149
XII.
Some Essex Well-Sections.
By W. Whitaker, B.A., F.G.S., Assoc. Inst. C.E.
[A combination of papers read before the Club on March 29th, 1884,
and February 26th, 1885.]
Having collected accounts of the sections of many wells in
Essex since the publication of the different Geological Survey
Memoirs that treat of various parts of the county, I have
thought that the Essex Field Club may be glad to have a
description of such of these as have not found a place in any
of those Memoirs, and are therefore left unprovided for, there
being no prospect of the publication of any other Memoir in
which they could appear.
With these are included an account of one section, which
differs in some particulars from that already published, and
of two others, taken from published sources, which are not
likely to be generally accessible. I likewise give particulars
of some old wells, recorded in the MSS. of the late Dr. J.
Mitchell, for the use of which I have to thank Professor
Prestwich. I have great pleasure also, in thanking the
engineers, well-sinkers and others, who have so kindly given
me information, especially as I hope for more.
Of two sections only is there need to make special remark.
The Loughton boring is one of the deepest in the London
Basin, and is the third in the county that, after passing
through the Tertiary beds, has pierced the Cretaceous beds to
the bottom of the Gault, the other cases being at Harwich,
and probably at Saffron Walden.
The Wickham Bishop boring, the deepest in the county,
is of great interest, as showing a very sharp fold of the beds
(?with a fault), so that the bottom part of the London Clay
and the Reading Beds have been passed through twice. Had
I not seen specimens from this boring, it would have been
M