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Notes created & information organization based on the book:
"
The Dynamic Earth - an introduction to physical geology"
Brian Skinner & Stephen C. Porter   (further book information here)
also look at www.wiley.com for additional resource information
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Sediments & Sedimentation - Page 3

Lithification & Diagenesis

Remember from Chapter 1, lithos mean rock, and lithification means to make rock. Diagenesis is the complete process from beginning to end rock making.

Steps

Action

Explanation

1

compaction

Compacting is the expelling of water from between the grains. As the pore spaces reduced water is forced out and deposits those materials still in solution. They are often carbonate or silica based, and this material forms a cement in the pores.

2

cementation

3

recrystallization

Although not always a necessary step, there are times when a mineral will recrystallize to form a more stable structure. Aragonite often transforms via recrystallization to the more stable calcite. The cement between the joints may also undergo recrystallization after it has solidified.

Basic Sedimentary Rock types
Clastic sedimentary rocks

Starting Material

Sedimentary Rock

Gravel

Conglomerate

round shapes

Breccia

angular shapes

Sand

Sandstone

mainly quartz

arkosic sandstone
(Arkose)

mainly feldspar

lithic sandstone
(greywacke)

w/ many rock particles

Silt

Siltstone

quartz & feldspar

Clay

Shale

quartz & feldspar & clay

Conglomerate Breccia
Sandstone Shale
Siltstone lithic sandstone (greywacke)
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