Coquina – cemented aggregate of geologically modern shell fragments.

Fossiliferous limestone – a

cemented aggregate of original shell

fragments, molds, and casts of ancient marine organisms.

Note fossil mold of a shell in this

specimen.

Peat, a mass of matted together plant material covered by H2O, which impedes decay. H2 and O2 are lost, concentrating carbon.

Lignite, so called “brown coal”, a soft

coal that forms when peat is

compressed and aged, about 40%

carbon.

Bituminous coal – soft coal formed when lignite is compacted and altered for millions of years, about 85% carbon, this coal is the most commonly mined and used for a fuel.

Sedimentary Rock Features Features in sedimentary rock that

reflect the sedimentary environment. Not found in other rock types. Features:

Stratification Fossils Ripple marks & crossbeds Mud cracks Nodules, concretions & geodes

Rock Stratification (layering) Bryce Canyon, UT

Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL

Ripple marks caused by wave action on the sandy bottom of a shallow bay

Almost identical ripple marks on the surface of a

sandstone millions of years

old.

Mud cracks in drying mud

Mud cracks preserved on the bedding surface of a

shale.

Groundwater dissolves hollow spaces in sedimentary rock, typically limestone, and mineral material is deposited inside the hollow with crystal points growing toward the center.

Geode

Thunder Egg

Cross-bedding at Checkerboard Mesa Zion National Park, UT

Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL

Dinosaur skeleton preserved in sedimentary rock - China

Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL