The Rondonian-San Ignacio Province in the SW Amazonian Craton: An overview

The Rondonian-San Ignacio Province (1.56-1.30 Ga) is a composite orogen created through successive accretion of arcs, ocean basin closure and final oblique microcontinent-continent collision. The effects of the collision are well preserved mostly in the Paragua Terrane (Bolivia and Mato Grosso regions) and in the Alto Guapore Belt and the Rio Negro-Juruena Province (Rondonia region), considering that the province was affected by later collision-related deformation and metamorphism during the Sunsas Orogeny (1.25-1.00 Ga). The Rondonian-San Ignacio Province comprises: (1) the Jauru Terrane (1.78-1.42 Ga) that hosts Paleoproterozoic basement (1.78-1.72 Ga), and the Cachoeirinha (1.56-1.52 Ga) and the Santa Helena (1.48-1.42 Ga) accretionary orogens, both developed in an Andean-type magmatic arc; (2) the Paragua Terrane (1.74-1.32 Ga) that hosts pre-San Ignacio units (>1640 Ma: Chiquitania Gneiss Complex, San Ignacio Schist Group and Lomas Manechis Granulitic Complex) and the Pensamiento Granitoid Complex (1.37-1.34 Ga) developed in an Andean-type magmatic arc; (3) the Rio Alegre Terrane (1.51-1.38 Ga) that includes units generated in a mid-ocean ridge and an intra-oceanic magmatic arc environments; and (4) the Alto Guapore Belt (<1.42-1.34 Ga) that hosts units developed in passive marginal basin and intra-oceanic arc settings. The collisional stage (1.34-1.32 Ga) is characterized by deformation, high-grade metamorphism, and partial melting during the metamorphic peak, which affected primarily the Chiquitania Gneiss Complex and Lomas Manechis Granulitic Complex in the Paragua Terrane, and the Colorado Complex and the Nova Mamore Metamorphic Suite in the Alto Guapore Belt. The Paragua Block is here considered as a crustal fragment probably displaced from its Rio Negro-Juruena crustal counterpart between 1.50 and 1.40 Ga. This period is characterized by extensive A-type and intra-plate granite magmatism represented by the Rio Crespo Intrusive Suite (ca. 1.50 Ga), Santo Antonio Intrusive Suite (1.40-1.36 Ga), and the Teotonio Intrusive Suite (1.38 Ga). Magmatism of these types also occur at the end of the Rondonian-San Ignacio Orogeny, and are represented by the Alto Candeias Intrusive Suite (1.34-1.36 Ga), and the Sao Lourenco-Caripunas Intrusive Suite (1.31-1.30 Ga). The cratonization of the province occurred between 1.30 and 1.25 Ga. (C) 2009 Elsevier Ltd. All rights reserved.

Ignacio de Assis Silva e os estudos literários

This paper aims to honor the semiotician Ignacio Assis Silva printed by the intensity in all his activities, emphasizing mainly on the accuracy insightful essays, which made him not only one of the most important promoters of semiotics greimasian in Brazil, but one of those responsible for its development. It should be noted also that he served with dedication in the Postgraduate Program in Literary Studies FCL/Araraquara UNESP, including efforts since its founding. The program owes much to him and others of FCL semioticians for the healthy integration between programs, Linguistics/Portuguese Language and Literary Studies. The latter was even initially, a literature program focusing on semiotics greimasian. Join together with all his persistent interest in building a "theory of language", which deeply and tenaciously pursued in their classes and in their texts and can be detected in Figurativização e metamorfose: o mito de Narciso (1995).

Metamorfose: reflexões sobre o pensamento de Ignacio Assis Silva ou tentando achar o fio da meada

This text, homage to Ignacio Assis Silva, looks for the founding theoretical conceptions of his thoughts. When I looked at his texts, from the 70’s to the 90’s, my reading went through the path of an author who is always worried about revealing the birthplace of meaning. To catch this unique moment of semiosis, Silva proposes the concept of metamorphosis, a key-term which allows us to unite the two ends of his formation: Historical Grammar and Semiotic