Seismicity Programme
The key objectives of the programme are:
During the year, 50 projects have been evolved and supported for monitoring
of seismicity, crustal deformation studies, seismotectonic studies and vulnerability
analysis in selected region. Also, support was continued to the following field
oriented facilities set up under the Seismicity Programme:
The microzonation experiment initiated for Jabalpur urban region has been successfully
completed and a report is now ready. A microzonation map and a preliminary risk
map for Jabalpur have been prepared. Based on the model developed for Jabalpur
region, micozonation studies have been initiated for other urban centers including,
Delhi, Guwahati and Bangalore. While the microzonation work of Guwahati is in
advance stage and expected to be completed by June 2005, the microzonation work
for Delhi and Bangalore is also in progress. Achievements under the selected
ongoing and completed projects are highlighted below:-
Satellite Captures Pre-Earthquake Thermal Anomalies
Under the project entitled “Development of remote sensing
based geothermic techniques in earthquake studies” sanctioned to IIT,
Roorkee, a Satellite Earth Station has been established to study the possible
correlation of earthquake occurrence with change in temperature. Satellite remote
sensing can record emission from the earth’s surface and has brought out
interesting observation in this direction. Data from sensors like Advanced Very
High Resolution Radiometer (AVHRR) on board NOAA – series of satellites
were used to map the Land Surface Temperature (LST) conditions before and after
three major recent past earthquakes around the world. Thermal infrared NOAAAVHRR
datasets were used to study the thermal scenario before and after the Bhuj earthquake
in Gujarat, India, the Boumerdes earthquake in Algeria and the Bam earthquake
in Iran. In case of Bhuj earthquake, AVHRR-NOAA showed the presence of thermal
anomaly associated with the tectonically active region of the Gujarat state,
India, before the devastating Bhuj earthquake of 26 January 2001. The maximum
rise in thermal regime of the area appeared on 23 January 2001 just three days
before the earthquake event, bringing increase in temperature to around 7°C
above normal compared to the surrounding region. The anomaly was seen to disappear
just after the earthquake.
Site Response Survey in Delhi (NCR) for Seismic Microzonation study
Site specific studies were carried out in Delhi and neighbourhood by deploying ten portable Seismographs (SP) for a period of about six months in two phases. The first phase of the fieldwork was completed by WIHG in July 2003 covering more than 160 sites in the city over an area of approximately 650 sq. km. Locations of different sites are shown in Figure 2.17. During this field survey, weak motion from earthquakes and microseisms were recorded. It was noted that seven local events (within 25 km of Delhi city) were recorded. The analysis of these data has been completed using methods like Nakamura technique and Reference site method. The predominant period and the amplification factors of the sedimentary column have been obtained for different sites.
GIS Based Subsurface Geotechnical Model of Bangalore
This study is aimed at mapping geotechnical data by developing a GIS based subsurface model. A digitized Bangalore map forms the base for this model. A huge amount of authentic geotechnical data of Bangalore city along the depth (Location details, physical properties, index properties, strength properties of soil and rock properties) was collated from borehole investigations carried out by expert organizations. So far, 850 borehole data has been keyed into the database, spatially distributed all over Bangalore. The bore depth ranges from 6-40m, with an average depth of 15m. These boreholes are developed as 3-D objects projecting below the Bangalore map. These 3-D projections are manifested by overlapping of several layers of spell, in which each donut represents 0.5m depth of bore below ground level (Figure 2.18). Geotechnical data for each borehole in the model, the geotechnical properties at that point and depth of subsurface are displayed. Also, the model provides an option to view the complete bore log data along with properties table in a single and standard view.
GIS Based Subsurface geotechnical map of Delhi
A strong database of 2000 boreholes ranging from 3m to 50m, pertaining to subsurface geotechnical properties of soil and rock have been prepared based on inputs from various expert organizations. The database includes location details, physical, index and strength properties of soil and rock. Around 1000 boreholes have already been attached to a digital map in GIS format along with the database of each of the boreholes. All the boreholes will be put on the GIS Map to see the spatial distribution. The analysis of the database will help in deriving the following:
GPS aided Crustal Deformation Studies
A National Programme on Global Positioning System (GPS) was launched during 1997-98 for monitoring the crustal deformations due to earthquake occurrence and other geodynamic phenomena. As of now, 30 permanent GPS Stations have been established all over the country (Figure 2.19), and initiative is being taken to establish more permanent stations. A number of organizations are also deeply involved in studying the crustal deformation process in campaign mode (Figure 2.20). Some significant results related to the movement of Indian Plate and velocity vectors have been obtained. GPS derived velocity and deformation rates in the Himalayan arc vary from west to east suggesting that the deformation mechanisms in Ladakh, Garhwal, Kumaun and Sikkim Himalayas are different and are to be treated differently. GPS derived extension vector between the Himalayan sites and Lhasa is consistent with the east west extension of southern Tibet. Kutch GPS results give post seismic deformation consistent with Bhuj rupture zone as GPS measurements were made after the 2001 earthquake. GPS measurements in the northeast India seem to indicate that there is strong lateral variation in the convergence rates in northeast Himalayas.
Mission Mode Project in Seismology
The mission mode project is an attempt to provide value added products for earthquake disaster mitigation through technological interventions with the technical support of several Institutions. Based on the activities identified by the Expert Committee and approval of the EFC, following projects were sanctioned:-
High resolution data for determining Crustal structure of the North
Eastern region
At present, more than 25 Broadband Seismic Observatories are being maintained by various Institutions in North Eastern India. During the last few years, the observatories have generated the high quality broadband data. Using the data acquired by the seismic stations in the region, an attempt was made for determining the crustal structure beneath the seismic stations located in different geological units like Shillong plateau, Mikiri Hills, Assam valley and in the foothills of Himalaya in Northeast by using the state-of-the-art techniques like the receiver functions.
Dynamic Properties of Soils and Liquefaction Behaviour of Sands
An experimental program was devised to evaluate the dynamic properties as well as the liquefaction behaviour of the soil samples collected exclusively from the sites close to epicenter of Bhuj earthquake, Sabarmati river belt in Ahmedabad and meizoseismal region of Shillong Plateau, Assam, using the state-of-the-art Cyclic triaxial testing facility. The major part of the triaxial testing facility (Figure 2.21) was developed indigenously. Preliminary investigations regarding the characterization of the different soil samples, dynamic properties and cyclic behaviour of sands were obtained from cyclic triaxial tests. Evaluation of liquefaction potential of sandy soils and characteristics of liquefied sands during Bhuj earthquake has also been completed.
Study of Ultra Low Frequency (ULF) electromagnetic precursors of earthquakes
A study has been carried out to establish possible correlation of emission of electro-magnetic waves with earthquake occurrence. It has been reported that association of anomalies in the geomagnetic field with the seismic activity is almost confirmed from the results obtained under the above project.
The signals are also found to be of precursory nature. However, the results are still indicative and not conclusive. More observing stations can be useful for finding the direction of earthquake with the analysis of amplitude gradient of magnetic field. The attenuation of the electromagnetic ULF waves were studied in detail and it was found that the wave could travel more than 1000 km. The monitoring of ULF magnetic field is also helpful for study of magnetospheric phenomena. Two projects related to VLF/ULF monitoring are being sanctioned.
Intensification of Research in High Priority Areas (IRHPA)
IRHPA is a complementary programme to the SERC programme, which aims at setting up of units/core groups around eminent scientists and major National Research Facilities to nucleate research activities in various areas. The scheme has contributed to augment general R&D capabilities at academic institutions and national laboratories in the areas of Crystal Structure, Robotics, Laser Spectroscopy, Structural Biology, Surface Science & Technology, Computational Fluid Dynamics, Technical Acoustics, Geocentrifuge for Engineering applications etc.
A major project was funded jointly to the Indira Gandhi Centre for Atomic Research,
Kalpakkam and NIMHANS, Bangalore for indigenous development of a single channel
and subsequently a multichannel MEG system complete with cryostat, electronics
and control instrumentation inside a custom built magnetically quiet room (MQR).
This project would be implemented in two phases. In the first phase, which would
be completed in two years, the MQR, capable of attenuating low frequency electric
and magnetic noise by 60 to 80 dB (a factor of 103 to 104) would be established.
A single channel MEG instrument complete with the SQUID, read out electronics
and a FRP cryostat mounted on a manipulator capable of XYZ movement for mapping
the field due to several cortical locations sequentially would be developed.
In the second phase, which would be the last two years of the project, a multichannel
MEG instrument with about 64 channels would be developed. This would enable
the recording of neuromagnetic activity simultaneously from the entire cortex
without the necessity to move the cryostat and would enable tracking of events
with millisecond response and with a spatial resolution of a millimeter.
The IRHPA unit on “social biology of insect” with Prof. R.Gadagakar, Centre for Ecological Sciences, IISc, Bangalore has been extended for two years. Another IRHPA unit on “evolution and genetics” is being examined to be set up at Zoology Department, Mysore University, Mysore with Prof. H.A.Ranganath to intensify research in the area.
All the three constituent laboratories of the Facility for Research in Technical Acoustics (FRITA), funded by DST under its IRHPA scheme, have been functioning full stream. During this 6th ongoing year, all continuing consultancy projects have been completed and 12 new projects have been taken up in order to help industry to design for quietness and to quieten their machines, vehicles and processes. An automotive muffler has been designed and developed in one of the projects (Figure 2.22). Two short-term training courses were held. 20 papers were published in refereed journals and/or presented in conferences in addition to 49 published already. Eight students completed their research or ME thesis in the field of Technical Acoustics. FRITA continued to give leadership to the National Committee for Noise Pollution Control.
A National Stable Isotope Facility for Research in basic and applied sciences is being set up at the Centre for Water Resources Development and Management (CWRDM), Kozhikode with a total project cost of Rs.3.98 crores including Kerala Government share of Rs.50 lakhs, for a period of 5 years. Under this facility, 8 institutes are participating with 14 collaborating projects.
The first training workshop is being organised at NIH, Roorkee. A “Center
for Soft Computing
Research” aimed at promoting basic research and manpower development is
being set up at the Indian Statistical Institute, Kolkata.
A National Facility for Texture and Orientation Imaging Microscopy (OIM) has
been jointly set up by DST, DRDO and IIT, Mumbai at IIT, Mumbai. The SEM-OIM,
and XRD with texture goniometer, have now been successfully commisioned. Complementing
facilities such as TEMOIM, and texture analysis packages are already available
at IITB. With the commissioning of SEM-OIM, a comprehensive facility for detailed
texture studies is now available at IIT, Mumbai. Two specifically designed technical
and awareness workshops for training and guidance to potential users of this
facility from academic & research institutions and industry, are likely
to be organised during 2004 -2005.
Some other new programmes sanctioned during the year are:
CERN-India Collaborative Projects
DST (along with DAE) continued its funding of the two collaborative projects at CERN, Geneva to participate in two major experiments at the upcoming Large Hadron Collider. Significant progress was reported in both the projects.
In the first project, viz. the Compact Muon Solenoid (CMS) Experiment in which
TIFR, Mumbai; BARC, Mumbai; Panjab University, Chandigarh; and Delhi University
were participating, all the 432 Detector Modules had been fabricated, tested
with radioactive sources and shipped to CERN. All the 72 hanging structures
had also been fabricated and shipped to CERN and the detector modules were ready
for mounting inside the CMS detector. The Indian group had also been enlarged
with the inclusion of Visva Bharati group. The Indian groups were also effectively
contributing towards preparation of the Physics TDR, software development and
development of Grid Computing.
In the second, ALICE Experiment (A Large Ion Collider Experiment) also, where
Indian groups from VECC, Kolkata; SINP, Kolkata; Institute of Physics, Bhubaneswar;
Panjab University, Chandigarh; Rajasthan University, Jaipur; Jammu University;
Aligarh Muslim University and IIT, Bombay were participating, significant progress
was reported. The smaller Photon Multiplicity Detector (PMD), which had been
fabricated and installed at the Brookhaven National Laboratory, USA as a run-up
to the bigger detector to be fabricated for the ALICE Experiment, was used in
data taking and the physics data analysis was in progress. Regular production
of ALICE PMD modules had also started and the first unit module had already
been tested at CERN. As in the CMS case, the Indian groups were also contributing
extensively towards software development,