Other information to be coupled with age of zircon Need to be done in-situ, so analysis can be performed on the same spot or very near; Provide additional information on physical conditions or petrogenesis of the source rocks. Radiogenic isotopes Hf isotopes (model ages and time of extraction from mantle) Stable isotopes Oxygen isotopes contributions from pre-existing crust; Temperature from Ti-thermometers physical conditions of zircon formation Other (less common) REE distributions other trace elements. Radiogenic isotopes (Lu-Hf decay) similar in behavior to Nd isotopes; less used conventionally; The great advantage of Hf isotopes is that they can be measured in situ via laser ablation using MC-ICP-MS Zircons have high Hf, low Lu concentrations; Newer setups (with two instruments) can utilize split-stream technology to measure age and Hf isotopes simultaneously. Usually expressed as Epsilon Hf units, just like Nd isotopes; Positive (Hf) values reflect primitive mantle sources, whereas lower values, sometimes highly negative, are indicative of old crustal components; Model ages represent approximate values of extraction from a mantle reservoir (such as DM or CHUR), and broadly represent lithospheric residence ages. Zhang et al., 2014, Lithos Zircon 18 O is a good indicator of pre-existing crust, just like quartz or other rock-forming minerals are in igneous rocks Zircon is in some ways better because is not prone to secondary modifications Mantle 18 O=5.5 permil (relative to SMOW) Crustal values are anywhere from 6 to 15 Complementary tool to Hf isotopes, strictly identifies pre-existing crust. Zircon 18 O need not be measured in-situ and is a common tool for igneous petrogenesis; In provenance studies, the strategy is to measure oxygen isotopes in conjunction with age, Hf isotopes etc; In-situ oxygen isotopes are being measured with high precision on small (few micron) spots using SIMS and equivalent instruments. Calibrated in the 1980s with major improvements over the past 5 years Ti concentration (measurable in-situ by SIMS) is directly proportional to the temperature of zircon formation; Spots dated by ICP can be assigned a physical property, namely temperature. Published papers show zircon grew in the age range anywhere from 350 to >1000 C. Ti concentration is directly proportional to the crystallization temperature (various calibrations, but mostly due to Harrison and Watson); Measurement can be performed by SIMS at very fine scale, microns. Mantle-like, primitive Hf and 18 O Temperatures are C, relatively low Zircons from these rocks indicate that silica differentiation here took place by closed system fractionation of some mantle-derived basalts.