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Showing papers by "Universidad del Norte, Colombia published in 1977"


Journal ArticleDOI
TL;DR: A geological scheme of the Domeyko Range of Northern Chile is described in this paper, which consists of a basement formed by granitic, volcanic, and marine sedimentary rocks, and by Triassic acidic volcanics with continental intercalations.
Abstract: This work describes a geological scheme of the pre- And ean Domeyko Range of Northern Chile. This pre- And ean area consists of a basement formed by Paleozoic granitic, volcanic, and marine sedimentary rocks, and by Triassic acidic volcanics with continental intercalations. The Andean Basin developed in the Lias over the basement, with initial stages that include volcanic and continental sequences. A continuous marine environment existed in the Hettangian-Tithonian span, with volcanic events in the Bajocian, Callovian, Kimmeridgian, and Tithonian. Evaporitic facies developed in the Oxfordian-Kirnmeridgian. A marine-continental basin is recognized in the Neocomian, the Upper Cretaceous being represented by volcanic and continental deposits, a development similar to the Tertiary one; over these sequences volcanic, detrital, and saline deposits were laid down in the Plio-Pleistocene. Compressional tectonic cycles developed in the Upper Paleozoic, Upper Lias?, Upper Jurassic, Upper Cretaceous, and Tertiary, and tensional phases occured in the Triassic, Cretaceous, and Tertiary. The compressional stages were characterized by intrusive cycles while the tensional phases witnessed volcanic sedimentary events.

33 citations


Journal ArticleDOI
TL;DR: In this article, the authors considered the problem of finding a pair of continuous functions f and g such that f(x) + g(y) ⩾ K(x, y) on I × I and ∝I (f + g) is minimum.

1 citations