Phanerozoic evolution of the North American Cordillera; United States and Canada

Abstract

The rediscovery of America by the Genovese Christopher Columbus and the conquest of Mexico by the Spaniards was followed by a more gradual, but equally relentless, occupation of North America by the French and the British. The last phase of this process involved the discovery and exploration of the western Cordillera of North America. Fur traders Anthony Henday (1754) and the La Verendrye brothers (1743) were the first non Indians to sight the western Cordillera, while James Cook (1778) and Vitus Bering (1728,1741) were the first to explore the coasts of the northern Pacific beyond a California that was already discovered and subdued by the Spanish. There followed many expeditions that were driven by the search for gold and the fur trade as well as political and missionary interests. Most spectacular perhaps was the first crossing of the Canadian Cordillera by the Scot, Alexander MacKenzie, who reached the Pacific near Bella Coola, British Columbia in 1793. In his footsteps, the expeditions of Simon Fraser (1807), David Thompson (1807–1812), and others led to the geographic reconnaissance of the Cordillera of the northwestern United States and Canada. Lewis and Clark (1804–1805), who traversed the northwestern U.S. Cordillera, were the first who, while obviously involved in a politically motivated expedition, had an important charge to also make scientific observations. Thus, the western Cordillera had first to be “discovered” through the arduous efforts of many early explorers before any significant geological studies could be undertaken. The first geological map of North America, published by Jean Etienne Guettard in 1752 in his “Mémoire dans lequel on compare le Canada à la Suisse,”

Thick-Skinned and Thin-Skinned Tectonics: A Global Perspective

“…The accretion of terranes in Late Jurassic -Early Cretaceous times involved the delamination of the docking microplates: only the crustal sections were accreted as "orogenic float", while the lithospheric mantle part was subducted [223]. This deformation style is in concert with thick-skinned tectonics.…”

“…The North American Cordillera evolved from a complex set of processes that involved subduction, the accretion of terranes and strike-slip faulting in mainly Mesozoic -Cenozoic times [223][224][225]. Three transects are presented here which together yield a comprehensive view of the thick-and thin-skinned tectonic styles encountered in this orogen.…”

“…Here too, stresses must have been transmitted by a strong upper crust for much of this distance. Figure 24A Cross-section of the North American Cordillera in southern Canada based on [223], LITHOPROBE [229][230][231] and [228]. Inset: Thick-skinned and thin-skinned tectonics in the Omineca Belt.…”

Simulating the evolution of the Asian and African monsoons during the past 30 Myr using an atmospheric general circulation model

“…We prescribe for this mountain belt, a low mean altitude (less than 1000 m) at the Oligocene [Bird, 1988] (Figure la), remnant of the Laramide orogeny (75-45 Ma). The tectonic evolution of the western continental part was driven by the subduction of the Pacific plates during the Cenozoic [Oldow et al, 1989]. The segmentation of this subduction zone has induced a transition from compressive to extensive regimes in western America.…”

Systhesis of Volcanism Studies for the Yucca Mountain Site Characterization Project

“…Noteworthy papers that describe important properties of the Basin and Range province with emphasis on the central Basin and Range subprovince include Nolan (1943), S'hawe (1 965), Hamilton and Myers (1 966), Armstrong et al (1969), Atwater (I 970), Anderson (1 97 I), Scholz et al (1 97 l), Stewart (1 97 I), , Christiansen and Lipman (1 972), Noble (1972), Kistler and Peterman, (1973), Best and Brirnhall(1974), Thompson (1974), Smith and Sbar (1974), Wright et al (1974), Snyder et al (1976), Wright (1976), Proffett (1977), , Best and Hamblin (1978), Christiansen and McKee (1978), , Lachenbruch and Sass (1978), Smith (1978), Stewart (1978), Zoback and Thompson (1978), Eaton (1979), Eaton (1980), Lipman (1980), Stewart (1980), Guth (1981), Wernicke (l981), Zoback et al (1 98 I), Armstrong (1 982), Eaton (1 982), Hill (1 982), Glamer and Supplee (1 982), , Wernicke and Burchfiel(1982), Coney and Harms (1984), Farmer and DePaolo (1983;, , Hudson and Geissman (1987), Hamilton (1988), Snoke and Miller (1988), Wernicke et al (1988), Farmer et a1.,(1989), Gans et al (1989), Oldow et al (1989), , Hodges and Walker (1990), McKenna and Hodges (1990), , , Armstong and Ward (1991), Walker and Colman (1991), , …”