This document discusses different types of sedimentary rocks including clastic sedimentary rocks like breccia, conglomerate, sandstone, siltstone and shale formed from weathered debris. It also discusses chemical sedimentary rocks like limestone, evaporites including rock salt and gypsum, chert and coal. Finally, it mentions several sedimentary structures including cross bedded sandstone, graded bedding, mud cracks, ripple marks and trace fossils.
4. Clastic Sedimentary Rocks
Sandstones
Sandstone is a clastic
sedimentary rock made up mainly
of sand-size (1/16 to 2 millimeter
diameter) weathering debris.
Environments where large
amounts of sand can accumulate
include beaches, deserts, flood
plains and deltas.
5. Clastic Sedimentary Rocks
Siltstone is a clastic sedimentary
rock that forms from silt-size
(between 1/256 and 1/16
millimeter diameter) weathering
debris.
6. Clastic Sedimentary Rocks
Shale is a clastic sedimentary rock that is made
up of clay-size (less then 1/256 millimeter in
diameter) weathering debris. It typically breaks
into thin flat pieces.
7. Chemical Sedimentary Rocks
Limestone is a rock that is composed primarily
of calcium carbonate. It can form organically
from the accumulation of shell, coral, algal and
fecal debris. It can also form chemically from
the precipitation of calcium carbonate from
lake or ocean water.
9. Chemical Sedimentary Rocks
Chert is a microcrystalline or cryptocrystalline
sedimentary rock material composed of silicon
dioxide (SiO2). It breaks with a conchoidal
fracture, often producing very sharp edges
Coal is an organic sedimentary
rock that forms mainly from
plant debris.