Sedimentary Rocks

Question 0

Aluminiumsilicate clays are

Answer 0

Clay minerals of sed rocks.

Question 1

Sedimentary rocks contain….

Answer 1

Quartz, mica, clay and some feldspar.

Question 2

Sedimentary carbonate rocks

Answer 2

Rocks with more than 50% calcium carbonate. 25% of sed rocks are in this group.

Question 3

Sedimentary rocks are fragments of pre-existing rocks that have….

Answer 3

Undergone sedimentation and lithification in the rock cycle. They accumulate together and are compressed and cemented during lithification.

Question 4

Pressure solution is a process where pressure increases,

Answer 4

Dissolving silica at point of contact where pressure of greatest during silica cementation.

Question 5

Calcite cemented sedimentary rocks are usually

Answer 5

Less porous than silica cemented rocks.

Question 6

Two major groups of sedimentary rocks

Answer 6

Rocks formed mainly of carbonate/calcite

And

Rocks formed mainly of fragments of silicate minerals.

Question 7

Three main types of limestone:

Answer 7

Shelly limestone - broken fragments of fossil shells, cemented by calcite.

Oolithic limestone - ooids
Crinoidal limestone - crinoids

Question 8

Conglomerate rock has various pebble sizes, 2mm - 64mm,

Answer 8

It’s composition is fragments (silica and quartz) in finer grained matrix, such as concrete.

Question 9

Sandstone, 0.64mm - 2mm,

Answer 9

Composed of quartz, mica and some feldspar.

Question 10

Mudstone (shale) is fine grained,

Answer 10

Composed of thin layers. It is soft and crumbles easily. Contains quartz and clay.

Question 11

Sedimentary rocks have no

Answer 11

Interlocking crystals, a granular texture and unconnected fragments.