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1. MAGMA EMPLACEMENT AND DIFFERENTIATION IN THE OLIGOCENE IXL PLUTON, NEVADA

   https://doi.org/10.1130/abs/2022AM-378854  

   Okhai, Disha; Eddy, Michael; DesOrmeau, Joel; Pamukcu, Ayla (January 2022, Geological Society of America)
2. Complementary crystal accumulation and rhyolite melt segregation in a late Miocene Andean pluton

   https://doi.org/10.1130/G39167.1  

   Schaen, Allen J.; Cottle, John M.; Singer, Brad S.; Keller, C. Brenhin; Garibaldi, Nicolas; Schoene, Blair (July 2017, Geology)
3. Transient rhyolite melt extraction to produce a shallow granitic pluton

   https://doi.org/10.1126/sciadv.abf0604  

   Schaen, Allen J.; Schoene, Blair; Dufek, Josef; Singer, Brad S.; Eddy, Michael P.; Jicha, Brian R.; Cottle, John M. (May 2021, Science Advances)

   Rhyolitic melt that fuels explosive eruptions often originates in the upper crust via extraction from crystal-rich sources, implying an evolutionary link between volcanism and residual plutonism. However, the time scales over which these systems evolve are mainly understood through erupted deposits, limiting confirmation of this connection. Exhumed plutons that preserve a record of high-silica melt segregation provide a critical subvolcanic perspective on rhyolite generation, permitting comparison between time scales of long-term assembly and transient melt extraction events. Here, U-Pb zircon petrochronology and 40 Ar/ 39 Ar thermochronology constrain silicic melt segregation and residual cumulate formation in a ~7 to 6 Ma, shallow (3 to 7 km depth) Andean pluton. Thermo-petrological simulations linked to a zircon saturation model map spatiotemporal melt flux distributions. Our findings suggest that ~50 km 3 of rhyolitic melt was extracted in ~130 ka, transient pluton assembly that indicates the thermal viability of advanced magma differentiation in the upper crust. 

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4. 'Defrosting' microstructures in the Jackass Lakes pluton and the Tuolumne intrusive complex, Sierra Nevada, California

   Melgar, A; Memeti, V (April 2025, Geological Society of America Abstracts with Programs)
5. The transition from magmatic to hydrothermal crystallization conditions of a shallow-level granitic pluton

   https://doi.org/10.1007/s00410-025-02280-y  

   Thompson, G_T; Rufledt, C_J; Thomas, J_B (January 2026, Contributions to Mineralogy and Petrology)

   Abstract Many thermobarometric methods applied to granitic composition rocks that crystallized at < 5 kbar yield temperature estimates ~ 50 to 100 °C lower than the widely used haplogranite water-saturated solidus. To address thermobarometric discrepancies, we investigated a shallow-level granitic pluton that is not enriched in fluxing elements such as Li, B, P, or F. The Rito del Medio pluton (RDMP) near Questa, New Mexico contains numerous minerals and inclusions suitable for thermobarometric estimates, and it has abundant miarolitic cavities that represent the final crystallization stages. Occurrences of coexisting melt and fluid inclusions show that groundmass minerals crystallized from a water-saturated magma. After groundmass crystallization, the pluton transitioned to a fluid-dominated system manifested by the crystallization of freestanding minerals contained in the miarolitic cavities. The granite contains mica, feldspar, quartz, primary fluid inclusions in quartz, and accessory minerals including garnet with quartz inclusions. We used minerals and their inclusions in both paragenetic contexts to track changes in P, T, and mineral and fluid compositions that accompanied the magmatic-to-hydrothermal transition. Resultant univariant curves from thermobarometry for the groundmass minerals converge at ~ 1.9 to 2.1 kbar and ~ 590 to 625 °C indicating final magmatic crystallization. To address discrepancies between thermobarometric results and the haplogranite solidus, we performed crystallization experiments at 2 kbar, which show that RDMP compositions magmas complete crystallization at temperatures ~ 620–625 °C. Univariant curves for thermobarometric approaches applied to the RDMP miarolitic cavity minerals converge at ~ 1.5 to 2.1 kbar and ~ 500 to 525 °C defining the transition to hydrothermal crystallization conditions. 

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