Petrology and tectonics of the Cordillera

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The mountain belt located along the western edge of North and South America, commonly referred to as the Cordillera, was formed by Earth processes dating back to the Precambrian (older than 550 million years) and continuing to the present day. In the modern environment, these processes are manifested by earthquakes, volcanoes, and the current pattern of geological features. Those that occurred in ancient times are recorded by older rock formations that can be examined in the field and laboratory to interpret the nature, age and sequence of events. This proposal seeks to understand two aspects of Cordilleran geology, one of which refers to modern and geologically recent times, and the other to more ancient times in the Precambrian. The study of modern processes will examine rocks, other geological features, and geophysical characteristics at locations where two tectonic plates located beneath the Pacific ocean are moving apart from one another, and one or both of them is subducting (being pulled beneath) the plates that make up the Americas. The process involved, termed ridge subduction, is occurring at four localities at the present time, including beneath western Canada. Studying the earthquakes, volcanoes and other features that form in these locations will clarify the mechanisms and outcomes of ridge subduction. The study of Precambrian rocks will be carried out on formations in the Yukon and northern British Columbia. The goal is to decipher the ancient geological environment and determine the most likely configuration of the continents the Precambrian. Both the Precambrian and modern investigations involve petrology (the study of rocks, their features and their compositions) and tectonics (the study of Earth structures and movements). The methods to be used in these studies include geological mapping, rock and mineral examination, determination of geochemical compositions and isotopic ages, plus geographical information system (GIS) technology.