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Erin
Doak Dr. Tom Simkin, Ph.D.
"Ten weeks cannot contain
the vast amount of knowledge or the quality friendships that I have
gained through this experience; I will be benefitting from the RTP
for the rest of my career." |
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Roots
of an Ancient Volcano: The
Isle of Skye is located in northwest Scotland and is associated with
the volcanic activity that transpired during the opening of the Atlantic
Ocean, approximately 58 million years ago. The intricate igneous complex
on Skye has long challenged geologists and still defies a comprehensive
explanation of all its features. Dikes, thin vertical intrusions that
slice through pre-existing rock, are very numerous on the island and
many were the conduits which fed ancient lava flows. A few of these
dikes contain an extraordinary amount of olivine, the unfinished version
of the gemstone peridot. These minor intrusions are found scattered
throughout the island and have been divided into three groups based
on previous research and their geographic locations. The purpose of
this research was to analyze the olivines found in the picrite (olivine-rich)
dikes of Northern Skye to determine their homogeneity and then compare
these results to data from the other two groups in order to ascertain
co-genetic links. Chemical compositions of olivine cores were attained
with the aid of an electron microprobe, an instrument that measures
characteristic x-rays emitted from a mineral upon bombardment of electrons
from a high-intensity beam. The data showed very little variation
and it appears that these intrusions are a part of the same series.
Olivine cores from picrite dikes in Southern Skye also showed a striking
similarity, both in the make up of the rock and the chemical composition
of their olivines. It appears that similar origin and time of emplacement
relate these two groups. By comparing the chemical composition of
olivines, scientists can learn more about the ‘plumbing’
of volcanic complexes and the factors that influence their development.
This research was supported by a grant from the National Science Foundation Research Experiences for Undergraduates program, Award Number DBI 9820303. |