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We use Chandra X-ray data to measure the metallicity of the intraclustermedium (ICM) in 245 massive galaxy clusters selected from X-ray andSunyaev-Zel'dovich (SZ) effect surveys, spanning redshifts $0<z<1.2$.Metallicities were measured in three different radial ranges, spanning clustercores through their outskirts. We explore trends in these measurements as afunction of cluster redshift, temperature, and surface brightness "peakiness"(a proxy for gas cooling efficiency in cluster centers). The data at largeradii (0.5--1 $r_{500}$) are consistent with a constant metallicity, while atintermediate radii (0.1-0.5 $r_{500}$) we see a late-time increase inenrichment, consistent with the expected production and mixing of metals incluster cores. In cluster centers, there are strong trends of metallicity withtemperature and peakiness, reflecting enhanced metal production in thelowest-entropy gas. Within the cool-core/sharply peaked cluster population,there is a large intrinsic scatter in central metallicity and no overallevolution, indicating significant astrophysical variations in the efficiency ofenrichment. The central metallicity in clusters with flat surface brightnessprofiles is lower, with a smaller intrinsic scatter, but increases towardslower redshifts. Our results are consistent with other recent measurements ofICM metallicity as a function of redshift. They reinforce the picture impliedby observations of uniform metal distributions in the outskirts of nearbyclusters, in which most of the enrichment of the ICM takes place before clusterformation, with significant later enrichment taking place only in clustercenters, as the stellar populations of the central galaxies evolve.

The Metallicity of the Intracluster Medium Over Cosmic Time: Further Evidence for Early Enrichment