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The Garnet Line in Oxford County, Maine Pegmatites University of New Orleans ScholarWorks@UNO University of New Orleans Theses and Dissertations Dissertations and Theses Fall 12-18-2014 The Garnet Line in Oxford County, Maine Pegmatites. Myles Mathew Felch The University of New Orleans, [email protected] Myles M. Felch [email protected] Follow this and additional works at: https://scholarworks.uno.edu/td Part of the Geology Commons Recommended Citation Felch, Myles Mathew and Felch, Myles M., "The Garnet Line in Oxford County, Maine Pegmatites." (2014). University of New Orleans Theses and Dissertations. 1915. https://scholarworks.uno.edu/td/1915 This Thesis is protected by copyright and/or related rights. It has been brought to you by ScholarWorks@UNO with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights- holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/or on the work itself. This Thesis has been accepted for inclusion in University of New Orleans Theses and Dissertations by an authorized administrator of ScholarWorks@UNO. For more information, please contact [email protected]. The Garnet Line in Oxford County, Maine Pegmatites. A Thesis Submitted to the Graduate Faculty of the University of New Orleans in partial fulfillment of the requirements for the degree of Master of Science in Earth and Environmental Sciences By Myles Felch B.A., University of Maine at Farmington, 2012 December 2014 © 2014, Myles M. Felch ii Acknowledgments I would first like to thank Jim Nizamoff, whom I contacted a few years ago and eventually introduced me to the MP2 group. With that said, I would like to thank Al, Skip and Karen for allowing me to further my education here at the University of New Orleans. Of course this would also not be possible without the help of my officemates Drew, John, Karen, Kim, Leah, Mark and Sasha. I also need to thank all the Maine pegmatite miners who have given me access to their property over the past few summers and all other involved in their projects: Jeff Morrison, Gary Freeman, Ray Sprague, Frank Perham and company and Mary Groves and her crew at the Poland Mining Camp. I want to thank my professors at the University of Maine at Farmington, Dr. Eastler, Dr. Gibson and Dr. Reusch. You were the first people to show me the beauty that lies beneath my feet. Thank you for inspiring me. For all involved at the Maine and Mineral and Gem Museum, past and present. Thank you for everything you have given me. What I admire most about you all is the sense of family you all bring to this amazing project. Thank you for making me feel at home, you guys and gals are the best. Lauren El-Hajj, thank you for everything… and I mean everything. Seriously though, I would have never made it through this without you. I wish you the best, with love always. Sam and Gavin, you are the best brothers and friends anyone could ask for. You both mean the world to me, thank you for all your support. Ultimately this one goes out to my parents, without them this would not be possible. You both have given me everything; I am so lucky to have parents like you. Words cannot describe my love for you both. Hats off to you. iii Table of Contents List of Figures ..............................................................................................................................................v List of Tables ................................................................................................................................................ix Abstract ..........................................................................................................................................................xi Introduction .................................................................................................................................................1 Pegmatite Petrogenesis..............................................................................................................1 The “garnet line” ...........................................................................................................................3 Garnets in pegmatites .................................................................................................................5 Geologic Background ..................................................................................................................7 Quarry Descriptions ..................................................................................................................................10 Mt. Mica ............................................................................................................................................10 Mt. Apatite .......................................................................................................................................16 Pulsifer ................................................................................................................................17 The-Hole-In-The-Ground .............................................................................................20 The-Hole-In-The-Ground prospect ..........................................................................24 The Bennett ....................................................................................................................................24 The Havey ........................................................................................................................................25 The Tamminen ..............................................................................................................................27 The Emmons ...................................................................................................................................29 Methods .........................................................................................................................................................31 Scanning Electron Microscope (SEM) ..................................................................................32 Electron Microprobe (EMP) .....................................................................................................33 Directly Coupled Plasma Mass Spectrometry (DCP) ......................................................35 Textural Descriptions ...............................................................................................................................36 Mt. Mica ............................................................................................................................................36 Mt. Apatite .......................................................................................................................................47 The Bennett ....................................................................................................................................49 The Emmons ...................................................................................................................................49 The Havey ........................................................................................................................................50 The Tamminen ..............................................................................................................................52 Results ............................................................................................................................................................53 Discussion .....................................................................................................................................................83 Garnet Line Paragenesis ............................................................................................................83 Pollucite Occurrence ...................................................................................................................88 Rare-Earth Element Phosphates ............................................................................................90 Tourmaline Rims at Mt. Mica ...................................................................................................91 Localized Replacement Textures in the Garnet Line at Mt. Mica ...............................94 Conclusions ..................................................................................................................................................95 References ....................................................................................................................................................96 Appendix .......................................................................................................................................................103 Vita ...................................................................................................................................................................184 iv List of Figures Figure 1: Map showing locations of the five pegmatite quarries in this thesis. Modified after Wise and Brown 2010 and Tomascak et al. 2005. .........................................7 Figure 2: Partial pegmatite cross section highlighting the area beneath garnet line (footwall side) and core portion. Lepidolite (Lpd), cleavelandite (Clv), spodumene (Spd). Red dotted line marks garnet line. ................................................................12
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