[ancient_geezer]

Thus periods of 88k,83k,93k, and 130k to present.

One thing for you to think about, the other planets have a great deal of gravitational influence over the orbital plane of the earth. Time we spend within the mean solarplane gathering cometary debris varies even though the periodicity of the orbital precession/wobble is quite stable. The actual track of the earth through space in relation to the mean solarplane and debris in it is not a smooth nor symetrical function of time.

Read the paper: Origin of the 100 kyr Glacial Cycle

[per loin]

I tried that site, but it is malfunctioning (at an increasing frequency) in its delivery of graphics. I'll check it again in 100k years or so. :)