8523-36 The Basin Area
8523 - 33 to 37 - Snowy River Gorge.
This information has been developed from the publications:
|
Location: | 130550. 11 kilometres north-east of Buchan. | |
Abstract: | Exposure of Snowy River Volcanics and Buchan Caves Limestone with associated karst landforms, and river gorge on the Snowy River. | |
Access: | The Basin Road. | |
Ownership: | Predominantly private land with small Crown land reserve. | |
Geology: | Snowy River Volcanics and Buchan Caves Limestone display complex faulting in the Basin area. The faulting is particularly apparent in the volcanics where the normal stratigraphic sequence is obscure and rapid changes in lithology are common. The volcanics are representative of the upper part of the Snowy River Volcanics sequence and consist of rhyodacites, rhyolites, andesite, tuffs and sediments of the Fairy Member. Rhyodacites are predominant and are well exposed in Spooner Creek and in cliffs in the Snowy River, while rhyolites are exposed along the east bank of the lower Basin Creek. Flow structures are well developed in the rhyolites and these are enhanced by differential weathering of the softer bands at several localities. Highly weathered rocks occur near the junction of the Basin and Basin Ridge Roads while brecciated silicified tuff outcrops near the Basin Creek Bridge. This outcrop is of particular interest as it contains flattened tuff balls. Tuffs exposed in the Basin Creek area and in Blue Bullock Creek contain fine banding and complex current bedding which is clear evidence of reworking. Interbedded tuffs, agglomerate, dolomitic limestone and tuffaceous sandstone of the Spring Creek Member are exposed in the upper reaches of Blue Bullock Creek. A bank of limestone containing the coral Aulopora is also exposed in this area. Similar beds outcrop in the northern tributary to Spooner Creek. This sequence includes a distinctive red and white fossiliferous band of jasper with manganiferous partings. Within this band fossils are replaced by jasper and chalcedony. Buchan Caves Limestone is exposed in Basin and Spooner Creeks and northward toward Blue Bullock Creek. It consists of calcitic dolomite, massive laminated limestones and styolitic and grey calcarenite. The latter facies are moderately fossiliferous and contain corals, brachiopods and nautili’s. This fauna is representative of the Buchan Caves Limestone. In addition, richly fossiliferous muddy limestone and yellow calcareous mudstones outcrop in Spooner Creek. | |
Geomorphology: | The Snowy River valley side slopes are relatively gently sloping in the limestones of the Jacksons Crossing area and this valley form is contrasted with the gorge cut in rhyodacite to the south. The Basin limestone exposed on the eastern side of Basin Creek is characterized by several large dolines and many smaller solution features. Sixteen caves are known in this area although investigation of these systems, and the karst area in general, has been limited. Of the caves investigated Slocombes Cave (BA-1) appears to be the most significant. Cave development has occurred along a ramifying joint system and consists of low passage and several well decorated large chambers. This cave together with BA-11, provide sheltering sites for Bent Winged Bats. | |
Significance: | Regional. The exposures of the Snowy River Volcanics and Buchan Caves Limestone and the karst landforms occurring in the area warrant a Regional significance rating. More detailed investigation of the cave systems may reveal features of additional importance and may warrant an upgrading of the significance rating to the State level. | |
Management: | The cave systems of this site are the features most sensitive to degradation through inappropriate land use. There is insufficient knowledge of the cave system to allow the formulation of specific management prescriptions. However, land use which would result in ground vibration through the use of explosives or heavy machinery, or which would facilitate the uncontrolled use of the cave systems, or which may alter the amount and/or quality of surface and groundwater inputs to the cave systems, could significantly degrade the quality of the site. The management principles apply here. The significance of the Snowy River Gorge section in this area would be degraded by the construction of reservoirs. | |
References: | Kitson, A.E. 1907. 'Proposed reservation of limestone caves in the Buchan District, Eastern Gippland', Rec. geol. Surv. Vict., II(I) :37-44. Talent, J.A. 1965(B) 'The stratigraphic and diastrophic evolution of Central and Eastern Victoria in Middle Palaeozoic Times', Ibid, 79(1) :179-195. Matthews, P.G. (ed) 1968. Speleological Handbook. Victorian Speleological Association. Bradley, K. 1969. 'Geology of the Murrindal River - Yalmy River area east of Buchan, Victoria', Proc. R. Soc. Vict., 85 :277-285. | |
© State of Victoria (Agriculture Victoria) 1996 - .
This work, Victorian Resources Online, is licensed under a Creative Commons Attribution 4.0 licence. You are free to re-use the work under that licence, on the condition that you credit the State of Victoria (Agriculture Victoria) as author, indicate if changes were made and comply with the other licence terms.
The licence does not apply to ‘branding’ or some ‘images or photographs’ that may be owned by third parties. We ask you to seek prior approval to use images using the VRO feedback form. Access to higher quality images can also be provided on request.
This page was last updated on .