Figure 3. Power spectra calculated from the unsmoothed terrigenous flux time series for (A) Site 1018 and (B) Site 1020 shows significant variability at major orbital periodicities. Terrigenous grain-size data from (C) Site 1018 and (D) Site 1020 display much higher frequency variability and no obvious relationship to orbital cycles. Blackman-Tukey spectral analysis performed using Analyseries software package. Bandwidth is 0.009752 with a time step of 2 k.y. and 87 lags.

Figure 3. Power spectra calculated from the unsmoothed terrigenous flux time series for (A) Site 1018 and (B) Site 1020 shows significant variability at major orbital periodicities. Terrigenous grain-size data from (C) Site 1018 and (D) Site 1020 display much higher frequency variability and no obvious relationship to orbital cycles. Blackman-Tukey spectral analysis performed using Analyseries software package. Bandwidth is 0.009752 with a time step of 2 k.y. and 87 lags.