Most of these marine fossils do not form in the far depths of the sea known as the Abyssal Zone because the sediment at the bottom of the Abyssal zone is generally dragged into the mantle of the Earth, as opposed to rising to the land.As said above, fossils usually form in water because sedimentation occurs.

Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology.

It is based on measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar).

Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed in order to analyze atmospheric conditions during different periods in history.

Dendrochronology is useful for determining the timing of events and rates of change in the environment (most prominently climate) and also in works of art and architecture, such as old panel paintings on wood, buildings, etc.

Fossils is an identification event which rotates with Rocks and Minerals every two years.

Students identify various fossilized animals and plants from the Fossil List, provide details about these organisms such as environment, mode of life, etc., and answer questions on general paleontology. The extreme heat and pressure needed to form igneous or metamorphic rock often destroys or warps the organism.

The amount of Argon sublimation that occurs is a function of the purity of the sample, the composition of the mother material, and a number of other factors.

These factors introduce error limits on the upper and lower bounds of dating, so that final determination of age is reliant on the environmental factors during formation, melting, and exposure to decreased pressure and/or open-air.

If one extrapolates the Lambda-CDM model backward from the earliest well-understood state, it quickly (within a small fraction of a second) reaches a singularity called the "Big Bang singularity".