![]() Careful consideration of the size of the equilibration volume, the constituents that comprise the effective bulk composition, and the best technique to employ for its determination based on rock type and petrographic character, offer the best chance to produce trustworthy data from pseudosection analysis. Windows XP Service Pack 3 SP 3 Windows XP Service Pack 3 Build 5512 FINAL Kobo Desktop 3.12. Firefox is a fast, full-featured Web browser. The main discrepancies relate to varying proportions of matrix phases (primarily mica) relative to porphyroblasts (primarily staurolite and kyanite), indicating that point counting preserves small-scale petrographic features that are otherwise averaged out in XRF analysis of a larger sample. Download JMicroVision 1.2.7 for Mac Free Home Mac Photo & Design Graphics Tools JMicroVision Screenshots JMicroVision 1.2.7 Screenshots Mozilla Firefox 104.0.2. Pseudosections constructed for individual point count-derived bulks accurately reproduce this variability on a case-by-case basis, though averaged proportions do not correlate with those calculated at equivalent peak P–T conditions for a whole-rock XRF-derived bulk composition. Bulk compositions determined from multiple thin sections of a heterogeneous garnet–staurolite–kyanite schist show a wide range in major-element oxides, owing to notable variation in mineral proportions. The actual developer of the free software is JMicroVision. JMicroVision is compatible with Windows XP/Vista/7/8/10/11 environment, 32-bit version. We cannot confirm if there is a free download of this software available. Absolute displacements of equilibria can approach ☑ kbar for only a moderate degree of modal proportion uncertainty, thus being essentially similar to the magnitudes reported for analytical uncertainties in conventional thermobarometry. There was a download of JMicroVision 1.2.7 on the developer's website when we last checked. The mineral determination of single crystals retrieved from in situ frosted. 10 Getting Started Click: To: Contents View the table of contents of the online Help. We show that only minor mineralogical variation at the thin-section scale propagates through the phase equilibria modelling procedure and affects the absolute P–T conditions at which key assemblages are stable. images by random point counting using the JMicroVision software (Roduit, 2007). Two case study examples-a garnet–cordierite granofels and a garnet–staurolite–kyanite schist-are used to compare the relative importance that geological uncertainty has on bulk compositions determined via (1) X-ray fluorescence (XRF) or (2) point counting techniques. Such uncertainty influences the sample's bulk composition, which is the primary control on its equilibrium phase relationships and thus the interpreted pressure–temperature ( P–T) conditions of formation. Of the several factors that can affect the accuracy and precision of such calculated phase diagrams, “geological” uncertainty related to natural petrographic variation at the hand sample- and/or thin section-scale is rarely considered. Pseudosection modelling is rapidly becoming an essential part of a petrologist's toolkit and often forms the basis of interpreting the tectonothermal evolution of a rock sample, outcrop, or geological region. ![]()
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