CHIME dating of monazite from the Dongqing pluton in SE Jilin, China

The Dongqing pluton in the Zhangguangcai Range, NE China comprises two-mica monzogranite and garnet-bearing two-mica monzogranite with subordinate garnetbearing muscovite alkali-feldspar granite. The monzogranite was dated as 208 Ma by the ^208Pb/^232Th monazite dating (Fang, 1992) and ca. 160 Ma by the Rb-Sr and Sm-Nd methods (Wu et al., 2004). To examine the discrepancy, monazite from the monzogranite was dated by the CHIME method coupled with age mapping. Monazite grains show significant compositional variation in concentric and sector fashions, but are chronologically uniform. Individual sets of ThO2, UO2 and PbO analyses were screened by the chemical criteria, 0.96