Flinders area, Victoria, Australiai

Regional Level Types
Flinders area	Area
Victoria	State
Australia	Country

The section of coastline between Cape Schanck and the township of Flinders on the Mornington Peninsula has been the most productive zeolite collecting areas in Victoria. The initial description of minerals in the Flinders area was made back in 1854 by A.R.C. Selwyn, the first Government Mineral Surveyor of Victoria. His report refers to carbonate mineralisation along the Bass Straight coast precisely where the township of Flinders is situated today. The zeolites analcite, chabazite, gmelinite and natrolite were first mentioned in reports in 1896.
"The Flinders 'plateau' basalts form part of the widespread Older Volcanics and cover the south-eastern portion of the Mornington Peninsula. Along the stretch of coast extending from West Head to Cape Schanck the basalts are exposed on steep cliffs up to 90 metres high and on wide shore platforms. The sequence is made up of numerous distinct lava flows, which are tilted eastward at a small angle east of Cape Schanck. Bores sunk by the Victorian Mines Department at Cape Schanck and Flinders in 1911, indicate an overall thickness of at least 650 metres for the basalts. The lava flows have been emplaced in rapid succession as they are often separated by thin partings of ash, tuff scoria or soils. The basalts at Flinders are regarded as Eocene to Miocene in age. Flows near the top of the sequence close to Flinders itself, have been dated at 42 million years old. They are mostly alkali olivine basalts."
The main mineralised locations in the Flinders area are as follows-
WEST HEAD (at Flinders township)
LITTLE BIRD ROCK
CAIRNS BAY (previously recorded as Simmons Bay)
BUSHRANGERS BAY (includes Elephant Rock)
CAPE SCHANCK
Highly vesicular Eocene olivine basalt flows of the Older Basalt are found along the coastline of the Mornington Peninsula between Flinders and Cape Schanck, particularly at Cairns Bay (= Simmons Bay) and Little Bird Rock (Birch, 1976; Coulsell, 1980; Birch, 1988b; Hall, 1989).

Colorless to white or pink trapezohedra of analcime, to 8 mm in diameter, are very abundant with some crystals up to 2 cm across. Analcime is the first zeolite to crystallize in the cavities (preceded only by montmorillonite) and is commonly overgrown by gmelinite/chabazite intergrowths and natrolite, with rarer thomsonite, copper, aragonite, calcite, or dolomite (Birch, 1988b). Rarely, tiny analcime crystals are found on natrolite and calcite (Hall, 1989).

Analcime, cowlesite, levyne-offretite, chabazite, and montmorillonite are found in vesicular basalt at Cairns Bay, near Flinders (Birch, 1988a). In the Cairns Bay and Little Bird Rock areas, it is believed that zeolites forming near the surface of an older basalt flow were covered and reheated by a younger flow (Rew, 1969). The reheating partly dissolved existing zeolites and redeposited new minerals as the solutions cooled.

With the exception of West Head named above, these localities are not in a specific Shire but are unincorporated and come under state control.

Localities in this Region

References