Cruise Information EW9415
LARSE '94

 

Part of the Los Angeles Region Seismic Experiment (LARSE), this study acquired deep-crustal multichannel seismic-reflection data in the Inner California Borderland, collecting approximately 1250 km of 40-fold MCS reflection data. The results of this study were to be combined with reprocessed industry seismic reflection data from the San Fernando Valley to provide information on the subsurface structure of the Santa Monica Mountain-Elysian Park thrust ramp and the Northridge earthquake fault system as will as the San Fernando Basin and its underlying crust.

Field (shot) data are available at IRIS (go to http://www.iris.washington.edu/data/assembled_request.htm, data set number = 02-006; data set name = LARSE MultiChannel Seismic Reflection). Any publication using these data should acknowledge the U.S. Geological Survey and the Southern California Earthquake Center as the original data sources.

Chief Scientist:

Thomas M. Brocher

Principal Investigators:

Thomas Henyey (NSF 9416774, 9416773)
Gary Fuis
David Okaya (NSF 9416773)
Robert W. Clayton

Data Originating Institutions:

U.S. Geological Survey
California Institute of Technology
University of Southern California
University of California, Los Angeles
Southern California Earthquake Center

Funding Agency:

National Science Foundation
Southern California Earthquake Center
U.S. Geological Survey

Access:

Unrestricted access.

Data Classes at UTIG:

Processed

Data Types at UTIG:

MCS

LDEO cruise page

seismic sections
map
program summary information
scientific references
seismic acquisition parameters
processing history
line start/end dates and times
available SEG-Y data - Processed
available SEG-Y data - Field
related documents

 

Select a cruise:

Program Summary Information

NGDC Number

Platform

Maurice Ewing

Platform Operator

Lamont-Doherty Earth Observatory

Beginning Date

1994-10-13

Ending Date

1994-10-21

Start Port

Long Beach, California

End Port

San Diego, California

Line Names

MCS: LARSE01R, LARSE02, LARSE03E, LARSE03W

Location

North Pacific

Navigation

LDEO field data

Cruise Report

PDF

Links

http://www.data.scec.org/larse/larse.progress.html

Comments

An abridged time-stamp file, Appendix_1.nav.txt, was used to place navigation and time in the SEG-Y headers.

Scientific References
Brocher, T., Clayton, R., Klitgord, K., Bohannon, R., Sliter, R., McRaney, J., Gardner, J., and Keene, J., 1995, Multichannel seismic-reflection profiling on the R/V Maurice Ewing during the Los Angeles Region Seismic Experiment (LARSE), California, U.S. Geological Survey Open File Report 95-228, p. 73.
URL: http://geopubs.wr.usgs.gov/open-file/of95-228/of95-228.pdf

ten Brink, U.S., Drury, R.M., Miller, G.K., Brocher, T., and Okaya, D., 1996, Los Angeles Region Seismic Experiment (LARSE), California off-shore Seismic Refraction data, U. S. Geol. Surv. Open-File Rept. 96-27, p. 29.

ten Brink, U.S., Zhang, J., Brocher, T.M., Okaya, D.A., Klitgord, K.D., and Fuis, G.S., 2000, Geophysical evidence for the evolution of the California Inner Continental Borderland as a metamorphic core complex, Journal of Geophysical Research, vol. 5835-5857, p. 5835-5857.

Godfrey, N.J., Fuis, G. S., Langenheim, V. E., Okaya, D.A., and Brocher, T. M., 2002, Lower-crustal deformation beneath the Transverse Ranges, southern California: Results from the Los Angeles Region Seismic Experiment, Journal of Geophysical Research, vol. 107(B7), p. ETG 8-1 to 8-19, DOI: 10.1029/2001JB000354.

Fisher, M. A., Normark, W. R., Langenheim, V. E., Calvert, A. J., and Sliter, R., 2004, The offshore Palos Verdes fault zone near San Pedro, Southern California, Bulletin of the Seismological Society of America, vol. 94, p. 506-530.

Baher, S., Fuis, G. S., Sliter, R., and Normark, W. R., 2005, Baher, S., G. S. Fuis, R. Sliter, and W. R. Normark, 2005, Upper-crustal structure of the inner continental borderland near Long Beach, California, Bulletin of the Seismological Society of America, 95, 1957-1969., Bulletin of the Seismological Society of America, vol. 95, p. 1957-1969.

Seismic Acquisition Parameters

Receiver Type

Hydrophone:Streamer

Source Type

AirGun:Bolt

Acquisition System Name

DMS 2000

Acquisition System Type

Seismic Navigation System

GPS

Survey Datum

WGS84

Source to Near Channel (meters)

162.5

Antenna to Source (meters)

87.4

Number of Channels Recorded

160

Number of Cables

Number of Channels Each Cable

Channel Length (meters)

25

Cable Length (meters)

Cable Spacing (meters)

Near Channel Number

Cable Receiver Depth (meters)

10-12 m

Cable Receiver Depth Recorded

Number Source Arrays

FlipFlop Shooting

Source Array Separation (meters)

Source Volume (cubic inches)

8470

Source Pressure (bars)

136.4

Source Number

20

Source Depth (meters)

11-Aug

Processing System

ProMAX

Shot Control

time

Shot Interval (seconds)

20: except Line 3 (strong currents caused an increase in ship speed over the ground decreasing the shot time interval to less than then 19 seconds)

Sample Interval (microseconds)

2000

Record Length (seconds)

16

Compass Birds

Tail Buoy Positioning

Recording Delay

Comments

Analog low-cut filter: 20 Hz
Analog high-cut filter: 250 Hz

General Processing Description
Band pass filtering, automatic gain control (AGC), and water column mute.

Line start/end dates and times

Line

Start date

Start
hr:min:sec

End date

End
hr:min:sec

Start shot

End Shot

Start
field Reel

End
field reel

LARSE01R

1994-10-14

11:55:00

1994-10-15

01:24:00

 

 

LARSE02

1994-10-17

05:17:00

1994-10-18

01:54:00

 

 

LARSE03

1994-10-15

21:45:00

1994-10-16

12:10:00

 

 

To top of page

 

Related Documents
Appendix_1.nav.txt
SEGY_header_navigation.txt
The University of Texas at Austin Institute for Geophysics
Compatible with Firefox 1+ (Solaris, Linux, OSX, Windows), Netscape 7+ (Solaris, OSX), Explorer 5.5+ (Windows)