USGS Professonal Paper 1096 - IRIS

MONTANA--Continued
Billings, MT
INSTRUMENTATION
Code
Type
Seismometer
Component
Galvo
\(sec)
Type
recording
Magnification
at Te
Remarks
LAO, LCI-4,
LDl-4, LFl-4,
LFI-4: Hall-Sears lO-lA----- z
Geotech JSOSA--------- Z,NS,Ew
1.0
20.0
Develocorder.
digital.
Each station has 15 additional
stations in
an array within 3.5 kID
of the central station.
Ihe1r 1nstrumentat10n
is the same as that of
the LB stations. LCI
has only 14 additional
stations.
Do.
LB}-4 Hall-Sears lO-lA----- z
1.0
Digital------
Do.
Timing system: A WWV synchronized time-of-day Hyperion Industries, Model HI-140, time-code generator and Motorola SLN-6039D
!lasL .. , Osc UhLor.
System response CUrves: See figure 8, p. 365.
SHORT HISTORY
LASA was established to explore the possibility of using large arrays fOr seismic discrimination, specifically
discriminating bet\!o'een earthquakes and blasts. Experimental work on the dynamics of large arrays continues. The Corporation
puts out daily teleseismic event reports, weekly near-regional reports, and biweekly strip-mine blast reports.
The central Site, LAO, is sometimes coded LA~.
184