The Precambrian rocks in western Ethiopia consist of highand low-grade terranes intruded by granitoids with a wide compositional spectrum. The formation ages of these granitoid rocks are, so far, poorly understood. Single-grain zircon Pb/Pb evaporation and conventional U/Pb dating conducted on four granitoids places time constraints on their emplacement and tectonothermal events. Three granitoi...

Title of Document: The Multiple Sulfur Isotopic Composition of Iron Meteorites: Implications for Nebular Evolution. Michael Ariel Antonelli, Master of Science, 2013. Directed By: Professor James Farquhar, Department of Geology and Earth System Sciences Interdisciplinary Center, University of MarylandCollege Park Multiple sulfur isotopic measurements of troilite from 61 different iron meteorites...

[1] Floor-Fractured Craters (FFCs) are a class of lunar craters characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures; additional interior features are moats, ridges, and patches of mare material. Two formation mechanisms have been hypothesized—floor uplift in response to shallow magmatic intrusion and sill formation, and floor shallowing in response ...

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A tephrostratigraphy of the active Antarctic volcano, Mt. Erebus, was determined from englacial tephra on the ice-covered flanks of Erebus and an adjacent volcano. The tephra are, used to reconstruct the eruptive history and magmatic evolution of Erebus. Scanning electron microscope images and Image Particle Analysis suggest the tephra formed in phreatomagmatic and magmatic eruptions and in som...

Porphyry deposits, our main source of copper and of significant amounts of Mo, Re and Au, form at convergent margins in association with intermediate-felsic magmas. Although it is accepted that copper is transported and precipitated by fluids released by these magmas, the magmatic processes leading to the formation of economic deposits remain elusive. Here we perform Monte Carlo petrological an...

The Hezar Igneous Complex (HIC) in the south-eastern part of Urumieh-Dokhtar magmatic arc, is the most prominent magmatic feature in the Kerman Porphyry Copper Belt, that understanding magmatic evolution of which may shed light on the tectonomagmatic development of this less-studied part of an important magmatic arc in the Neotethys realm. The HIC has been developed in the the intersection of t...

Eruption forecasting is a major goal in volcanology. Logically, but unfortunately, forecasting hazards related to non-magmatic unrest is too often overshadowed by eruption forecasting, although many volcanoes often pass through states of non-eruptive and non-magmatic unrest for various and prolonged periods of time. Volcanic hazards related to non-magmatic unrest can be highly violent and/or de...