Vadodara Chapter of SPG (Society of Petroleum Geophysicists) and APG (Association of Petroleum Geologists) organized a series of technical webinars on 10th& 12th September 2020. The objective of the lecture series was aimed towards knowledge sharing amongst the geo-scientific community with an active industry-academia collaboration. The sessions were chaired by Patron, SPG&APG, Vadodara Chapter, ED-Basin Manager Shri H. Madhavan and active participation from members of SPG and APG Vadodara, students from MS University and Kutch University.
The first technical talk on “Principles of Gravity in Petroleum Exploration” was delivered by the guest speaker Sh. J N Prabhakarudu, an Ex-ONGCian, a Domain Expert in the field of Gravity & Magnetic and other non-seismic methods, having rich experience of more than three and a half decades. He has authored three technical books and to his credit has a patent on Microgravity Method for Petroleum Identification in his name.
The session commenced with a brief address bythe SPG Patron Shri H. Madhavan, wherein he welcomed the guest speaker and exhorted the young executives for a proactive and a research oriented approach.
The technical talk by Sh. Prabhakarudu, dealt with different case studies pertaining to gravity anomalies in Cambay, Saurashtra and Vindhyan basins, and their utilities in hydrocarbon prospecting. He also elucidated various advanced techniques in gravity anomaly surveys, viz. Micro-gravity, Borehole gravity, 4D gravity and Full tensor gravity gradiometry.


Two technical talks were delivered by distinguished guest speakers from Academia on 12th September 2020,Prof. M. G. Thakkar, HOD, Dept. of Earth and Environmental Science, KSKV Kutch University, and Prof. Dhananjay Sant, MS University Baroda. The online sessions commenced with a brief welcome address by Shri H.Madhavan.


The first technical talk was on the “Geology of Kutch Basin”by Prof. M.G. Thakkar. Having vast experience and deep understanding of geology Kutch area, he began with explaining the physiographic divisions of Kachchh region.The area is an excellent example of a tectonically controlled landscape, whose physiographic features are a manifestation of the earth movements along the tectonic lineaments of the Pre-Mesozoic basin configuration, which was produced by the primordial fault pattern in the Precambrian basement. Physical features of Kachchh are characterized by the contrasting occurrences of extensive plains and highlands with rugged topography.
- The Ranns
- The low lying Banni plain
- The Hilly region
- The southern coastal plains
Prof. Thakkar also elaborated extensively about the general stratigraphy of the region, and then delving into the tectonic settings of the Kachchh Basin.

Physiographic Divisions of Kachchh Region

The second technical talk was on the topic, “Microtremor Study (HVSR) in Kutch Basin” by Prof. Dhananjay Sant. Heelucidated his research work on Microtremor-Horizontal to Vertical Spectral Ratio (HVSR) technique, as a tool to map the extension of rock outcrop/features in subsurface, and to demarcate distinct rheological contrasts up to shallow depth of 2000m. Microtremor surveys use ambient noise as the signal. Their ability to generate rapid single station records at a required resolution, and the cost effective operations, are some of the incentives of using a microtremor survey.
Prof. Sant then presented his research work in Kachchh region, a maiden attempt to map shallow subsurface rheological interfaces laterally across the Banni Plains and to decode geometry of the antecedent faults associated with the Kachchh Mainland Fault using the microtremor method.
Prof. Sant further clarified that the ambient noise encapsulates fundamental resonant frequency of the sediment layers. These resonant frequencies derived from the microtremors show strong correlation with the velocity of the Rayleigh waves and the thickness of the sediments. For a given fundamental resonant frequency, there exists an empirical relationship between the depth of an interface and the velocity of seismic waves (Vs) for the given interface.

Geological and geomorphological map
of Kachchh Peninsula

with Q-T and M-B interface along Deep Banni Core
The event culminated with the concluding remarks from SPG Patron Sh. H. Madhavan, who thanked the guest speakers for such insightful talks and emphasized in more such Industry Academia collaborations. The event was a grand success attended by more than 130 participants.
President SPG Shri Rajesh Madan, GGM (GP) and Vice President Shri G Ganeshan CGM (Geol) and the Basin Office were instrumental in making the event successful. The vote of thanks was given by Sh. Sanjay Kumar, Secretary, SPG Vadodara Chapter. The event was ably compered by Mr. Vipul Chawla, Jt. Secretary, SPG Vadodara.
SPG Mumbai Chapter organised a technical webinar titled “Fundamentals on Multicomponent” on 21st August 2020 at SPIC-ONGC, Panvel. The session is a part of continuous and relentless efforts of SPG to share ideas and experiences to the geo-scientific community and to express & exchange views on fundamentals on Multicomponent. .

Geophysical field party GP-16
The session was chaired by Shri S K Sharma Officiating President SPG Mumbai Chapter. Shri K. Vasudevan,Vice President APG Mumbai Chapter was the Chief Guest. SPG Mumbai Chapter Office bearers, Geoscientists from different G&G companies like Schlumberger, Emerson etc. and students from different Universitieshad taken part in the webinar.
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Shri M.K.Jain, the learned speaker has a vastwork-experience in ONGC for 36 years.He worked very extensively for Reservoir Characterization for 4 years. He worked 28 years in Processing at different centres including GEOPIC, Jorhat, Baroda,Mumbai in ONGC. He Contributed for HC discoveries in many exploratory locations. He worked for a quite long time at Multicomponent technology in Cambay Basin and one of the Pioneer of this technology in ONGC.
Objectives of the technical presentation:
- Describing the basic elements of the multicomponent seismic processing flow and their benefits.
- Describing different multicomponent seismic acquisition systems.
- Describing the characteristics of different wave modes.
- Orientation analysis
- Coupling compensation
- Rotation
- Splitting of Shear Waves
- CCP binning using Variable Gamma
- PZ summation
- Noise attenuation (e.g. shear on vertical)
- Produce a list of challenges, where multicomponent seismic can provide an uplift
- Listing of areas where multicomponent seismic might further contribute to the advancement of seismic for E&P
- Case Studies of Padra, Kalol fields of Cambay Basin, Assam Arakan Frontier Basin & D1 field of Mumbai Offshore Basin.

Shri P R Balak,Vice President SPG Mumbai Chapter made the opening remark of the technical session. He said that focus to imbibe recent advancements in Multicomponent acquisition and processing in India should be our focussed area to work upon.Shri K. Vasudevan, President, APG Mumbai Chapter elaborated the exploration challenges in Western Offshore Basin. He was also very much enthusiasticabout the processing outcome of recently acquired multicomponent survey in Western Offshore Basin.
The webinar witnessed a prolonged Question & Answer session from the enthusiastic audience and Mr. Jain explained patiently all the queries in detail with his baritone voice. Shri S K Sharma,President,SPG Mumbai Chapter emphasised the simple, detailed approach of Mr. Jain in explaining the basic ideasof Multicomponent Seismic Survey, which itself is a challengingtechnology.

Mr. Pritam Bera, young executive skilfully anchored the program and delivered the vote of thanks.
Team SPG
Mumbai, Chapter
SPG Ahmedabad chapter organized a trip to Geophysical field party GP-16 camping at Valod area, Gandhinagar on 16th Mar'20.

Geophysical field party GP-16
The objective of the field trip was to provide an insight to the members the concepts a 3D seismic data acquisition. The trip provided an opportunity to geologist, reservoirs engineers apart from geo physicists a ONGC, GERMI and GSPC to understand the finer details of field party functioning. Party Chief and the party members took keen interest and apprised the participants about the steps involved in Acquisition and on field processing. The activities were demonstrated live in the field.




The fundamentals of Seismic data acquisition, the objective of the survey, the geometry of the survey was explained and illustrated in a very simple but exhaustive way. The daylong field trip proved to be very educative and enriching experience to all the participants. SPG members got actively involved in technical discussions and got their doubts cleared

The trip ended with a parting note to the Party Chief and the entire crew of GP-16 for the extra efforts taken by them for explaining and demonstrating the field activities. The chapter expresses its deep appreciation and is thankful to all of them. Thanks are due to the coordinator from the Basin for facilitating the trip. The chapter acknowledges with thanks HGS, Baroda for having granted the necessary permission for the trip.
SPG
Ahmedabad Chapter
SPG and APG Vadodara chapter organised a geological field trip to Narmada North, Kevadiya, on 1st February, 2020. The fieldwork was conducted in the Narmada River section near Navagam village.

SPG & APG Team members at the onset of the field trip.
The objective of the fieldtrip was to provide an exposure on the geology of the Cretaceous Bagh Group sequence in Lower Narmada valley. It gave an opportunity to study the detailed lithostratigraphic divisions, boundaries of the units and an opportunity for appraisal of the vertical and lateral lithologic variations. Around 80 members of SPG & APG Vadodara chapter actively interacted with Professor Satish Patel and his team (Assistant Professor and Research fellows) from Maharaja Sayajirao University who guided the entire field trip.


Prof.Satish Patel briefing the participants in the field.
Cretaceous Bagh Group
The Bagh Group rocks are deposited in the ENE-WSW trending pericratonic Narmada rift and represent a complete cycle of sea-level change. The Navagam section is ~307m thick and exposes all the member of the Bagh Group except the Men Nadi Limestone Member and the Mohanfort Sandstone Member. The succession here is tectonically disturbed, moderate-steeply dipping. The Bagh Group rocks here dips SE towards the Statue of Unity and are intruded by numerous dikes and sills of Deccan Traps. Numerous faults are observed in the area genetically related to the strike-slip faulting in the basin. The succession here is uplift along the faults bounded by Deccan Trap on all the sides.






Glimpses from field
The daylong field trip proved to be very educative to all the participants , it gave an insight on the exposures and geology of the Lower Narmada valley coupled with the enrichment on the spot with the vast experience of Prof. Patel.


Team SPG & APG, Vadodara chapter felicitating Prof. Satish Patel on successful completion of the trip.
Participants thanked Professor Satish Patel from MSU who guided the entire field trip with his valuable inputs. Shri S. S. Singh, CGM (GP) gave away memento to Prof. Patel.


Participants enjoying delicious at a local temple.
Organizers acknowledge ED-Basin Manager & Patron SPG-APG, Shri H. Madhavan for encouraging and facilitating the tour. The reconnaissance was done by Prof S K Patel from MSU and Shri Bhupendra Tauk, Secretary APG, Shri Sanjay Kumar, Secretary & Shri Rajesh Upadhyay, Treasurer SPG, Vadodara Chapter on 25th January 2020. Shri Rajesh Madan, President, SPG and Dr. A. K. Singh, Vice President, APG were instrumental in organizing the trip. Thanks are also due to all the participants.
SPG/APG
Vadodara Chapter
Society of Petroleum Geophysicists – India, Jorhat Chapter organized a guest lecture on 26.11.2019 at ONGC, Jorhat on the topic “Shale Oil & Gas exploration in India vis-a-vis International arena”. The talk was delivered by Shri Arun Kumar, Ex-Executive Director of ONGC and attended by over sixty-five G & G professionals and SPG members from ONGC Jorhat.
Session started with welcome address and brief introduction about the objective of the program by President of SPG India, Jorhat chapter- Shri Vishal Shastri, GGM (GP). While introducing the topic President, SPG said that the shale oil & gas exploration is a game changer in the HC production history of The USA, which turned from net importer to self-reliant and tending towards net exporter. He emphasised that such interactive sessions are noble initiatives which give an opportunity for Knowledge Sharing and interaction of young with experienced executives. Shri Arun Kumar delivered the talk on ‘Shale Oil & Gas exploration in India vis-a-vis International arena’. The participative interaction by the house made the talk fruitful and interesting.
Glimpses of the event

Patron, SPG Jorhat chapter Shri Punit Suri welcomes the speaker shri Arun Kumar

President, SPG Jorhat chapter Shri Vishal Shastri delivering welcome address

Participants during technical presentation

Momento being presented to speaker by Patron, SPG
Shri Puneet Suri, ED-Basin Manager & Patron, SPG-Jorhat chapter and Shri Vijay Kumar Gokhale, CGM-Asset Manager gave concluding remarks and emphasised the need of induction of new technologies to arrest the declining production and finding new oil for sustenance of the exploration & production. The meeting concluded with vote of thanks by Shri H N Garg, Vice president, SPG-India, Jorhat chapter.
Society of Petroleum Geophysicists (SPG) & Association of Petroleum Geologists (APG), Vadodara Chapter organised a technical meet on 22nd November 2019. The programme started with two thought-provoking, interactive talks on contemporary issues. The first one was delivered by Shri Jeetendra Tiku, General Manager (Geophysics) on the topic namely "Introduction to Policies governing Oil & Gas industry in India with special reference to Open Acreage Licensing Policies (OALP)". It was followed by another enlightening talk on the topic "Introduction of new technologies in Geophysical Services".
During his presentation, Mr. Jeetendra Tiku elucidated the various complexities pertaining to Important Acts & Rules Governing Hydrocarbon Exploration & Oilfield Development. He explained about Open Acreage Licensing Policy under Upstream Policy Regimes in India.




Shri Praveen Vohat presented an overview of Low frequency Passive Seismics. He also explained the acquisition gamut of LFPS including brief description about new LFPS Seismometer and also about the capability of new data acquisition system 508 XT.
All the SPG and APG members of WON Basin actively participated and benefited from the technical lectures. GGM - Basin Manager Shri H Madhavan in his address explained about the importance of such technical lectures and encouraged to conduct this type of program very often which will help enhancement of knowledge in earth science. The fraternities took this opportunity to bid farewell to Shri Matibar Singh, GGM-HGS, President, SPG, Vadodara Chapter.




The technical lecures were followed by colourful cultural programme and dinner.




In the evening, the members enjoyed a mesmerizing cultural programme, presented by an eminent dance troupe arranged from outside.








This was followed by an interactive sumptuous dinner. The technical programme was compared nicely by Ms Kanika, Programming Officer and Ms Nisha, Geophysicist (S). Vice President SPG Shri Rajesh Madan, Vice President APG Dr. A. K. Singh, Treasurer SPG Shri Rajesh Upadhyay and Secretary APG Shri Bhupendra Tauk were instrumental in making the event successful. The vote of thanks was proposed by Mr. Sanjay Kumar, Secretary, SPG, Vadodara Chapter.
The Earth Study 360 Imaging System “An Insight into the Interpretation Realm” by Dr.Raanan Dafni, Emerson-Paradigm
Mumbai Chapter of Society of Petroleum Geophysicist (SPG) had organized a technical presentation on, The Earth Study 360 Imaging System “An Insight into the Interpretation Realm” by Dr. Raanan Dafni, Emerson-Paradigm on 7th Nov 2019, at NBP Green Heights, ONGC, BKC, Mumbai. In his interactive and well appreciated presentation, Dr. Raanan highlighted the (a) overview of ES360 Imaging System, (b) benefits of full-azimuth angle-domain imaging, (c) case studies from both Indian and global data and (d) pre-stack interpretative engine, i.e. supplementary information from directional image gathers.

The EarthStudy 360® Imager (ES360 Imager) is a versatile cluster-based depthmigration that simultaneously uses the full recorded wave field within acontrolled aperture to generate amplitude preserved, multi-dimensional, subsurface angle gathers which are 3D full azimuth, directional and reflection angle gathers. The Imager provides fast, target-oriented solutions for local analysis, and can also be used for imaging ona regional scale.It supports isotropic and anisotropic models, and all types of land and marine datasets, including narrow and wide azimuth streamer acquisitions and OBC data. Recently, ES360 migration included converted rays (P to S) also.

Unlike conventional ray-based imaging methods (e.g. Kirchhoff migration), EarthStudy 360 uses a point-diffractor operator to shoot rays from subsurface grid points up towards the surface, forming an accurate system for mapping the recorded surface seismic data into the subsurface Local Angle Domain (LAD) at each image point. This procedure ensures maximum illumination of the image points from all subsurface directions and surface source-receiver locations; all arrivals are taken into account and amplitudes and phases are preserved.

Earth Study 360 directional angle gathers enable specular and diffractionimaging, resulting in simultaneous emphasis on continuous structural surfacesand discontinuous objects such as faults or small-scale fractures, karst features. Structuralattributes at each subsurface image point (e.g. dip, azimuth and specularity)can be derived directly from the directional angle gathers.The ES360 directional angle gathers from Narrow azimuth surveys are suitable for diffraction imaging of discontinuities like faults and fractures as they are directly related to migration aperture and not sensitive to acquisition geometry unlike the reflection angle gathers. The diffraction imaging results are a better way of delineating the discontinuities than traditional ways like coherence cube.


Earth Study 360 reflection angle gathers display reflectivity as a function ofopening angle and opening azimuth and are most meaningful in the vicinity ofactual local reflecting surfaces, where the reflection angles are measured withrespect to the derived background specular direction. They are used forautomatic picking of full-azimuth, angle domain residual moveouts, which together with the derived background orientations of the subsurfacereflection horizons, provide a complete set of data for anisotropic velocity modeldetermination, azimuthally-dependent analysis of residual velocity (VVAZ) or amplitude versus angle/azimuth (AVAZ), using full azimuth angle domain seismic data, in order to determine fractureintensity (strength) and orientation (direction). These fractures derived from the seismic were verified with production data, FMI logs and available micro-seismics.

Regarding the future roadmap of ES360,Dr. Raanan demonstrated the applicability of Deep Learning (DL) to automatically obtaining different types of high resolution subsurface geometrical objects. The Deep Learning method is applied to spatial windows of overlapping full-azimuth directional image gathers. The application of Principle Component Analysis (PCA) on covariance matrices applied to these data windows significantly reduces the data, where only the principle (informative) directivity components are considered. The back propagation of these classified principle components to the image domain shows clear differentiation between structural reflectors, faults and point diffractors, even in areas heavily masked by ambient and coherent noise such as acquisition footprints. This approach shows great promise in identifying subsurface structural features with high accuracy which would be highly beneficial to the interpreters.

Mr. SK Sharma, (GGM-GP), HGS-Mumbai felicitated Dr. Raanan for his fantastic presentation. Mr. CPS Rana, (GGM-GP), Vice-President, SPG, Mumbai Chapter sum up the whole presentation, mentioning the international recognition of activities of SPIC, WOB on ES360 imaging system. Enthusiastic interpreters had made a valuable interaction with Dr. Raanan about the pre-stack interpretative engine of ES360.
SPG Mumbai organised a technical session titled “Imaging and Reservoir Technology Update”on 11th October 2019 at Auditorium, NBP Green Heights, Mumbai.The session is a part of continuous and relentless efforts by SPG to share ideas and experiences to the geo-scientific community and to express & exchange views & opinions on various exploration problems in Mumbai offshore areas. The session was chaired by SPG Mumbai Chapter President Shri K V Krishnan. APG Mumbai Chapter Vice President Shri K. Vasudevan, SPG Mumbai Chapter Office bearers, Geoscientists from different G&G Companies and Students from Colleges were also present.


SPG Mumbai Chapter, President, Shri K V Krishnan emphasised the need of goodseismic imaging in exploration. He also made a point that with the advent of new technology and algorithm advancement, we should focus on robust processing sequence to bring out the difficult Mesozoic gas of Kutch Offshore.

SPG Mumbai Chapter,Secretary, Shri Anupam Sharma briefed on the 13th Biennial International Conference & Exposition scheduled to be held at Lulu Bolgatty International Convention Centre (LBICC), Kochi, Kerala, India from 23rd to 25th February 2020.

APG Mumbai Chapter Vice President Shri K. Vasudevan elaborated the exploration challenges in Western Offshore. He also said that successes in Mesozoic sandstone and Fractured /Weathered Dolerite (Intrusive) of Kutch Offshore need to be studied in detailed. The impact of processing,better imaging and reservoir technology advancement will certainly help in better understanding of these type of reservoirs.
- Processing-Imaging Technology Update- By QING XU Joint 3D Source Deghost and Designature,OBN Deblending, Demultiple,IMA,ISS, FWI, Least Square Q Migration. Processing methodology was detailed with recent advancements and with case studies.
- Reservoir Consulting Services- By ROBERT PORJESZ Introduction to reservoir modelling, 3D/Multicomponent/ 4D Inversion. Main focus of the talk was static model update using sesimc inversion results and computer assisted history matching-update of seismic derived model to match production data.
- G&G Studies (Robertson UK)- By MARK COWGILL Integrated G&G Studies from Exploration to Development & Production, Unconventional Experience and Workflows and Geotraining. The presentation highlighted the approach to digitisation and digitalisation of existing data sets, play fairway mapping, improved seismic imaging and reservoir characterization.

Qing Xu is currently the VP Geoscience, Asia Pacific, Robert Porjesz , Regional Manager, Asia Pacific and Mark Cowgill, Business Development Manager for CGG Geoscience.

SPG Mumbai Chapter, Vice President Shri C P S Rana concluded the technical session with vote of thanks.He said that focus to imbibe recent advancements in processing and world analogue vis a vis Western Offshore Basin, India should be our focus area to work upon.

Society of Petroleum Geophysicists – India, Jorhat Chapter organized a lecture on 25.07.2019 at ONGC, Jorhat on “Emerging Geophysical Technologies for Hydrocarbon Prospecting.” The talk was delivered by Shri U. S. D. Pandey ex-Executive Director of ONGC and attended by over sixty-five G & G professionals and SPG members from ONGC Jorhat.
Session started with welcome address and brief introduction about the objective of the program by President SPG India, Jorhat chapter Shri Vishal Shastri, GGM (GP). He said that such interactive sessions are noble initiatives and give an opportunity, especially to young executives, for Knowledge Sharing. He also detailed future programmes planned under the aegis of SPG-India, Jorhat Chapter that included more lectures and Geophysical & Geological field trips. Shri USD Pandey delivered his talk about ‘Emerging Geophysical Technologies for Hydrocarbon Prospecting’. The participative interaction by the house made the talk fruitful and interesting.




Glimpses of the Programme
Shri Vijay Kumar Gokhale, CGM (Production), Asset Manager gave concluding remarks and emphasised the need of induction of new technologies to arrest the declining production and finding of new oil for sustenance of the production. The meeting concluded with vote of thanks by Shri H N Garg, Vice president, SPG-India, Jorhat chapter.
SPG Ahmedabad Chapter organized a technical lecture on
“Basins, Their Structural Style and Play Fairways”
SPG-Ahmedabad Chapter organized a technical lecture on July 23rd 2019 on the topic “Basins, Their Structural Style and Play Fairways”. The lecture was delivered byProf.Jokhan Ram,former ED-Chief KDMIPE, ONGC and presently occupying the K.D Malviya Chair at Banaras HinduUniversity.
At the start, SPG Ahmedabad Chapter welcomed the distinguished speaker. The scholarly lecture dwelt at length the finer aspects of the subject on structure and tectonics, depositional systems, basin analysis and prospect evaluation.


The speaker covered all the aspects right from formation of different types of basins, various structural styles and its interpretation making use of the geological and geophysical data with example from Indian as well as Basins from across the globe. In the end play fairways were discussed with example form various fields. The event wasattended by large number of SPG members.It was a lively interactive session and was very well received by the audience.


SPG Ahmedabad chapter took pride in conducting such lecture series at regular intervals and looks forward for many more such knowledge sharing events in future.
On April 4th, 2019, the SPG Hyderabad chapter along with NGRI-SEG Student chapter organized a distinguished lecture at SB Hall, CSIR-NGRI, Hyderabad. Prof. Hermann J. Felix delivered SEG Distinguished lecture on “Sometimes it pays to be cheap – Comprehensive time-lapse seismic data acquisition”. Prof. Hermann J. Felix graduated from Delft University in 1992 and received a Ph.D. in Engineering Physics from the same university. His area of expertise is computational exploration seismology including economic and low-environmental impact (time-Lapse) acquisition with compressive sensing, data processing, and wave equation-based imaging and inversion. He developed curvelet-based denoising and match filtering, and also made several contributions to full-waveform inversion and RTM. Recently, he has been involved in developing the rank minimization technique for seismic data acquisition.
The conventional method of acquiring Seismic data requires firing seismic sources at regular intervals of time and record the pressure wavefield reflected from each interface in the earth’s subsurface with the help of receivers or sensors. Seismic surveys can either be performed at land or in a marine environment. The data recorded in the form of seismic traces, which represents the response of elastic wavefield to velocity and density contrast across the interface separating two layers as energy from the source travels to the interface and gets reflected back to the surface to be recorded by the sensors (Geophone/Hydrophones).
To obtain a highly resolved image of the subsurface, conventional imaging algorithms such as RTM requires regularly and densely sampled shots/receivers from seismic surveys. The cost of acquiring densely sampled surveys is insanely expensive, and when time-lapse is of interest, this cost increases too. To resolve the high cost of seismic Surveys, Prof. Felix and his team have developed an idea from Compressive sensing to design surveys that sample data at a cost significantly lower than conventional approaches. Compressive sensing (CS) is a new sampling paradigm that can reduce the cost of seismic surveys. This method uses the seismic source to be fired at random time-jittered compressed-in-time firing times, which is an example of simultaneous source acquisition. In this time-jittered method (in the marine environment), a single source vessel is constantly firing airguns arrays at jittered source locations and time instances with receivers recording continuously. This compresses the survey time and recovers a dense data onto a fine periodic grid with increased source sampling. This sampling method generates surveys with overlapping shot records and coarse source sampling that are subsequently separated and interpolated to finely sampled grid yielding sequentially sampled shots with improvements in spatial sampling.
To accurately recover signals acquired using Compressive sensing, the sampling matrix needs to be accurate, which implies having precise information about the acquisition geometry. In time jittered acquisition, source vessels map the survey area by firing shots at jittered time-instances, which translate to jittered shot locations for a given speed of the source vessel. Since the data acquired is sparse, it is reconstructed and recovered using the sparsity-promoting method and rank minimization technique. Sparsity- and rank-minimization have had a significant impact in many areas over the last several decades. Sparsity in certain transform domains has been exploited to solve underdetermined linear systems with applications to compressed sensing natural image denoising/inpainting, and seismic image processing, along with many other applications, including control, system identification, signal processing, and combinatorial optimization, and seismic data interpolation and denoising.
The talk was open to all the scientists and students of CSIR-NGRI and Osmania University. During the talk, the attendees asked questions, shared opinions, and especially the students were highly enthusiastic in asking questions. Next day a discussion session of two hours was held with students fo CSIR-NGRI and AcSIR. During the discussion, many students showed their work and got their doubts cleared. They also got the new insight which they can use in their research work. Prof. Felix was impressed and happy to see the kind of work students do at CSIR-NGRI. He appreciated the infrastructure and the facilities provided by the Director and the scientists to the students. He also appreciated the warm gesture he received at CSIR-NGRI.

A group photo of SPG Hyderabad chapter and SEG student chapter office bearers with Prof. Felix J. Hermann (center).
SPG, Ahmedabad Chapter Organizes Lectures on
‘A feasibility study on Low Frequency Passive Seismic Survey at the Mansa and Jotana in Cambay Basin and Ashokenagar in MBA Basin’
And
‘Magnetotelluric study to characterize sediment thickness (including Mesozoic) and major faults in Kachchh (Gujarat)’
Society of Petroleum geophysicists, Ahmedabad Chapter,organized special lectures on ‘A feasibility study on Low Frequency Passive Seismic Survey at the Mansa and Jotana in Cambay Basin and Ashokenagar in MBA Basin’ by Dr. A. P. Singh, Scientist-Bfollowed by ‘Magnetotelluric study to characterize sediment thickness (including Mesozoic) and major faults in Kutch (Gujarat)’ by Dr. Kapil Mohan, Scientist-C, of Institute of Seismological Research Department of Science and Technology(ISR), on 22nd January, 2019 at Gandhinagar.Talk was graced by Dr. Sumer Chopra,Director/Scientist-Gand Dr. M. Ravi KumarDirector General, ISR.
In last several years there is an increasing interest in phenomenon of low frequency (0.5-10Hz) anomalies over hydrocarbon reservoirs. Passive Seismic Method is a geophysical method that utilizes a spectral frequency from seismic data to identify a subsurface fluid behaviour / direct hydrocarbon indicator. In thefirst talk the preliminary results of the Low Frequency Passive Seismic surveys (LFPS), which were performed in Ashokenagar#1, Jotana area and Jaguli#1 area were shown. Cityshark 24-bits recorder coupled with a Lennartz LE3d (5s) velocity sensor and Tromino 3G (10s) instruments were used for Jotana, Mansa and Ashokenagar#1,Jaguli#1 fields respectively. The results shows very distinctive V/H ratio >1.5 for Ashokenagar#1 (oil/Gas well) as compared to low value at Jaguli#1 (Dry well). Higher V/H ratios are also observed near proposed location. LFPS survey in 3D grid pattern around proposed locations may be planned for optimal positioning of location. The doublet response instead of single peak as observed in V/H ratio plots need to be critically analysed to ascertain their sources. It may lead to some additional potential zones.


In the second talkit was mentioned that Sediment thickness mapping (including Mesozoics), Delineation of Fault lines (hidden also), Deep Crustal studies and geothermal source zone mapping can be done using Magnetotellurics. Estimation of Mesozoic Sediment Thickness in Kachchh - The total area of the basin is about 71,000 sq km of which on-land area is 43,000 sq km and off shore area is 28,000 sq km up to 200m bathymetry. The basins filled up with 1550–2500m of Mesozoic sediments and 550m of Tertiary sediments in on land region and up-to 4500mof Tertiarysediments in offshore region.
Mesozoic rocks are exposed in six regions viz. Kutch Mainland, Wagad Highland, islands of Pachham, Khadir, and Bela, and in Chorar Hills.Surveyed petroleum source rock distribution in different geological time-scale suggested that more than 50% of source rocks as well as reservoir rock are found in Mesozoic sediments.


Seismological laboratory visit and live data demonstration of earthquake monitoring/ seismograms was also a new experience for all participants.

The session was very informative, interactive and suggestions were taken from the participants for more such talks to be arranged in future.The meeting concluded with vote of thanks and memento to Dr. A. P. Singh, Dr. Kapil Mohan, Dr. Sumer Chopra and Dr. M. Ravi Kumar.
Society of Petroleum Geophysicist (SPG), India, along with SEG (Society of Exploration Geophysicists, USA) and EAGE (European Association of Geoscientists & Engineers), in a first-of-its-kind collaborative initiative, organised two joint workshops on Imaging Challenges in sub-basalt and foothills, at Dehradun on Feb. 22-23, 2019. The two day event held at the Technical Interaction Center (TIC) of GEOPIC saw a total of around 165 delegates, 37 invited speakers and 30 invitees from major NOCs like ONGC, OVL, OIL, BPRL, GAIL etc. and petroleum companies from abroad, like Ecopetrol, Shell, Schlumberger, Shearwater, UK, BGP International, Volcanic Basin Petroleum Research, Oslo, V&G Exploration etc. The academia was well represented by participants from premium research Institutes in India like IIT Mumbai, IIT Kanpur, Wadia Institute of Himalayan Geology (WIHG) etc. as well as from abroad (IPGP, France, University of Grenoble Alpes).
Director (E), ONGC & Patron – SPG, India Mr A.K. Dwivedi was the Chief Guest in the Inaugural Session for the first workshop, “Sub-basalt Exploration in Asia and Pacific”, which was also graced byDr. Kalachand Sain, Director- Wadia Institute of Himalayan Geology (WIHG), Dr Nancy Jo House, former President SEG, USA and Dr Gladys Ethel Gonzalez, former President EAGE and Mr D. Purkayastha, ED-Head - EXCOM, ONGC and President SPG India. In his welcome address, Mr D. Purkayastha welcomed the guests, delegates and speakers and spoke about the relevance of the topics of the workshop particularly in the context of ‘difficult oil’. He also described the background as to how the workshops were conceived and the efforts that went behind in bringing them to fruition. Dr Nancy Jo House and Dr Gladys Ethel Gonzalez, spoke about their optimism that the workshops would live up to the expectations as envisioned and expressed their elation in endeavouring to collaborate with SPG, India for the same. Dr Kalachand Sain, hoped that the workshops would have significant takeaways for the participants.

Director (E)-ONGC Mr. A.K. Dwivedi inaugurating the first day workshop

Director (E)-ONGC delivering his inaugural address

Director (E)-ONGC and other dignitaries inaugurating the workshop proceedings
In his inaugural address, Mr. A.K. Dwivedi, emphasised how workshops such as these could be great opportunities for the geoscientific community to seek answers to many of the challenges that beset them and thanked SEG & EAGE for joining hands with SPG for the current endeavour. He also stressed that while only 7 of the 26 sedimentary basins are established as hydrocarbon bearing, lack of actual understanding of the remaining basins may be largely responsible for success being elusive elsewhere, rather than the absence of petroleum systems there. He stated that role of seismic imaging would be of central to exploration efforts in frontier areas, going forward.
Thirteen technical papers (including six keynotes) and six posters were presented in the first day’s workshop. Diverse topics were covered for sub-Basalt imaging like advanced seismic acquisition parameters designing (Wide Tow acquisition method, long offset, wide azimuth etc.); state of art processing techniques (like Tau-P domain processing, Non-Stretch mute technique, FWI etc.); Full waveform Tomography of wide angle data; Broadband processing and PSDM; Multi Physics Approach (Magnetotelluric method, CSEM, EM etc.) and so on. Different imaging challenges from various Indian basins (like Cambay, Kutch-Saurashrta, Kerala-Konkan basin) and foreign basins (like Rockall Basin, Ireland, Exmouth Plateau, UK Atlantic Margin) were discussed and possible solutions deliberated.
Director (E&D), Oil India Ltd., Dr P. Chandrasekaran inaugurated the second workshop, titled “Current Practice and Advances in Foothills imaging”, held on Feb. 23, 2019. Also present on the occasion were Dr Kalachand Sain, Director WIHG, Dr Nancy Jo House & Dr Gladys Ethel Gonzalez, esteemed representatives from SEG & EAGE respectively, besides Mr D. Purkayastha, President SPG India. In his inaugural speech, Dr P. Chandrasekaran emphasised on the importance of minimising uncertainties and risks as exploration shifts towards more and more difficult geographies and complex sub-surface geologies. He felt that the exploration community relies on seismic processing, perhaps more than any other single link in the exploration chain, to reduce those risks.

Mr D. Purkayastha, President SPG, India welcoming Director (E&D), Oil India Ltd., Dr P. Chandrasekaran (right);

Dr Nancy Jo House, Former President SEG presenting her keynote speech
Ten technical papers and three posters were presented in the second day workshop. Various issues were covered for Thrust Fold Belt imaging like advanced seismic acquisition parameters designing (Wide azimuth acquisition long offset, sparse spread, Single sensor acquisition etc.); state of art processing techniques (Common Reflection Surface processing (CRS), 3D Elastic FWI, Optimum datum processing, anisotropic processing etc.); integration of active and passive seismic data for robust velocity model building and so on. Various imaging issues from several Indian basins (Himalayan foreland basins, Cachar fold Belt, Asam-Arakan Basin etc.) and foreign basins (like Western Qaidam Basin, China, Foothills of Colombia, Western Papuan Fold Belt etc.) were deliberated upon.

Participants interacting in the poster session

Prof. Satish C Singh and Mr Chirag Tyagi summing up the workshop
The deliberations at the workshops were aptly and succinctly summed up by Dr Nancy Jo House (SEG), Dr Gladys Ethel Gonzalez (EAGE), Prof. Satish C Singh (IPGP, France) and Mr Chirag Tyagi (Schlumberger).
Another highlight of the Joint Workshop was a field trip for the foreign delegates to familiarise them of structural and tectonic elements of Frontal Himalayan Fold-Thrust belt in the Dehradun-Mussoorie area, which generated a lot of interest.

Faculty Dr Mohit Punia (Survey of India) showing Himalayan geological structure to the field participants (right).
SPG Mumbai Chapter organized a presentation on “State of the Art software solutions for E&P Challenges, Lithology classification & Stochastic Inversionon 19.01.2018 at ONGC, Priyadarshani, Mumbai.
On behalf of SPG Mumbai Chapter, Shri Anupam Sharma, Secretary SPG, introduced the presenter, Shri C M Jain, Vice President, welcomed the speaker.
Shri Hemant KumarDixit, from M/s CGG GeoSoftwarepresented the solution to quantitatively integrate various data typerelated to geophysics, geology, petro-physics, rock physics and generate realistic 3D numerical models of reservoir properties for flow simulation and production assessment.

Geostatistics provides a powerful framework for combining sparsely sampled high resolution well information with densely sampled but less vertical resolution 3-D seismic information. Thereby accurate estimates of reservoir properties and an assessment of the uncertainty and risks associated with reservoir models. He dealt upon one of the emerging geophysical technology, the stochastic inversion for the prediction of rock and fluid properties. The probabilistic inverse method.

The integration of stochastic inverse methods and geophysical modeling allows generating multiple reservoir models of rock and fluid properties that honour both



Seismic and wells geophysical measurements. Stochastic approach allows sampling multiple solutions from the posterior distribution of model parameters predictions. Stochastic inversion algorithms can be applied to seismic inversions problems as well as petro-physical inversion problems.

Mr Dixit presented detailed feature of LithoSI and GeoSI software modules and demonstrated improvement through few case studies.

More than sixty geoscientist attended the presentation.Shri U S D Pandey, President SPG Mumbai Chapter and Shri M Ayyadurai, ED-Basin Manager, WOB, ONGC presented and a memento to speaker. Vote of thanks was given by Mr. Anupam Sharma, Secretary, SPG- Mumbai Chapter
About speaker : Mr. HemantDixit did his post graduation with M.Tech. in Exploration Geophysics (Applied Geophysics) from the Indian Institute of Technology, Roorkee, India. He has more than fifteen years of experience working as an Interpretation and QI Geophysicist.His core expertise lies in the integration of Seismic Petro physics and Rock Physics, together with application of inversion technology for reservoir evaluation and assessment.He has served as a member in technical committee of SPG India and editorial team member of GeoHorizon magazine published by SPG-India.
Email : hemant.kumar-dixit@cgg.com
Mobile : 9930916244
SSPG, Mumbai chapterorganised a technical session. After the welcome address and brief introduction an ex-ONGCianMr S P Singh,President Global Geoscience Services in Emerson-Paradigm started presentation on “Orthorhombic Earth Modelling and Imaging the Need”on 7th Feb, 2018 at ONGC Panvel.

Mr. Singh talked about accounting anisotropy in data processing is now recognized as an important step in improving the quality of seismic data. In isotropic seismic data processing we consider a single velocity at a depth point and try to flat the gather to the maximum offset to depth ratio. But in reality the model is anisotropic, means we have different velocities at a depth point for different directions. When we try to fit this model with a single velocity, it generates well mis-tie as well as lateral mis- positioning in the migrated image. The anisotropy solution was first successfully tested in ONGC by speaker himself.

Commonly, two forms of anisotropy are considered. The first and most common is vertical transverse isotropy (VTI), or the closely associated tilted transverse isotropy (TTI). This anisotropy is often caused by fine layering of sediments, with the layering smaller in scale than the seismic wavelength. In the case of VTI the bedding planes are horizontal, while in TTI they are dipping.
The second form of anisotropy considered in P-wave processing is horizontal transverse isotropy (HTI). The most commonly considered mechanism for this type of anisotropy is vertical aligned fractures embedded in an isotropic background medium. In reality, the subsurface is likely to contain both types of anisotropy, either combined or in separate layers. An earth model with vertical aligned fractures embedded in a finely layered background is termed as orthorhombic earth model.

These type of anisotropy causes azimuthal travel-time variations which can become apparent at near-tomid-offsets (offset-to-depth ratios of 0.5 and beyond). Study of azimuthal travel-time variations is important for delineation of fracture orientations.
Mr S. P. Singh introduced the concepts of ES360 imaging of M/S. Emerson-Paradigm. He also introduced the concept of anisotropy and its need. He has explained how ES 360 Reflection gather preserves the azimuthal information which is helpful in inversion of the elastic modulus parameters needed for Orthorhombic Earth Modelling.
This knowledge sharing platform was also shared by some representatives of Regional Laboratories, Logging services, Panvel and a few superannuated ONGC personals.
This technical session was attended by more than 60 geoscientists. It was a very interactive presentation. There was a good strength of young executives amongst the audience who took keen interest and participated in interaction. The presentation concluded with a very informative question answer session.
This technical session is also attended by Shri U.S.D. Pandey, ED-CGS- President, Mumbai Chapter, Shri K. V. Krishnan, GGM-HGS and Shri C.P.S. Rana, GM-I/C SPIC

This technical session concluded with felicitation of the speaker and vote of thanks.
About speaker : Mr Shiv Pujan Singh is Director Global Technology of geophysicalservices at Paradigm Houston. His maininterests aremodelling anisotropic velocity, including HTI/orthorhombicanisotropy for identifyingfractures using P-wave seismic data andfull-azimuth image gathers, and AVA(Z)inversion for fracture mapping usingfull-azimuth gathers. He has more than 32 years of experience in the field of data processing.
Email : spsingh@paradigmgeo.com
SPG Mumbai Chapter organized a one day workshop on “Conventional cores and their application in hydrocarbon exploration and exploitation” at Regional Geoscience Lab, ONGC, Panvel on 24.05.2018 attended by participants from ONGC, BPRL, WesternGeco/Schlumberger.

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Secretary, SPG Mumbai Chapter Shri Anupam Sharma welcomed the dignitaries Shri USD Pandey, Shri M. Ayyadurai, Dr Alok Dave, Ashwani Mishra and participants from ONGC, BPRL, WesternGeco and Schlumberger. President SPG Mumbai Chapter & ED-Chief Geophysical Services, Shri U S D Pandey in his inaugural address thanked Basin Manager for providing infrastructure to conduct this workshop at RGL, Panvel and also to Dr Alok Dave for his wholehearted support and cooperation in conducting this workshop.He stressed on the role of core studies in petroleum exploration in general and reservoir characterization throughseismic attributes in particular. He called upon the SPG Office bearer to organize more workshops. ED-Basin manager, WOB Shri M. Ayyadurai exhorted all the participants to fully utilize this golden opportunity to learn fine nuances of core usage analysis from Dr Alok Dave a veteran and teacher par excellence.

Dr. Alok Dave interacting with the participants

Dr Alok Dave gave a brief outline of the workshop with main focus from core to log to seismic and live interaction with rocks i.e., cores from all stratigraphic levels from basement to middle Miocene including all geological aspects relevant to exploration and exploitation. Dr Dave emphasized about the importance of coring to reduce uncertainty in reservoir evaluation by providing data representative of the reservoir at in-situ conditions. He asked all the participants to maximize advantage of this workshop by fully integrating Core studies with Geophysics, Petrophysics, Geochemistry and Reservoir Engineering.

Core samples from various formations
The day was spent in core library where all the participants had firsthand information with cores. Twelve cores were laid out from various wells of western offshore to provide insight on various sub-surface environment starting from Basement complex (for variation in Basement lithologies) to Basal clastics(for facies and environment study) to Basalt (For fractures & integration with FMI) to Panna (Paleocene Early Eocene) (For Sedimentary features and depositional environment) to Jakhau (Early Eocene) (for barrier bar complex) to Jakhau(Early Eocene) (for depositional environment, depth correction by core gamma log) to Bassein(Middle Eocene) for (for Karst and Collapse features) to Middle Eocene Early Oligocene hiatus (for Lst/LstUnconformity) to Daman (Late Oligocene) (for Forced regression) to Early Miocene & Bombay (Early Miocene) (for High resolution T/R cycles in Carbonates) to Middle Miocene (For deep water contourites).


During the concluding session Shri Rana, Head-SPIC, GPS thanked Dr Dave and team for this wonderful workshop and enlightened the house. Secretary, SPG Mumbai chapter Shri Anupam Sharma gave takeaways of workshop and thanked everyone who have contributed for the success of the workshop. In the end Shri R D Chowdhary proposed vote of thanks to one and all.
The title of the talk was “Geomechanical Modelling – Data to Solutions (Nearby Wellbore & Field-Scale)”. It was given by Somesh Bahuguna, Drilling and Geomechanics Team Leader from Schlumberger to an audience of Geoscience personnel of varied seniority and expertise. The talk was attended by Sri Debashish Basu Asset Manager, Ahmedabad Asset and Sri O.N.Gyani Head of Institute, IRS.
The presentation started by a discussion on what is geomechanics and what kind of challenges does it addresses to within the Oil and Gas Industry. It was followed a small recapitulation of basics rock mechanics and intrinsic properties like Poisson’s ratio, Young’s Modulus and extrinsic properties like Horizontal stresses, Overburden stress etc.


In order to provide geomechanics based solution, a Mechanical Earth Model (MEM) is a basic requirement. Hence, presentation described what a 1D is and 3D MEM and what are its various components. What log measurements are required to generate each MEM component was also discussed.
Further part of the presentation was divided into two parts 1D Solution and 3D solutions and relevant case studies. Under both the headings solutions like Drilling solutions using Pore pressure and Wellbore stability modelling, Sanding Analysis, Critical Stressed Fracture analysis for Basement reservoirs, Hydraulic Fracture optimization in tight reservoirs. Of these topics, Hydraulic Fracture optimization was discussed in detail. Importance of Isotropic Stress Model and TIV Anisotropic stress model with regards to laminated reservoirs was discussed.
It was shown how the latter allows for generation of more realistic simulation using stress models which allows proper fracturing job and ideal placement of proppants.


The 3D phase of the presentation started with basic requirements of 3D MEM construction. Concept of coupling of stress model and dynamic pressure model was also discussed. Examples of how coupling allows for estimation of reservoir compaction and surface subsidence were presented along with some case studies. In this context, effect of depletion on reservoir permeability was also discussed along with some case studies. Hydraulic Fracture optimization using 3D numerical modelling was also discussed in detail. Importance of software packages which allow for generation and seamless integration of Static modelling, Stress modelling, Dynamicmodelling and Hydraulic fracture stimulation using numerical algorithms was also discussed.
The talk ended with a Q&A session where audience took active part in the discussion and brought forward their challenges and their experience in dealing with it.
Association of Petroleum Geologists (APG) and Society of Petroleum Geophysicists (SPG), Kolkata Chapter jointly conducted a technical session on 19 March 2018 with the theme “Major Gondwana Basins of India- Problems and Prejudices”. This technical session was attended by all the APG and SPG members of Kolkata Chapter and distinguished retired dignitaries.
Recently the focus of exploration is emphasizing the search for Coal Bed Methane (CBM) and Shale Gas in the Gondwana sequences of the Sedimentary basins of India in addition to exploration of Conventional Hydrocarbon. Hence the technical session was organised to address the various issues related to the exploration of Conventional hydrocarbon, Coal Bed Methane and Shale Gas in Indian sedimentary basins. The lecture was delivered Prof. Dhurjati Prasad Sengupta, Dept. of Geological Sciences, Indian Statistical Institute, Kolkata as an Industry-Academia interaction.

Shri C Mahapatra welcoming Prof. D P Sengupta

ED-Basin Manager and patron APG & SPG Kolkata ChapterProf. D P Sengupta delivering the lecture
Prof. D P Sengupta is an eminent Bio stratigrapher in Dept. of Geological Sciences, Indian Statistical Institute,Kolkata. He has rich experience in the domain of Biostratigraphy of Lower and Upper Gondwana sequences of Indian Basins. He has been working on Gondwana stratigraphy and vertebrate palaeontology with interests inmorphometrics and shape analysis of fossil vertebrates. He has carried out extensive research work; mainly field based on Gondwanas of India and abroad and has erected many new vertebrate taxa and used metamorphic techniques for the first time on Indian Gondwana vertebrate.
The session started with brief presentation about the activities and future plans of APG & SPGKolkata Chapter by Joint Secretary, APG, Kolkata Chapter, Mr G C Deb, DGM (G) and Secretary, SPG, Kolkata Chapter, MrP K Bose, DGM (GP) respectively followed by the lecture & presentation by Prof. D P Sengupta.
The Brief Synopsis of the talk is as follows:
The Gondwana deposits of peninsular India are revisited with the light of new information and ideas. The Gondwana sediments of peninsular India rest on Pre-Cambrian basement and the early Paleozoic deposits are absent in the peninsular part. Some problems and prejudices are inherent to the Indian Gondwanas.
Traditionally, the Gondwana starts with a glacial to fluvio-glacial and glacio-marine Formation called the Talchir. Whether Talchir starts from Carboniferous or Permian-- is the initial question which still remains debatable. The coal regime that followed Talchir is present in all the Permian Gondwana deposits of the southern continents of the world. In fact, the glacial and coaly part with characteristics of Glossopteris-Gangamopteris flora are present in all the Gondwana deposits of India, Australia, Antarctica, South Africa and Argentina.
However, the Triassic ‘Red bed’ that followed Coal-shale-sandstone deposits is not at all restricted in Gondwana. It is a global phenomenon with a global flora and fauna. Continental Triassic sediments, at different parts of peninsular India, differentially fill up the initial rift system that created the Gondwana basins. They also have different fault patterns and sediment loads. Thus, they are not uniform and difficult to correlate among different Gondwana basins of India. On the other hand, overall characteristic lithology (Red Mudstone), flora and particularly, the universal terrestrial fauna make the correlation of Triassic red beds easier in global scale. Thus, during Triassic, Gondwana lost its character as “restricted rift deposits in southern continents”. This creates a problem whether to include Triassic part within Gondwana or not.
In case of the non-marine Jurassic, the story is different for peninsular India. There are very few non-marine Jurassic litho-formations in peninsular India. Most of Indian Jurassics (Peninsular) are marine.
Similarly, in Cretaceous, non-marine sediments of Satpura and that of a small part of Pranhita-Godavari basin, are directly overlying the Gondwanas. Other so called “Cretaceous upper Gondwana” sediments are lying on different basements, but not on Gondwana. They are lithologically different from typical Gondwanas. The flora of Jurassic and Cretaeous, the typical “upper Gondwana flora” is actually a global flora that happened to be present in the “upper Gondwana”.
With all these doubts and indecisive evidences mentioned above, Indian Gondwanas, are still thought to be unified successions with a span of Carboniferous to Cretaceous. However, this concept needs serious rethinking.

President, APG, Kolkata Chapter, Mr. S K Das President, addressing the gathering

SPG, Kolkata Chapter, Mr. S Chakraborty addressing the gathering

APG Jt. Secretary Mr G.C Deb briefing activities of SPG APG, Kolkata Chapter

Secretary Mr P K Bose briefing activities of SPG, Kolkata Chapter
The technical session ended with the concluding remarks of ED-Basin Manager, MBA Basin Kolkataand Patron APG & SPG Kolkata Chapter, Shri ChakradharaMahapatra. He opined that Industry-Academia interaction of such nature is very helpful for ONGC in the long run and more such talks can be organised in future. He urged the participants to discuss and debate ideas, policies& strategies that would allow more comprehensive exploration of the region so as to conclude in a more definitive manner about this region. He also complimented all the SPG and APG members, Kolkata Chapter for organising this technical session.






The session was compered by Ms.Supriya Shukla, Sr. Geophysicist(S), member SPG, Kolkata Chapter and concluded with vote of thanks by Mr.Arun Debasis, Sr. Geologist, member APG, Kolkata Chapter.

Member,SPG Kolkata Chapter, Ms. Supriya Shukla compering the sesion

Member,APG Kolkata Chapter, Mr. Arun Debasis offering vote of thanks

The biennial national level geosciences symposium organized by the Department of Earth Sciences at IIT Bombay ‘Protolith17’saw active participation of students from various Universities/institutes from across the country. The event was conducted as part of outreach activities of the Earth Science Association (ERSA), the umbrella for the local chapters of SEG, SPG, AAPG, SPE and SPLWA. Almost 170 students from 17 Institutes participated in this three-day symposium that included thrilling events, enlightening seminars delivered by stalwarts from industry and academia, and 13 well structured workshops by the faculty of the Department as well as 1 workshop by Schlumberger. Our esteemed sponsors and their generosity and cooperation was instrumental for the execution and success of this symposium. We would extend our heartfelt gratitude to the sponsors ONGC, SPG, IIG and ISR in this regard.
The inaugural ceremony saw the esteemed presence of Shri CM Jain, ONGC. His inaugural speech was not just inspiring for all the budding aspirants present for the symposium but also it was enlightening in terms of the knowledge he imparted to the audience. We were absolutely honoured to have him in our presence.
On the second day, we have another esteemed personality from the oil Industry Shri M Ayyadurai, Executive Director and Basin Manager, Western Offshore, ONGC who delivered a special invited seminar on the Geological history of the western offshore basins. It was very informative and provided the audience an idea about the different exploration datasets and strategies employed for petroleum prospecting. It gave us an idea about the scale of operations that are carried out and the amount of data processing required to gain valuable insights about our natural resources. It was really humbling experience for us to have him amidst us.


On the third-day, we had the SPG-sponsored talk by Sri C V Rao, GM, ONGC and presently the vice-president SPG on the Sub-Basalt Imaging. The talk was very engaging and gave the glimpses of various advanced seismic data acquisition and processing techniques applied for imaging sub basaltic terrains and the interpretations derived from those datasets. Audience got valuable insights about the upcoming and latest technology and the related research behind these developments. It provided us with an idea about the level of research and development employed in the Industry.


SPG IIT Bombay Chapter
ERSA, Department of Earth Sciences
IIT Bombay
Society of Petroleum Geophysicists, Ahmedabad Chapter, Ahmedabad conducted a lecture on “Passive Seismic Tomography (PST), QC and application of PST-derived velocity for seismic imaging” by SEG honorary lecturer Dr. JVSSN Murty at Hotel Metropole on 19th June, 2017.
Session started with brief introduction about the objective of the program by the Secretary SPG, Ahmedabad Chapter ShriHarjinder Singh, DGM (GP). In his welcome address he told that this program was an initiative for Knowledge Sharing and to get better subsurface imaging for Enhanced oil recovery (EOR).Furtherthe talk was targeted to groom the youngsters. He communicated to the house that Dr. Murty developed many software for the benefit of organization. He indicated that DrMurty is contributing a lot to ONGC and Research guide in Gujarat Energy Research and Management Institute (GERMI) even after his superannuation.
President SPG, Ahmedabad Chapter Shri Saroj Kumar Mekap, DGM (GP) welcomed Dr. JVSSNMurty. He recalled his association and appreciated the contribution of Dr JVSSN Murty in the field of Processing and Seismic Software Development for ONGC.
During his lecture Dr. JVSSN Murty,detailed the concept of passive seismic tomography.He explained that Passive Seismic Tomography (PST) method uses both P-wave and S-wave travel times from naturally occurring low-intensity earthquakes recorded over a period of time. Field example was also presented to understand concepts, benefits and the limitations of PST.


In the feedback session it was perceived that the knowledge imparted through presentation and deliberations in the session were of great importance. The participants appreciated the talk and found it very informative.
The meeting concluded with a vote of thanks by Shri Paritosh Chaturvedi, DGM (Geology) Vice-President of SPG Ahmedabad chapter, Ahmedabad.
Society of Petroleum Geophysicist, Duliajan Chapter organized SEG\’s 2017 Honorary Lecturer, South and East Asia by Dr. J. V. S. S. Narayana Murty at Duliajan on 11/05/2017. The topic of lecture was "Passive seismic tomography (PST), QC and application of PST-derived velocity for seismic imaging. Additionally, Dr. Murty delivered a lecture on seismic-imaging on request of the attendees.
Shri B.P. Sharma, Resident Chief Executive, Oil India Limited, Duliajan inaugurated the session and felicitated Dr. Murty. Shri Sharma enlighten the audience with his brief talk on necessity of the technology induction particularly of PST to get better subsurface image and hence reduce exploration uncertainty. Shri G.V.J. Rao, President-SPG Duliajan Chapter welcomed Dr. Murty and talk about that necessity of PST particularly in the geologically complex areas in Upper Assam Basin.


The session was well attended and actively participated by members of SPG-Duliajan Chapter, Geo-scientists of Oil India Limited and Students of Dibrugarh University along with faculty members.
In this lecture, Dr. Murty first detailed the concept of passive seismic tomography and a field example was also presented to understand concepts, benefits and the limitations of PST using natural earthquakes. Various QC measures and conditioning of PST velocity field was discussed with examples to infer better structural information and use PST velocity as an initial model for reprocessing in seismic imaging. During the lecture, detailed parameterization and methodology of tomographic inversion, uncertainties and its limitations in context of hydrocarbon exploration was discussed. During the talk on Seismic-Imaging, principles of various migration algorithms and their applications were discussed. Dr. Murty conveyed thanks to Mrs Peggy Pryor, SEG; Mr G.V.J. Rao, President, SPG Duliajan Chapter & Mr Pawan Kumar Singh, Secretary-SPG Duliajan Chapter for arranging this lecture.


At last Mr D.S. Manral, Chief Geophysicist conveyed vote of thanks with particular mention of Dr. Murty, SPG-India, SEG and Shell for sponsoring the aforesaid programme.
Society of Petroleum Geophysicists, Delhi Chapter organized a Special lecture on “Passive Source 3-D tomography to investigate Crustal and sub-crustal layers of the Earth” by Dr.Om Prakash Mishra of National Centre for Seismology, Ministry of Earth Sciences,Govt. of India , New Delhi on 30.05.2017 at ONGC,PDDU Bhavan,VasantKunj, New Delhi.The lecture covered Passive Source, Geo-tomography ,Deeper Investigations, Material Heterogeneities with Case Studies from India and abroad. The talk suggested to map resolvable seismic tomograms in difficult terrain like Himalayas for identifying deeper potential hydrocarbon reserves using passive source of geotomography. Moreover derivation of Vp,Vs and Vphi, Poission’s Ratio density, porosity and saturation parameters can provide further aids to geoscientific interpretation.
The event was commenced with welcome of Shri.A.K.Dwivedi, Patron SPG India & Director (Exploration),ONGC by Shri.D.Purkayastha, President, SPG India & GGM,ONGC. Shri Surendra Nath Dalei, GM (Geophysics),ONGC,Vice-president & Secretary SPG, Delhi Chapter. Large numbers professionals from geoscience fraternity from different organization like: ONGC, Cairn India, Halliburton and IOCL attended the lecture.
The session was very interactive and suggestions were taken from the participants for such talks to be arranged by SPG, Delhi Chapter, in future.
The event was concluded with the presentation of a memento to Dr.O.P.Mishra by Mr.A.K.Dwivedi.




SEG Honorary Lecture on Passive Seismic Tomography conducted by SPG,NE Chapter Jorhat on 12.05.2017
Society of Petroleum Geophysicists, NE Chapter, Jorhat conducted a lecture on “Passive Seismic Tomography (PST), QC and application of PST-derived velocity for seismic imaging” by SEG honorary lecturer Dr. JVSSN Murty at 1st floor conference hall, LUIT Bhawan, ONGC, Jorhat on 12th May, 2017.
Session started with brief introduction about the objective of the program by President SPG India, NE chapter Shri S K Sharma, GM (GP). In his welcome address he told that this program was an initiative for Knowledge Sharing andwas targeted to groom the youngsters. He welcomed DrJVSSN Murtyto the SPG platform and he recalled and appreciated the contribution of Dr JVSSN Murty in the field of Processing and Mathematical Programming for ONGC.


Shri M Ayyadurai, ED-Basin Manager, A&AA basin, Patron SPG India, NE chapter, in his keynote addressstated that it is a wonderful day for G&G executives especially Geophysicists to hear from one of the domain experts of ONGC. He communicated to the house that Dr Murtydeveloped many software for the benefit of organisation. He indicated that Dr Murty is contributing a lot to ONGC even after his superannuation. He advised the audience to make the lecture more interactive and extract as much as possible information from speaker. He also thanked SPG, NE Chapter for arranging such a nice lecture.
During his lecture Dr. JVSSN Murty, explained that Passive Seismic Tomography (PST) method uses both P-wave and S-wave travel times from naturally occurring low-intensity earthquakes recorded over a period of time. He stated that due to low cost and relative ease in operation, PST has made inroads into hydrocarbon exploration, especially in difficult terrains, by inferring structural and lithological information from the VP and VP/VS volumes as well as incorporating the velocity models in seismic imaging projects in areas of poor quality seismic data where determining the initial velocity is difficult. He specified that the success of PST depends on the natural seismicity in the area and sufficiency of data recorded for estimating depths of the hypocentres and velocity fields using tomographic inversion. He also exhibited the results of PST survey, earlier carried out in Sector VC of Cachar Fold Belt.


In the feedback session it was perceived that the knowledge imparted through presentation and deliberations in the session were of great importance. The participants especially young geoscientists were keen and interactive throughout the program.
At the end, the meeting was concluded with a vote of thanks by Shri Chakradhar Rao Basa, Treasurer of SPG NE Chapter, Jorhat.
Society of Petroleum Geophysicists, NE Chapter,Jorhat conducted a lecture series at LUIT Bhawan conference hall, ONGC, Jorhat on 21st March, 2017.
Session started with brief introduction about the objective of the program by President SPG India, NE chapter Shri S K Sharma, GM (GP). In his brief address he told that this program is an initiative for Knowledge Sharing and targeted to groom the youngsters. He welcomed Shri M Ayyadurai, ED-Basin Manager, Patron SPG NE Chapter and Shri G V Reddy, GM (GP) to the SPG platform. He informed the house about the previous programs conducted by SPG. He also urged the youngsters to come up with new ideas.



Shri M Ayyadurai, in his welcome address advised the youngsters to have multidisciplinary exposure of acquisition, processing and interpretation with a constructive motto. He recalled and appreciated the contribution of Shri G V Reddy towards the exploring and developing of Mekrang and BabejiaFields of South Assam Shelf (SAS).
The first lecture delivered by Shri A K Chakraborty, SG on “Recent discoveries of SAS Block and their exploratory significance”. He explained recent exploration activity in SAS and highlighted the discovery of Dayalpur field. The well DP#1 is producing oil from several sands.
It was followed by another enlightening lecture by a young geoscientist Shri Mahavir Singh, Sr Geophy (S) on “Swath line Geometry: an Innovative Approach”. During his talk he explained about innovative geometries adopted during seismic data acquisition in Fold Belt areas of A&AA Basin. He also shown the results of swath line geometry,well appreciated by the house.



The last lecture of the day delivered by Shri Chakradhar Rao Basa, Sr Geophy (S) on “Advances in Seismic imaging of Fold Belt after reprocessing”.He explained the house about the improved imaging of Fold Belt. He also highlighted the efforts of processing center for bringing out the desirable results after the reprocessing.
Shri G V Reddy, GM (GP) in his feedback cherished the efforts of the geoscientists of A&AA Basin. He especially appreciated the youngsters and also stated that they are very intelligent than the youth of his generation. He thanked ED-Basin Manger and SPG NE Chapter for inviting him for this technical session.



In the feedback session it was perceived that the knowledge imparted through deliberations and presentations in all the three session was of great importance. The participants especially young geoscientists were keen and interactive throughout the program.
At the end, the meeting was concluded with a vote of thanks by Shri M H Sastry, GM (GP), Vice-President of SPG NE Chapter, Jorhat.
Society of Petroleum Geophysicists, Delhi Chapter organized a Special lecture on “Passive Source 3-D tomography to investigate Crustal and sub-crustal layers of the Earth” by Dr.Om Prakash Mishra of National Centre for Seismology, Ministry of Earth Sciences,Govt. of India , New Delhi on 30.05.2017 at ONGC,PDDU Bhavan,VasantKunj, New Delhi.The lecture covered Passive Source, Geo-tomography ,Deeper Investigations, Material Heterogeneities with Case Studies from India and abroad. The talk suggested to map resolvable seismic tomograms in difficult terrain like Himalayas for identifying deeper potential hydrocarbon reserves using passive source of geotomography. Moreover derivation of Vp,Vs and Vphi, Poission’s Ratio density, porosity and saturation parameters can provide further aids to geoscientific interpretation.
The event was commenced with welcome of Shri.A.K.Dwivedi, Patron SPG India & Director (Exploration),ONGC by Shri.D.Purkayastha, President, SPG India & GGM,ONGC. Shri Surendra Nath Dalei, GM (Geophysics),ONGC,Vice-president & Secretary SPG, Delhi Chapter. Large numbers professionals from geoscience fraternity from different organization like: ONGC, Cairn India, Halliburton and IOCL attended the lecture.
The session was very interactive and suggestions were taken from the participants for such talks to be arranged by SPG, Delhi Chapter, in future.
The event was concluded with the presentation of a memento to Dr.O.P.Mishra by Mr.A.K.Dwivedi.




A technical talk was delivered by Mr. R R Tiwari, DGM(Geophysics-Wells), CEWELLS, ONGC, Vadodara on “Geoemchanics:from Exploration to Abandonment” on 5th sept’16.
The talk focused on the importance of Geomechanics in the oil industrybeginning with exploration phase to abandonment. A geomechanical model is required to address the issues of drilling instability, well placement, hydraulic fracturing and sand cut. These models can also be used to forecast events like reservoir compaction, fault slippage or reactivation, cap-rock seal failure and surface subsidence during the production phase of a field.
Oriented Perforations in the direction of maximum horizontal stress are preferred in high stress anisotropy areas so that set of fractures are favourably oriented to fail in shear under present day stress field are said to be critically stressed.These fractures exhibit very good flow characteristics consequently their identification is essential for optimal development.
Mr. Tiwari explained how in a normal faulting region faulting may be induced if stress path becomes more than the critical value due to depletion. Also as fluid pressure is reduced due to production, unconsolidated or poorly consolidated reservoirs may face compaction and even surface subsidence. Shallow reservoirs with large areal extent (low D/R ratio) will exhibit maximum surface subsidence with respect to total reservoir compaction, shallow gas reservoirs being the most vulnerable. Gas bearing Bandra formation may witness such an event. Gas producing fields of KG-DWN-98/2 block may also be prone to deformation, compaction and consequently subsidence as they are shallow and unconsolidated.
Gas producing fields of KG-DWN-98/2 block may also be prone to deformation, compaction and consequently subsidence as they are shallow and unconsolidated.






Mr. Arun Kumar, Patron of SPG-APG, Vadodara chapter emphasized the importance of such technical programs and desired that it shall be held more frequently. President, SPG Mr. S Panigrahi congratulated SPG, Vadodara chapter for doing the good job of educating the geoscientificcommunity through its various programs. Program was ably compared by Mr. K P Singh, Secretary, SPG, Vadodara Chapter.
Team-SPG & APG
Gas producing fields of KG-DWN-98/2 block may also be prone to deformation, compaction and consequently subsidence as they are shallow and unconsolidated.








SPG booth No:323 in GEOINIDIA2015 has attracted audience as it is informative about various SPG activities through posters and AV show in TV screen. Actiivities related to earlier conferences and participation in International events were shown in posters. SPG objectives and information about internal GEOHORIZONS magazine were also displayed.
An MOU for conducting the workshop on full wave seismic is also signed between SPG and EAGE.
Call for papers Special issue on unconventional Exploration in Indian basins and for GEOTECH2015 on Basement exploration attracted many audience to the stall. Many international reputed personalities visited stall and actively participated in the discussion and made enquiries about activities.
Stall attracted young executives and student members and participation is seen throughout the three day show.
Efforts made by our SPG office bearers is also noteworthy


















MOU Signed between SPG and EAGE on 12th Jan 2015 for technical collaboration, details to follow
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