Southwestern Ohio's limestone (a sedimentary rock) is saturated with life — life from about 450 million years ago, that is. Our local limestone layers reflect times of relative prosperity for the wide ...

Mudstone, shale, and limestone are examples of sedimentary rock likely to contain fossils. As the layers of sediment build up on top of one another, they create a physical timeline. The oldest layers, ...

Scientists have found unusual, blueberry-like rocks on Mars that could give us more insights into its geological history.

The principle of superposition states that in an undeformed sequence of sedimentary rocks, each layer of rock is older than the one above it and younger than the one below it (Figures 1 and 2).

These are sedimentary rock layers chronicling Earth's geological history. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by ...

Over time, the layers are compressed and glued together.Metamorphic rocks are formed from other rocks, igneous or sedimentary, which are heated and compressed underground.Igneous rocks are formed ...