Lies multi-billion barrels of oil and hundreds trillion cubic feet of natural gas
by Eng. Abdulkadir Abiikar Hussein
Wednesday, January 29, 2014
One of the newest, most promising areas for deep-water exploration is offshore East Africa, from Somalia to South Africa or the Western Indian Ocean. At least three-quarters of global deep-water spending, historically has focused on the Deep-water Golden Triangle: offshore Brazil, the Gulf of Mexico and offshore West Africa. But over the past few years, a number of giant fields have been discovered outside this traditional core, prompting international oil companies to ramp up investment in these emerging plays of the East African Indian Ocean. Though most of the gas discoveries occurred in Mozambique and Tanzania; and one discovery is in Kenya (which is under evaluation now), Somalia missed out due to conflict and anarchy that prevailed for more than two decades.
Somalia’s portion: A major portion of the East African margin of the Indian Ocean is owned by Somalia, which is lagging behind relative to Kenya, Tanzania, Mozambique Madagascar and Seychelles in terms of the exploitation of marine resources. Somalia is just emerging out of two decades of instability and got its government recognised by USA, UK and others recently. From here Somalia has to embark on the road to build the institutions related to the advancement of petroleum sector.
Why offshore Somali Indian Ocean becomes so important now?
Offshore Somali coast shares the same geological past with the rest of East Africa and East African countries (Mozambique, Tanzania, Kenya and Madagascar) have made oil and gas discoveries recently. Some of the discoveries were giant gas fields. Ethiopia discovered gas in Halala and Calub near Wardheer in the seventies, a discovery equivalent to 4 Trillion cubic feet of gas. However, in the past, deep-ocean drilling and the related technologies faced challenges and at present the following has changed:
· The emergence of more productive new drilling techniques and technologies: Significant advances in exploration technology, such as large-area 3D seismic surveys, have reduced the risks in predicting reservoir distribution, facies architecture and trapping geometries.
· The growth of the liquid natural gas market: Demand for liquid natural gas is growing and it is pushing companies with exploration
· The renaissance in deep-water exploration
Evolution of the geology of the margin:
The East African margin has undergone somewhat similar successive evolution that produced the current margin and below is a summary of that evolution:
It all started at the Late Paleozoic –Early Mesozoic (550 – 200 my ago) when the super-continent, called Gondwana in the southern hemisphere started to break apart. Before the fragmentation, the super-continent extended, sagged and formed a massive basin, the Late Carboniferous-Early Jurassic Karroo rift basins. Continents such as South America, Africa, Antarctica, Australia, and smaller pieces (plates) such as India, Arabia, Madagascar and some islands such as Seychelles, Mauritius and Sri Lanka broke from the supercontinent and drifted away to their present locations relative to Africa. As time went on, the continental margin was slowly evolving due to the sea transgression, regression caused by tectonic forces causing movements: compression, extension and uplifting. The margin as it is shaped today was formed finally in Oligocene (35 – 25 my) and Miocene (25 – 5 my). Thus, the resulting East African Margin and SW Indian Ocean basins evolved from the rift-drift tectonics of Gondwana.
According to Bosellini, Alfonso; Coffin, MF and to some extent the work of Harms, John C.; Mackenzie, D; Lowell, J and Wray J in Harms and Brady in their “Evaluation of Hydrocarbon Potential of all of Somalia, the Indian Ocean margin of Somalia can be divided into 4 zones:
1. The continental margin bordering northern Mozambique, Tanzania and most of Kenya (up to 2.5 degrees S) has experienced similar evolution. No part of this margin is in Somalia.
2. The margin of NE Kenya from 2.5 S to 6 degrees N, corresponding to Qallad, a small settlement north of Hobyo. This margin was formed during the Jurassic (150 – 160 My ago) by rifting and drifting of Madagascar from Somalia and Kenya.
3. The Northeast sector of Somalia, from 4-5 degrees North to Socotra was formed by the rifting of India and then drifting away to where India is now. India followed the Owen Fracture and the Chain Ridge.
4. The north Somalia continental margin was formed from the separation of Arabia from Africa. Thus the Gulf of Aden and the Red Sea were formed.
Sedimentary basins were formed (where oil and gas accumulates):
Sedimentary provinces were formed by basins being filled up with sediments at different times. Some basins were formed before (pre-rift); some basins were formed during (sin-rift) and some basins were formed after the break-up of Gondwana super-continent. Provinces with high potential in oil and gas were formed along the Indian Ocean margin of East Africa. In East Africa including Somalia, various sedimentary provinces formed include: Cratonic sag basins, Karroo Rift basins, Mesozoic Rift basins, coastal basins, deep-water channels, Davie Ridge structural trend, East African Tertiary rift basins (West and East branches), and Red Sea Miocene salt basins. The Yemani-Oman basins add Precambrian to Cambrian salt and Jurassic Rift Basins. The carbonate over volcanic accumulation of the western Indian Ocean provides an additional, but it is non-prospective. With the sole exception of the carbonate-over-volcanic sedimentary province, each of the provinces mentioned above are areas containing numerous attractive plays, leads and even mapped and untested prospects. Each country has an inventory of the plays, leads and prospects within its borders.
East African Margin of the Indian Ocean experience more exploration since 2010:
Offshore East Africa did not have the attention that the passive West African margin had. Oil-gas industry had done only some sporadic effort and none in the deep-water regions. But all that changed thanks to the Cold War activities. The Russians and the French wanted their submarines to move freely out of danger. So it was import for them to carry out submarine surveys: bathymetric, magnetic, gravimetric and seismic reconnaissance of the sea-floor. These surveys turned out to be useful for oil/gas industry. Professionals from the industry caught their eyes on a fractured zone that previously was considered a volcanic zone, but which turned to be a transform fault zone. The new view changed geologists to start exploration with a new model in their practice and started discovering abundant oil and gas
Although oil exploration in the East African Margins began in the 1950s, and some discoveries were made in the past, the East African Margin has attracted international oil companies for its major deep-water gas discoveries offshore Tanzania and Mozambique since 2010. Following that, the news of gas and oil discoveries is hitting the ears of global professionals.
Discoveries followed the exploration!
A recent USGS report estimated undiscovered, recoverable oil resources of 28 billion barrels of oil and 441 trillions of cubic feet of natural gas for the Mesozoic– Cenozoic sediments of Tanzania, Mozambique, Madagascar and Seychelles combined. In the space of a few years, East Africa has become a feeding ground for most of the world’s oil majors, which have sniffed the region’s oil and gas resources estimated to be massive. Discovery after discovery of oil and gas is making East Africa a rich hunting ground for global explorers.
|
Country |
Company name |
Field name |
Recoverable oil/gas resources in
Tcf = Trillion cubic feet and
MMBbl = Millions of barrels of oil |
|
Mozambique |
Anadarko (USA)
ENI (Italian) |
Area 1
Area 4 |
100 Tcf (Tcf = Trillion cubic feet)
70 Tcf |
|
Madagascar |
Madagascar Oil |
Tsimiroro |
1.7 MMBbl of heavy oil
|
|
Seychelles |
Is getting ready for bid rounds of its acreages.
|
|
Tanzania |
Ophir (UK)
Statoil (Nor)
BG (UK) |
Pweza, Chewa and Chaza
Zafarani – Block2
Blocks 1,3 and 4 |
7 Tcf
9 Tcf
7 Tcf |
|
Kenya |
Apache Cons. (USA) |
L8 - Malindi |
7Tcf
|
|
Somalia |
Is structuring its petroleum sector (legislation and institutions) and wants to join the race to tap the unexploited resources! Somalia is a “hotspot”.
|
Conclusion:
As the scrambles for concessions in the coastal East African countries continue, experts believe there is a high probability of a gas find along the Somali coast and its deep seas which shares the same geological evolution as in the gas-rich blocks in Tanzania, Mozambique and recently Kenya.
Somali Petroleum Authority, Somali National Oil Corporation and the Ministry of Mineral and Petroleum Resources will combine their effort in order to revise the Petroleum Law and make it attractive and competitive, carry out seismic, gravimetric, magnetic survey and execute the mapping of the Somali part of the Indian Ocean and dividing it into exploration blocks ready for bidding rounds to take place. In addition Somalia has to delimit its offshore border with Yemen (Gulf of Aden and Socotra) and with Kenya in the southeast amicably without creating conflicts. All that need to happen quickly in order to meet the on-going level of interest of international oil and gas exploration companies for Somalia’s offshore.
References:
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1. Bertagne, R. and Rusk, D.C; New Petroleum Exploration Concepts Related to the Davie Fracture Zone, Offshore East Africa, AAPG International Conference and Exhibition, Sept. 21-24, 2003; Barcelona, Spain
2. Bosellini, A.; The continental margins of Somalia – Structural Evolution and Sequence Stratigraphy; Geology and Geophysics of Continental Margins, 1992; AAPG Special Volumes; 1992.
3. Chris Matchette - Downes; Finding hydrocarbons in East Africa and the Western Indian Ocean. Finding Petroleum Conference, London, 21 – 22th January 2010.
4. ________; East African Exploration – Myths, Myopia and Misinformation; Frontier Exploration. Geo Ex-Pro; October 2007; pp: 16 – 20
5. Coffin, Millard F. and Rabinowitz, Phillip D.; Evolution of the conjugate East African – Madagascan margins and the Western Somali Basin. Special Paper 226, The Geological Society of America, 1988.
6. Mark Townsend and Tarik Abdinasir; The Observer: 25 Feb. 2012. Britain leads dash to explore for oil in war-torn Somalia.
7. Duale, A. and Mbede, E.I.; 1997. The coastal basins of Somalia, Kenya and Tanzania. In RC Selly (Editor: African basins; sedimentary basins of the world. Elsevier, Amsterdam: 211 – 236.
8. Gue, Elliotte H.; East Africa’s Energy Boom; Energy Stocks, Investing Daily, 6th September 2012.
9. Rayer F.G. (SR Du Toit) and Slind O.L (Al-consult International); Hydrocarbon potential of the East African Continental Margin – From Somalia to South Africa; an EARHS project of Canadian International Development Agency (CIDA) and NOCs.
10. Rasoul Sorkhabi et al.; East African margin and SW Indian Ocean basins; Energy and Geoscience Institute, University of Utah. 2012.
11. Sandrea Ivan and Enfield Monica; New strategies on horizon for exploration companies; Oil & Gas Journal, March 2012.
12. Shirley, Kathy; Big East Africa Structures Enticing, Explorer, July 2003.
13. St. John, Bill; Eastern Africa Offshore; 25th Annual GCSSEMP Foundation Bob F. Perkins Research Conference, Dec. 4-7, 2005, Houston, TX, USA
14. Thevanayagam, Lydia et al; Regional Report: Offshore Africa; World Oil, August 2012.
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Abdulkadir Abiikar Hussein
[email protected]