Analog Seismograph - CSIR - CSIO Technology

Analog Seismograph

Recently I visited CSIR technofest 2010 showcased by Council of Scientific & Industrial Research, New Delhi, at India International Trade Fair in New Delhi, the Capital of India. In this technofest, I have seen a technology " Analog Seismograph" which was developed by CSIO (Central Scientific Instruments Organisation, Chandigarh) under the aegis of CSIR, New Delhi, India.

Portable Analog Seismograph has been designed and developed to monitor process and record the field seismic data from remote sites. The electrical signal produced by the short period seismometer (seismic sensor) in response to ground motion is fed directly to the portable analog recorder.

The recorder processes the seismic signal, which is extremely low in amplitude and is highly corrupted with dominant background noise. The whole seismic data is tagged with the internally generated time clock, which can be synchronized with reference ATA Timing Signal transmitted by NPL, New Delhi. The duly processed data tagged with timing information, is finally recorded on a smoked paper wrapped on a drum.

 
Specifications of this instrument

1	Voltage Gain	42db to 96 db in a step of 6 db.
2	Filters
	High Pass	0.2, 5.0, 10.0
	Low Pass	5.0, 12.5, 25.0, 50.0
3	Time Marks	Hour, Minute, 10 Seconds, 1 Sec. (Adjustable Amplitude)
4	Drum Rotation	30, 60, 120 mm per minute
5	Trace Seperation	1, 2, 4, 8 mm per rotation
6	Record Duration	Max. 120 hours, Min. 4.0 hours
7	Internal Supply	Rechargeable 60 AH batteries
8	Power Consumption	12 V DC, 80.0 ma, operates continuously for  Approx. 30 days on 60 AH Lead Acid Battery.

Salient Features of this portable instrument

The analog recorder has been matched with seismometers of different manufacturing concerns viz- model S-13/ S-500 of M/s Teledyne Geo Tech USA, model SM-3 M/s Special Design Bureau, Russia and model MK III of M/s Sensonic USA.

- It is battery powered, portable and is fully field worthy. It has less running cost and is simple in operation.

- It produces seismograms without any separate data retrieval unit. The seismogram is easily decipherable at a quick glance.

- It can record the events of several hours duration without running short of storage media.

- Because of the facilities for programmable drum speeds and trace separations, the seismologist can record field data on a single smoked paper for a period varying from 3.5 hours to 115 hours.

-  Different sets of time marks (hour, minute and second) are switch selectable at the front panel.

- Ten switch selectable gains at a step of 6 db are provided for selection of sensitivity. Four low-pass and three high pass filter positions is switch selectable for selecting a specific signal of interest.

Applications of this instruments are useful to any country in earthquake times.

a) Monitoring of major and micro Earthquakes. 

b)Study of Preshocks and After shocks. 

c) Seismic noise Survey & Microzonation 

d) Site selection survey for vital structures. 

e)Strong Motion Recording & Studies.

f) Studies on Induced Seismicity.

Field Trials have done and technical Evaluation Report has also seen and checked with imported one and this machine gives same performance as that of imported one.

IMD - New Delhi., NGRI – Hyderabad, Sardar Sarovar Dam, Bharauch (Gujrat), Geo Resource Department of Delhi University, Central Water Commission (CWC), Pune, Nuclear Power Corporation (NPC), Bombay and many universities and research institutes are using this instrument.articlebase