Earthquake Monitoring and Research

Portable Seismic Network

August 15, 2007

 

Google Earth Maps of Crandall Canyon and Locations of Portable Stations

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Table1

Digital Instrumentation* with Onsite Recording
Station Name

 

Location (WGS84datum)

 

Sensor DAS S/N
Lat. N Lon. W Elevation (ft)
CM1 39° 27.99´ 111° 14.08´ 9,062 Reftek 130 MEMs 936b
CM2 39° 28.13´ 111° 13.06´ 10,553 Reftek 130 MEMs 936a

* Portable REFTEK-130 DAS with External MEMs accelerometers

 

Table 2

Analog Telemetered Stations
Station Name

Location (WGS84datum)

Sensor Seismometer Parameters
Lat. N Lon. W Elevation (ft) Rc Rd Gain
CM3 39° 26.78´ 111° 12.86´ 10,476 Mark Products L-4 5500 4311 1600
CM4 39° 30.53´ 111° 15.68´ 9,072 Mark Products L-4 5463 7891 1600
CM5

39° 28.04´

111° 8.90´ 7,765 Mark Products L-4 5495 4337 1600

* Rc- data coil resistance in ohms

Rd- damping resistance

 

 

 

 

 

 

Field Notes

August 10, 2007

Five stations were installed between Tuesday, Aug. 7 and Thursday, Aug. 9.   The first two were stand-alone RefTek 130 digitizers with external MEMS accelerometers.  The last three were our analog portable system with Mark Products L-4s and UUSS VCO.    Telemetry for these three stations was brought on-line at 12:00 MDT Aug 10.   For installation purposes we named the sites as CM1-5 (for Crandall Canyon Mine 1-5) with the number reflecting the order in which the site was installed.  Detailed information for all stations is contained in the above tables.  General comments follow:

CM1 - installed early evening 8/7/07.  Soil site directly on top of UUSS original epicentral locations, a short distance west of the mine. The MEMS is buried in tightly packed soil beneath the electronics/battery enclosure.  Solar panel mounted nearby.   Site is very close to the helicopter staging area.  Sensor is accurately oriented and leveled and channels 1-3 on the DAS reflect the Z, N, and E components of the sensor.

CM2 - installed ~ 12 noon 8/8/07 directly on top of the collapse area and a short distance east of the drilling area.  The MEMS was bolted to bedrock.  Recording system and battery in adjacent rubbermaid tub.   Same sensor orientation and channel mapping as CM1.

CM3 - This site was installed late afternoon 8/8/07 with a single component L-4 one mile south of CM2. This is a soil site and is co-located with a radio telemetry relay.

CM4 - Installed morning of 8/9/07. Single component L-4. This is a soil site located approximately 5 miles NW of mine for azimuthal control.

CM5 - Installed late afternoon 8/9/07. Single component L-4. This is a bedrock site approximately 5 miles east of collapse for azimuthal control.

Data were downloaded from the RT130 sites mid-day on Thursday Aug 9.

 

Pictures

CM1

CM2

CM3

CM4

CM5