A HISTORY FO STAFFORDSHIRE 



and south, from off which they dip to all points of the compass, and are 

 broadest in the great central syncline occupied by the Keuper Marls. 



BUNTER PERIOD 



Lower Red and Mottled Sandstone. If the sub-aerial origin of the 

 Bunter, as is now generally accepted, be correct, we might expect to 

 find a varied distribution of the sediments ; especially would this be the 

 case with the wind-borne deposits, to which some geologists consider a 

 large portion of the Lower Mottled Sandstone may be directly or in- 

 directly attributed. To the west of Wolverhampton, where this sub- 

 division appears at its best, it reaches a thickness of 300 feet ; it is only 

 met with locally in North Staffordshire, and is altogether absent on the 

 east side of the South Staffordshire Coalfield. 



In the Wolverhampton area the strata consist of sandstones of the 

 most varied hues, ranging from yellow through brown to bright ver- 

 milion. Here also the remarkable false-bedding or ' oblique lamination,' 

 characteristic of the sub-division, is admirably exhibited in a road cutting 

 near the entrance to the lower town. Whether this be due to currents 

 of water or wind the general roundness of the sand particles must be 

 attributed to wind action, for no other agency is considered to be capable 

 of rounding small sand grains, while it is one of the characteristic features 

 of the desert sands of to-day. 1 



Owing to their soft nature the rocks are generally denuded into 

 broad valleys, but in the interesting escarpment of Kinver Edge the top 

 beds have been hardened by a calcareous cement, and overhang a deep 

 valley excavated in the underlying softer portion. The ease with which 

 the stone can be quarried has been taken advantage of by the inhabitants 

 of Enville and Kinver, the neighbourhood of these villages showing 

 numerous rock houses, of which those cut out of the sandstone of Holy 

 Austin Rock are the best known. 



Bunter Pebble Beds. The strata of this sub-division are well 

 developed in the north and south, where they hem in the Carboniferous 

 formations against which they abut, sometimes with a faulted junction, 

 but more frequently unconformably superimposed. They consist essen- 

 tially of coarse false-bedded sandstones, through which pebbles of vein 

 quartz and other rocks are widely scattered or are massed together 

 with little or no intervening matrix, forming beds of shingle sometimes 

 over 50 feet thick. At their outcrop the sandstones and conglomerates 

 are usually incoherent, but in wells and borings the matrix is often 

 highly calcareous, when the rock is intensely hard and much dreaded by 

 well-sinkers. In the shingle beds the pebbles are of all sizes up to or 

 slightly exceeding that of a man's head. The majority are quartzites 

 white, brown, yellow or liver-coloured ; others consist of well rounded 

 fragments of Mountain Limestone, chert, grits of various Palaeozoic 



1 For our knowledge of desert conditions the student is referred to Das gesetz der Wtistenbildung, by 

 Professor Walther (Berlin, 1900). 



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