Fig. 3: Triple-isotope plot for the Pb (i.e., 208Pb/206Pb vs. 206Pb/207Pb) in Dongsha coral DS86.
From: Coral records indicate six-decade rise and fall of atmospheric lead emission in China
Given the changing sources of Pb over time, we divide the record into four periods: (I) 1953-1960, (II) 1961-early 1980s, (III) mid 1980s-mid 2000s, and (IV) mid 2000s-2016. The red line represents a Chinese Pb isotopic signature, delineating the relationship between Pb/Zn ores (blue area) and coals (yellow area) found within China16. The blue dashed line represents a binary mixing line between the typical Australian Pb (by average, 206Pb/207Pb = 1.041, 208Pb/206Pb = 2.225) and U.S. Pb (by average, 206Pb/207Pb = 1.200, 208Pb/206Pb = 2.050) ores used in Pb gasoline additives44. In the lower left corner, the triple-isotope plot shows broad coverages of Pb isotopes in different sources from China (namely, Pb/Zn ores and coals) together with the Australian-US Pb mixing line and Chinese Pb line.
