BY T. STEPHENS. 753 



has yet been published, may be offered as an excuse for bringing 

 to light these old Notes, with a few supplementary observations. 



River Tamar to River Forth. (Plate xxviii.). 



The West Head of the Tamar estuary is the terminal point of 

 a low range of the typical diabase of Eastern Tasmania. It is 

 flanked on the south and west by low sand dunes, and recent or 

 post-Tertiary drift, indicating probably the original outfall of the 

 River Tamar before it had excavated its present channel. West 

 of this is Badger Head, the most northerly point of the so-called 

 Asbestos Range, which derived its name from its erroneously 

 supposed connection with the serpentine country on Anderson's 

 Creek in which veins of chrysolite occur. The rocks of the 

 Badger Head country extend for about four miles westerly and 

 consist of micaceous schists, clay slates, and hard altered sand- 

 stones with laminations of white quartz, all highly inclined, 

 with numerous anticlinals. There is much foliation on the line 

 of strike, but the mean direction is about N. 30° West. Traces 

 of copper have been found on the western flank of the range. 



The Badger Head country is succeeded by low sand dunes and 

 drift extending to Port Sorell, with an outcrop of diabase, not 

 hitherto recorded, at the entrance of the Port. This is an out- 

 lier from the ridge on the western shore of Port Sorell, which is 

 the most prominent feature in this part of the district. Drift 

 gravels overlie parts of this ridge at an elevation up to 200 feet, 

 and are probably of Tertiary age. Isolated masses of a flat- 

 bedded sandstone showing signs of contact-metamorphism are 

 occasionally met with on exposed patches of the diabase, and 

 may possibly represent portions of the original covering when 

 the magma was intruded in the form of a sill or laccolite. 



The coast-line westward from Port Sorell Point for a distance 

 of some seven miles is fringed by sand dunes protecting a strip 

 of alluvial land formerly a marsh but now drained. This is for 

 the most part backed by basaltic country extending to and across 

 the River Mersey, except where it is interrupted by a low ridge 

 of diabase running southerly from the beach near Pardoe. On 

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