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THE GEOLOGIST. 



BRITISH ASSOCIATION MEETING, 



THE BURNLEY COAL-FIELD. 



By Joseph Whitaker, Member of the Manchester Geological Society, and 

 T. T. Wilkinson, F.R.A.S., &o. 



Although of limited area, the coal-field of Burnley is uncommonly rich, not 

 only in its stores of fossil fuel, but also in points of stratigraphical interest, 

 and in organic remains. It comprises within itself a complete series of the 

 middle and lower coal-measures. 



It may be described as occupying a basin like a valley surrounded by high 

 ranges of hills, amongst the most prominent of which may be noticed Pendle 

 on the north, Boulsworth on the east, Gorple towards the south, and Hambleton 

 on the west, some of which rise to near two thousand feet above the level of 

 the sea. Geographically it occupies the lowest portion of the valley, geologi- 

 cally it is the highest, when considered with reference to the stratification of 

 the district. 



The most productive portion of the field underlies the town of Burnley, 

 where it assumes the form of a long trough, bounded on the east and west by 

 two lines of upheaval, running nearly parallel. 



The greatest depth to which the strata has been pierced occurs on the Ful- 

 ledge estate, where a depth of six hundred feet has been attained, and where 

 the following seams of coal have been found : — The Dog Hole Mine, or top 

 bed, six feet thick ; Kershaw Bed, three feet ; Shell Bed, two and a-half feet ; 

 Burnley Old Five feet, or main coal, five feet ; Higher Yard Bed, three feet ; 

 Lower Yard Bed, Low Bottom, or four feet coal ; Thin Coal, two and three- 

 quarters feet ; Great Mine, or Bing Bed, four feet. 



These are locally known as the Burnley "Top Beds.*' They include about 

 thirty-five feet of coal embedded in about six hundred feet of intermediate 

 strata. For a depth of about two hundred feet below these no coal occurs. 



Then come the Arley series, or Habergham mines, consisting of the follow- 

 ing workable seams : — The China Bed, two feet thick ; the Dandy Bed, three 

 feet ; the Arley or Habergham Mine, four feet ; giving a total of nine feet of 

 coal to about four hundred and forty -five feet of interposing strata. 



A series of strata devoid of coal of at least five-hundred feet in thickness 

 here again form another natural division of the measures, which is succeeded 

 by the Gannister series comprising a foot mine with a hard gannister floor ; the 

 Spa Clough Top Bed, two and a-half feet thick; Spa Clough Bottom Bed, four 

 feet ; or a total of about eight feet of coal with six hundred and eighty feet 

 of intervening strata. 



From the lowest coal of the Gannister series to the Rough Bock, or the 

 highest member of the Millstone-grit formation the distance is something over 

 three hundred feet. 



Hence, omitting many thin seams of less than a foot in thickness, there is, 

 from the highest mine of the Burnley measures to the highest member of the 

 Millstone-grit, an entire total of over fifty feet of coal for a depth of two 

 thousand and twenty-five feet of strata. The millstone grit series of coals 

 occur next in the descending order, consisting of three thin seams of less 

 thickness than one foot, none of which have been worked in the neighbourhood 



