Geologists use four key attributes to define a continent:[1]
- Elevation – The landmass, whether dry or submerged beneath the ocean, should be elevated above the surrounding ocean crust.
- Geology – The landmass should contain different types of rock: igneous, metamorphic, and sedimentary.
- Crustal structure – The landmass should consist of the continental crust, which is thicker and has a lower seismic velocity than the oceanic crust.
- Limits and area – The landmass should have clearly-defined boundaries and an area of more than one million square kilometres.[lower-alpha 1]
With the addition of Zealandia in 2017, Earth currently has eight recognized geological continents:
† Usually considered a continent in the Oriental world/Eastern countries. Its land area includes Western New Guinea and the Aru Islands.
Submerged and Merged continents
- Zealandia.[2]
Due to lacking the presence of Precambrian cratonic rocks, Zealandia's status as a geological continent has been disputed by some geologists.[3] However, a study conducted in 2021 found that part of the submerged continent is indeed Precambrian, twice as old as geologists had previously thought, which is further evidence that supports the idea of Zealandia being a geological continent.[4][5]
All Eight geological continents are spatially isolated by geologic features.[6]
 | This article about a geographical location is a stub. You can help EverybodyWiki by expanding it. |
Notes[edit]
- ↑ In accordance with these attributes, Eurasia and North America are connected by a bridge of continental crust at least 2 thousand kilometers wide. And with Africa, Eurasia is connected by such a bridge (interrupted by internal sections of the oceanic crust) with a width of at least 5 thousand kilometers.
References[edit]
- ↑ "GSA Today – Zealandia: Earth's Hidden Continent". www.geosociety.org. Archived from the original on 17 February 2017. Retrieved 20 February 2020. Unknown parameter
|url-status=ignored (help) - ↑ Hunt, Elle (17 February 2017). "Zealandia – pieces finally falling together for continent we didn't know we had". The Guardian. Archived from the original on 25 October 2019. Retrieved 8 December 2023. Unknown parameter
|url-status=ignored (help) - ↑ "Chunk of an ancient supercontinent discovered under New Zealand". Science. 21 July 2021. Archived from the original on 21 July 2021. Unknown parameter
|url-status=ignored (help) - ↑ Woodward, Aylin. "A fragment of a mysterious 8th continent is hiding under New Zealand — and it's twice as old as scientists thought". Business Insider. Archived from the original on 2 October 2023. Retrieved 8 December 2023. Unknown parameter
|url-status=ignored (help) - ↑ Barsted, George (17 August 2021). "Ancient Continent Of Zealandia Raises New Questions For Geologists". Archived from the original on 10 May 2023. Retrieved 8 December 2023. Unknown parameter
|url-status=ignored (help) - ↑ "Earth's Hidden Continent Zealandia Finally Recognized". 4 October 2017. Archived from the original on 2 June 2023. Retrieved 8 December 2023. Unknown parameter
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