Metamorphic reactions provide crucial insights into the conditions that rocks experienced and significantly influence their rheological behaviour. However, some reactions are challenging to identify in the rock record. This study focuses on zonation and microstructures in plagioclase as indicators of metamorphic history, employing a case study from Lofoten, northern Norway, where various types of plagioclase microstructures ar...

Micrometer-scale Fe (iron)-rich filaments are common in mafic pyroclasts, yet their origin remains debated. These filaments have been variably interpreted as sutured fractures in magma, the product of magma mingling, compositional boundary layers detached from plagioclase crystals, or oxide shells stripped from bubbles. Here, we compare new observations from several case studies with previous results, concluding that shared fe...

Many experimental studies have addressed the crystallisation of zircon, not least because zircon is of paramount importance as a geochronometer. Today, it is well established at what temperature, melt composition, and Zr concentration a silicate melt reaches zircon saturation. It remains unclear though what course a Zr bearing melt takes before zircon appears as a macroscopic phase. Does zircon nucleate directly from the melt,...

Fe-oxide deposits of the Lahn-Dill-type in the eastern Rhenish Massif comprise haematite and quartz with minor siderite, magnetite, and calcite. The deposits are located in the hanging wall of thick volcaniclastic rock sequences and mark the Middle to Late Devonian boundary. Varying ore types with accompanying footwall rocks were sampled from two formerly important ore deposits, the Fortuna mine (Lahn syncline) and the Brilone...

U–Pb geochronology of shocked monazite can be used to date hypervelocity impact events. Impact-induced recrystallisation and formation of mechanical twins in monazite have been shown to result in radiogenic Pb loss and thus constrain impact ages. However, little is known about the effect of porosity on the U–Pb system in shocked monazite. Here we investigate monazite in two impact melt rocks from the Hiawatha impact structure,...

Normally, volatiles in silicate melts are ephemeral components that escape as gases when the melt reaches fluid saturation. When fluid saturation occurs at elevated pressure, magmatic fluids may have large amounts of oxide solute dissolved, are less volatile, and may resemble viscous gels. In Cyprus we have the rare case that solutes of a magmatic fluid coexist with H 2 O saturated basaltic to boninitic glasses. Quenching of t...

Raman spectroscopy has been widely used in mineralogy and petrology for identifying mineral phases. Some recent applications of Raman spectroscopy involve measuring the residual pressure of mineral inclusions, such as quartz inclusions in garnet host, to recover the entrapment pressure condition during metamorphism. The crystallographic orientations of entrapped inclusions and host are important to know for the modelling of th...