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Thursday 26 September 2013

UNCONFORMITY AT SOUTH BOWENFELS NEAR LITHGOW NEW SOUTH WALES AUSTRALIA

Aplite dyke intruding granite (very weathered)
This is the first purely geological entry I’ve written for this Blog. Most readers will be familiar with the basic geology of the western Blue Mountains. Essentially, there is a series of sedimentary rocks resting on an eroded surface of older rocks, both igneous and sedimentary. The rocks that we see from lookouts such as Echo Point or Govett’s Leap consist of Triassic sandstones and siltstones (the Narrabeen Group, which forms the cliffs) and the Permian Illawarra Coal Measures (nonmarine) and Shoalhaven Group (marine) which form the slopes and more level areas below.

Once Victoria Pass is descended into the Hartley Valley, there comes a point near Hartley where the Permian Shoalhaven Group sedimentary rocks gives way to the underlying granite, which occupies the lower ground. The sedimentary rocks and the granite are of quite different ages, Permian and Lower Carboniferous respectively, and the surface between them is called an unconformity (a time gap).
Shoalhaven Group conglomerate overlying weathered granite
At the very least, the time gap represented by this unconformity covers the time involved in forming the granite (as an intrusion into even older rocks), uplifting the earth’s crust and eroding away the overlying rocks and deeply weathering the now exposed granite. 

At this point in time the Sydney Basin began to form as the land subsided. The first sediments deposited in this vast subsiding area were the marine sandstones, conglomerates and siltstones of the Shoalhaven Group. These contain lots of pebbles (sometimes boulders) of the more resistant older local rocks. Most of these consist of hard quartzite, evidently derived from the nearby Upper Devonian Rydal Syncline. 
Detail of the unconformity
It’s not often you can put your finger on an unconformity like this, representing as it does perhaps 100 million years of time. The geological map is a small portion of one published in 1875 (see below). The excavation where the photographs were taken is in Portion 241. You can read the notes (21 and 22) which accompany the map. I have yet to find any pebbles containing Upper Devonian marine fossils nor any Permian marine fossils in the Shoalhaven Group sediments, but these are well known from other nearby localities. The cross section from the Sydney 1:250 000 geological map goes right through this spot and clearly shows the relationship between the various rocks.
A large quartzite cobble from the conglomerate.
 References: “Geological Map of the Districts of Hartley, Bowenfells, Wallerawang and Rydal” (Department of Mines, New South Wales, 1875). The DIGS reference is Heritage Map H0252. Geological Map of Sydney 3rd edition 1966. The DIGS reference simply says “Map”, so try using the Report Identification Number R00019218 instead.

View my Blue Mountains videos on my YouTube site here . I have three other playlists - on gem hunting/mining, Glen Innes and New Zealand.
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PAUL HARRIS LOOKOUT, BLACKHEATH BLUE MOUNTAINS NEW SOUTH WALES AUSTRALIA

LINKS TO ALL BLOG ENTRIES AND RELEVANT YOU TUBE VIDEOS

While this lookout lacks the grandeur of Govett’s Leap Lookout or Perry’s Lookdown, it has the advantage of being in a quiet location, with a pleasant view down Blackheath Glen and – sometimes the best of all – you will most likely have the place to yourself. The downside is that there are no toilets. Access is by going over the railway level crossing, turning left into Station Street and keeping straight ahead instead of going right to Shipley and Megalong Valley. It is located at the end of Staveley Parade, one of Blackheath’s earliest streets.The lookout was constructed in 1955 by the Blackheath Rotary Club, using funds bequeathed to the Club by Bill Tucker, one of its charter members. Tucker was much involved in community affairs, having served for some years on the Blackheath Municipal Council and especially with the local Horticultural Society.  The lookout is dedicated to the memory of Paul Percy Harris, who founded Rotary International in Chicago in 1905. The first Club in the Blue Mountains was formed in Katoomba in 1937. Blackheath followed in 1944.
Here is a link to a 1942 interview with Paul Harris on You Tube. View my Blue Mountains videos on my YouTube site here. The link to the video on Paul Harris Lookout is here .
I have three other playlists - on gem hunting/mining, Glen Innes and New Zealand.
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Saturday 21 September 2013

MT VICTORIA PARK BLUE MOUNTAINS NEW SOUTH WALES AUSTRALIA

Mt Victoria is on the western edge of the Blue Mountains. It came into existence mainly because of the coming of the railway in 1868, when it became the terminus while the Great Zig Zag was being constructed near Lithgow. This allowed the railway to descend from the mountains to the more fertile regions beyond. The development of Jenolan Caves as a tourist resort brought crowds to the town as it became the base for those coming from Sydney by train before transferring to road transport for the rest of the journey. Right from the construction of the first road across the Blue Mountains in 1815 until now, most road traffic has left the mountains at Mt Victoria.

Despite all of this development, the town’s population has not exceeded 1,000 and today it is a quiet mountain community which gives the impression that it plans to stay that way.

Mt Victoria Park is one of the most accessible spots along the Great Western Highway for travellers to stop for a break and they share it with the locals who clearly have a great deal of affection for the place.

Two of its entrances have signs over them; that from the Highway calls the place “Memorial Park” while the Station St entrance rather grandly states “Imperial Park Museum”. This reflects the fact that the two sections of the park had different origins. The First World War memorial is a prominent feature of one, the original community owned part, while the other was formerly the property of the Imperial Hotel (across the road). It contains a number of bizarre structures which look like they might have once have held exhibits of some sort, perhaps animal dioramas, though I haven’t been able to confirm this. See the photos at the end of this blog. The board appeared in the park early in 2016.
The two were merged as “Mt Victoria Park” when the Blue Mountains City Council bought the lower section from the Hotel owners in 1979.

The stimulus for the purchase of the land now forming the core of the park seems to have been the centenary of the crossing of the Blue Mountains in 1913. While nearby Mt York was the focal point for the unveiling of memorials (just as it has been in 2013 for the bicentenary), a site was needed which was more suitable for festivities, which was more accessible and could accommodate a crowd. You can read about all this in the newspapers of the day. The photograph (source unknown) show the crowds making their way to the park for the celebrations in May 1913.

The park became the venue for large picnic groups soon after this, since it is handy to the railway station. Railway picnics brought thousands and you could say “a good time was had by all”.

The construction of the War Memorial must have been a great event too, and the newspaper reports reveal the tremendous emotional energy behind the occasion. It seems strange to us that it should have been unveiled 5 months before the war concluded. Reading between the lines, it seems that feelings were running high in the community, as they were in many other small places where some men were perceived as not “doing their duty”.

Some recommended reading (source www.trove.nla.gov.au): The 1913 Centenary celebrations (Clarence and Richmond Examiner (Grafton, NSW: 1889 - 1915), Thursday 29 May 1913, page 5);  
The 1914 Railways Picnic (Nepean Times (Penrith, NSW): 1882 - 1962), Saturday 12 September 1914, page 6); 
The March of the “Cooees” (The Sydney Morning Herald (NSW: 1842 - 1954), Friday 5 November 1915, page 8); 
The opening of the War Memorial (The Blue Mountain Echo (NSW: 1909 - 1928), Friday 7 June 1918, page 3).

View my Blue Mountains videos here . I have three other playlists - gem hunting/mining, Glen Innes and New Zealand. The video about  Mt Victoria Park is here.
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This board appeared early in 2016
These are the three photographs on the information board.

Sunday 15 September 2013

THE ROUND WALK, KATOOMBA FALLS BLUE MOUNTAINS NEW SOUTH WALES AUSTRALIA

This walk may be commenced from either Scenic World or Katoomba Falls Reserve and it matters little in which direction you go. Parking and public transport is good at both places and refreshments are available close by. Coupled with fantastic scenery and a wide variety of plants to be seen along the way, this is an excellent walk, taking about an hour. 

The Witches Leap gap (often called the Witches Glen in older publications) provides an easy descent from road level. It is quite likely that this gap in the upper cliffs is a former course of Kedumba Creek, which now flows over the Katoomba Falls. The upper course of the creek, coming down from the vicinity of the Katoomba Aquatic Centre, lines up quite well with the gap and it’s possible that there is a former course of the creek concealed beneath the playing fields and the caravan park.

The 1894 historic map show a track descending into the valley in much the same place as today’s steps (near Vaniman’s Lookout). This would have been the beginning of the miner’s track down to the coal mines below what is now Scenic World. This track passed between the Orphan Rock and the upper cliff line before making a steep (and dangerous) descent to the level of today’s lower Scenic Railway station.

There are three principal lookouts along the track: Vaniman’s, Juliet’s Balcony and Rainforest Lookout, though the third is a little below the track it is well worth including in the walk.

Chester Melvin Vaniman was a celebrated American photographer and artist who visited the Blue Mountains in 1903. The lookout provides a great view of the Falls and the Three Sisters. It is on that section of the Round Walk which is actually part of the Prince Henry Cliff Walk, close to where the track descends into the valley.

Juliet’s Balcony is a well located lookout somewhat further down and gives a full length view of both Upper and Lower Katoomba Falls.

Rainforest Lookout is lower down again; unlike the upper lookouts this one is surrounded by lush vegetation and also has a great view of the falls.
View from Vaniman's Lookout 2011

View from Juliet's Balcony 2007
See the Wild Walks download on this walk for more information here .
View my Blue Mountains videos here. I have three other playlists - , gem hunting/geology, Glen Innes and New Zealand. The Round Walk video is here .

Rainforest Lookout around 1905
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Sunday 8 September 2013

GORDON FALLS LOOKOUT AND ELYSIAN ROCK, LEURA BLUE MOUNTAINS NEW SOUTH WALES AUSTRALIA

See the blog entry on Gordon Falls Reserve, which gives details of the origin of the reserve and also my You Tube videos on the area.For a good read, go to Trove (trove.nla.gov.au) and look up the story printed in “The Blue Mountain Echo” (NSW: 1909 - 1928) for Friday 18 April 1919. The author must have walked down to or close to the site of the present lookout to have been able to see the waterfall. The Lookout is easily reached from the parking area. Before getting even that far, you will pass an old painted sign on the left, on which the faint words “Fairy Dell” can just be discerned. The sign has gone now (June 2021).
This could refer to “Fairy Glen”, accessed by a track now out of use leading from the Lookout track. See the sample page from “Mountain Mist Books” here on how to locate this old track. On the other hand, the map shows Fairy Dell below the cliff line. Another good read from “The Blue Mountain Echo” from September 1913 shows how Alderman Lindeman was thinking about the pass in the valley below which now bears his name. See here .

Gordon Falls Lookout is a good place to view the Three Sisters from the “other side”, which looks decidedly unusual for those who only know the Echo Point aspect. You can view both the upper and lower falls by craning your neck a bit. See this Wild Walks file here for more information.
The lower fall
The upper fall
The Prince Henry Cliff Walk commences at Gordon Falls, and the first lookout encountered is at Elysian Rock. The track (August 2013) was closed beyond this point because of bushfire damage, but reopened several years ago. You can return to the parking area via the steps up to Olympian Parade. See this Wild Walks here file for more information.

Until the construction of the Prince Henry Cliff Walk in the 1930’s, the three rock lookouts (Elysian, Olympian and Tarpeian) each had separate access tracks, which remain to this day. It is to be hoped that the Cliff Walk track which links them will be reopened soon. (It was, about 18 months later, after reconstruction of the Buttenshaw Bridge).
The Elysian Fields or Elysium is, in Greek mythology, a place of perfect happiness prepared by the gods for the worthy dead. No doubt this is where the Rock derives its name, which is a cut above all the Fairy Dells and Fairy Glens in the Blue Mountains.

My video of this walk will be found here . View my Blue Mountains videos on my You Tube site here . I have three other playlists - on gem hunting/geology, Glen Innes and New Zealand.
All New England and other Geology blogs and videos