Figure 4
From: Coral geochemical response to uplift in the aftermath of the 2005 Nias–Simeulue earthquake
Coral Y/Ca records before and after the March 2005 earthquake. Results are shown as 10-pt running means for the 2.5A and 1.8A uplift sites (a, b) and the M0.4A subsidence site (c) versus time. Yellow bar shows the earthquake; purple bar marks the December 2004 Indian Ocean tsunami. Profiles with significant pre- and post-earthquake differences in Y/Ca are indicated by their non-overlapping means (horizontal lines) with shaded 95% confidence envelopes (1.96× standard error of the mean, see t-test results in Supplementary Table 1). Color-coded change points with posterior probability estimates83 confirm the presence of both transient and step-change earthquake signals at the 2.5A and 1.8A uplift sites. Paired change points for profiles 2.5A-1, 2.5A-3, 1.8A-2, and 1.8A-6 mark significant transient increases in Y/Ca. A change point also corresponds with the decrease in Y/Ca at subsidence site M0.4A-3. Change points occurring between 2004.5 and 2005.8 (inclusive of the tsunami and earthquake events) are filled, while those occurring outside of this range are grey. The reef-response interval following the earthquake at uplift sites is highlighted.
