© University of Liverpool, Department of Earth, Ocean & Ecological Sciences 2013
G E O - O E R
Sedimentary rocks
The following images show three clastic sedimentary rocks.
The grains in these three sedimentary rocks include lithic (rock) fragments and glauconite, feldspar, quartz and clay
mineral grains.
For each of the following sandstones identify the grain types,
grain sizes and shapes and the degree of sorting shown in the
thin section.
Which of these three sandstones is mineralogically and texturally
mature?
Which of these sandstones could only have formed in a marine
environment?
Which of these sandstones is
most likely to have been deposited by a turbidity current?
The following images show three limestones.
The main mineral in these rocks is calcite.
For each limestone identify the particles or grains (e.g. ooids, peloids, skeletal grains (or bioclasts), the matrix, which is usually micrite
(microcrystalline calcite) and the cement, which is usually sparite (sparry calcite crystals).
