A mineralogical analysis of pillow basalts to determine subglacial magmatic processes in Undirlithar quarry, Reykjanes Peninsula, Iceland

A mineralogical analysis of pillow basalts to determine subglacial magmatic processes in Undirhlíðar quarry, Reykjanes Peninsula, Iceland Sources: http://mapsof.net/iceland/static-maps/png/volcanic-system-of-iceland-map-fr http://culturedecoded.wordpress.com/2008/08/05/the-truth-about-our-media/world-map-without-dots/ http://en.wikipedia.org/wiki/File:Subglacial_Eruption-numbers.svg http://serc.carleton.edu/research_education/geochemsheets/wds.html http://serc.carleton.edu/research_education/geochemsheets/techniques/EPMA.html http://serc.carleton.edu/research_education/geochemsheets/techniques/SEM.html Jakobsson, S.P., Jonsson, J., and Shido, F., 1977, Petrology of the Western Reykjanes Peninsula, Iceland: Journal of Petrology, v. 19, p.669-705. Previous Work: Todd Spillman '10~ Collected samples and made thin sections from East, South and West quarry walls Concluded that lava viscosity and pillow size are not correlated Future Work: Take thin sections to the SEM at Oberlin to identify particular crystals we want to target with the EPMA Collect more samples from Iceland Take thin sections to the EPMA and acquire data Synthesize what I've learned and what Becky Alcorn '11 concluded in order to make a well-researched statement about magmatic processes Becky Alcorn '11~ Collected samples and made thin sections from South quarry wall Field Results: Observations of the quarry walls indicated 3 different eruptive events and 2 different intrusive events Mineralogical Results: 3 different magma types Chemical Results: 2 different magmas, high MgO, low La/Sm and low MgO, high La/sm ratios Mineralogical and chemical results Concluded that a single parent magma model coudn't explain the data, must be more than one lava source Intrusions with olivine Intrusions without olivine Extrusions Dike 1 Dike 2 Sheet Dike 3 Upper pillows Middle Pillows Lower Pillows Knob Pillows Mineralogy Chemistry High MgO/ Low La/Sm Low MgO/ High La/sm By Lindsey J. Bowman Mined for aggregate, construction filler, now being reclaimed as a park .2 km S-10-11, Dike 2, Intrusion with olivine S-10-15, middle pillows, extrusion S-10-21, Dike 3, Intrusion without olivine UND-E-01, East wall UND-W-01, West wall