Thornton Hospital Site
CLC project

Based on "Orientation of Borehole Seismic Stations", by Mehrzad Maghsoudlou, (SDSU Dept. of Geology Senior Thesis, Spring 2001)

Aerial photo

 

Orientation of the sensors:

CHANNEL

DEPTH (meters)

INCLINATION

AZIMUTH

HLZ 0 0 0
HLN 0 90 0
HLE 0 90 90
HL7 0 0 0
HL8 0 90 0
HL9 0 90 90
HL4 45 0 0
HL5 45 90 79
HL6 45 90 349
HL1 91 0 0
HL2 91 90 192
HL3 91 90 102


Notes:
Depth is from surface. Inclination is from vertical. Azimuth is clockwise from North.
Blue indicates surface; orientation determined directly with an error likely less than 3 degrees
Green indicates orientation determined by tilt of sonde in borehole. Borehole angle is less than 2
degrees as measured by log tool and tilt is likely less than 5 degrees given diameter of the borehole
sonde.
Red is determined from comparison with surface sensors with known orientation and with
particle motion from known events. Estimated maximum error is 5 degrees with respect to the
surface instruments.

Rotated data - corrected to Z,N,E for all instruments (Hector Mine - Oct 16 1999):

depth (meters)

instrument

vertical

north-south

east-west

0

FBA

HL_FBA_0_Z HL_FBA_0_N HL_FBA_0_E

0

Wil

HL_0_Z HL_0_N HL_0_E

45

Wil

HL_45_Z HL_45_N HL_45_E

91

Wil

HL_91_Z HL_91_N HL_91_E

all data (gzipped, tar)


Notes:
Depth is measured from surface. Instrument type is Wilcoxon (Wil) or Kinemetrics FBA (FBA). Files are 140 seconds long at 100 sample per second and begin before the P wave. Data have been demeaned. File format is Seismic Analysis Code (SAC) ascii format (30 line header followed by data). Event: Hector Mine on day 289 of 1999.

Plots.

Hector Mine event

Hector Mine rotated to radial and tangential

Hector Mine North_South filtered

Hector Mine radial_tangential_filtered

Seismic Analysis code macro

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