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Documenting the processes and timescales of magma formation and diversification and defining the locations, shapes, volumes, and phase states of magma storage and transport zones rely on data produced by novel analytical techniques and state-of-the-art experimental methods. Computational modeling effectively links these critical tools. The Magma Chamber Simulator (MCS) is an internally consistent thermodynamic open system model that uses experimental constraints from rhyolite MELTS (Gualda et al. 2012, Ghiorso & Gualda, 2015) to compute paths of open system magmas that evolve via processes including crystallization, magma mixing, cumulate/mush entrainment, and host-rock assimilation. MCS results yield elemental, isotope, mass, and thermal characteristics of melt ± crystals ± volatiles in "resident" magma, crustal wallrock (melt and solids), recharge magma, and entrained material. To model the petrochemical evolution of igneous rocks related by open-system processes, one typically runs 200+ models that vary initial compositions, pressures, and temperatures of magma, wallrock, etc. Comparison of model results with whole rock, mineral, and melt inclusion chemical data and other constraints (e.g., thermobarometry) yield interpretations about igneous processes at a range of scales—from how crust forms and evolves to processes responsible for in situ geochemical records of crystals—and allows assessment of epistemic and aleatoric uncertainties. Two examples of computational studies will illustrate MCS's utility and flexibility. (1) Modeling of historical basalts at Mt. Etna (Italy) provides evidence for variable degrees of melting of metasomatized mantle, followed by magma recharge and assimilation of partial melts of carbonate-flysch crust. (2) MCS models reproduce whole rock and mineral data of plagioclase-rich basalts at Steens Mountain (USA) through entrainment of gabbroic mush that likely formed in early stages of Columbia River Basalt magmatism. To enhance understanding of trans-lithospheric magma systems, future work on MCS will prioritize (i) building a post-processing environment that utilizes select statistical methods to inform "best-fit" models and to quantitatively assess uncertainty, and (ii) increasing modeling efficiency by adding automated modeling capabilities.
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Designing and Executing a Computational Petrology Research Project using Rhyolite-MELTS & Magma Chamber Simulator (MCS)
This workshop will provide strategies and techniques for designing and executing computational petrology research projects and will engage participants in using software called Rhyolite-MELTS and the Magma Chamber Simulator (MCS) to address questions about open system magma evolution. Participants will: Be introduced to petrologic and geochemical questions that can be addressed by computational tools such as Rhyolite-MELTS and MCS. Be presented with case studies that utilize these computational tools to address petrologic questions. Be introduced to computational research design strategies and data management techniques. Learn the limits of thermodynamic databases and the functionality of computational methods when applied to natural systems. Collaborate and discuss strategies to apply these techniques to petrologic scenarios provided by the conveners. Have the opportunity to pose questions to MCS and Rhyolite-MELTS experts that will aid in the set-up of their computational projects. Network and benefit from the experiences and expertise of other scientists. Petrologists of all levels are encouraged to join the workshop! If you need training on the use of these tools, we will provide Zoom sessions prior to the workshop, with dates to be determined. If you have already taken an MCS workshop or attended a MELTS short course, please consider joining us again for additional training on research project design and execution. MCS and rhyolite-MELTS can also be used as teaching tools for those interested in integration into petrology/geochemistry classes, so please sign up if you would like to use these tools in your classes. The workshop will take place Tuesday, 1st October and Wednesday, 2 October, 08:00-13:30 MST/UTC-7 on both days. Registration is done through the Goldschmidt2024 conference registration form. If you are registering for the workshop only and not participating in the conference, on the Registration Options page of the form, under "Conference Options", please select "Science Workshop Only Remote (no conference attendance)", then choose this workshop in the section "Post-Conference Science Workshop: Remote (October 2024)" before proceeding to payment.
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- Award ID(s):
- 2151038
- PAR ID:
- 10629387
- Publisher / Repository:
- Geochemical Society
- Date Published:
- Format(s):
- Medium: X
- Location:
- On line workshop, Goldschmidt Meeting 2024
- Sponsoring Org:
- National Science Foundation
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