C.—GEOLOGY 67 
group, and much of the Corley and Lower Enville beds. Several of them 
line up with older breaks in the pre-Carboniferous platform, and many 
are known to have continued their displacement during and after the 
deposition of the Trias. Marl conglomerates towards the top of the 
Upper Coal Measures suggest contemporaneous movement of neighbouring 
faults, but pebble and breccia beds are torrent-borne from southern lands, 
and the main displacement of both folds and faults is later than the Upper 
Coal Measures deposits. Possibly the latest Enville, Corley and Erbistock 
beds are contemporaneous with some Magnesian Limestone, but proof is 
lacking, and the steady structure demonstrated in the basal Permian 
peneplain is not yet recognised west of Derbyshire. 
There being no fossils in the Trias of the Midland Province, the age of 
movements affecting it cannot be checked by zoning. Wedges of Bunter _ 
Sands and Keuper Marls in Nottingham overlap the wedge of Magnesian 
Limestone to rest on Coal Measures and older rocks in Derbyshire and 
Leicestershire. ‘Tilting continued with sedimentation, and east of the 
Pennines the sloping surface of concealed Coal Measures is buried under 
a thousand yards of Permian and Trias within a few miles east of the 
Trent. The great basin of Cheshire with its salt beds, and Shropshire 
with its patch of Lias, downfolded as it filled. Its depth and what lies 
under it are matters for conjecture, but the Plumley borehole pierced 
2,500 ft. of Keuper, and Bunter Beds at Heswall have been proved 
2,200 ft. thick. The turn-up of Trias to the western anticline of 
Staffordshire, and the Red Rock Fault of Cheshire, is evidence of further 
substantial settlement, since the deposition of the down-tilted beds. 
The Trias basin of Staffordshire sagged as a duplex trough on either 
side of the faulted saddle of the Black Country. ‘The western downfold, 
like the Shropshire basin, is edged about with latest Carboniferous Red 
Beds, and within it conformable passage between the two formations is 
not impossible. In the depression to the east of Stafford, the Chartley 
boring passed through 2,000 ft. of Trias, and outliers of Rhztic lie further 
to the east. From the north part of this basin fingers of Bunter extend 
along steep-sided valleys scored in the southern ending of the Pennines. 
The edges of the Leicestershire platform are also ragged ; and against and 
over them Bunter is overlapped by Keuper, which completes the transgres- 
sion of ‘Trias across the coalfield synclines of Warwickshire and Leicester- 
shire, and overtops the sharp, upstanding peaks of Charnwood Forest. 
That core of Pre-Cambrian in Charnwood, along with the western portion 
of the Pennine block, must have been elevated as the Nottinghamshire, 
Staffordshire and Cheshire Trias basins were being filled. Eventually 
all elevations, cluttered up in their own debris, were buried under the 
great bulk of material washed to the Midlands by torrents or wind-swept 
from the foothills of the great Hercynian Chain. By the time the desert 
deposits of the Keuper were covered by the Rhztic Sea, the whole Midland 
Province had been upgraded to a plain. 
Wherever there is exposure of bare rock, and diversity of rock character 
_ to show it, there is evidence that the even lie of Trias and post-'Triassic 
_ rocks has been disturbed by later movements, but in the Midland Coalfield 
Province, except for certain arcuate groups of east-west faults which cross 
