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Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New U-Pb in zircon ages obtained in metamorphic units of the Puquí Complex and the Valdivia Group, from a sector in northwestern Antioquia, between the Central and Western Cordilleras of the Northern Andes, evidence three different regional geological events: 1) crystallization ages during the Ordovician (La Vereda Rodriguez Gneiss), comparable to ages obtained further east and south in the La Miel Gneiss and La Perla Gneiss; 2) Metamorphism and anatectic metamorphism during the Middle Triassic (Pescadero Gneiss, Toledo Porphyroblastic Gneiss, Puente La Palesti°na Amphibolites, and ages in deformed rocks), a regional event common to other gneissic bodies of the Central Cordillera in the Tahamí Terrane; 3) maximum Cretaceous depositional ages (ca. 72 Ma) in a biotite-moscovite-quartz schists unit, similar to those obtained in metamorphic and deformed rocks in the western margin of South America, and interpreted as a result of the collision of the oceanic Plateau against the continental margin. We propose a new nomenclature for previously mapped units within the Puquí Complex, such as the La Vereda Rodríguez Gneiss, the Toledo Porphyroblastic Gneiss, and the Puente La Palestina Amphibolites, based on geochronology results and existing mapping. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geominas is the property of FUNDA-GEOMINAS. (Fundacion de Egresados d Amigos de la Escuela de Ingenieria Geologica y de Minas) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since the Renaissance, the pageantry and theatrality associated with power are based on a celebratory tradition which is mainly urban. The purpose of this paper is to reflect on the transposition of this festive model to colonial America and, in particular, to analize the performances of the mestizo ephemeral found on the outskirts of the colonial city in New Spain, in different spaces and farther away from the locations of mainstream power centres. [ABSTRACT FROM AUTHOR]

Abraham Ortelius, the author of the most important cosmography of his time, spoke of himself as a passionate "reader" of maps. According to his proposal, maps work not as documents, but as stories with a capacity for argumentation, intrigue, discursive course and climate conclusion. However, their reading, at least in their colonial mode, is full of dangers, especially if they portray marginal regions, borders and peripheries with respect to the centre of imperial power. On some of these occasions, changes, tropisms, alterations and mixtures occur on the sides of the representation that make the map a hypertext with a strong index load, in a less semiotic than Benjaminian sense of the term and, therefore, capable of going beyond its first referential and illustrative condition. This article studies the configuration of viceregal America and its margins as an "anomalous" space of representation, with the help of an engraving of the city of Cuzco that offers in its strange and anachronistic walls quotes from a peripheral reality, heterogeneous and imprecise. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Four paleogeographic and paleotectonic domains are present in the Cuban Mesozoic sections. They are, from north to south: 1- Northern sequences of passive paleomargin type (NPP), 2- The northern ophiolitic belt (NOB), 3- Cretaceous volcanic arcs terrane (KVA) ,4- Metamorphic southern sequences of passive paleomargin type (MSPP). The three last are tectonostratigraphic terranes. Three types of northern passive margin sections, with a distinct geographic pattern, are well developed: A- Guaniguanico sections, in western Cuba, with three subtypes: Sierra del Rosario, Sierra de los Organos and Cangre belt, B-North central Cuba sections, with a distinct stratigraphic and tectonic zonality. C- Maisí sections in easternmost Cuba, with low degree metamorphic rocks. In the three regions, the younger sequences, begining with the Upper Jurassic, are almost always carbonate rocks, meanwhile the lower part (Oxfordian or older) is terrigenous, except in northernmost central Cuba, where evaporites are present. A unconformity is present in sections in A and B, that could be correlated with the Mid-Cretaceous Sequence Boundary of the Gulf of Mexico and Florida Straits. Their similarities in stratigraphy and geologic history, along with their actual position, juxtaposed or very close to the Florida-Bahamas and Yucatan platforms of the North American plate, and their gradation to the Bahamas geology in northcentral Cuba, testifies that the NPP sections should be part of the passive Mesozoic margin of North America. The continuity in an eastern direction of Guaniguanico deep waters sections is shown in several outcrops, and many wells for oil exploration from western Havana province to Matanzas. Therefore, there are not reasons to consider the Mesozoic Guaniguanico sections as part of the "Southwestrn Tectonos-tratigraphic Terranes". Following this line of thought, if the Guaniguanico rocks belong to the same paleomargin where the oil and gas fieds of northern Havana and Matanzas provinces were generated, they are excellent prospects for the future search for hydrocarbons. [ABSTRACT FROM AUTHOR]