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Timescales of Magmatic ProcessesSince the seminal paper of Lasaga (1983) defining geospeedometry, the use of temperature-chemical-time data to determine geologic rates has been successfully applied to a wide range of igneous, metamorphic and planetary processes including the cooling of meteorites and the tempo of magmatic processes. The power of geospeedometry, also known as diffusion dating, lies in its potential to document rates of processes in any igneous or metamorphic rock that contains chemically zoned minerals over a wide range of timescales. A great review of application of diffusion dating or geospeedometry to igneous settings can be found here.
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Current research utilizes diffusion dating to determine the rates of processes leading to eruptions at a variety of volcano types including large silicic systems, arc volcanoes and back-arc volcanoes. In particular, ongoing research includes the use of high spatial resolution analytical techniques such as SIMS and NanoSIMS and experiments to expand and improve methods for diffusion dating, as well as unraveling the life stories and eruption triggers of individual magma bodies prior to eruption. This work is funded by an NSF CAREER grant to Till (EAR 1654584).
Case Study: The months leading to recent effusive eruptions at Yellowstone caldera
Super-eruptions are not the only type of eruption to be considered when evaluating hazards at volcanoes with protracted histories of eruption such as Yellowstone (Wyoming), Long Valley (California), and Valles (New Mexico) calderas. There have been 23+ effusive eruptions of rhyolite lava at Yellowstone since the last caldera forming eruption ~640,000 years ago, all of similar or greater magnitude than the largest volcanic eruptions of the 20th Century. We use NanoSIMS ion probe measurements to document very sharp concentration gradients over very short distances in igneous minerals, which allow a calculation of the timescale between reheating and eruption for the magma body of interest. Our results suggest an eruption at the beginning of Yellowstone’s most recent volcanic cycle was triggered within 10 months after reheating of a mostly crystallized magma reservoir following a 220,000-year period of volcanic quiescence. A similarly energetic reheating of Yellowstone’s current sub-surface magma bodies could end ~70,000 years of volcanic repose and lead to a future eruption over similar timescales. Fortunately any significant reheating event is likely to be identifiable by geophysical monitoring.
Related Publications:
Rubin, A.E., Cooper, K.M., Till, C.B., Kent, A.J., Costa, F., Bose, M., Gravely, D., Deering, C., Cole, J.., Rapid cooling and cold storage in a silicic magma reservoir recorded in individual crystals, Science, v. 356, p. 1154-1156.
Available Here
Till, C.B., Vazquez, J.A, Boyce, J.W., 2015, Months between rejuvenation and volcanic eruption at Yellowstone caldera, Wyoming, Geology, v.43, no. 8., doi:10.1130/G36862.1
Available Here
See "In the News" for news coverage and general audience pieces related to this research.
Other Recent Publications/Conference Proceedings on Our Work on Diffusion Dating:
K. Brugman, C.B. Till, M. Bose and R. Hervig, 2015, Development of Clinopyroxene as an Igneous Geospeedometer Using NanoSIMS, EOS AGU Fall Meeting Abstract V31B-3030.
S. Cichy, C. Till, K. Roggensack, R. Hervig, A. Clarke, Experimental Evidence for Fast Lithium Diffusion and Isotope Fractionation in Water-bearing Rhyolitic Melts at Magmatic Conditions, EOS AGU Fall Meeting Abstract V43C-3167
M. Coombs, J. Vazquez, L. Hayden, A. Calvert, M. Lidzbarski, N. Anderson, C. Till, 2015, Rejuvenation of shallow-crustal silicic magma bodies at Augustine and Hayes volcanoes, Alaska, EOS AGU Fall Meeting AbstractV42B-01
Till, C.B., Boyce, J.W., 2014, Interrogating Commonly Applied Initial Condition Assumptions in Geospeedometry using NanoSIMS, EOS, AGU Fall Meeting Abstract V33A-4823.
Rubin, A.E., Cooper, K.M., Kent, A.J.R., Costa Rodriguez, F., Till, C.B., 2014, Using Li Diffusion to Track Thermal Histories within Single Zircon Crystals, EOS, AGU Fall Meeting Abstract V31F-02.
Till, C.B., Vazquez, J.A., Boyce, J.W., Stelten, M., 2013, Probing the source and timing of rejuvenation and hybridization in post-caldera rhyolite magmas at Yellowstone Caldera, EOS, AGU Fall Meeting Abstract V53A-2763.
Till, C.B., Matthews, N.E., Vazquez, J.A., 2013, Refining the Chronology of IntraCaldera Magmatism Following the Formation of Yellowstone Caldera, Geological Society of America Abstracts with Programs, V. 45, No. 7, p.895.
Till, C.B., Vazquez, J.A., Boyce, J.W., Hitzman, C., 2012, Quantifying the interval between rejuvenation and eruption of rhyolite at Yellowstone caldera using high-resolution NanoSIMS geospeedometry, EOS, AGU Fall Meeting Abstract V43E-01.
Related Publications:
Rubin, A.E., Cooper, K.M., Till, C.B., Kent, A.J., Costa, F., Bose, M., Gravely, D., Deering, C., Cole, J.., Rapid cooling and cold storage in a silicic magma reservoir recorded in individual crystals, Science, v. 356, p. 1154-1156.
Available Here
Till, C.B., Vazquez, J.A, Boyce, J.W., 2015, Months between rejuvenation and volcanic eruption at Yellowstone caldera, Wyoming, Geology, v.43, no. 8., doi:10.1130/G36862.1
Available Here
See "In the News" for news coverage and general audience pieces related to this research.
Other Recent Publications/Conference Proceedings on Our Work on Diffusion Dating:
K. Brugman, C.B. Till, M. Bose and R. Hervig, 2015, Development of Clinopyroxene as an Igneous Geospeedometer Using NanoSIMS, EOS AGU Fall Meeting Abstract V31B-3030.
S. Cichy, C. Till, K. Roggensack, R. Hervig, A. Clarke, Experimental Evidence for Fast Lithium Diffusion and Isotope Fractionation in Water-bearing Rhyolitic Melts at Magmatic Conditions, EOS AGU Fall Meeting Abstract V43C-3167
M. Coombs, J. Vazquez, L. Hayden, A. Calvert, M. Lidzbarski, N. Anderson, C. Till, 2015, Rejuvenation of shallow-crustal silicic magma bodies at Augustine and Hayes volcanoes, Alaska, EOS AGU Fall Meeting AbstractV42B-01
Till, C.B., Boyce, J.W., 2014, Interrogating Commonly Applied Initial Condition Assumptions in Geospeedometry using NanoSIMS, EOS, AGU Fall Meeting Abstract V33A-4823.
Rubin, A.E., Cooper, K.M., Kent, A.J.R., Costa Rodriguez, F., Till, C.B., 2014, Using Li Diffusion to Track Thermal Histories within Single Zircon Crystals, EOS, AGU Fall Meeting Abstract V31F-02.
Till, C.B., Vazquez, J.A., Boyce, J.W., Stelten, M., 2013, Probing the source and timing of rejuvenation and hybridization in post-caldera rhyolite magmas at Yellowstone Caldera, EOS, AGU Fall Meeting Abstract V53A-2763.
Till, C.B., Matthews, N.E., Vazquez, J.A., 2013, Refining the Chronology of IntraCaldera Magmatism Following the Formation of Yellowstone Caldera, Geological Society of America Abstracts with Programs, V. 45, No. 7, p.895.
Till, C.B., Vazquez, J.A., Boyce, J.W., Hitzman, C., 2012, Quantifying the interval between rejuvenation and eruption of rhyolite at Yellowstone caldera using high-resolution NanoSIMS geospeedometry, EOS, AGU Fall Meeting Abstract V43E-01.