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The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 45 (1961)

Issue: 3. (March)

First Page: 411

Last Page: 412

Title: Nuclear Central America Hub of Antillean Transverse Belt: ABSTRACT

Author(s): J. H. Brineman, G. L. Vinson

Article Type: Meeting abstract

Abstract:

Nuclear Central America comprises the eastern part of the Sierra Madre del Sur geanticline and its flanking geosynclinal portion of the Gulf Coast and Caribbean embayments. Southeastern Mexico, Guatemala, British Honduras, Honduras, and Nicaragua make up the principal land area. Nuclear Central America disappears toward the east into the Caribbean Sea in easterly trending tectonic lineaments. The north flank of this geanticline is the crucial area for regional geologic interpretation.

The Mesozoic-Cenozoic Chapayal basin, or the eastern extension of the Chiapas foredeep, and the southern part of the Yucatan platform are the prime sedimentary areas involved. Chapayal basin, one of the local deep basins that ring and nearly surround the Gulf Embayment, is sharply asymmetric, having a steep and highly folded and faulted south limb and a gentle opposing limb which shelves northward over the Yucatan platform. The eastern part of the shelf area is interrupted by the Maya Mountain uplift in British Honduras which developed during the Paleozoic and was rejuvenated at the end of the Paleozoic. The Maya Mountains represent a remnant of an older Paleozoic hinterland that provided a source for later Paleozoic and Mesozoic sedimentation. It was a stable or slightly positive are during much of Mesozoic and Cenozoic time.

The Late Paleozoic-Mesozoic mobile belt, which sets the pattern for the geology of the nuclear Central America and the Antillean region, extends eastward

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from the mainland through the Greater Antilles. This mobile belt separates the Gulf and Caribbean regions, and the forelands to the bordering basins were in the Gulf of Mexico and Atlantic Ocean. The initial and main period of geosynclinal subsidence and sedimentation is Mesozoic in age; however, thick deposits were laid down during the Tertiary in the Chapayal basin and eastward in various island areas.

In nuclear Central America the sediments were derived, primarily, from the south and from an important older Paleozoic mobile belt and its subsequent ancient Maya Mountains-Cayman Basin landmass lying on the northwest flank of the Caribbean. The partly foundered northwest Caribbean hinterland, and the arcing of the Late Paleozoic-Mesozoic and Late Mesozoic mobile belt (which incorrectly suggest a foundered craton and surrounding rim syncline in the Antillean-Caribbean region) provide the basic framework for the tectonic relationships between North and South America. It is highly questionable that the Lesser Antilles is related in time with the earlier Late Paleozoic-Mesozoic mobile belt, but is more likely late Cretaceous and early Tertiary. The foundering of the Gulf craton occurred ith the beginning of the Mesozoic, and the initial deposits of the Gulf Embayment are the red-bed clastics and associated sediments of Triassic-Jurassic age.

The older and partly metamorphosed sediments in nuclear Central America and its environs include undifferentiated Carboniferous and older Paleozoic, and possible Precambrian. Younger unmetamorphosed sedimentary rocks are Permian, Triassic (?), Jurassic, Cretaceous, lower Eocene, Oligocene, and Late Tertiary in age and include one of the thickest Mesozoic evaporite sequences known in the world. Important orogenies are reflected in the sediments during all the major diastrophic events and during the early Oligocene. Intended as a principal contribution to the geology of the region is the introduction here of a supporting stratigraphic chart showing those formation names and ages which are accepted in Guatemala by the local Stratigraphic Nomenclature Committee.

A late Tertiary and Quaternary volcanic belt follows the Sierra Madre axis for a short distance in eastern Mexico and Guatemala and diverges southeastward through the remainder of Central America, forming the physiographic Rocky Mountain backbone.

No more than two dozen wells have been drilled for oil or gas in all northern Central America. Although the results have been negative, numerous encouraging shows indicate a future petroleum province. Evaporitic deposits in the Cretaceous and Jurassic limit the potential section of reservoir porosity. This poses no insurmountable problem, however, for explorationists utilizing thorough regional stratigraphic and tectonic studies.

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Copyright 1997 American Association of Petroleum Geologists