Transantarctic Mountains granitoid isotopic data

Abstract

We obtained new U-Pb ages and O-Hf isotopic compositions in zircons from nearly 40 samples of Ross Orogen granitoids covering a large section of the modern Transantarctic Mountains in Antarctica. New age and isotopic analysis of zircons from this large suite of Ross Orogen granitoids spanning >2,000 km along the orogen provide a wealth of new geochronologic, tracer, and inheritance information, enabling us to investigate the pace of magmatism, along-strike temporal and geochemical trends, sources of melts, and tectonic mode of convergence during magmatism. Data provided to the Data Repository include primary individual sample results of in situ analysis of zircon. Age and isotopic signatures were obtained by in situ analysis of the same zircon domains to first define ages by the U-Pb method, followed by O- and Hf-isotope analysis. U-Pb and O-isotope analysis were done by sensitive high-resolution ion microprobe (SHRIMP) at Australian National University, and precise Hf-isotope analysis was done using a laser ablation system coupled to a multi-collector inductively coupled plasma mass spectrometer (LA-MC-ICPMS) at Washington State University. Summary tabulations of the sample data are included with a manuscript. Also included is a narrative summary of zircon U-Pb age results for each sample, describing zircon characteristics and age interpretations.