Friday 27 January 2006.

Snowy Visitor Centre. The Snowy Visitor Centre, in Jindabyne, is a showy, plush, comfortable, air-conditioned building. It displayed information about the environment of the region and the water management of the area. This could be enjoyed by the general public and school groups. There is a large sales area and comfortable coffee lounge. The film Kosciuszko Reflections; showed the beautiful landscapes and the flora and fauna of the alpine area.

Jindabyne Dam Project. A hydro power station is being constructed below the dam wall. This is to generate electricity from the increased amount of water to be released into the Snowy River on environmental grounds.

Bullock’s Flat. We traveled past the terminal of the tube train to arrive on Bullock’s Flat at the junction of Thredbo River and Little Thredbo River. It was developed as a private holiday house in 1930’s and 1940’s by Dr Bullock from Sydney. The surviving buildings are well preserved and surrounded by apple and elm trees sheltered by a Hawthorn hedge. One suspects excellent trout fishing in the adjoining river and horse riding and bush walking were enjoyed by the family.

Walking along the river today we noted, as well as the abundance of weeds, many native species including Poison Riceflower, Small Hakea and River Bottlebrush. Birds were plentiful but speedy, except Coots and Black and Wood Ducks on the lake. We saw Sacred Kingfisher, Superb Fairywrens, and Yellow-faced and White-eared Honeyeaters. Under the tube train bridge were many Welcome Swallow nests, one containing 4 chicks. Damage to window frames of the outhouse was attributed to the beaks of some member of the parrot family.

An interesting rock was observed. It was a dollop of coarse-grained granite fused to a large block of greenstone xenolith.

Thredbo River Picnic Area. By now the atmosphere was hot and humid and the cloud cover of midday had gone. In the river bubbles were being emitted at intervals rhythmically. Hope was expressed the optimistic that they may have come from a platypus which had not appeared by the time we left. Along the river was a rich mix of indigenous plants and exotics that have been prevalent at sites previously visited. Our group was interested in the Mountain Correa in different hues from green to red. River Lomatia had grevillea like flowers and dried seedpods.

Birds were everywhere hiding in the dense undergrowth. Those seen included White-throated Treecreeper, Yellow Robins with young, Sacred Kingfisher, Crimson Rosella and Gang-gang Cockatoo. Honeyeaters seen were Brown-headed, Yellow-faced, White-naped and White-eared. A Striated Pardalote was noted tending its burrow 2m above the ground level in a large Swamp Gum.

General observations during the day worth noting:

• Evidence of prevalent Wombats was present in the form of many freshly used burrows and plentiful blocky scats. Other plentiful scats included fox, deer and rabbit.
• There was a carcass of an Eastern Grey Kangaroo at Bullock’s Flat (not inspected closely!).
• Exotic weeds: Paterson’s curse, skeleton weed, flat weed, thistles, teasel and saffron were prevalent. It was of interest that the Hawthorn hedge had not spread much in spite of having bird friendly fruit. Apple trees are spreading and poplars and willows are threatening to become a nuisance. It is interesting that some weeds run riot where others are reasonably benign.

Bill and Sheila Walker, Margaret and Graeme Batey, Don Robertson.

Xenolith at Bullock’s Flat. An interesting excavated rock was found at Bullock’s Flat about 100m east of the Thredbo River. The rock was of two types – Gneissic granite above and Greenstone below. The greenstone portion was larger than the granite. Greenstone is undersea basalt poured of an oceanic rift in the Cambrian period. There are only a few outcrops of greenstone in Victoria and these occur along prominent N-S faults such as West and East of the Grampians, the Heathcote-Colbinabbin fault, Dookie-Tatong, Mt Wellington, etc. Perhaps one or more of these greenstone outcrops projected into NSW.

It would be difficult for the Kosciuszko granite to assimilate the Cambrian Greenstone as the greenstone minerals like augite and olivine crystallize out well above the temperature of the granite minerals like biotite, hornblende and quartz. All the granite could do would be to surround greenstone and not react chemically with it.

It is hard to conceive all this from a block like that seen at Bullock’s Flat. It would be interesting to see the two rocks in situ in their original position. More greenstone was seen at Sawpit Creek.

Noel Schleiger

1: Willow Herb at Bullock's Flat.
2: Insect scribbles on gum. Dinner Flat.
Photos: Rosalind Smallwood.