|
|
Conducting high-temperature and pressure experiments allows us to simulate the conditions and processes that occur in a magma chamber. I use experimental petrology in my research to recreate tiny magma chambers in order to examine elemental behavior at magmatic conditions that leave chemical fingerprints on the mineral and rock record.
|
|
Diffusion chronometry (also known as geospeedometry) has become a popular tool for determining the tempo of magmatic processes. It is especially important to use multiple chronometers in a single phase for differentiating magmatic processes from one another (e.g., Shamloo and Till 2019). Current research uses a 1-atm vertical furnace to determine how and how fast magnesium diffuses in alkali-feldspar, a ubiquitous phase in silicic volcanic rocks. Results suggest Mg diffuses simultaneously by both a fast- and slow-mode, suggesting diffusion in feldspar is more complex than previously understood (Shamloo et al. 2021).
|
Simple schematic of the experimental design for diffusion experiments (Shamloo et al. 2021).
|
Cold-seal pressure vessel apparatus in Jim Watkins Experimental Lab at University of Oregon.
|
|
Ba zoning in sanidine is commonly observed and is used to make interpretations on the processes and timescales associated with magma storage and eruption. However, little is known on what actually controls Ba (and other trace element) zoning (i.e., partitioning) in sanidine, leaving it unclear on what Ba zoning in sanidine is really recording. My work explores these controls by conducting cold-seal pressure vessel experiments as well as Laser ICP-MS analysis of both natural and experimental sanidine and rhyolites. Pictured on the top right is a precious metal capsule with a crystallized magma chamber made at temperature and pressures relevant to shallow magma systems. The bottom right is a BSE image of the same experimental product featuring crystallized sanidine crystals (light grey) and rhyolite glass (dark grey). |
