JD. Jones — Denudation of Coalhrooh-dale. 207 



Indeed, the younger Coal-measures not only fill up the vacuity 

 and cover over portions of the older strata, but range over a large 

 area to the south, as far as the Abberley Hills, in some places being 

 not less than 1100 feet thick, as shown by the sinking at Shatterford. 



I wish it to be clearly understood that the denudation to which I 

 refer in this paper is that which took place previous to the deposit of 

 the younger Coal-measures. This does not account for the exact 

 condition of things in those parts of the Coal-field in which the younger 

 Coal-measures are absent, as at the Hatch and Steeraway, where we 

 find isolated patches of the lower coals. Several periods of after 

 denudation may have caused this, and in the same way have reduced the 

 patches at Cornbrook and Brown Clee from what they were as left 

 by the denudation in question. It is probable that the Cornebrook, 

 Clee Hill, and Shirlot districts stood above the level at which the 

 younger coals are formed. We find no older Coal-measures under- 

 lying the Carboniferous patch, at Cleobury Mortimer, for instance, and 

 thus the elevated strata have been exposed to all subsequent denuda- 

 tion, and would have given way to it had it not been for the capping 

 of Trap which has protected it. Seeing that at Little Wenlock, No. 

 17, we have the Pennystone protected from this more recent denuda- 

 tion by faults, and it is certain that the faults came after the 

 denudation of which this paper treats, I am inclined to think 

 the Coal-measures extended much more to the west, and that the old 

 line of erosion has been, with the Coal-measures, swept away by a 

 much more recent washing ; and it may be that some of the lines in 

 my plan on the west side may be due to these later destructions. 



A list of sections, in which the older series occurs from the horizon 

 of the Chance Pennystone downwards. 

 {Those which are numbered are shown on the map, PLATE V.) 

 2.GS:K..hectta,byDo„dy. 



3. Donington "Wood. \ 



4. New Hadley. f Geological Survey, 



5. "Wombridge. i Vertical Sections, No. 23. 



6. Nelson Pit, Prior's Lee (from Stone Coal). / 



7. Ketley. Prestwich, p. 445, " I am not aware of its existing further to the 



south than New Hadley and part of Ketley." 

 "Wombridge. Townson's Tracts. Vide Prestwich. 



8. Snedshill. Prestwich, p. 478. 



Edwards Piece, Hadley. Prestwich, p. 480. 



New Hadley. Prestwich, p. 481. 



Tub Engine Pit, Donington "Wood. Prestwich, p. 483. 



The following range from the Top Coal, Double and 

 Yard Coals, downwards : — 



9. Lawley and Steeraway. 



Horsehays. 



Rickyard Pit, Prior's Lee. 



10. Lawn Pit, Malinslee. 



11. Puddley Hill. 

 Portley Pit, Dawley. 



12. Deepfield Pit, Dawley. 



13. Madeley Court. 



14. Stafford Pit. Doody. 



15. Kemberton Pit. W. "Ward. 



Geological Survey, 

 Vertical Section, sheet 23. 



