University at Albany, State University of New York Scholars Archive Geology Theses and Dissertations Atmospheric and Environmental Sciences 1999 The geology of the Liberty-Orrington-Passagassawakeag/ Fredericton Trough terrane boundary in the Bucksport-Orland area, coastal Maine Heather A. Short University at Albany, State University of New York Follow this and additional works at: https://scholarsarchive.library.albany.edu/cas_daes_geology_etd Part of the Geology Commons, and the Tectonics and Structure Commons Recommended Citation Short, Heather A., "The geology of the Liberty-Orrington-Passagassawakeag/Fredericton Trough terrane boundary in the Bucksport-Orland area, coastal Maine" (1999). Geology Theses and Dissertations. 84. https://scholarsarchive.library.albany.edu/cas_daes_geology_etd/84 This Thesis is brought to you for free and open access by the Atmospheric and Environmental Sciences at Scholars Archive. It has been accepted for inclusion in Geology Theses and Dissertations by an authorized administrator of Scholars Archive. For more information, please contact
[email protected]. ABSTRACT The Liberty-Orrington fault separates two tectonic terranes of widely different lithologies and metamorphic grades within the Coastal Lithotectonic Belt of Maine. While the juxtaposition of the sillimanite-bearing Passagassawakeag gneiss and the chlorite grade Bucksport Formation (turbidites) requires a fault between them, field evidence for, and an understanding of, the nature of the fault has hitherto been lacking. Although the Liberty-Orrington fault has previously been interpreted as a thrust, strike- slip, and/or normal fault, the most recent debate has been centered around two models of Acadian amalgamation involving thrusting of the Passagassawakeag terrane from the southeast vs. thrusting from beneath central Maine (from the northwest) (Osberg et al., 1998; Stewart et al., 1995).