Introduction

As an unconventional hydrocarbon resource, methane hydrates have been the focus of our quest for meeting our energy demands and it was this objective that India’s National Gas Hydrate Program(NGHP) was launched.Steered by the ministry of Petroleum & Natural Gas and technically ccoordinated by Directorate General Of Hydrocarbons(DGH), NGHP is a consortium of National E&P companies (Oil and Natural Gas Ltd. ,Gas Authority of India Ltd.) and National Research Institutions(National Institute of Oceanography,National Geophysical Research Institute and National Institute of Ocean Technology).


Commercialization

As per the Road Map linked below the commercial production of methane from gas hydrates is still a far fetched thought although NGHP has set itself a deadline of mid 2015 as the time to commence commercial production, the commercial production of methane from Indian Gas Hydrate resources has its own set of challenges, a few would perhaps be :

• Absence of representative deepwater gas hydrates field anywhere in the world
• Gas production rate ( Gas in the production testing of Mallik well in Canada’s permafrost area have yielded very low production rate and could not sustain more than 7 days of production using thermal and depressurization methods )
• Managing Water production rate ( High amount of water is expected to be produced along with the dissociation of hydrates )
• Sand control since the hydrate reservoirs exist at very shallow depth below sea bed ( 200-400 mbsf) the sands here would not be consolidated due to absence of overburden pressure.
• Reservoir subsidence and other environmental hazards

These challenges can only be overcome by sustained commitment of our scientists and establishment of a proper gas hydrate R&D center in India. The global gas hydrate communities of scientists and researchers have to work in tandem with each other. DGH on behalf of the NGHP has signed Memoranda of Understanding in the field of Gas Hydrates with Japan Oil, Gas, Metal Corporation JOGMEC, Gas Hydrate R&D Organisation ( GHDO ) of the Korea Institute of Geology, Mining and Materials ( KIGAM ) and the US Department of Energy (USDOE) another MOU with the US Geological Survey (USGS) is in the pipeline. DGH has been closely associated with the USGS , USDOE and JOGMEC scientists which has helped the NGHP scientists to gain a lot in terms of knowledge, understanding and experience.

Road Map


R&D Advances in India


DGH has done pioneering work for initiating gas hydrate exploration in the country. Reconnaissance surveys carried out by DGH in the East Coast and Andaman Deepwater areas in 1997 deciphered the most promising areas for Gas Hydrates. The surveys have indicated the presence of several Gas Hydrate leads/ prospects. The total prognosticated gas resource from the gas hydrates in the country is placed at 1894 TCM.

Government of India formulated a National Gas Hydrate Programme (NGHP) in 1997 for exploration and development of gas hydrates resources of the country. The DGH is actively involved in the programme. In fact, the Director General is the coordinator of the Technical Committee of NGHP.

Following reconstitution of the NGHP in the year 2000 by MOP&NG, a new sense of urgency was imparted to the programme and it was put on a fast track implementation.

Introduction
The National Gas Hydrate Program (NGHP) is a consortium of National E&P companies (Oil and Natural Gas Corporation Ltd ‘ONGC’, GAIL India Ltd & Oil India Ltd ‘OIL’) and National Research Institutions (National Institute of Oceanography, National Geophysical Research Institute and National Institute of Ocean Technology). Steered by the Ministry of Petroleum & Natural Gas and technically coordinated by Directorate General of Hydrocarbons (DGH) NGHP is given the responsibility to explore the Gas Hydrates in India.

NGHP during its 1st expedition through a Consortium consisting of Overseas Drilling Ltd (ODL), Fugro McClelland Marine Geosciences, Geotek Ltd, Lamont-Doherthy Earth Observatory (LDEO) and scientists from numerous universities and national laboratories, has struck rich deposits of Massive Gas Hydrates present within the fractured shales in the KG offshore area. United States Geological Survey (USGS) was the main technical collaborator in this expedition.

The Technical Committee of NGHP reviewed the seismic data of the entire continental shelf of India for identifying the best areas for conducting further gas hydrate studies. Two ‘Model Field Laboratory Areas’ one each along the east and west coasts were identified based on the data review carried out by the Technical Committee. More geoscientific data were acquired by National Institute of Oceanography (NIO) in these areas on behalf of NGHP, to look for more proxies for gas hydrates in addition to the seismic signatures. These geoscientific data included i.e., Side Scan Sonar, Swath bathymetry, Chirp Sonar data, water samples and gravity cores for geochemical analysis.

The microbiological studies were also carried out on the gravity cores. All these data and studies revealed several proxies of gas hydrates.

Based on the detailed seismic data interpretation and special processing by DGH through Western Geophysical and Reliance Industries Limited, the Andaman offshore and Mahanadi areas were also added to the other two identified areas for ground truthing through coring/ drilling.

The study enabled NGHP scientists in firming up of locations for drilling and coring of gas hydrate bearing sediments in four areas, i.e. K.G. and Mahanadi Basins in East Coast, Kerala-Konkan basin in the west coast and Andaman offshore.

Expedition Overview
Initial planning called for ten sites to be occupied and twenty seven holes were scheduled for drilling. Of these, eight sites were scheduled for LWD/MWD drilling and two sites were scheduled for coring and wireline logging only.

Expedition NGHP-01 began at 0600 hr 28 April 2006 with the arrival of the drill ship in Mumbai, India, and ended 113.5 days later in Chennai, India with the last line away North Quay at 1912 hr 19 August 2006. Ultimately twenty one sites were occupied with five sites re-occupied at least once. Thirty nine holes were drilled. Of these, twelve holes were LWD/MWD drilled, twenty two holes were cored, and four holes were drilled as dedicated wireline logging holes. Thirteen holes were wireline logged and temperature gradients were established in eleven holes.

During Expedition NGHP-01 there were 494 cores cut with 2847.01 meters of core recovered reflecting 78.7% of the interval cored. A total of 76 in situ temperature measurements were also attempted using three different wireline temperature tools.

For organizational purposes, Expedition NGHP-01 was divided into five operational segments. The first segment, or leg, consisted of a single hole cored and wireline logged in the Konkan-Kerala (KK) Basin off the West coast of India. The second comprised solely of LWD/MWD holes. During leg 2, twelve holes at ten sites were drilled in the Krishna-Godavari (KG) Basin off the west coast of India. Leg 3A consisted of six cored holes and two dedicated wireline logging holes at four sites located in the KG Basin. Two sites were re-occupied sites that were previously LWD/MWD drilled on Leg 2 and two sites were new. Leg 3B consisted of seven cored holes plus one hole that was abandoned due to hole conditions before any coring or logging could be initiated. Five sites were occupied including two that were re-occupied LWD/MWD sites and three that were new additions. All sites were located in the KG Basin. The expedition was completed on Leg 4 with the drilling of two holes (one dedicated to wireline logging) at one site located in the Andaman Sea, three holes at two sites located in the Mahanadi (MN) Basin off North Eastern India, and two holes back in the Krishna-Godavari Basin off the South Eastern coast of India.

Finally more than 2800 m of cores were cut from 21 sites and 39 holes

Results
The NGHP efforts in Indian offshore for gas hydrate exploration led to the following:
• Conducted comprehensive analyses of gas-hydrate-bearing marine sediments in both passive continental margin and marine accretionary wedge settings;
• Discovered gas hydrate in numerous complex geologic settings and collected an unprecedented number of gas hydrate cores (more than 2800 m from 21 sites and 39 holes);
• Delineated and sampled one of the richest marine gas hydrate accumulations yet discovered in the world (Krishna-Godovari basin)
• Discovered one of the thickest and deepest gas hydrate occurrences yet known (Andaman Islands) which revealed gas-hydrate-bearing volcanic ash layers as deep as 600 meters below the seafloor;
• Established the existence of a fully developed gas hydrate system in the Mahanadi basin of the Bay of Bengal;

All the ongoing geoscientific studies of NGHP Expedition 01, 2006 will be completed by January, 2008. NGHP is currently focusing on gas hydrate reservoir delineation and resource estimation in the K. G. area. The identification of the promising sites for NGHP Expedition 02 for riser drilling and pilot production testing will be taken up after completion of the ongoing studies on samples and data from NGHP Expedition 01, 2006. This could even mean acquiring seismic data focusing on shallow depths.

Challenges
There is still no proven technology world over to exploit methane from Gas hydrate on a commercial scale. Moreover since much of the gas hydrate reserves worldwide are found disseminated in sandstone whatever research being done on the extraction of gas from hydrates focus on disseminated deposits in sands. This is in contrast to our discovery of gas hydrates in KG offshore, which are massive in nature and found in fractured shales.

Gas hydrates are unconventional hydrocarbon deposits and much of the work being done world over is in research stage. Therefore an extremely close coordination and work association is requires with leading scientists globally to be updated with the recent developments and device methodologies to incorporate the research to best suit our requirements.


Expedition NGHP01

The National Gas Hydrate Program (NGHP) is a consortium of National E&P companies (Oil and Natural Gas Corporation Ltd ‘ONGC’, GAIL India Ltd & Oil India Ltd ‘OIL’) and National Research Institutions (National Institute of Oceanography, National Geophysical Research Institute and National Institute of Ocean Technology). Steered by the Ministry of Petroleum & Natural Gas and technically coordinated by Directorate General of Hydrocarbons (DGH) NGHP is given the responsibility to explore the Gas Hydrates in India.

NGHP during its 1st expedition through a Consortium consisting of Overseas Drilling Ltd (ODL), Fugro McClelland Marine Geosciences, Geotek Ltd, Lamont-Doherthy Earth Observatory (LDEO) and scientists from numerous universities and national laboratories, has struck rich deposits of Massive Gas Hydrates present within the fractured shales in the KG offshore area. United States Geological Survey (USGS) was the main technical collaborator in this expedition.

Expedition Overview
Initial planning called for ten sites to be occupied and twenty seven holes were scheduled for drilling. Of these, eight sites were scheduled for LWD/MWD drilling and two sites were scheduled for coring and wireline logging only.

Expedition NGHP-01 began at 0600 hr 28 April 2006 with the arrival of the drill ship in Mumbai, India, and ended 113.5 days later in Chennai, India with the last line away North Quay at 1912 hr 19 August 2006. Ultimately twenty one sites were occupied with five sites re-occupied at least once. Thirty nine holes were drilled. Of these, twelve holes were LWD/MWD drilled, twenty two holes were cored, and four holes were drilled as dedicated wireline logging holes. Thirteen holes were wireline logged and temperature gradients were established in eleven holes.

During Expedition NGHP-01 there were 494 cores cut with 2847.01 meters of core recovered reflecting 78.7% of the interval cored. A total of 76 in situ temperature measurements were also attempted using three different wireline temperature tools.

For organizational purposes, Expedition NGHP-01 was divided into five operational segments. The first segment, or leg, consisted of a single hole cored and wireline logged in the Konkan-Kerala (KK) Basin off the West coast of India. The second comprised solely of LWD/MWD holes. During leg 2, twelve holes at ten sites were drilled in the Krishna-Godavari (KG) Basin off the west coast of India. Leg 3A consisted of six cored holes and two dedicated wireline logging holes at four sites located in the KG Basin. Two sites were re-occupied sites that were previously LWD/MWD drilled on Leg 2 and two sites were new. Leg 3B consisted of seven cored holes plus one hole that was abandoned due to hole conditions before any coring or logging could be initiated. Five sites were occupied including two that were re-occupied LWD/MWD sites and three that were new additions. All sites were located in the KG Basin. The expedition was completed on Leg 4 with the drilling of two holes (one dedicated to wireline logging) at one site located in the Andaman Sea, three holes at two sites located in the Mahanadi (MN) Basin off North Eastern India, and two holes back in the Krishna-Godavari Basin off the South Eastern coast of India.

Finally more than 2800 m of cores were cut from 21 sites and 39 holes

Results
The NGHP efforts in Indian offshore for gas hydrate exploration led to the following:
• Conducted comprehensive analyses of gas-hydrate-bearing marine sediments in both passive continental margin and marine accretionary wedge settings;
• Discovered gas hydrate in numerous complex geologic settings and collected an unprecedented number of gas hydrate cores (more than 2800 m from 21 sites and 39 holes);
• Delineated and sampled one of the richest marine gas hydrate accumulations yet discovered in the world (Krishna-Godovari basin)
• Discovered one of the thickest and deepest gas hydrate occurrences yet known (Andaman Islands) which revealed gas-hydrate-bearing volcanic ash layers as deep as 600 meters below the seafloor;
• Established the existence of a fully developed gas hydrate system in the Mahanadi basin of the Bay of Bengal;

All the ongoing geoscientific studies of NGHP Expedition 01, 2006 will be completed by January, 2008. NGHP is currently focusing on gas hydrate reservoir delineation and resource estimation in the K. G. area. The identification of the promising sites for NGHP Expedition 02 for riser drilling and pilot production testing will be taken up after completion of the ongoing studies on samples and data from NGHP Expedition 01, 2006. This could even mean acquiring seismic data focusing on shallow depths.

Challenges
There is still no proven technology world over to exploit methane from Gas hydrate on a commercial scale. Moreover since much of the gas hydrate reserves worldwide are found disseminated in sandstone whatever research being done on the extraction of gas from hydrates focus on disseminated deposits in sands. This is in contrast to our discovery of gas hydrates in KG offshore, which are massive in nature and found in fractured shales.

Gas hydrates are unconventional hydrocarbon deposits and much of the work being done world over is in research stage. Therefore an extremely close coordination and work association is requires with leading scientists globally to be updated with the recent developments and device methodologies to incorporate the research to best suit our requirements.

Strategy
Work association of Indian Scientists with that of US & Japan, the two other countries besides India who have contributed largely in this field, jointly undertaking R&D studies for knowledge sharing and information exchange. This can also include holding of joint seminars and conferences in the area of Gas Hydrate research & development.

Form a tripartite consortium of Hydrate R&D taking US as a consortium partner and take up joint exploration & Exploitation programme in offshore US, Japan & India on cost sharing basis. This would enable worldwide hydrate experts to work jointly on projects and gain expertise & experience which would be useful to all the 3 countries.

Establishing a national Gas hydrate R&D Center / Directorate in India, to look into the exploration & exploitation aspects of Gas Hydrates. This would help extract the best from the intellectual resources present in our country. This is important because even though we carry out activities related to Gas hydrate exploration most of the research work on the samples/ cores/ data obtained from our shores at our cost are sent abroad for further studies and Indian scientists never have the opportunity to have working experience on such studies, even if work association with foreign scientists is carried out, knowledge transfer does not take place on a continuous basis. This may be acceptable on a short term basis but in the long run it is essential that we develop our own intellectual resources and expertise. An exclusive R&D Centre in India is the need of the hour and a step in the right direction. The R&D Directorate may be kept under the aegis of the DGH, with intellectual resources drawn from E&P companies, Research and Academic Institutions within the country who may be permanently posted to this Directorate on non transferable basis. This would further bring all intellectual resources in a specialized field like gas hydrates, which currently are scattered all over the country under one common roof for yielding efficient results.

Preamble :.

Oil Shales are usually fine-grained sedimentary rocks containing relatively large amounts of organic matter from which significant quantities of shale oil and combustible gas can be extracted by destructive distillation. The product thus generated is known as synthetic crude or more simply, syncrude. Included in most definitions of oil shale, either stated or implied, is the potential for the profitable extraction of shale oil and combustible gas or for burning as a fuel. An oil shale, which has a very high proportion of organic matter in relation to mineral matter, is categorized as a coal.

Oil shales range in age from Cambrian to Tertiary and occur in many parts of the world. Deposits range in size from small occurrences of little or no economic value to those of enormous size that occupy thousands of square miles and contain many billion barrels of potentially extractable shale oil. Total world resources of oil shale are conservatively estimated at 2.6 trillion barrels. However, petroleum-based crude oil is cheaper to produce than shale oil because of the additional costs of mining and extracting the energy from oil shale. Because of these higher costs, only a few deposits of oil shale are currently being exploited in China, Brazil, and Estonia. However, with the continuing decline of petroleum supplies, accompanied by increasing costs of petroleum, oil shale presents opportunities for supplying some of the fossil energy needs of the world in the years ahead.

History of the Oil Shale Industry :.

The use of oil shale for extraction of shale oil is more than 200 years old. An oil shale deposit at Autun, France ,was exploited commercially as early as 1839. The Scottish oil shale industry began about 1859, the year that Colonel Drake drilled his pioneer well at Titusville. As many as 20 beds of oil shale were mined at different times. Mining continued during the 1800s and by 1881 oil shale production had reached one million metric tons per year. With the exception of the World War II years, between 1 and 4 million metric tons of oil shale were mined yearly in Scotland from 1881 to 1955 when production began to decline, then ceased in 1962. Canada produced some shale oil from deposits in New Brunswick and Ontario in the mid-1800s. In Sweden, the alum shale was retorted for hydrocarbons on a small scale in the late 1800s. Production continued through World War II but ceased in 1966 because of the availability of cheaper supplies of petroleum crude oil.

With the introduction of the mass production of automobiles and trucks in the early 1900s, the supposed shortage of gasoline encouraged the exploitation of oil shale deposits for transportation fuels in the United States of America. Many companies were formed to develop oil shale deposits of the Green River Formation in western United States, especially in Colorado. The US has an estimated 1.8 trillion barrels of oil trapped in shale, most of it concentrated in the Green River Formation, which covers northwest Colorado and parts o Utah and Wyoming. This estimate is more than all the proven reserves of crude oil in the world today.

In the US, many licenses were issued in the 1970s for exploitation of shale oil. However, after several large-scale mine facilities were developed in the 1970s, the work gradually ceased and the last large-scale mining and retorting facility in western US which was operated by Unocal from 1980, closed down in the year 1991. Unocal produced 4.5 million barrels of oil from oil shale averaging 34 gallons of shale oil per ton of rock over the life of the project.

Processes for Syncrude Production & Environmental issues :.

Various technologies for production of syncrude from coal/oil shale are currently known throughout the world. Most of the commercial processes are based on pyrolysis and/or distillation coal/oil shale in a retort to which heat can be supplied either directly through combustion within the retort or indirectly by performing the combustion outside of the retort and contacting hot gases or solids with coal/oil shale feed. Most modern oil shale technology involves variations of directly heated retorting. Some of the well known indirect processes are Lurgi-Ruhrgas, TOSCOII, Union Oil ‘A’ ad ‘B’, Petrosix, Paraho shale oil etc. All processes use the oil shale itself or its by products as the source of heat.

Retort structures may also be formed underground by a combination of explosive fracturing and mining. This is termed In-Situ Processing. The necessary heat is provided by injecting air or hot gases and steam to sustain movement of the fire front in oil shale formation in either a horizontal or vertically downward mode, causing the shale oil to collect at the bottom of the In-Situ retort, from where it can be pumped to the surface. Geo Kinetics In-Situ and Occidental Modified In-Situ processes are two well known examples.

The processes of syncrude production results in vast quantities of spent shale. These are absolutely barren and cannot support any vegetation and may also retain toxic ingredients. The disposal of spent shale thus poses a serious environmental challenge. However, the In-Situ process has certain advantages in this aspect. For instance, the disposal of solid wastes is taken care of, the environmental degradation such as deforestation is minimized, the hazardous gases emissions into the atmosphere is contained and problems related to waste water disposal containing toxic elements is substantially reduced.

The in-situ conversion process has been adopted by Shell in their Mahogany Project in Colorado for the past several years. This technology employs heating elements to raise rock temperatures to required levels for syncrude production.

During the 3rd meeting of the oil and gas working group in Washington in July, 2006, discussions were held, inter alia, on oil shale with Ms.Brenda Pierce of United States Geological Survey (USGS) and Mr.Ted Murphy, Division Chief, Solid Minerals, Bureau of Land Management (BLM). Both these organizations are under the Dept. of the Interior, United States Government. The discussions centered on the work carried out by USGS and BLM on oil shale and status of oil shale development in USA and regulations regarding leasing of fedral lands for oil shale exploitation. BLM informed that eight (8) leases have been awarded for oil shale RD & D projects to four companies in the states of Colorado, Utah and Wyoming.

DGH has also initiated a dialogue with the Colorado Energy Research Institute (CERI) for interaction on oil shale. CERI, under the Colorado School of Mines is one of the premier institutes engaged in active oil shale research and development. They organize an exclusive oil shale symposium every year that draws specialists from various countries. DGH has also participated and presented technical paper in this symposium.

The Indian Scenario :.

North-East India is endowed with rich deposits of coal. The coal is found in the Barail Formation of Tertiary age. Carbonaceous shale occurs interbedded with the coal. The presence of coal and shale has been recorded in wells drilled for hydrocarbons by ONGC and OIL. These formations outcrop on the surface towards the south of the oil fields in a region called the Belt of Schuppen. Studies have indicated that these coals and carbonaceous shale constitute the principal source rocks that have generated the hydrocarbons produced from the region.

The favourable characteristics of Assam coal for conversion to liquid fuels have been known for a long time. CFRI (Dhanbad) had carried out a feasibility study on this subject and submitted a report as far back as in 1968. Commonly, the assessment of the yield of hydrocarbons from coal or oil shale is based on pyrolysis or heating under controlled conditions. The standard method has been the Fischer Assay, a scaled down retorting process in which the residue and generated by-products viz. hydrocarbons are collected, measured and chemically analyzed. Evaluation of the yield potential can also be determined quantitatively by another pyrolysis technique called Rock-Eval pyrolysis. In this equipment, small quantities of the sample are pyrolyzed under controlled conditions. The amount of hydrocarbons generated and expelled can be volumetrically determined by this method.

In the late 1980s, Oil India Limited and Robertson Research Inc. (UK) had analyzed a large number of rock samples obtained from oil wells, outcrops and coal mines in connection with hydrocarbon exploration in the region. The Rock-Eval yields for the coal and carbonaceous shale indicate prolific hydrocarbon potential for Barail Coals, of the order of 280 kgs of hydrocarbons per ton of rock. The Barail Series oil shale gave a maximum yield of about 80 kg hydrocarbons per ton of rock. This compares favourably with some of the yield values obtained from other oil shale deposits in the world.

In order to assess the viability of syncrude generation from the Assam coal, OIL established a pilot plant for the extraction of oil from the coals of Assam with technology from the USA.

With respect to oil shale, the current position is that the resources are not known with any measure of confidence. Much more ground work needs to be undertaken before the reserves can be established. Once this is done, selection of the appropriate technology can be taken up.

The Directorate General of Hydrocarbons (DGH), under the Ministry of Petroleum and Natural Gas, has embarked on a project for the evaluation of oil shale resources and their syncrude potential in parts of Upper Assam and neighboring area in Arunachal Prdesh. The study which is being carried out by a consortium comprising BRGM, France and MECL, India is expected to provide valuable information on this fossil fuel source. Considering the energy security of our country, the project is of national importance.

The evaluation of oil shale resources involves field work, mapping, and collection of rock samples from surface exposures, drilling of few core holes, preparation of maps and feasibility studies. The study is expected to be completed by October/November, 2009.

Phase-I (Sept.2007 to October 2009)
The contract for the implementation of the oil shale project was signed in September, 2007 between DGH and a consortium comprising BRGM, France and MECL, India. The project envisages assessment of oil shale resources in three discrete adjacent blocks, covering a total area of about 250 sq.km. in the states of Assam and Arunachal Pradesh. The principal work components of the project include geological mapping, sampling and geochemical analysis of oil shale, shallow geophysical survey, shallow drilling for characterizing the oil shales, development of 3-D model and preliminary environmental studies. The project is expected to be completed in the third quarter of the FY 2009-10. Geological mapping and sampling program is in progress. Analytical studies in respect of 150 samples have been completed. Out of the total 3000m of planned drilling activity, about 2500m have been completed.

Phase-II (November 2009 to October 2011)
Once the resources of oil shale in the three blocks is determined with a reasonable degree of confidence, the following steps would be required to be taken:

• Techno-economic feasibility study for extraction of shale oil from these deposits. For the techno-economic analysis, a competent consultant will have to be hired who will carry out the study for DGH.
• Environmental impact assessment study by a reputed agency from India or abroad
• Framing of legislation for simultaneous extraction of coal and oil shale deposits. Since the oil shale occurs inter-bedded with the coal deposits, it follows that the oil shale industry will be supplementary and complementary to the coal mining industry. While the coal can be mined in the same way as it is being done now, the shale which is being discarded as waste would have to be processed for extraction of shale oil using a suitable retorting technology.
• Preparation of Model Production Sharing Contract. This study would have to be outsourced.
• Delineation of blocks for offer under first round of bidding for Oil Shale.
• Preparation of NIO, BEC etc.
• Obtaining necessary clearances from MoEF, MoHA and MoD for the blocks offered.

Phase-III (November 2011 to June 2012)

• Announcement of first round of bidding for oil shale
• Organizing Road shows in selected places
• Sale of data package
• Opening of data rooms
• Receipt of Bids
• Evaluation of Bids
• Award of Blocks