The sandstone is mainly composed of thin to thick bedded, gray to whitish gray to brown sandstone that is fine to medium grained and displays some laminations, ripple marks
, flat beds and cross beds at places.
, associated with the hardground in the Vasalemma quarry, were described in detail by Hints & Miidel (2008).
Above the basal conglomerate of the Tapeats, the rest of the formation is composed of sand about 200 feet thick, with bedding containing sedimentary structures typical of tidal flat, beach, and shallow-shore environments that include ripple marks
, mud cracks, and raindrop prints (Fig.
on the sandstone indicate the creature was struggling to swim against a current.
left by the sea can still be seen in the sandstone on the summit of Pen y Fan.
Most of us admit that our very best pictures of rocks were achieved by surreptitiously pointing our cameras over his shoulder when he had carefully selected the right angle to catch the shadows on a mountain range or on a row of ripple marks
Fossilised ripple marks
in sand formed by water currents are preserved at Black Pastures Quarry, near Chollerford, where even the casts created by burrowing worms 325 million years ago can be seen.
At the bottom of the steps leading up to the jubilee tower at Castle Hill look for the ripple marks
still visible on the paving stones.
The clincher for some of the water being on the surface is crossbeds and ripple marks
in the rocks," says Mars rover project scientist Joy A.
The pattern of ripple marks
and other features locked in southwestern Utah's sandstone indicates that the mineral grains had been blown in from those directions.
Schlieren exhibit layering similar to cross-bedding and preserve ripple marks
along their base.
Well-preserved ripple marks
and rip-up clasts have been observed in the immediate hanging wall.