Notes on the Geology of the Island of Cuba; Based Upon a Reconnoissance Made for Alexander Agassiz


Book Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 edition. Excerpt: ... aooH pas-oiozojsao-AHVIIH3X Coal in the Isthmian Tertiary.--The older Tertiary sediments of the Isthmian region are characterized by lignite. The presence of these coals in extensive beds is strong evidence of the close proximity of large land areas during the epoch of their deposition. While at Colon, Colonel Rives, Superintendent of the Railway, informed me of several coal deposits to the north of the road, especially one of unusual interest on the Rio Indios, a confluent of the Chagres, rising along the divide north of the town of Chorera. Commander Lull's Report1 gives all the known geological information concerning these localities. Still westward on the Isthmian region the coal bearing sandy clays have great development around the Chiriqui Lagoon, where they were studied in the year 1857, by Dr. John Evans. In his report he says: "On microscopic examination of their fragments and of the ashes of the coal when burnt, the structure of cellular plants which formed it is discerned quite distinstly. The fossil plants, leaves, etc., associated with the coal, were endogenous and allied to or identical with those at present growing in the vicinity." Later these shells were studied by Dr. C. T. Jackson,2 who stated that, judging from the fossils, such as Cardum, Cerethium, ISTatica, Mytilus, and other shells, this coal belongs to the Upper Eocene Period. They were also studied by Gabb,8 who referred them to the "Miocene," which is the Oligocene of this paper. The fossil shells are all Eocene or Miocene Tertiary (salt water shells); none older were discovered in the coal formations. The observations of Gabb in the eastern lying province of Talamanca. and of Sapper in Guatemala and Chiapas, show that these lignites are a marked characteristic...







Geology of Cuba


Book Description

The evolution of geological cartography in Cuba in its more than 135 years of history has been possible through the consultation of numerous archival reports, publications, maps and personal interviews with different authors and geologists of vast experience. A brief critical analysis is made of the increase in the degree of geological knowledge of the country since the elaboration of the Geological Sketch of the Cuban Island at a scale of 1: 2 000 000 (Fernández de Castro, 1883), first of Cuba and of Ibero-America, until the most recent Digital Geological Map of Cuba at scale 1: 100 000 (Pérez Aragón, 2016). Cuba and its surroundings are a geological mosaic in the southeast corner of the North American plate with rocks from many different origins, from Proterozoic to Quaternary, extended along the southern border of the plate. From the Eocene, this belt has been dissected by several great faults, related to the development of some great oceanic depressions (Cayman trough and Yucatan basin). The fossil record of Cuba, which covers approximately the last 200 million years of life on Earth, is rich in very varied fossils, witnessing a wide diversity of organisms, both animals and plants, that inhabited the Antillean and Caribbean region; and that constitute the inheritance of the biological diversity that the current Cuban archipelago exhibits. As a result of the preparation of the Cuban Metallogenic Map at scale 1: 250 000, forty-one models and eight sub-models of metallic mineral deposits were identified. These models, of descriptive–genetic type, together with the analysis of their spatial distribution and their relationship with geology, allowed the identification and mapping of ten mineral systems, linked to the geodynamic environments present in the Cuban territory. Cuba has large deposits of limestone, loam, dolomite, kaolin, gypsum and anhydrite, rock salt, marbles, sands and clays of different types, zeolites, peat, therapeutic peloids and many more. There are manifestations of decorative and precious rocks such as jasper, jadeite, different varieties of quartz and even xylopals. A compilation of geochemical data of oceanic basalt samples from previous works, together with data of analyzed samples during this study in order to discuss geochemical criteria based on immobile element (proxies for fractionation indices, alkalinity, mantle flow and subduction addition), provide a comprehensive ophiolite classification according to their tectonic setting. This book addresses different facets of the geological knowledge of Cuba: history of its cartography, marine geology, fossil record, stratigraphy, tectonics, classification of its ophiolites, quaternary deposits, metallogeny and minerageny.