Cover Story 2 Non-Living Ocean Resources Introduction Two thirds (2/3) of the surface of the earth is covered by oceans. Resources from the oceans are essential to meet daily needs of mankind. Ocean resources are of two types, living and non-living resources. Fishes and other microscopic and macroscopic organisms in oceans are living resources in oceans. Main nonliving ocean resources are mineral resources, crude oil, natural gas and gas hydrates. Potential non-living ocean resources in Sri Lanka which could have a huge positive impact on national development include mineral resources, crude oil, natural gas and gas hydrates. D.M. Upul Premarathne Offshore Areas Belonging to Sri Lanka According to the United Nation's Convention on the Law of the Sea (UNCLOS), Sri Lanka could claim ownership of an offshore area referred to as the Exclusive Economic Zone (EEZ), which is approximately 517,000 squire kilometers and 8 times the land mass of the island. Outer boundary of the EEZ is 200 nautical miles (370 km) from a baseline which coincides more or less with the coastline of Sri Lanka. However, the 200 nautical mile criterion is not applicable on the western sides of the country where the international maritime boundary between Sri Lanka and India have been settled by an agreement of 1974 and 1976 (Figure 1 & 2). Sri Lankan Government has the exclusive rights for living and non-living resources in the water mass, the sea bed and the sediments in the EEZ. Water depth is most areas of the EEZ is well over 3000 meters, and current technology is neither capable nor economical to tap petroleum deposits in areas of such depths. It is expected that exploration and recovery technology would develop over the years and such inaccessible deposits could be economically exploited in the future. According to general provisions under the article 76 of the Law of the Sea, coastal states like Sri Lanka have Figure 1: Exclusive Economic Zone (EEZ) and the proposed outer boundary of the continental shelf of Sri Lanka depicted in red circles (Source: Executive Summary of Continental shelf submission of Sri Lanka been able to claim an offshore area beyond the EEZ up to a limit where sediment thickness is not less than 1 km. Over the millennium, a large amount of sediments have become deposited in the Bay of Bengal mainly by two Indian rivers, the Ganges and Brahmaputhra. The thickness of sediments deposited in the Indian Ocean gradually diminishes from the coastline of Sri Lanka. Sri Lankan Government launched a project called Delimitation of the Outer Edge of the Continental Margin of Sri Lanka to determine the outer limit of the offshore area beyond EEZ based on the above criterion. The Government of Sri Lanka submitted its proposal on the outer margin of the continental shelf to the United Nation's Commission on Limits 10 VIDURAVA VOLUME 27 NUMBER 02
Indo-Lanka Maritime Boundary Figure 2: Block 5 6644 km 2 Block 2 3338 km 2 Block 3 3572 km 2 Block 4 4127 km 2 Block 6 3567 km 2 Block 1 3501 km 2 Block 7 3970 km 2 Block 8 4995 km 2 Location of Mannar, Cauvery and Southern Offshore Basins. Blocks 1 to 8 covers the Mannar Basin of the Continental Shelf (UNCLCS) on 08th May 2009. If the commission accepts this proposal the country will get an offshore area beyond EEZ which is approximately 17 times the size of its landmass (Figure 2). In this newly proposed offshore area, the Sri Lankan Government can claim non -living resources in the sediment column. The main non-living resources that might be associated with marine sediments of Crude oil is such a valuable non-living resource that it is referred to as black gold. Brownish black in colour, its demand in the world market has resulted in it being referred to by this name. this area include mineral resources, crude oil, natural gas and gas hydrates. Non-Living Ocean Resources Crude Oil and Natural Gas (Petroleum) Crude oil is such a valuable non-living resource that it is referred to as black gold. Brownish black in colour, its demand in the world market has resulted in it being referred to by this name. Crude oil is mainly composed of the hydrocarbons paraffin, napthene and aromatic hydrocarbon series. Physical properties of crude oil vary with types of hydrocarbons and their proportions. Natural gas is mainly composed of the first four members of the paraffin series, methane (CH 4 ), ethane (CH 6 ), propane (C 3 H 8 ) and butane (C 4 H 10 ). Pentane (C 5 H 12 ) could be a constituent of natural gas when it is trapped in sediments deep below the earth. However, it is a liquid under ambient conditions and get condensed at the earth surface which is then referred to as gas condensates. In the strictest sense the word petroleum, which is a Greek word meaning rock oil, is a reference to refer to crude oil. However, in common usage petroleum is used for both crude oil and natural gas. Accordingly, the word petroleum in this article includes both crude oil and natural gas. Crude oil and natural gas are believed to be of organic origin. Therefore, petroleum is not a mineral or categorized under mineral resources. Petroleum is trapped in sediments deposited on land as well as offshore. Countries like Saudi Arabia, Iraq and Iran have on-land petroleum deposits while countries like Norway, Nigeria and the United Kingdom have offshore deposits. Searching for petroleum is referred to as petroleum exploration. Exploration and production of petroleum is referred VIDURAVA VOLUME 27 NUMBER 02 11
Non-Living Ocean Resources to as upstream petroleum industry. Refining of crude oil and transport of petroleum products (gasoline, diesel, kerosene etc.) and petrochemicals are referred to as downstream petroleum industry. Upstream petroleum industry began in on-land. However, these days petroleum exploration is mostly done offshore. Petroleum exploration in offshore areas is relatively more difficult and expensive than in on land. The greater the water depth the higher the risk and cost of exploration. Nevertheless, today's technology is capable of undertaking petroleum exploration and production in water as deep as 3000 meters. A country having its own petroleum reserves means a great strength to its economy. No petroleum deposit has been discovered in Sri Lanka yet. Therefore, the country's entire demand for petroleum is supplied by petroleum imports. In 2008, Sri Lankan Government spent more than US $ 3368.2 million for crude oil importation. This amount is about 8.28 % of the country's Gross Domestic Product (GDP) of the same year. This is a significant amount of money. If we had our own petroleum reserves the country could have saved this colossal amount of money which could have been allocated for development projects. On the other hand, if there was a surplus in petroleum production over national demand, this surplus could have been a foreign exchange earner. A particular area of the earth where sediments are deposited is referred to as a sedimentary basin. Sri Lanka has three offshore basins with higher petroleum potential indicated by geophysical data. They are Mannar, Cauvery and Southern Offshore Basins (Figure 2). History of petroleum exploration in Sri Lanka dates back to 1957. In the 1970s, six exploration wells were drilled into the Cauvery Basin. A well drilled at Pasalai on the Mannar Island had shown traces of gas indicating possibility of having petroleum deposits in the Cauvery Basin. However, this initial petroleum exploration was abandoned in 1984. After a dormant period of nearly 17 years, Sri Lanka resumed petroleum exploration in 2001. A Norwegian geophysical company named TGS-NOPEC acquired 5600 km two dimensional (2D) seismic data in the Mannar Basin during 2001 and 2005. These data have shown that the Mannar Basin has greater potential to have petroleum deposits of economic significance. To support petroleum exploration, the Sri Lankan Government established the Ministry of Petroleum Resources Development in 2003. The Mannar Basin was divided into 8 exploration blocks (Figure 2). The blocks 1 and 8 have been offered to India and China respectively. In 2007, the ministry called for bids from international oil companies to explore petroleum in blocks 2, 3 and 4 of the Mannar Basin. An Indian oil company known as Cairn India Limited won the bids for the block No. 2. A Petroleum Resources Agreement was signed between the Sri Lankan Government and Cairn on 07th July 2008 and on this day Cairn paid US $ 1 million to Sri Lankan Government as a signature bonus. Cairn has started petroleum exploration in the block No 2 of the Mannar Basin now, and they pledge to invest US $ 112 million during the first three years of exploration. They intend to start exploratory drilling in January 2011, and the results of drilling would probably be available by the end of 2011. There is a greater possibility that Cairn would strike a petroleum deposit in block 2 of the Mannar Basin. A particular area of the earth where sediments are deposited is referred to as a sedimentary basin. Sri Lanka has three offshore basins with higher petroleum potential indicated by geophysical data. The Cauvery Basin is shared by both India and Sri Lanka. India has discovered petroleum and natural gas in the Indian side of the Cauvery Basin. Therefore, Cauvery Basin is now classified as a category 1 basin, which means a basin having proven commercial production of petroleum. Accordingly, there is a greater possibility of having petroleum deposits in Sri Lanka s Cauvery Basin. Blocks 3, 4 5, 6 and 7 of the Mannar Basin, Cauvery and Southern Offshore Basins will be offered for petroleum exploration in future bidding rounds. The goal of Petroleum exploration is to make 12 VIDURAVA VOLUME 27 NUMBER 02
Non-Living Ocean Resources Sri Lanka a petroleum producing county. However, within the exploration period itself the country can still harness a lot of benefits such as new job opportunities and earning of foreign exchange. Methane Hydrates On Earth methane hydrates can be found on sea floor or in ocean sediments. Methane hydrates physically resemble ice, in which methane molecules are trapped in cages of hydrogen bonded water molecules (Figure 3). It is estimated that 6.4 trillion tons of methane are trapped in world reserves of methane hydrates. Methane hydrate is a prospective energy source (Figure 4). Possible methods of methane hydrate exploitation are still at research level. However, development of extraction methods of methane hydrates is a possibility, and it is expected that this valuable energy source will become useful in power generation in the future. Mineral Resources Main mineral resources in the ocean include elements and compounds dissolved in sea water, mineral sands, manganese and prosperitie nodules deposited on the sea bed. One of the important compounds extracted from sea water is salt (NaCl). A major component of the county s salt demand is from the salt produced in salterns in Hambanthota and Puttalam areas. In addition, gypsum (CaSO 4.2H 2 O), magnesium (Mg), potassium (K) and bromine (Br) are some of economically important constituents extracted from sea water. Mineral sands which could be deposited in offshore areas belonging to Sri Lanka include ilmenite (FeTiO 3 ), rutile (TiO 2 ), zircon (ZrSiO 4 ), monosite and garnet. The black coloured heavy mineral deposited on the western coastline of Sri Lanka is composed mainly of ilmenite. While the red coloured sand abundantly found on southern coastline specially around Hambanthota area is garnet. These two types of Figure 3: Structure of methane hydrates. Water molecules have formed crystalline lattice and yellow, red and green solids resemble methane molecules (Sources: URL) Figure 4: mineral sands on the coastline may be an indication of the occurrence of large ilmenite and garnet sand deposits in the western offshore of Sri Lanka Manganese nodules are potato like rock concretions 5 to 20 cm in diameter, and formed as concentric layers of manganese hydroxide precipitated around a core. Manganese nodules are considered to be a source of nickel (Ni). The commercial production of manganese nodules is not viable due to the availability of cheap onshore sources of nickel. An estimated 500 billion tons of manganese nodules are believed to be lying on the world s ocean floors. Potential methods of nodular extraction are still under research level. Occurrence of manganese nodules in the offshore area belonging to Sri Lanka is remote, because of the high rate of sediment influx into the Bay of Bengal which is believed to hinder nodular growth. However, there is a slim possibility of the occurrence of manganese nodules in the southern and southeastern periphery of the Sri Lanka s continental shelf. D.M. Upul Premarathne Economic Research Department Central Bank of Sri Lanka Burning methane hydrates (Sources: URL) VIDURAVA VOLUME 27 NUMBER 02 13