Geology Faculty Research

Click on the individual names below for faculty websites, research interests, publications and contact information

 

Early Mount St. Helens Volcanic History

Most previous work and research done concerning the eruptive stages of Mount St. Helens (MSH), Washington focuses on the more recent eruptive period, the Spirit Lake Stage. There is a lack of information on the older eruptive stages including the Ape Canyon eruptive stage (300 to 35 ka), the Cougar eruptive stage (28-18 ka), and the Swift Creek eruptive stage (16-12.8 ka). This is problematic given the complexity of MSH. The main objective of this study is to obtain a better understanding of the magmatic processes that took place during the early history of MSH. These samples are being examined by electron microprobe (EPMA) and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) to determine the chemistry of the minerals and the melt inclusions. Researchers: Will Bradford, Kevin Gryger, Dr. Rocky Severs, Associate Professor of Geology.


Investigating the Origins of Adakites

Adakites are unusual volcanic rocks whose origin is not entirely clear. Senso stricto, adakites have geochemical characteristics that have typically been attributed to be generated by melting of subducted ocean crust. Adakites are important because they are often considered analogues of the tonalite-trondhjemite-granodiorite (TTG) suite plutonic igneous rocks that make up a significant portion of the Archean continental crust. Recent evidence suggests that adakites may represent complex mixtures that may have a continental crust component as well changing the model for how early continental crust formed. This study focuses on investigating adakites that were defined from Mount St. Helens, Washington. This project is aimed at examining the mineral chemistry and geochemistry of melt inclusions using the EPMA and LA-ICPMS to better understand how these adakites are formed. Researchers: Will Bradford, Kevin Gryger, Dr. Rocky Severs, Associate Professor of Geology.


Understanding Adirondack Garnet Formation

Garnets from the Adirondacks in upstate New York have been used economically over the past 125 years for their extreme hardness. They are also famous for because of their abnormally large size. The garnets are typically found in two different rock types: meta-gabbros and meta-anorthosites. Debate lingers whether these garnets are growing exclusively by metamorphic processes or also from partial melts. Four main areas that produce these garnets of interest include Gore Mountain, Warrensburg, Ruby Mountain and the Old Hooper Mine. The focus of this study is to better understand the growth and generation of garnets in different rock types by examining their geochemistry using the EPMA and LA-ICPMS and by experiments on the polyphase mineral inclusions found inside the garnets. Researchers: Steven Booty, Matt Remuzzi, T.J. Sarnoski Jr., Dr. Rocky Severs, Associate Professor of Geology.


Crystal Size Variation in Byram Diabase (NJ)

The Byram (NJ) diabase mafic igneous intrusion is a Jurassic-age unit associated with the failed continental rifting found in the Newark Basin. It is fault-bounded by shales of the Lockatong Formation. Hand samples from the Byram diabase appear to have significant differences in the crystal sizes over the span of 500 meters or less. Samples were collected from the diabase in February 2011 in order to determine whether there is a quantitative difference in grain size. Samples are currently being made into thin sections and will be analyzed by crystal size distribution (CSD) image analyses to make such a determination. CSD analyses will also provide constraints on the crystal growth rates and nucleation rates of the diabase. Researchers: Sarah Justus, Dr. Rocky Severs, Associate Professor of Geology


Geochemistry of Modern and Ancient Florida Reefs

My research in Florida involves comparative geochemical analysis (Rare Earth Element (REE) signatures) between the classic Florida Pleistocene deposits of the Anastasia formation, Miami Limestone and the Key Largo Limestone and similar modern reef tract environments. The research entails comparative analysis of REE analysis for the purposes of fossil provenance, the fossilization process, stratigraphy, and paleoenvironmental interpretations. Other research entails modern coastal processes and modeling of the Florida Coastlines, Florida Bay and the Florida Keys. Researchers:  Suzanne Reiley