Siltstone

Siltstone

Siltstone: thin beds of silt-size grains, rare grading.

Siltstone: close up of thin beds of silt-size grains.

Siltstone: thinly bedded with dark grey glassy chert.

Siltstone: with sandy (white) base.

Siltstone: with upward pointing "flame" structure caused by injection of mud into overlying sandstone due to compression and dewatering.

Siltstone: with "dewatering" flame structure into overlying sandstone.

Siltstone: green siltstone transected by parallel fractures due to compression after lithification (turned to stone).

Metamorphosed siltstone: heat and pressure cause new, coarser minerals to form from the original clays in the mudstone beds.