Calling all Rock-Doctors - A bit of knowledge required please.

Yeah its vertical red rock formation mate.
Watch your tyres when driving near it, bit sharp :-))

G'day Mick

Nice images mate, but it all looks like a couple of piles of "schist" to me. ;0)

Mick,

Around the Broadhust range sandstone is the major rock type and is around 250 to 900 million years old It has been slightly metamorphosed resulting in the recrystallisation of the original quartz grains, and he clay between the grains has been replaced by sericite mica.

As far as I can tell there is no formal name for this formation.

Wayne

Dont know the name of it but eons ago Australia was under the sea.
During the very hot volcanic period the earth moved and squirmed and formed Australia and other places. That is why sea shells are found near the tops of mountains.
You probably know all that Mick but some may not

A very good example of the contorted rock formation is on the path into the Standley gorge in Karajini

Image Could Not Be Found

Image Could Not Be Found

I guess your pics are of similar but much more weathered.

Cheers

There is similar rock formations at Depot Glen (of Sturt fame) in NW NSW

Alan

"fold" is what the geos call it, however I drive too slow to be a geo, so can't be too sure.

Mick

In an earlier life I did a lot of rock climbing, so the grade and rock type was very important to us. What I think you’re looking at is scree, and the remnants of an old rock fall that was once layered on the face.

This sometimes happens with unstable sand stone that hasn’t matured to a dense state. I might be wrong without being there, because it’s very hard to make a judgement from a photograph.

However the whole face appears to been unstable indicating a very old rock wall that has eroded over time.

We’ll see what others have to say.

Cheers

Mick O, could be a form of Schist however Schist normally have a sheen/shine to them and are normally flaky, looks sedimentary ie highly compressed mud/sandstone. It is hard to identify unless sighted. The angles are caused be the earth's savage upheaval.
Seen it numerous times in the Pilbara, however never bothered to study it.
Must do so next time I'm up there.

Tony

Hi Mick, this might help. The sequence of metamorphism if the parent sedimentary rock is shale is: 1) slate - as in roof tiles. looks dull, has good cleavage in that it splits into thin layers. layers are straight
2) phyllite - shinier than slate , has a definite sheen. The pressure of squeezing the clay minerals in the shale turnis them into mica which gives the phyllite sheen. May start to show a gentle wave in the layers.
3) schist - greater pressure is making obvious folds, other new minerals growing so it looks banded.
4) gneiss - mottled almost looks like granite - think kitchen bench tops.
In fact if there is any more heat and pressure the rock will melt and become a magma and form true granite.


As another poster said, it's hard to tell without a sample in your hand. If it has tiny - say 0.2 to 0.4 mm particles that are shiny these would be quartz. so the parent could have been a mix of sand and mud and be called a siltstone. Sandstone metamorphoses into quartzite by heat and/or pressure.
The pix definitely show a slaty cleavage so mud dominates over sand. And it doesn't look to shiny. So IMO it's a low grade meta. rock, most probably a slate.. W