A landmass, or land mass, is a large
region or area of
land that is in one piece and not noticeably broken up by
oceans.[1][2] The term is often used to refer to lands surrounded by an ocean or
sea, such as a
continent or a large
island.[3][4] In the field of
geology, a landmass is a defined section of
continental crust extending above
sea level.[5]
Continents are often thought of as distinct landmasses and may include any islands that are part of the associated
continental shelf. When multiple continents form a single contiguous land connection, the connected continents may be viewed as a single landmass.
Earth's largest landmasses are (starting with largest):[6][7][8]
Continental landmasses are not usually classified as islands despite being completely surrounded by water.[Note 1] However, because the definition of continent varies between geographers, the
Americas are sometimes defined as two separate continents while
mainland Australia is sometimes defined as an island as well as a continent. Nevertheless, for the purposes of this list, mainland Australia along with the other major landmasses have been listed as continental landmasses for comparison. The figures are approximations and are for the four major continental landmasses only.[Note 2] The artificial
Panama and
Suez canals are disregarded, as they are not natural waters that separate the continents.
48 countries on mainland Africa[Note 5] and 78 countries on mainland Eurasia (38 countries on continental Asia[Note 6] and 40 countries on
continental Europe[Note 7]). Two states on mainland Africa and five states on mainland Eurasia (three states on continental Asia[Note 8] and two states on continental Europe).
Antarctica is a special case, for if its ice is considered not as land, but as water, it is not a single landmass, but several landmasses of much smaller area, since the ice-bedrock boundary is below sea level in many regions of the continent.[13] If its ice cover were to be lifted, some rocks that are currently below sea level would
rise as the weight of the ice would be removed,[14] although this would in part be counteracted, and in some areas of the continent overtaken, by
eustatic rises in
sea level.[15]
Mainland Australia is more than three times the size of
Greenland, the largest island.[17] Australia is sometimes dubbed "The Island Continent" or "Earth's largest island, but its smallest continent".[18]
^The
United States Geological Survey is a notable exception. The United States-based scientific agency considers all landmasses surrounded by ocean water, including continental
mainlands, as islands. Under their definition, Africa, Australia,
Eurasia, North America, and South America are classified as continental mainland islands.[9]
^Physiographically, there are only four continents (including offshore
continental islands which sit on the nearby
continental shelves) that are completely surrounded by water:
Afro-Eurasia (57% of the global land area), the Americas (28.5%), Antarctica (9%), and
Australia (5%). The remaining 0.5% is made up of remote
oceanic islands, mostly scattered within
Oceania in the central and south
Pacific Ocean.[10]
^Including landmasses which are above water and over 2,500,000 km2 (970,000 sq mi). The
submerged continent of
Zealandia (approx. 5,000,000 km2 (1,900,000 sq mi)) is excluded.[11]
^Figure derived from the
Global Islands Explorer website, by adding the areas of mainland Africa (29,370,907 km2 (11,340,171 sq mi)) and mainland
Eurasia (50,439,819 km2 (19,474,923 sq mi)).
^Figure derived from the
Global Islands Explorer website, by adding the areas of mainland North America (20,090,075 km2 (7,756,821 sq mi)) and mainland South America (17,609,548 km2 (6,799,084 sq mi)).
^Depending on
the definition, a significant portion of
Panama (land east of the
Panama Canal) could be considered a part of mainland South America.
^Area of mainland Antarctica, without the ice shelves and nearby islands.[12]
^Figure derived from the
Geoscience Australia website, the area of mainland
Tasmania (64,519 km2 (24,911 sq mi)) has been deducted.[16] The
Global Islands Explorer website has given a slightly larger figure of 7,618,696 km2 (2,941,595 sq mi) for the area of mainland Australia.
References
^"Landmass". Cambridge Dictionary. Cambridge.org Dictionary. Retrieved 17 January 2023.
^"Landmass". Merriam-Webster. Merriam-Webster.com Dictionary. Retrieved 17 January 2023.
^R.W. McColl, ed. (2005).
"continents". Encyclopedia of World Geography. Vol. 1. Facts on File, Inc. p. 215.
ISBN978-0-8160-7229-3. Retrieved 25 August 2022. And since Africa and Asia are connected at the Suez Peninsula, Europe, Africa, and Asia are sometimes combined as Afro-Eurasia or Eurafrasia. The International Olympic Committee's official flag, containing [...] the single continent of America (North and South America being connected as the Isthmus of Panama).