An error occurs in “Hydrothermal Alteration and Mineralization in the Neves-Corvo Volcanic-Hosted Massive Sulfide Deposit, Portugal: I. Geology, Mineralogy, and Geochemistry,” by Jorge M.R.S. Relvas et al. (Vol. 101, no. 4, p. 754, col. 1, line 6). The scale indicated should be 1:250. For members and subscribers, the corrected page can be found in the paper on the SEG website.