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USGS · 70020757

Geology of Isla de Mona, Puerto Rico

E.F. Frank·Carol M. Wicks·J. Mylroie·J. Troester·E.C. Alexander·J.L. Carew
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Abstract

Isla de Mona is a carbonate island located in the Mona Passage 68 km west of Puerto Rico. The tectonically uplifted island is 12 km by 5 km, with an area of 55 km2, and forms a raised flat-topped platform or meseta. The meseta tilts gently to the south and is bounded by near vertical cliffs on all sides. These cliffs rise from 80 m above sea level on the north to 20 m above the sea on the southern coast. Along the southwestern and western side of the island a three- to six-meter-high Pleistocene fossil reef abuts the base of the cliff to form a narrow coastal plain. The meseta itself consists of two Mio-Pliocene carbonate units, the lower Isla de Mona Dolomite and the upper Lirio Limestone. Numerous karst features, including a series of flank margin caves primarily developed at the Lirio Limestone/Isla de Mona Dolomite contact, literally ring the periphery of the island.

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E.F. Frank, Carol M. Wicks, J. Mylroie, J. Troester, E.C. Alexander, J.L. Carew. 1998. Geology of Isla de Mona, Puerto Rico. https://pubs.usgs.gov/publication/70020757

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