I’ve been puzzled lately by the “Grand Canyon” escarpment south of Bundanoon, and before that by the escarpment at Fitzroy Falls.

Are these just southern extensions of the Illawarra escarpment that starts in the north at Stanwell Park / Coalcliff, and goes south via Bulli Pass and Macquarie Pass? Progressing along the northern and southern sides of the Shoalhaven River?

Does the escarpment continue south of the Shoalhaven?

mollwollfumble said:

I’ve been puzzled lately by the “Grand Canyon” escarpment south of Bundanoon, and before that by the escarpment at Fitzroy Falls.

Are these just southern extensions of the Illawarra escarpment that starts in the north at Stanwell Park / Coalcliff, and goes south via Bulli Pass and Macquarie Pass? Progressing along the northern and southern sides of the Shoalhaven River?

Does the escarpment continue south of the Shoalhaven?

Bump?

mollwollfumble said:

mollwollfumble said:

I’ve been puzzled lately by the “Grand Canyon” escarpment south of Bundanoon, and before that by the escarpment at Fitzroy Falls.

Are these just southern extensions of the Illawarra escarpment that starts in the north at Stanwell Park / Coalcliff, and goes south via Bulli Pass and Macquarie Pass? Progressing along the northern and southern sides of the Shoalhaven River?

Does the escarpment continue south of the Shoalhaven?

Bump?

https://www.environment.nsw.gov.au/research-and-publications/publications-search/illawarra-escarpment-state-conservation-area-draft-plan-of-management

The Illawarra escarpment, or officially the Illawarra Range, is the fold-created cliffs and plateau-eroded outcrop mountain range west of the Illawarra coastal plain south of Sydney, in the state of New South Wales, Australia. The range encloses the Illawarra region which stretches from Stanwell Park in the north to Kiama, Gerringong and the Shoalhaven River in the south.

https://en.wikipedia.org/wiki/Illawarra_escarpment

mollwollfumble said:

I’ve been puzzled lately by the “Grand Canyon” escarpment south of Bundanoon, and before that by the escarpment at Fitzroy Falls.

Are these just southern extensions of the Illawarra escarpment that starts in the north at Stanwell Park / Coalcliff, and goes south via Bulli Pass and Macquarie Pass? Progressing along the northern and southern sides of the Shoalhaven River?

Does the escarpment continue south of the Shoalhaven?

No.

“The Illawarra Escarpment stretches for around 120 km from the sea cliffs of the Royal National Park in the north to the junction of the Shoalhaven and Kangaroo Rivers in the south. Along its length the Illawarra Escarpment rises from 300 metres in the north, to 700m in the southern area around Albion Park.”

http://www.geomaps.com.au/scripts/illawarraescarpment.php

Or possibly yes.

It looks like the same sort of cliffs through the same Sydney sandstone.
(Where’s our geologist? )

—

I know it’s an amazing winding road from Fitzroy Falls down to Kangaroo Valley through some brilliant scenery. And the best way to see it is full bore….

Ian said:

mollwollfumble said:

I’ve been puzzled lately by the “Grand Canyon” escarpment south of Bundanoon, and before that by the escarpment at Fitzroy Falls.

Are these just southern extensions of the Illawarra escarpment that starts in the north at Stanwell Park / Coalcliff, and goes south via Bulli Pass and Macquarie Pass? Progressing along the northern and southern sides of the Shoalhaven River?

Does the escarpment continue south of the Shoalhaven?

No.

“The Illawarra Escarpment stretches for around 120 km from the sea cliffs of the Royal National Park in the north to the junction of the Shoalhaven and Kangaroo Rivers in the south. Along its length the Illawarra Escarpment rises from 300 metres in the north, to 700m in the southern area around Albion Park.”

http://www.geomaps.com.au/scripts/illawarraescarpment.php

Or possibly yes.

It looks like the same sort of cliffs through the same Sydney sandstone.
(Where’s our geologist? )

—

I know it’s an amazing winding road from Fitzroy Falls down to Kangaroo Valley through some brilliant scenery. And the best way to see it is full bore….

It looks like the same sort of cliffs through the same Sydney sandstone.
(Where’s our geologist? )

—————————————————————————————

IIRC, Pigeonhouse Mountain in the south is Nowra Sandstone, which it the basal (Permian ~ 290 ma) unit of the Sydney Basin in the south. Hawkesbury sandstone (Sydney area) is the second highest (Triassic ~ 200 ma) unit of the Sydney Basin.

The big sandstone cliffs of the Blue Mountains (eg The Three Sisters at Katoomba) are Narrabeen Group, (early Triassic ~250 Ma), which lies below the Hawkesbury Sandstone. They are in-between in age. Superficially similar, cliff-forming sandstones within the same region may not be the same. I can’t remember which sandstone is at Fitzroy Falls and Kangaroo Valley

Thanks Michael

> I know it’s an amazing winding road from Fitzroy Falls down to Kangaroo Valley through some brilliant scenery. And the best way to see it is full bore….

How would you fix Macquarie Pass on the Illawarra Highway, (Wollongong to Canberra via Robertson and Moss Vale)?

It’s a disaster, partly because of difficulty of going up the Illawarra escarpment, but also because of the crap road below the escarpment.

mollwollfumble said:

> I know it’s an amazing winding road from Fitzroy Falls down to Kangaroo Valley through some brilliant scenery. And the best way to see it is full bore….

How would you fix Macquarie Pass on the Illawarra Highway, (Wollongong to Canberra via Robertson and Moss Vale)?

It’s a disaster, partly because of difficulty of going up the Illawarra escarpment, but also because of the crap road below the escarpment.

If you’re asking me, I don’t know the Illawarra very well at all.. only been down that way a handful of times.