Fig. 3
From: A novel chronostratigraphic framework for the Aptian–Albian paleoclimate events
Spectral analysis of the cyclostratigraphic series and SAR evaluation. (a–f) MS. (g–l) ARM. (a,g) Top: 5π multitaper power spectra, with the AR(1) red noise spectral model and median, 20% smoothed, 90%, and 99% confidence levels. Wavelengths of spectral peaks are labeled in cycles/m. MSB (green line) was removed by using high-pass filtering. (b,h) eFFT spectrograms, with each calculated spectrum normalized to 1. (e,k) Correlation coefficient (bulk) of COCO analysis38, with the optimal values. (c,i) Evolutionary correlation coefficient plus null hypothesis map38. Details in Supplementary Figs. S1 and S2. (f,l) Null hypothesis testing of COCO analysis38. (d,j) Null hypothesis testing of ASM analysis39,40 where the optimal value is highlighted in red. E = long eccentricity, e = short eccentricity, T = periodicities of ~ 60–70 kyr, O = obliquity, P = precession index.
