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Los Angeles and San Diego Margin High-Resolution Multibeam Bathymetry and Backscatter Data

Open-File Report 2004-1221
HOME
DATA
ARCINFO GRID format
XYZ format
LOCATION MAPS
Los Angeles (112 kb)
San Diego (101 kb)
METADATA

ESRI ArcInfo GRID Format Data

This Open-File Report contains the multibeam bathymetry and acoustic backscatter data that the USGS, Western Region, Coastal and Marine Geology Team has processed into GIS ready formats as of April 2004.

The data are available in ESRI ArcInfo GRID (UTM, zone 11 projection) and XYZ (geographic coordinates) formats.

 

ESRI ArcInfo GRID Download Instructions

  1. Click on the links below to download the files.
  2. Uncompress and unbundle the file. ESRI GRIDs are directories of files. The directories have been bundled into a single file and then compressed for downloading.

      Windows - Double click on the file (i.e. dumebat.tgz). Winzip will uncompress the file resulting in a new bundled file (i.e. dumebat.tar). Double click on the new file and Winzip will unbundle the file into a new folder (i.e. dumebat). The ESRI GRID (i.e. dumebatg) is contained within the folder.

      UNIX - Uncompress using "gunzip" then unbundle using "tar -xf".

These datasets in their present form were not originally intended for publication. The bathymetry and backscatter have data-collection and processing artifacts. These data are being made public to fulfill a Freedom of Information Act request. Care must be taken not to confuse artifacts with real seafloor morphology and acoustic backscatter.

Downloading files can sometimes be problematic. Different web browsers and operating systems act differently. The instructions above may vary from system to system or may not work at all. One possible problem when downloading a file using Netscape is the *.tgz extension automatically changes to *.tar and the file does not uncompress correctly. If this is the case, change the *.tar back to *.tgz and uncompress as normal.

 
Los Angeles Margin Bathymetry (see Location Map)
GRID File File Information
DUMEBAT.TGZ value = depth: min = -298.78m,
max = -14.51m, 4-m spatial resolution,
1Mb compressed, 6Mb uncompressed
DELREYBAT.TGZ value = depth: min = -32.24m,
max = -17.88m, 4-m spatial resolution,
2Mb compressed, 22Mb uncompressed
REDONBAT.TGZ value = depth: min = -382.79m,
max = -11.07m, 4-m spatial resolution,
9Mb compressed, 23Mb uncompressed
PVBAT.TGZ value = depth: min = -486.53m,
max = -8-84m, 4-m spatial resolution,
10Mb compressed, 53Mb uncompressed
NTHSLFBAT.TGZ value = depth: min = -680.34m,
max = -14.71m, 8-m spatial resolution,
9Mb compressed, 17Mb uncompressed
MIDSLFBAT.TGZ value = depth: min = -444.68m,
max = -11.07m, 8-m spatial resolution,
10Mb compressed, 36Mb uncompressed
OUTSLFBAT.TGZ value = depth: min = -567.66m,
max = -28.49m, 8-m spatial resolution,
12Mb compressed, 48Mb uncompressed
GABBAT.TGZ value = depth: min = -82.36m,
max = -20.14m, 4-m spatial resolution,
15Mb compressed, 36Mb uncompressed
HUNTBAT.TGZ value = depth: min = -101.86m,
max = -2.82m, 4-m spatial resolution,
15Mb compressed, 38Mb uncompressed
NPHBAT.TGZ value = depth: min = -203.47m,
max = -1.94m, 4-m spatial resolution,
6Mb compressed, 32Mb uncompressed
PVEBAT.TGZ value = depth: min = -59.21m,
max = -2.98m, 4-m spatial resolution,
4Mb compressed, 23Mb uncompressed
SPBBAT.TGZ value = depth: min = -43.87m,
max = -5.77m, 8-m spatial resolution,
16Mb compressed, 36Mb uncompressed

 
San Diego Margin Bathymetry (see Location Map)
SDMARBAT.TGZ value = depth: min = -1229.03m,
max = -17.759m, 8-m spatial resolution,
32Mb compressed, 78Mb uncompressed
SDAREA0BAT.TGZ value = depth: min = -96.78m,
7Mb compressed, 11Mb uncompressed
SDAREA2BAT.TGZ value = depth: min = -86.29m,
max = -17.47m, 4-m spatial resolution,
9Mb compressed, 31Mb uncompressed

 
Los Angeles Margin Backscatter (see Location Map)
GRID File File Information
DUMEMOS.TGZ value = digital number: min = 47.00,
max = 250.00, 2-m spatial resolution,
5Mb compressed, 25Mb uncompressed
DELREYMOS.TGZ value = digital number: min =54.00,
max = 230.12, 2-m spatial resolution,
6Mb compressed, 90Mb uncompressed
REDONMOS.TGZ value = digital number: min = 25.39,
max = 250.28, 2-m spatial resolution,
30Mb compressed, 93Mb uncompressed
PVMOS.TGZ value = digital number: min = 4.00,
max = 252.00, 2-m spatial resolution,
7Mb compressed, 13Mb uncompressed
NTHSLFMOS.TGZ value = digital number: min = 25.54,
max = 253.24, 4-m spatial resolution,
31Mb compressed, 70Mb uncompressed
MIDSLFMOS.TGZ value = digital number: min = 0.00,
max = 249.00, 4-m spatial resolution,
37Mb compressed, 146Mb uncompressed
OUTSLFMOS.TGZ value = digital number: min = 0.54,
max = 249.00, 4-m spatial resolution,
44Mb compressed, 193Mb uncompressed
GABMOS.TGZ value = digital number: min = 63.28,
max = 225.38, 4-m spatial resolution,
15Mb compressed, 36Mb uncompressed
HUNTMOS.TGZ value = digital number: min = 3.0,
max = 225.60, 4-m spatial resolution,
13Mb compressed, 38Mb uncompressed
NPHMOS.TGZ value = digital number: min = 115.00,
max = 234.05, 4-m spatial resolution,
6Mb compressed, 29Mb uncompressed
PVEMOS.TGZ value = digital number: min = 66.00,
max = 229.96, 4-m spatial resolution,
4Mb compressed, 21Mb uncompressed
SPBMOS.TGZ value = digital number: min = 93.24,
max = 225.22, 4-m spatial resolution,
14Mb compressed, 34Mb uncompressed

* NOTE: Acoustic backscatter strength has been converted from decibels (dB) to a non-dimensional digital number (DN) using the conversion,

Absolute Value(2DN/dB)

Projection Information
UTM
Zone 11
Units: Meters
Zunits: NO [backscatter]; Meters [bathymetry]
Datum: WGS84

This data is not to be used for navigation

FGDC Compliant Metadata for ESRI ArcInfo GRID format

 

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maintained by Michael Diggles
last modified 18 May 2004 (PD)
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