A technical webinar was organized by SPG, India on “Seismic Data Acquisition – Philosophy, use and abuse” on 26th November 2020 by Shri C. V. Rao, Ex-GM, ONGC. The technical webinar highlighted through reviews on the basics of seismic data acquisition and its advancement in past few decades. Shri Rao started his talk with wave propagation principle and the philosophy of seismic data acquisition and ended with discussing recently developed acquisition techniques like High Density Seismic, Node Based Seismic and Wireless Seismic.

He also emphasised on the importance of optimized survey designing on seismic acquisition.

The webinar session was attended by the members of SPG-India from all over the country and other Geoscientists of KDMIPE, GEOPIC, Frontier Basins and professors and students from different Institutes. The lecture was well appreciated by all the participants and praised by one and all for its contents and thoughtful discussion provided by the presenter. During the webinar session participants actively participated on discussion and asked various question related to seismic data acquisition.

Earlier, Shri Shiv Kumar Sharma, President SPG-India gave the welcome speech. The vote of thanks was given by Vice President SPG-India Shri C B Yadava. The entire webinar session was coordinated by Dr. Koushik Biswas, Executive Member, SPG-India.

SPG Ahmedabad chapter organized a trip to Geophysical field party GP-16 camping at Valod area, Gandhinagar on 16th March 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.

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.

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.