Sylvester has applied
microbeam techniques like LA-ICP-MS and
automated mineralogy (Mineral Liberation Analysis) to study the elemental and isotopic compositions of minerals, focusing on Earth's early crust,
meteorites,
impact melts, metal ores, and
sedimentary rock provenance. He examined the effects of collision pressures on granite formation, revealing smaller, cooler granites in high-pressure settings like the Himalayas and larger, hotter ones in high-temperature environments like the
Lachlan Fold Belt, with distinct geochemical signatures based on
protolith type. Collaboratively, he developed methods for high-precision elemental analysis using ICP-MS to trace geochemical variations, supporting research on high-field strength element
fractionation during the partial melting of the mantle wedge. Furthermore, he refined U–Pb zircon dating with LA-ICP-MS to near-SIMS (
secondary-ion mass spectrometry) precision, applying it to
detrital zircons from the Ulven Group (western Norway) and revealing a mix of
Archean,
Proterozoic, and early
Ordovician zircons. His work established LA-ICPMS as a viable alternative to SIMS for zircon geochronology, with further analysis of Zircon 91500 confirming its utility in calibrating
rare earth elements. His research also demonstrated the potential of
apatite for sedimentary provenance analysis, improved U-(Th-)Pb geochronology standards for zircon, monazite, and titanite, refining uncertainty propagation and data calibration and showed how
in situ analyses of Pb-isotope ratios in feldspar can be a powerful tool for understanding magmatic processes. Sylvester's work encompassed the isotopic study of meteorites, the effects of impact melting, and the formation of early solar system materials. He utilized laser ablation MC-ICP-MS to analyze Fe isotopic variations in iron meteorites and sulfides, demonstrating its ability to detect subtle differences in small samples. His comparative studies on impact melting revealed distinct compositions in melt products from sedimentary and crystalline targets, while his research on unequilibrated ordinary
chondrites suggested their formation as rapidly quenched liquids shaped by varied histories in the solar nebula. Among other works, he edited a special issue of
Tectonophysics titled "Continent Formation, Growth and Recycling," which explored perspectives on continental formation, growth, and recycling through numerical models, geochronologic and isotopic studies, and global crustal growth models. Sylvester edited the book
Laser-ablation-ICPMS in the Earth Sciences: Principles and Applications (2001) for the Mineralogical Association of Canada short course series, which Philip E. Janney reviewed, stating, "I was very impressed by the depth and scope of the book." In 2023, he was guest editor of ''Geostandards and Geoanalytical Research's'' issue highlighting innovations in LA-ICP-MS methods, instrumentation, and reference materials, sparked by the
pandemic's disruptions and opportunities in research. ==Awards and honors==