THE OCCURRENCE OF QUARTZITE BOULDERS IN THE STANLEY MAIN COAL AT NOSTELL, NEAR WAKEFIELD

Abstract

The Main or Priory Coal and the Lime Coal, the lower and upper parts of the Stanley Main Coal, are worked in Nostell Colliery (Edwards and others, 1940). The former is about 3 ft. thick. A fine specimen of a quartzite boulder has recently been found in the coal of the Priory Seam. It weighed 40 Ibs. and measured 9 ins. by 6 ins. Several smaller ones, weighing about 5 to 6 Ibs. each, have since been found in the same area which is 440 yds. N. 30° W. (true) from the downcast shaft and 400 yds. below the surface. The large boulder was found in the actual coal about 2 ft. down from the roof and the smaller ones were found in the same seam, some in the top few inches of coal and some near the roof of the seam. The area in which the boulders were found is associated with a large wash-out in the strata above the seam where, for over a distance of 40 yards, the so-called Lime Coal Seam, which is normally 8 to 11 yds. above the Priory Seam in this area, comes down to 3 or 4 ft. and, in addition, thickens, from a normal 2 ft., to 3 ft. The roof above the Priory Seam in this abnormal area, has a large quantity of fossil vegetation, remains of Calamites and vertical fossil tree trunks being abundant. The boulder is similar to those previously reported from coal seams in Yorkshire by Spencer …