Decompression during Late Proterozoic Al2SiO5 Triple-Point Metamorphism at Cerro Colorado, New Mexico

An outstanding problem in understanding the late Proterozoic tectonic assembly of the southwest is identifying the tectonic setting associated with regional metamorphism at 1.4 Ga. Both isobaric heating and cooling, and counter-clockwise looping PT paths are proposed for this time. We present a study of the Proterozoic metamorphic and deformation history of the Cerro Colorado area, southern Tusas Mountains, New Mexico, which shows that the metamorphism in this area records near-isothermal decompression from 6 to 4 kbar at ca. 1.4 Ga. We do not see evidence for isobaric heating at this time. Decompression from peak pressures is recorded by the reaction Ms + Grt = St + Bt, with a negative slope in PT space; the reaction Ms + Grt = Sil + Bt, which is nearly horizontal in PT space; and partial to total pseudomorphing of kyanite by sillimanite during the main phase of deformation. The clearest reaction texture indicating decompression near peak metamorphic temperature is the replacement of garnet by clots of sillimanite, which are surrounded by halos of biotite. The sillimanite clots, most without relict garnet in the cores and with highly variable aspect ratios, are aligned. They define a lineation that formed with the dominant foliation. An inverted metamorphic gradient is locally defined by sillimanite-garnet schists (625 degrees C) structurally above staurolite-garnet schists (550 degrees C) and implies ductile thrusting during the main phase of deformation. The exhumation that led to the recorded decompression was likely in response to crustal thickening due to ductile thrusting and subsequent denudation.

Casualty, Causality and Chivalry: the Myth of Chivalry and Racial Violence in Southern Literature

This honors thesis project uses history and literature to analyze the role of the myth of chivalry in mystifying racial violence and oppression in the American South. The central claim is that the myth of chivalry¿ and particularly the exaltation of the white woman¿ is a myth system used to justify racial violence, oppress white womanhood, and allow white patriarchy to maintain political, social and economic dominance. This project traces the role of literature, especially Sir Walter Scott¿s historical romance, in developing the foundational myths of a southern society based in violence, racial hierarchy and gender inequality. It then follows the role of white womanhood in this myth¿ the restrictions on miscegenation, the exaltation of pure white femininity, and the violent actions performed in the name of southern women. With this historical baseline established, this study then explores three works of historical fiction that attempt to subvert this mythology by critiquing and demystifying the myth of chivalry, while also offering counter-narratives to popularized history. These works are Charles Chesnutt¿s 1901 novel The Marrow of Tradition¬, which analyzes the 1898 Wilmington N.C. race riot, Gwendolyn Brooks¿ 1960 poem ¿A Bronzeville Mother Loiters in Mississippi. Meanwhile, a Mississippi Mother Burns Bacon¿ and Lewis Nordan¿s 1993 novel Wolf Whistle, two works about Emmett Till¿s tragic murder in 1955. This study, then, illuminates the intersection of literature and mythology, revealing how literature is useful for both creating and subverting myth¿and revealing how authors undertake this task.