Geological Overview
Ecuador is located along the spine of the Andean Cordillera and is divided into three geomorphic and geologic provinces: the Costa, the Sierra and the Oriente.
The Costa is an accreted region along the Pacific margin and comprises Upper Cretaceous to Cenozoic fore-arc sedimentary basins. The basement rocks are Lower Cretaceous marine basalts and basaltic andesites.
The Sierra is a young, active mountain belt formed by at least two orogenic events: the Cordillera Occidental to the west of Paleozoic age and the Cordillera Real to the east of late Mesozoic to Cenozoic in age. The Cordillera Occidental contains remnants of a Cretaceous island arc overlain by Lower Tertiary volcanic and volcaniclastic rocks. A series of Tertiary intrusions are found along the western flank of this cordillera. Active volcanoes of Pliocene/Pleistocene age occur along the western and eastern flanks of both the western Cordillera Occidental and the eastern Cordillera Real.
The Inter-Andean Valley separates the Cordillera Occidental from the Cordillera Real. The Cordillera Real is composed of metamorphic rocks and composite calc-alkaline batholiths of Triassic to Tertiary age. The Oriente consists of a series of Cretaceous back-arc sedimentary basins occurring as flat-lying sequences in the Amazon Basin. This region is almost completely covered by vegetation. Jurassic to Tertiary volcanic rocks occur along the western margins of the Oriente. Tertiary rocks cap all the Cretaceous structures.
There is potential in Ecuador for the discovery of a variety of mineral occurrences. These include volcanogenic massive sulphide (VMS), base metal, porphyry copper, epithermal and mesothermal gold, and skarn base metal and gold deposits.
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Ecuador Overview
Geological Overview
