This is one of a collection of digital files of a geographic information system of spatially referenced data related to the USGS Coastal and Marine Geology Program "Monterey Bay National Marine Sanctuary Project" <http://walrus.wr.usgs.gov/mbms>. The data were collected and analyzed between 1994 and 2000.
Ross, Stephanie L. , and Wong, Florence L. , 2001, EQRELOC - relocated earthquake hypocenters in the offshore Monterey Bay area:.This is part of the following larger work.Online Links:
Wong, F.L., and Eittreim, S.E., 2001, Continental Shelf GIS for the Monterey Bay National Marine Sanctuary: U.S. Geological Survey Open-File Report 01-179, U.S. Geological Survey, Menlo Park, CA.Online Links:
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 5.610235904774
Ordinates (y-coordinates) are specified to the nearest 5.610235904774
Planar coordinates are specified in Meters
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is GRS1980.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/298.257.
Lines connecting the "before" and "after" location of an earthquake are described in the arc attribute table EQRELOC.AAT
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EQRELOC.PAT: point attribute table
COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME
25 EVENTID 4 5 B -
29 BEFAFT 6 6 C -
35 DATE0 8 8 F 0
43 TIME0 8 9 F 2
51 LAT0 4 7 F 4
55 LON0 8 9 F 4
63 DEPTH_KM0 4 5 F 2
67 MAG0 4 3 F 1
71 RMS0 4 1 B -
75 DATEHHMM 8 12 F 0
83 DATE 8 8 F 0
91 TIME 8 9 F 2
99 LATITUDE 4 7 F 4
103 LONGITUDE 8 9 F 4
111 DEPTH_KM 4 5 F 2
115 MAG 4 3 F 1
119 GAP 4 3 B -
123 RMS 4 4 F 2
EVENTID user-assigned number that relates "before" point
to "after" point and to line connecting them
BEFAFT "before" are original points from NCEDC,
"after" are points recalculated with VELEST model
DATEHHMM relate key yyyymmddhhmm concatenated from DATE0 and TIME0
DATE0 origin date: yyyymmdd from catalog
TIME0 origin time: hhmmss.ss from catalog
LAT0 latitude (decimal degrees) from NCEDC catalog
LON0 longitude (decimal degrees) from catalog
DEPTH_KM0 depth (kilometers) from catalog
MAG0 coda magnitude from catalog
DATE recalculated origin date; usually same as DATE0
TIME recalculated origin time
LATITUDE recalculated latitude (decimal degrees)
LONGITUDE recalculated longitude (decimal degrees)
DEPTH_KM recalculated depth (kilometers)
MAG recalculated? coda magnitude
GAP azimuthal angle between hypocenter and recording station
RMS root mean sqare of residuals of recalculation of
origin time
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EQRELOC.AAT: arc or line attribute table
COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME
33 EVENTID 4 5 B -
37 LENGTH_M 6 6 I -
43 DATE0 8 8 F 0
51 TIME0 8 9 F 2
59 LAT0 4 7 F 4
63 LON0 8 9 F 4
71 DEPTH_KM0 4 5 F 2
79 RMS0 4 1 B -
83 DATEHHMM 8 12 F 0
91 DATE 8 8 F 0
99 TIME 8 9 F 2
107 LATITUDE 4 7 F 4
111 LONGITUDE 8 9 F 4
119 DEPTH_KM 4 5 F 2
123 MAG 4 3 F 1
127 GAP 4 3 B -
131 RMS 4 4 F 2
LENGTH_M length of arc (meters)
the remaining items are identical to those described under EQRELOC.PAT
Florence L. Wong
United States Geological Survey (USGS)
Geologist, GIS Coordinator
USGS., MailStop 999, 345 Middlefield Road
Menlo Park, CA 94025-3561
USA
(650) 329-5327 (voice)
(650 329-5190 (FAX)
fwong@usgs.gov
These data are intended for science researchers, students, policy makers, and the general public. The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information about the shallower areas of the Monterey Bay National Marine Sanctuary.
Northern California Earthquake Data Center (NCEDC)., 1997, Northern California Earthquake Catalog: NCEDC, Berkeley, California.
Ross, Stephanie L. , Ryan, Holly F. , and Stephenson, Andrew J. , 1998, San Gregorio Fault zone studies offshore Half Moon Bay and Monterey Bay, CA: Eos, Transactions of the Amerian Geophysical Union v. 79, p. F613, NCEDC, Berkeley, California.
Kissling, Edi, Kradolfer, Urs, and Maurer, Hansrudi, 1995, Velest User's Guide - Short Introduction: none none, Institute of Geophysics, ETH, Zurich, Switzerland.
Not determined.
Not determined.
NCEDC data were requested for magnitudes 1 and greater. Magnitude values of less than 1 appear because the search engine uses a different measure of magnitude than the coda magnitude which appears in the data set (S.L. Ross, sross@usgs.gov, oral communication, 2000). The RMS0 values were not retained from the download.
Chain-node topology present. All of the data are derived using the same methodology and processing.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- Please recognize the U.S. Geological Survey (USGS) as the source of this information.
Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data.
The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials.
This information is not intended for navigational purposes.
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
United States Geological Survey (USGS)
Geologist, GIS Coordinator
USGS, MailStop 999, 345 Middlefield Road
Menlo Park, CA 94025-3561
USA
(650) 329-5327 (voice)
(650) 329-5190 (FAX)
fwong@usgs.gov
USGS Open-File Report 01-179
Please recognize the U.S. Geological Survey (USGS) as the source of this information.Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials.
| Data format: | export file of EQRELOC with attributes in format ArcInfo Export (.e00) (version 8.0.2) Size: 0.1 megabytes |
|---|---|
| Network links: |
<http://geopubs.wr.usgs.gov/open-file/of01-179> |
United States Geological Survey (USGS)
c/o Florence L. Wong
Geologist, GIS Coordinator
USGS, MailStop 999, 345 Middlefield Road
Menlo Park, CA 94025-3561
USA
(650) 329-5327 (voice)
(650) 329-5190 (FAX)
fwong@usgs.gov