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Minutes of the meeting on “Scientific Deep Drilling Investigations in Koyna
Intraplate Zone, Maharashtra”, held on 11th April, 2014 at Prithvi Bhavan,
New Delhi
List of participants is at Annexure-I
Dr. Shailesh Nayak, Secretary MoES initiated the meeting by welcoming all the
participants. He appreciated the support provided by all the Indian Scientific
Departments and Universities in this project. He mentioned that in the preparatory
phase, a considerable amount of work has been done by NGRI under the guidance of
Prof. H.K. Gupta and Dr. Mrinal Sen, then Director, NGRI. At present, the project is in the
phase of transition from preparotory phase to the main phase, where the deep boreholes
are to be drilled. He also mentined that since CCEA has now cleared the proposal to
undertake deep drilling in Koyna, it is important that all the investigations/activities of
the project are identified alongwith the role/responsibility of participating institutions,
so that implementation may be planned.
Dr. Nayak further mentiond that it is an opportunity for all the interested
institutions/ scientists to define their possible roles and participate in the project; the
global scientific community has also shown keen interest to be part of the project.
Prof. Harsh Gupta, Member NDMA and Project Advisor thanked the MoES for its
unstinted and continued support of this important scientific endeavor. He made a
presentation on the history of development of the project and the scientific rationale of
its conceptualization. The scientific rationale of drilling a deep bore hole at Koyna has
been very strongly supported by the International and National community, as
evidenced in the ICDP meeting held at NGRI, Hyderabad and Koyna in March 2011, the
workshop of March 2013 where scientists had a first view of the cores obtained from
drilling at Koyna, and more recently in the ICDP meet commemorating 10 years of ICDP
at Potsdam in November, 2013. He briefly mentioned the upcoming ICDP international
workshop scheduled to be organized from 16-18 May 2014.
Dr. Y.J. Bhaskar Rao, Director CSIR-NGRI and Project Co-ordinator, also thanked
the MoES for support provided to the project. He reiterated the commitment of CSIRNGRI toward the fulfillment of project objectives.
Dr. N. Purnachandra Rao made a presentation on the salient milestones, which
have been achieved since the initiation of project activities. The participants from the
different parts of the country were brought abreast of the major developments in the
fields of borehole drilling and logging as well as surface and airborne geophysical
investigations, which are at various stages of completion.
Dr. Rao also presented a brief summary of geophysical logging and
hydrogeological experiments and broadband seismology. He demonstrated how the
application of double difference and waveform modeling techniques had helped in better
delineation of hypocentral trends and focal mechanism solutions. Determination of fault
plane orientations and precise focal depths in a shallow zone of 4 – 7 km in the Warna
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seismic cluster had enabled selection of the ideal site for scientific deep drilling. An
additional site, though slightly deeper, was also identified south of the Koyna region, in
the region of the first major earthquake of 1967. He further mentioned that in order to
obtain highly accurate hypocentral locations, borehole seismology was planned through
installation of sensors at depth, between 1 and 1.5 km, surrounding the seismic cluster.
He went on to report that two borehole seismometers were already installed and are
functional, while six more were being procured for deployment.
Dr. V.M. Tiwari made a short presentation on the airborne gravity-gradiometry
and magnetic survey and presented the significant findings of basalt thickness and
density contrasts in the basement granites. The Trap thickness has first order
relationship with topography, which has been verified with drilling results.
Dr. P.K. Patro reported the magnetotelluric (MT) work carried out in the region
and explained the conductivity contrasts along two E-W profiles running through two
borehole locations, which corroborate very well with the observations from drilling. He
explained the techniques by which the signal-to-noise ratio was improved. MT data has
brought out various sub-surface structures running from basement to the top.
Dr. K. Arora explained the LiDAR and orthophoto data acquisition scheme, in the
study region, which would contribute to studies of morphotectonics.
Dr. Sukanta Roy presented the progress of drilling and borehole measurements of
heat flow. He gave a summary of the geological log from the first borehole near Koyna
and discussed a number of features observed in the cores from the area. He said that
one of the major findings of the project is a clear absence of sediments between the traps
and the basement in any of the boreholes. Also, the trap thickness which was ~ 1 km on
an average, had variations mostly in the topography, whereas the base of the trap was
more or less flat. This implies that the basement was quite flat prior to the Deccan
volcanic eruption in this region. He also explained how the relatively low heat flow in the
area is commensurate with regional observations, and presented temperature models
up to a depth of 10 km in the region.
Dr. Roy further presented the scheme of the deep drilling program, which would
be finalized during the ICDP workshop. He showed the possible locations of two deep
boreholes, one in the Warna seismic cluster and the other between Koyna and Warna. He
emphasized the need for a stable borehole column to be able to conduct all the
experiments and presented two alternative configurations. He explained the basis for
each configuration taking into consideration several factors such as subsurface geology,
feasibility of directional drilling, maximum expected temperatures, absence of over
pressured zones, sound casing and cementation, environment friendly practices, etc. He
mentioned the various measurements and monitoring studies planned in the deep
borehole(s): seismometer arrays; pore pressure transducers; temperature sensors, etc.
The area falls in the Chandoli National Park and efforts to get necessary permissions are
on, he added.
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Dr. Sunil Singh from PRL showed results of Rb-Sr dating of basement rocks, which
yielded a value of 2484 +/- 85 Ma, in concurrence with those from the Dharwar craton.
Comments and remarks from participants came as inputs during
presentations as well as during the post-lunch session:
Dr. Amalendu Sinha mentioned that it is important to determine the Young’s
Modulus changing with P-T conditions. Since the rock mechanics is the area of core
competence of the institute, CIMFR, would be happy to get involved in the project and
take up modelling and simulation studies as well.
Dr. Parihar, Director, AMD mentioned that AMD is happy to be associated with
the current activities of the project, i.e. logging etc., and would extend its full support for
future work. He also mentioned that the correlation of logs, geochemical study of the
transition zone and monitoring of Rn emissions are quite important and expressed their
keen interest to undertake these studies.
Mr. D.K. Sinha, AMD emphasized the need to look carefully at new mineralization
in old basement rocks.
Dr. B.R. Arora complimented the team and advised Dr. Patro to analyze the MT
data in different frequency bands for higher resolution.
Dr. Gopal Dhawan, MECL mentioned that with this project India will have a
chance to lead the world. Knowledge of earthquakes would lead to improved planning
and construction practices. Borehole imaging with ATV to establish listricity of faults is
recommended. He offered MECL’s support for the project.
Mr. K. Bhattacharya offered ONGC’s involvement in the well planning. He
mentioned that expertise to drill upto 5 km depth is available in the country, and ONGC
shall extend its total support to the national programme.
Dr. Wadhwan, GSI, informed about the opening of the Centre for Research in
Volcanology recently established by GSI, Pune. He stressed the importance of re-logging,
petrography, petrochemistry, geomorphology and lineament mapping and offered the
expertise of GSI. He requested that the site of the deep borehole be earmarked for an
excursion tour during IGC 2020.
Dr. R.K. Kamble, CWPRS explained that their experience for hydraulic research in
Koyna-Warna-Kolkewadi dam sites could provide valuable inputs.
Prof. Pawar, Kolhapur University showed interest in chemistry and dates of
water, reconstruction of paleo sea-level. He made an open offer for any kind of scientific
or logistic help that may be required from the Shivaji University.
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Dr. Karmalkar from Pune University, shown his interest in studying the
horizontal correlation of flows as well as quick logging with handheld XRF tool.
Dr. K.C. Tiwari, MS University, Vadodara expressed interest in study of
discontinuities of in-filling material, which could be related to history of crustal
deformation.
Dr. Prabhas Pande stressed on the importance of location and depth of deep
borehole vis-à-vis faults active in the basement, their surface traces. He suggested to
undertake active fault mapping in Koyna area.
Dr. Subir Das, IMMT showed interest in petrogenetic and geochemistry of core
sample.
faults.
Dr. Biswal, IITB suggested Borehole imaging with ATV to establish listricity of
During lunch, the posters on different aspects of the project work were viewed
with enthusiasm by the participants and generated further discussions.
Dr. Shailesh Nayak expressed satisfaction over the progress and the future plans
being worked out for the project. On the way forward, he advised that while the plans for
deep drilling are in progress, the earthquake studies and the detailed analyses of core
samples should be continued. As this is a prestigious and unique opportunity for India to
provide global leadership on an extremely important topic of scientific and societal
relevance, he expressed happiness over the overwhelming response and support to the
project from the earth science community of the country.
Dr. B.K. Bansal summed up the proceedings of the meeting. He thanked the
participants for showing their keen interest and providing very valuable inputs for the
deep borehole programme. He summarized briefly the plans for the near future and the
commitment of the Ministry towards the science objectives of the project. Dr. Bansal also
requested the participants to prepare a short write up on the work they would like to
undertake, as a part of the mega project, and send the same to MoES within 3 weeks.
The meeting ended with a vote of thanks to the Chair.
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Annexure-I
List of Participants
S. No.
1.
2.
3.
Name
Dr. Shailesh Nayak
Dr. Harsh Gupta
R. K. Kamble
4.
Dr. Ajeet P. Pandey
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Dr. Prasanta K. Patro
Dr. Sukanta Roy
Dr. Babita Sharma
Dr. Kusumita Arora
Dr. V. M. Tiwari
Dr. Anil K. Gupta
Dr. Prabhas Pande
Dr. B. R. Arora
Dr. Subir Kumar Das
Prof. T. K. Biswal
Prof. K. C. Tiwari
Dr. N.R. Karmalkar
17.
Prof. N.J. Pawar
18.
19.
20.
21.
22.
23.
24.
25.
Dr. N. Purnachandra Rao
Dr. Y. J. B. Rao
Dr. B. K. Bansal
Dr. Rahul Mohan
K. Bhattacharya
Dr. K .K .K.Singh
Dr. A. Sinha
Mr. Samudra Mitra
26.
27.
28.
Dr. Gopal Dhawan
P. S. Parihar
Dr. S. K. Wadhawan
29.
30.
31.
32.
33.
34.
35.
36.
37.
Dr. D.K. Sinha
Dr. Sumer Chopra
Dr. H.S. Mandal
Dr. Sunil K. Singh
Mr. Anup K. Sutar
Mr. Vamdev Pathak
Dr. M. Verma
Mr. Yogesh Sharma
Dr. Arun Gupta
Organization
MoES
NDMA
Central Water& Power Research
Station, Pune MoWR.
India Meteorological Department,
Ministry of Earth Sciences.
CSIR- NGRI.
CSIR - NGRI
MoES
CSIR- NGRI
CSIR- NGRI
WIHG, Dehradun
Ex.DDG,Geological Survey of India
MoES, Seismology Division.
CSIR- IMMT, Bhubaneswar
IIT Bombay
M. S. University of Baroda, Vadodara
Department of Geology, University of
Pune.
Shivaji University, Vidyanagar,
Kohlapur, Maharashtra.
CSIR- NGRI
CSIR - NGRI
MoES
NCAOR
ONGC
CSIR- CIMFR Dhanbad
CSIR- CIMFR Dhanbad
Dy. GM(Geophypics)
MECL Nagpur
CMD, MECL, Nagpur
Director, AMD
Director General, Geological Survey of
India, Kolkata.
SO/H Head P.M.S.G. AMD Hyderabad
Scientist – E, MoES
Scientist, IMD, MoES
Physical Research Laboratory
MoES, New Delhi
MoES, New Delhi
MoES, New Delhi
Dy, G.M.(BD&C), MoES, New Delhi.
MoES
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