A maritime boundary is a conceptual division of Earth's water surface areas using physiographical or geopolitical criteria. As such, it usually bounds areas of exclusive national rights over mineral and biological resources, [1] encompassing maritime features, limits and zones. [2] Generally, a maritime boundary is delineated at a particular distance from a jurisdiction's coastline. Although in some countries the term maritime boundary represents borders of a maritime nation [3] that are recognized by the United Nations Convention on the Law of the Sea, maritime borders usually serve to identify the edge of international waters.
Maritime boundaries exist in the context of territorial waters, contiguous zones, and exclusive economic zones; however, the terminology does not encompass lake or river boundaries, which are considered within the context of land boundaries.
Some maritime boundaries have remained indeterminate despite efforts to clarify them. This is explained by an array of factors, some of which involve regional problems. [4]
The delineation or delimitation of maritime boundaries has strategic, economic and environmental implications (see maritime delimitation ). [5]
The terms boundary, frontier and border are often used as if they were interchangeable, but they are also terms with precise meanings. [6]
A boundary is a line. The terms "frontier", "borderland" and "border" are zones of indeterminate width. Such areas form the outermost part of a country. Borders are bounded on one side by a national boundary. [7] There are variations in the specific terminology of maritime boundary agreements which have been concluded since the 1970s. Such differences are less important than what is being delimited. [8]
Features that affect maritime boundaries include islands and the submerged seabed of the continental shelf. [2]
The process of boundary delimitation in the ocean encompasses the natural prolongation of geological features and outlying territory. The process of establishing "positional" borders encompasses the distinction between previously resolved and never-resolved controversies. [9]
The limits of maritime boundaries are expressed in polylines and in polygon layers of sovereignty and control, [10] calculated from the declaration of a baseline. The conditions under which a state may establish such baseline are described in the United Nations Convention on the Law of the Sea (UNCLOS). A baseline of a country can be the low water line, a straight baseline (a line that encloses bays, estuaries, inland waters,...) or a combination of the two. [1]
Maritime spaces can be divided into the following groups based on their legal status:
While many maritime spaces can be classified as belonging to the same group, this does not imply that they all have the same legal regime. International straits and canals have their own legal status as well. [11]
The zones of maritime boundaries are expressed in concentric limits surrounding coastal and feature baselines. [1]
In the case of overlapping zones, the boundary is presumed to conform to the equidistance principle or it is explicitly described in a multilateral treaty. [1]
Contemporary negotiations have produced tripoint and quadripoint determinations. For example, in the 1982 Australia–France Marine Delimitation Agreement, for the purposes of drawing the treaty's equidistant lines it was assumed that France has sovereignty over Matthew and Hunter Islands, a territory that is also claimed by Vanuatu. The northernmost point in the boundary is a tripoint with the Solomon Islands. The boundary runs in a roughly north–south direction and then turns and runs west–east until it almost reaches the 170th meridian east. [12]
The concept of maritime boundaries is a relatively new concept. [1] The historical record is a backdrop for evaluating border issues. [13] The evaluation of historic rights are governed by distinct legal regimes in customary international law, including research and analysis based on
The study of treaties on maritime boundaries is important as (a) as a source of general or particular international law; (b) as evidence of existing customary law; and (c) as evidence of the emerging development of custom. [15] The development of "customary law" affects all nations.
The attention accorded this subject has evolved beyond formerly-conventional norms like the three-mile limit.
Multilateral treaties and documents describing the baselines of countries can be found on the website of the United Nations. [1]
For example, the Australia–France Marine Delimitation Agreement establishes ocean boundaries between Australia and New Caledonia in the Coral Sea (including the boundary between Australia's Norfolk Island and New Caledonia). It consists of 21 straight-line maritime segments defined by 22 individual coordinate points forming a modified equidistant line between the two territories. [12]
Controversies about territorial waters tend to encompass two dimensions: (a) territorial sovereignty, which are a legacy of history; and (b) relevant jurisdictional rights and interests in maritime boundaries, which are mainly due to differing interpretations of the law of the sea. [16] An example of this may be reviewed in the context of the ongoing Kuwait-Iraq maritime dispute over the Khawr Abd Allah waterway.
Many disputes have been resolved through negotiations, [17] but not all of them.
Among the array of unsettled disputes, the maritime borders of the two Koreas in the Yellow Sea represent a visually stark contrast. [18]
A western line of military control between the two Koreas was unilaterally established by the United Nations Command in 1953. [21] [22] Although the North asserts a differently configured boundary line, there is no dispute that a few small islands close to the North Korean coastline have remained jurisdiction of the United Nations since 1953. [23]
The map at the right shows the differing maritime boundary lines of the two Koreas. The ambits of these boundaries encompass overlapping jurisdictional claims. [24] The explicit differences in the way the boundary lines are configured is shown in the map at the right.
In a very small area, this represents a unique illustration of differences in mapping and delineation strategies.
Violent clashes in these disputed waters include what are known as the first Yeonpyeong incident, the second Yeonpyeong incident, and the Bombardment of Yeonpyeong. [25]
The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea Treaty, is an international treaty that establishes a legal framework for all marine and maritime activities. As of October 2024, 169 sovereign states and the European Union are parties.
Territorial waters are informally an area of water where a sovereign state has jurisdiction, including internal waters, the territorial sea, the contiguous zone, the exclusive economic zone, and potentially the extended continental shelf. In a narrower sense, the term is often used as a synonym for the territorial sea.
Serranilla Bank is a partially submerged reef, with small uninhabited islets, in the western Caribbean Sea. It is situated about 350 kilometres (220 mi) northeast of Punta Gorda, Nicaragua, and roughly 280 kilometres (170 mi) southwest of Jamaica. The closest neighbouring land feature is Bajo Nuevo Bank, located 110 kilometres (68 mi) to the east.
Bajo Nuevo Bank, also known as the Petrel Islands, is a small, uninhabited reef with some small grass-covered islets, located in the western Caribbean Sea at 15°53′N78°38′W, with a lighthouse on Low Cay at 15°51′N78°38′W. The closest neighboring land feature is Serranilla Bank, located 110 kilometres to the west.
An exclusive economic zone (EEZ), as prescribed by the 1982 United Nations Convention on the Law of the Sea, is an area of the sea in which a sovereign state has exclusive rights regarding the exploration and use of marine resources, including energy production from water and wind.
The Northern Limit Line or North Limit Line (NLL) – 북방한계선 – is a disputed maritime demarcation line in the Yellow (West) Sea between the Democratic People's Republic of Korea (DPRK) in the north, and the Republic of Korea (ROK) in the south. This line of military control acts as the de facto maritime boundary between North and South Korea.
In Canadian law, Canadian Internal Waters are the waters "on the landward side of the baselines of the territorial sea of Canada."
The natural prolongation principle or principle of natural prolongation is a legal concept introduced in maritime claims submitted to the United Nations.
Malaysia and Vietnam are two Southeast Asian countries with maritime boundaries which meet in the Gulf of Thailand and South China Sea. The two countries have overlapping claims over the continental shelf in the Gulf of Thailand. Both countries have, however, come to an agreement to jointly exploit the natural resources in the disputed area pending resolution of the dispute over sovereignty.
The Fiji–France Maritime Delimitation Agreement is a 1983 treaty between France and Fiji which establishes the maritime boundary between Fiji and the French special collectivity of New Caledonia and the boundary between Fiji and the French overseas collectivity of Wallis and Futuna.
The Australia–France Marine Delimitation Agreement is a 1982 treaty between Australia and France which establishes ocean borders between Australian territories and French territories.
The Netherlands–Venezuela Boundary Treaty is a 1978 treaty between territory of the Netherlands and Venezuela which delimits the maritime boundary between territory of the Kingdom of the Netherlands and Venezuelan territory. When the treaty was concluded in 1978, the treaty set out the boundary between what was known as the Netherlands Antilles and Venezuela. Today, it establishes the boundary between Aruba and Venezuela, between Curaçao and Venezuela, and between the BES islands and Venezuela.
The equidistance principle, or principle of equidistance, is a legal concept in maritime boundary claims that a nation's maritime boundaries should conform to a median line that is equidistant from the shores of neighboring nations. The concept was developed in the process of settling disputes in which the borders of adjacent nations were located on a contiguous continental shelf:
An equidistance line is one for which every point on the line is equidistant from the nearest points on the baselines being used. The equidistance principle is a methodology that has been endorsed by the United Nations Convention on the Law of the Sea but predates that treaty and has been used by the Supreme Court of the United States, states, and nations to establish boundaries equitably.
There are disputes between China, Japan, Taiwan and South Korea over the extent of their respective exclusive economic zones (EEZs) in the East China Sea.
Qit'at Jaradah is a cay in the Persian Gulf to the east of Bahrain Island, located 32 km (20 mi) east of Manama, the capital of Bahrain. Historically, the feature was only above the water during spring low tide; it sits approximately midway between Bahrain and Qatar, within the 12-mile (19 km) territorial waters of both countries. It was one of several maritime features contributing to a long running dispute between Bahrain and Qatar.
The exclusive economic zone of North Korea stretches 200 nautical miles from its basepoints in both the Yellow Sea and the Sea of Japan. The exclusive economic zone (EEZ) was declared in 1977 after North Korea had contested the validity of the Northern Limit Lines (NLL) set up after the Korean War as maritime borders. The EEZ has not been codified in law and North Korea has never specified its coordinates, making it difficult to determine its specific scope.
The borders of Indonesia include land and maritime borders with Malaysia, Papua New Guinea, and East Timor, as well as shared maritime boundaries with Australia, India, Palau, Philippines, Singapore, Thailand, and Vietnam.