part 2 J THE METAMORPHOSED ROCKS OE THE START AREA. 177 



On the eastern coast the cliffs at Hall Sands, south of the 

 JBickerton Valley, consist of gnarled and contorted mica-schists 

 overlain hy a narrow band of Green Schists clipping northwards.. 

 These Green Schists are exposed with the same disposition in. 

 greater mass in a quarry west of Hall Sands. 



The cliffs at Green Straight are regarded as Devonian rather- 

 than as altered members of the Green Schists, and the actual, 

 junction at the coast seems to be hidden in the valley itself. 



Area West of the Salcombe Estuary. 



In the area east of the Salcombe estuary, only one definite- 

 group of mica-schists has been recognized : the Start Schists,, 

 which underlie the anticlinorial limbs of the Green Schists of the 

 southern coast and of Southpool Creek ; but in the western area 

 the structural relations point clearly to a twofold division of the 

 mica-schists. As we proceed westwards, the two bands of Green 

 Schists of the eastern area are seen rapidly to converge into a single 

 folded mass west of Salcombe. As mentioned above, Ussher was 

 of opinion that in the Hope-Malborough section the Green-Schist 

 mass formed a syncline. On this interpretation, the mass of mica- 

 schists lying south of the united Green-Schist band is constituted 

 by Start Schists ; but the evidence for this interpretation is. 

 nowhere clear. 



An examination of the excellently exposed coast-section from 

 Ilbertstow Point to Bolt Head shows that the anticlinorial struc- 

 ture is still preserved, and that there is no evidence proving that 

 the southern band of the Green Schists from Fort Charles to South 

 Sands is an overturned syncline or isocline. 



The mica-schists form the core of the anticlinorial outcrop 

 along the Salcombe estuary from Fort Charles, where a fault is 

 well displayed bringing mica-schists against Green Schists along 

 the strike, to a point immediately below the Marine Hotel, at 

 which point the northern limb of the Green Schist is developed. 



Minor intercalated bands of Green Schist can be seen in the 

 mica-schists in the shore-section below Woodville. 



The lower mica-schists continue westwards in a wedge-shaped 

 outcrop to a point south-east of the village of Malborough, where 

 the northern and the southern band coalesce, and this single major 

 band continues westwards to Bolt Tail. 



It is unfortunate that, in this inland tract, exposures of the 

 rocks are few, and the detailed outcrops of the individual beds 

 cannot be accurately mapped, wherefore the boundaries of the 

 Green Schists shown on Ussher's map cannot be always guaranteed. 

 The major band of Green Schist, as we proceed westwards from 

 Malborough, swings slightly round to the south. 



In the section exposed at Bolt Tail, the Green Schists are highly 

 inclined. Their junction with the mica-schists of the Bolt mass 

 at Greystone Ledge shows the junction to dip at a high angle 

 northwards, and this high dip is the prevailing dip from that point 

 to Bolt Tail itself. 



