Figure F48. Total color reflectance data on a timescale for Holes 1208A and 1209A plotted along with orbital obliquity and eccentricity for the (A) 0- to 2-Ma and (B) 3- to 5-Ma time intervals. These data suggest that the dominant cycle frequency over the last 0.7 m.y. is near that of the 100-k.y. eccentricity cycle. From 0.7 to 2.6 Ma, the dominant period shifts toward a higher frequency close to that associated with the 40-k.y. obliquity cycle. A long wavelength oscillation with a period of roughly 1.0 to 1.25 m.y. appears in the total color reflectance record from Site 1209 over the period 3 to 5 Ma. Comparison with the orbital curves suggest that this cycle may be in phase with the long period 1.25-m.y. cycle of obliquity.
Next Figure | Table of Contents