CHAPTER II.

DESCRIPTION OF THE ROCKS.

The rocks, or geological formations, entering into the structure of this district are—

Secondary, or Mesozoic Formations. 1. The Lias.
2. The New Red Sandstone.

Primary,
or Palæozoic Formations
3. The Lower Red Sandstone, or Permian.
4. The Coal-Measures.
5. The Silurian Rocks.
Igneous, or
Unstratified Rocks.
Basalt and Greenstone.

1. The Lias.

Although not strictly lying within the district. I mention this formation because its existence in Staffordshire was first discovered during the survey of the coal-field, and because it may have a rather important bearing on some of the theoretical results arrived at. It occurs on the high ground of Needwood forest. It consists of alternations of blue shale and limestone, the bands of limestone being not more than 6 or 8 inches in thickness, over which are some arenaceous beds becoming in the upper part a white shaly sandstone. The limestone bands have not yet been worked, but they would probably have the same hydraulic character as those of Barrow-upon-Soar.[1] My colleague Mr. Howell, however, who mapped this neighbourhood, informs me that the limestone here is more argillaceous, and not so pure as the Lias limestone of other places, that near Stratford-on-Avon for instance. In the sandy beds are some imperfect casts of bivalve shells.


  1. My attention was directed to this Lias district by my friend Mr. T. Turner, of Abbotts Bromley, who had himself a suspicion of its true character from the observations of his friend Mr. E. Pickering.