Physical Sciences and Mathematics Commons^™

Petrology And Thermodynamic Modeling Of Amphibolite Facies Rocks Of The Blåhø Nappe Of The Middle Allochthon, Scandinavian Caledonides In Norway, Maria Van Nostrand

Honors Theses

The Scandinavian Caledonides are an orogenic belt formed when Baltica collided with Laurentia during the late Silurian to early Devonian (Scandian, ~426–390 Ma, Gee et al., 2008). The thrust sheets forming the belt are divided into the Lower, Middle, Upper, and Uppermost Allochthons derived, respectively, from the Baltican margin and regions progressively farther outboard. This study focuses on the Blåhø Nappe, part of the Middle Allochthon, which is generally presumed to have been from an Early Paleozoic volcanic arc off the Baltican margin. The Blåhø Nappe contains abundant igneous and sedimentary rocks, metamorphosed almost entirely at amphibolite facies, but contains …

Thermobarometric Modeling Of The Catalina Amphibolite Unit: Implications For Tectonic And Metasomatic Models, Henry W. Towbin

Honors Papers

On Santa Catalina Island, Ca high-grade amphibolite units overlie progressively lower- grade blueschist units in an inverted stack structure. This juxtaposition of high grade and low-grade metamorphic units has long been the subject of much debate as to the tectonic origins of the formation and how it relates to California's tectonic evolution. Previous petrography and thermobaromety of blocks in the amphibolite unit estimate pressures and temperatures of ~8-11 kbar and ~640-750 °C (Platt, 1975; Sorensen and Barton 1987). These estimates were calculated before many of the computational advances in modern thermobarometry. Using Equilibrium Assemblage Diagrams (EAD) calculated with Theriak Domino, …

Geochemical Systematics Among Amphibolitic Rocks In The Central Blue Ridge Province Of Southwestern North Carolina, Nathan Collins

USF Tampa Graduate Theses and Dissertations

The Central Blue Ridge sub-province of the southern Appalachian Mountains preserves an unique and complex geologic history. The Cartoogechaye terrane is the westernmost terrane of the Central Blue Ridge sub-province, and is characterized by extensive olistostromal sequences, including mafic-ultramafic massifs, isolated mafic units, and block-in-matrix structures of varying scales. This study investigates the genetic and tectonic relationships, and regional chemical and metamorphic trends of the amphibolitic rocks entrained within units of the Cartoogechaye and nearby terranes, toward constraining the origins of these regional sequences, and examining the rationale for the current Blue Ridge terrane designations.

A distinct compositional variation exists …