Collaborative Research: Chemical Equilibria Involving Iron and Hydrogen in Metapelites From Western Maine

The primary goal of this research is to evaluate the chemical equilibria involving ferrous and ferric iron and hydrogen in metapelitic rocks from western Maine and related rocks at Black Mountain, New Hampshire. We will study samples from graphite, magnetite, and hematite-bearing rocks at three different metamorphic grades: garnet, lower sillimanite, and staurolite zone. This will permit the determination of: (1) in situ partition coefficients for Fe3+ and Fe2+ among all the Fe-bearing phases and for H among hydrous phases;(2) the temperature and fO2 dependence of Fe3+/Fetotal and effects of Fe3+ substitution on other cation substitutions plus their implications for geothermometry; and (3) the cation substitutions that charge balance variations of H and Fe3+. We will also characterize and seek to understand Fe3+/Fetotal zoning within individual mineral grains as well as variation of Fe3+/Fetotal among grains of the same mineral in the same rock; ultimately, we will assess the effects of assemblage on Fe3+/Fetotal in the constituent mineral phases present. These measurements will be made on standard 1 round petrographic thin sections using beam sizes of less than 10 x 15 micrometers and the relatively rapid, non-destructive techniques of synchrotron microXANES spectroscopy (SmX) for Fe3+/Fetotal, ion microprobe (SIMS) for H, and the electron microprobe (EPMA) for other major elements. With our analytical results in hand, we can begin to address the competing effects of assemblage and crystal chemistry on the incorporation of Fe2+ and Fe3+ in metapelite minerals. We also hope to effectively and quickly demonstrate the potential importance of SmX as a petrologic tool

Metamorphic Petrology, Mineralogy and Polymetamorphism in a Portion of N.W. Maine

Guidebook for field trips in the Rangeley Lakes - Dead River Basin region, western Maine: 62nd annual meeting October 2, 3, and 4, 1970: Trip B-

MRI: Acquisition Of A Modern Electron Microprobe At The University of Maine

This award, made through the Major Research Instrumentation (MRI) Program, provides support for the acquisition of a state-of-the-art electron microprobe (EMP) for the microchemical characterization of geological materials. A new EMP will replace an aging (vintage 1981) ARL SEMQ in the Department of Geological Sciences at the University of Maine. The instrument will facilitate research on a range of topics in metamorphic petrology including, the speciation of Fe and distribution of OH- in metapelites, and light element (i.e. Li, B, Be) partitioning in granulite facies rocks. Research in paleoclimatology will also be enhanced by this instrument. The probe will be used to analyze volcanic glass shards in ice core samples for trace and major element compositions. Coupled with analyses of suspected source tephras, such chemical analyses offer the strong possibility of verifying the provenance of ice core tephra and therefore relating these discrete events to climate proxies also recorded simultaneously in ice cores. This facility will be the only modern EMP in the state of Maine and will serve not only the needs of faculty and students from several departments at the University of Maine , but also the needs of faculty and students from nearby regional institutions (i.e. Bowdoin, Univ. of Southern Maine, Bates)

The Geology of the Camden-Rockland Area

Guidebook for field trips in east-central and north-central Maine: 66th annual meeting October 12 and 13, 1974: Trip A-

Acquisition of an Automated Powder X-Ray Diffraction System

This grant provides $70,295 as one-half support of the costs of acquiring a state-of-the-art powder X-ray diffractometer (XRD) that will be housed in a newly constructed Global Sciences building on the Orono campus of the University of Maine. This acquisition will allow these PI\u27s to continue their internationally recognized research programs in petrologic mineralogy including studies of the phase equilibria of solid solutions in metamorphic rocks and borosilicates. The characterization of both structural properties and mineralogic identification of unknowns is fundamental to these researchers and the establishment of a modern XRD facility at the University of Maine will benefit a number of other faculty both within the Department of Geological Sciences and within the departments of Physics and Engineering

Geology of the Lower Paleozoic Rocks in the Boundary Mountain Anticlinorium

Guidebook for field trips in the Rangeley Lakes - Dead River Basin region, western Maine: 62nd annual meeting October 2, 3, and 4, 1970: Trip A-

The Norumbega Fault Zone, Maine: a mid-to shallow-level crustal section within a transcurrent shear zone

From studies of structure, metamorphism, and geochronology we have evidence that the Norumbega Fault Zone represents a transition from mid- to shallow crustal levels in a dextral, transcurrent shear zone within the northern Appalachian Orogen. The Norumbega Fault Zone strikes parallel to the orogen (northeast-southwest), is ~5 to 30 km wide, and is characterized by distributed ductile dextral shear fabrics in the southwestern section with a transition to brittle fabrics toward the northeast. Within the zone of distributed shear, deformation is partitioned into local zones of very high strain. Upright, isoclinal folds are common in areas of high and low strain. Metamorphic grade decreases from amphibolite facies in the southwest to sub-green schist facies in the northeast. 40Ar/39Ar mineral ages from recrystallized minerals in a high strain zone, regional cooling ages in areas of lower strain, and metamorphic textures are consistent with a polyphase history of deformation. We interpret a younging trend in 40Ar/39Ar cooling ages toward the northeast, together with the deformational fabrics andmetamorphic features, to represent exhumation of the southwestern section of the Norumbega Fault Zone from mid-crustal levels during the polyphase history of this transcurrent zone. The Norumbega Fault Zone may therefore serve as a model for deformational processes at mid- to shallow crustal levels in active strike-slip systems. RÉSUMÉ Des études de la structure, du métamorphisme et de la géochronologic nous fournissent la preuve que la zone faillée de Norumbega représente une transition des niveaux crustaux moyens à des niveaux peu profonds dans une zone de cisaillement transversal dextrale à l'intérieur de la partie septentrionale de l'orogene appalachien. La zone faillée de Norumbega suit une direction paralléle a l'orogéne (nord-est-sud-ouest); die a cinq à 30 km de largeur; et elle est caractérisec par des structures cisaillées dextrales déformables se ramifiant dans la section sud-ouest avec une transition a des structures cassantes vers le nord-est. A l'intérieur de la zone de cisaillement ramifié, la déformation est divisée en zones locales de très forte contrainte. Les plis droits isoclinaux sont courants dans les secteurs de forte et faible contrainte. L'intensité du métamorphisme décroit d'un faciès à amphibolite dans le sud-ouest à un faciès secondaire de schistes verts dans le nord-est. Les périodes minérales 40Ar/39Ar des minéraux recristallises dans une zone de forte contrainte, les périodes de refroidissement régional dans les secteurs de faible contrainte et les textures métamorphiques correspondent à une orogénese polyphasée. Nous interprétons la tendance de rajeunissement dans les périodes de refroidissement 40Ar/39Ar vers le nord-est, de même que les textures de déformation et les caractéristiqucs métamorphiques, comme une exhumation de la section sud-ouest de la zone faillée de Norumbega depuis les niveaux crustaux moyens pendant l'histoire polyphasée de cette zone transversale. La zone faillée de Norumbega pourrait, par consequent, servir de modèle pour les processus de déformation aux niveaux variant de moyens à peu profonds dans les systèmes a décrochement. [Traduit par la rédaction

A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial

Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services

Geology of the Bryant Pond quadrangle, Maine

Maine Geological Survey (Department of Economic Development), Bulletin 16 (Quadrangle Mapping Series 3)https://digitalmaine.com/mgs_maps/1078/thumbnail.jp

Geology of the Bryant Pond quadrangle, Maine

Maine Geological Survey (Department of Economic Development), Bulletin 16 (Quadrangle Mapping Series 3)https://digitalmaine.com/mgs_maps/1078/thumbnail.jp