The "mysterious forces" were the change in degree of radiation admitted onto the planet, dramatic climate change, the eradication of earth's original topography, geography, and mineral content change, earth's change in magnetic forces, and change in gravitational forces. It's proven that ferns grew at the poles and sea shells wound up on the top of Everest. The entire planet became another different planet -- calamitous, but hardly "mysterious."
All of those conditions can be re-created in a lab, and no one has ever been able to demonstrate the kind of decay rates they claim.