Description
Summary:The age and conditions of metamorphism of the Windmill Islands were investigated using samples collected in the 2013/2014 field season from locations throughout the Windmill Islands region. The Windmill Islands vary in metamorphic grade, from amphibolite-facies in the north, to high-grade granulite-facies in the south. Samples were selected from peninsulas and islands from north to south to explore the changing conditions in detail throughout the region. These are interim results and further work will be undertaken in 2015, particularly to further constrain the P-T conditions. A list and short summary of all files is provided below. Detailed methodology for data collection is provided in summaries 1 and 2. Sampling locations Summary 1 (table 1) provides a table summarising sampling locations for selected samples (.docx file) Appendix 1- gives all GPS coordinates for sampling locations (.xls file) Appendix 2- Field photographs from selected locations (.pdf file) Data relating to age Summary 1- provides information on sample locations for geochronology, methodology for LAICPMS and SHRIMP geochronology and a summary of results (.docx file) Figure 1- U-Pb zircon concordia plots from four structurally constrained magmatic rocks, collected by Post (2000), has been added to further constrain the timing of deformation (.pdf file) Figure 2- U-Pb monazite concordia plots from metapelites to constrain timing of metamorphism (.pdf file) Table 2- All SHRIMP U-Pb analyses from structurally controlled magmatic rocks (.xls file) Table 3- All U-Pb LAICPMS monazite analyses from metapelites (.xls file) Data relating to constraining metamorphic conditions Summary 2- information on methodology for constraining PT conditions, petrographic descriptions of selected samples and an explanation of the calculated metamorphic phase diagram (.docx file) Figure 3- Photomicrographs from selected samples (referred to petrography section of summary 2) (.pdf file) Figure 4- Calculated metamorphic phase diagram from sample WI-1B (.pdf file) Table 4- whole rock geochemistry for selected samples, with major elements used for the calculation of metamorphic phase equilibria (.xls file) Table 5- electron microprobe analyses for selected samples (interim- more to be collected) (.xls file)