David Woolacott — Borings at Cotefield Close, etc. 163 



III. — On Borings at Cotefield Close and Sheraton, Co. Durham 

 (Permian and Coal-measures). 



By David Woolacott, D.Sc, F.G.S. 



DURING the last year I have examined, through the kindness of 

 Mr. E. 0. Forster Brown, Ein. Eng., borings that have been 

 put down by Messrs. Bell Bros., at Cotefield Close and Sheraton, 

 near the southern limits of the Northumberland and Durham 

 Coalfield. They are situated about 5 miles west of Hartlepool, and 

 about 8^- miles east of the Permian escarpment at Ferryhill. The 

 boring at Cotefield Close lies about 1^ miles east of Hurworth Burn 

 station, and about the same distance south of that at Sheraton. 

 The details of the former are from my own notes which were taken 

 when the hole was finished, but those of the Sheraton cores are by 

 Dr. C. T. Trechmann, who examined them as they were brought up 

 from time to time, it thus being possible to obtain a very full record. 

 I also desire to thank this geologist for some notes on the Sheraton 

 boring which are incorporated in this paper. Both of the boreholes 

 passed through the superficial deposits and Permian strata into the 

 Coal-measures, but as that at Sheraton has just entered the last- 

 named series and is not yet completed, the remarks on the 

 Carboniferous rocks refer only to the strata pierced at Cotefield 

 Close. The examination of these cores adds to our knowledge of 

 the Permian, confirming some of the points that Dr. Trechmann and 

 I have enunciated in previous papers dealing with the Magnesian 

 Limestone. The boring at Cotefield Close is also of interest because 

 it penetrated the Lower Coal-measures beneath the Brockwell Seam 

 and gives a section of the little-known Ganister Series. It is hoped 

 in a subsequent note to deal with any noteworthy features that may 

 arise in connection with the Carboniferous rocks of the Sheraton 

 borehole. 



It is known that the Coal-measures in the south of Durham rise to 

 the south beneath the Permian and are cut by the Butterknowle 

 fault, which throws them down to the south so that a small area of 

 northerly and steeply dipping measures lies on the south of this 

 fracture. 1 It was to obtain the limits of this area, which has been 

 proved to contain workable coal at Fishburn and Trimdon, that the 

 Cotefield Close boring was put down, while that at Sheraton was to 

 get information regarding the nature of the coalfield to the north of 

 the fault. 



As the particulars regarding the boreholes will doubtless in the 

 course of time appear in the volumes of the Borings and Sinkings of 

 the North of England Institute of Mining Engineers, it is not 

 proposed to give the minute details regarding each bed, but to 

 describe the general characteristics of the strata and discuss the 

 points of geological interest. In many cases it is impossible to give 

 the exact thickness of a bed as only the more solid portions were 

 brought up in the core, the softer granular beds being ground down. 



1 Sections of The Coal Seams of Northumberland and Durham Coal-field, 

 by J. B. Simpson, 1877 ; section in Lebour's Geology of Northumberland and 

 Durham, 1886, etc. 



