The Yucatán Platform is commonly defined as the continental platform constituted by the Yucatán Peninsula and its continental shelf.[1][2] As such, the margins of the continental shelf, or, more particularly, their 650 feet (200 m) isobaths or depth contours, are often taken as the platform's submarine limits.[2] Its subaerial limits (on the Yucatán Peninsula) are less precisely fixed.[citation needed]
The exposed or peninsular portion of the Yucatán Platform encompasses four districts of Belize (i.e., Corozal, Orange Walk, Belize, and Cayo), one department of Guatemala (i.e., Peten), and four states of Mexico (i.e., Quintana Roo, Yucatán, Campeche, and Tabasco).[4][3] Its submarine portion encompasses the continental shelf which abuts those of the aforementioned districts with a coast.[4][3]
Basins
At least three sedimentary basins have been identified in the Yucatán Platform, namely, the Campeche, Yucatán, and Peten–Corozal.[5]
Faults
At least six fault systems or zones have been identified in the Yucatán Platform, namely, the Holbox, Hondo, Ticul, Ring of Cenotes, Chemax–Catoche, and La Libertad, with the first four of these considered prominent.[6]
Geology
Formation
The Gulf of Mexico formed during a 70–90 million year rifting of Pangaea, which began some 240 million years ago, during the Middle Triassic, and ended some 170–150 million years ago, during the Middle or Late Jurassic.[7][8] The subaerially exposed (i.e., peninsular) portion of the platform is thought to have been fully submarine up to some 30–10 million years ago.[9]
Layers
Basement
The platform's crystalline basement is composed mainly of Precambrian to Palaeozoic granodiorite rocks.[10][11] It starts at a depth of some 2.3 miles (3.7 km) in the centre-point of the platform's exposed or peninsular portion, but steeps down towards the platform's eastern and northwestern extremes, starting at a depth of 3.4–3.7 miles (5.5–6.0 km) in the latter point.[12][9]
Cover
The platform's sedimentary cover is composed mainly of carbonates and evaporites formed during or after the Early Cretaceous.[1] It forms one of the largest deposits of carbonate minerals on Earth, with a depth range of 2.3–3.7 miles (3.7–6.0 km) .[13]
Notes
^The terms Yucatán Platform and Yucatán Shelf are sometimes used as a synonyms for the Yucatán Peninsula, i.e., the exposed portion of the Yucatán Platform (e.g., in Nairn & Stehli 1975, pp. 257–258 and Bundschuh & Alvarado 2012, p. 77, fig. 3.1). This article does not employ said usage.
French, C. D.; Schenk, C. J. (2004). Map showing geology, oil and gas fields, and geologic provinces of the Caribbean Region (Map). 1:2,500,000. Open-File Report 97-470-K. Reston, Virg.: U.S. Geological Survey. doi:10.3133/ofr97470K.
French, C. D.; Schenk, C. J. (2006). Map showing geology, oil and gas fields, and geologic provinces of the Gulf of Mexico region (Map). 1:2,500,000. Open-File Report 97-470-L. Reston, Virg.: U.S. Geological Survey. doi:10.3133/ofr97470L.
Mann, P., ed. (1999). Caribbean Basins. Sedimentary Basins of the World. Vol. 4. Amsterdam: Elsevier. ISBN0444826491. OCLC43540498.
Martens, Uwe (2009). Geologic evolution of the Maya Block (southern edge of the North American plate): An example of terrane transferral and crustal recycling (PhD). Stanford University.
Miranda-Madrigal, E.; Chavez-Cabello, G. (2020). "Regional geological analysis of the southern deep Gulf of Mexico and northern Yucatán Shelf". Special Publications of the Geological Society of London. 504 (sn): 183–204. doi:10.1144/SP504-2020-1. S2CID225750222.
Steel, I.; Davidson, I. (2020a). The basins and orogens of the Southern Gulf of Mexico map (Map). 1:4,000,000. Special Publications; v. 504; pp. 557-558. London: Geological Society of London. doi:10.1144/SP504-2020-2.
Steel, I.; Davidson, I. (2020b). Map of the geology of the Northern Caribbean and the Greater Antillean Arc (Map). 1:4,000,000. Special Publications; v. 504; pp. 559-560. London: Geological Society of London. doi:10.1144/SP504-2020-3.