(a) σ = 0
(b) σ = 0.1 × 10−3
(c) σ = 1 × 10−3
(d) σ = 5 × 10−3
(e) σ = 0.001
(f)
(g)
Figure 9: (a) Dimensionless time series illustrating the deterministic evolution of the calcite composition and the terrigenous composition at the bottom of the sediment when the system is subjected to weak periodic driving of period 105 a. The parameter values are those of case 2. The transients are omitted. (b–d) Calcite composition when the system is also subjected to colored noise fluctuations for a noise intensity of σ = 0.0001 (b), σ = 0.001 (c), and σ = 0.005 (d). (e) Power spectrum of (c). (f) 0-C residence time distribution for σ = 0.00125. (g) Signal-to-noise ratio as a function of the noise intensity.