Table of Contents. Click on the lightening bolt within the tool menu bar, then click on an individual trackline or sample location within the active theme. A JPEG image of the seismic data collected along the chosen line will appear. The JPEG images are stored in a view window; the user can zoom, pan, and alter the window size. Click on the X in the upper right corner to close the window.

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System Requirements

This CD-ROM can be successfully accessed on systems utilizing the following operating systems: Microsoft Windows, Macintosh and UNIX. However, the ESRI ArcView project file, of03-152.apr, and the IVS free viewer, iView3D, will only run on Microsoft Windows systems.

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Disclaimer

This Compact Disc-Read Only Memory (CD-ROM) 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 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 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.

To view files in PDF format, download free copy of Adobe Acrobat Reader www.adobe.com/products/acrobat/alternate.html.