# Rock Layers & Relative Dating

Understand that rock layers (strata) form in sequence with the oldest at the bottom and the youngest at the top, and that fossils found in deeper layers are older — this is the principle of relative dating

Builds on: How Fossils Form (hard, https://ai.page/c/how-fossils-form/en.md), Types of Rock (soft, https://ai.page/c/types-of-rock/en.md), Properties of materials (soft, https://ai.page/c/properties-of-materials/en.md), The Mesozoic Era (soft, https://ai.page/c/the-mesozoic-era/en.md)

Concept id: rock-layers-and-relative-dating. Subject: science. Licence: CC BY-SA 4.0.

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