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Weymouth Distent
I Sandsfoot Xo8v II Osmington
III Milwtstiuly
Corallian Rocks of Encland.
TabU of Comparative Sections by the Bev. J.F.Blake, MAE G.S, and W. H. Hudleston Esq.MAJF.GS.
North Wilts . Berks , and Oxfordshire Range Cambridgeshire
Quart Jem
The York's In
V Westbwy
■
VI Calne
I'll HighworOb.
IX Upwart
n .'. . .
X -V Grimstcn
■ .v 5y W.
XI Malltm .17/ llamhlrton XIII Nrivlnndale XIV fbiyi Vullet
, , Explanatory Notes.— These sections, with the exception of No. 7, give the full development
of each tied along a surface line earymg from a few hundred yards to a distance, in the case of No. 12, of eight
imhs. As most of the Corallian beds, taken on a large scale, are wedge-shaped, the real thickness of each bed varies
materially according to (hi point SI I. ct, d. Tims in the case of So. 7- A ction at Highicorlb—llte entire series shrinks
within a moderate distance in a southerly direction, to about 30//. with a complete extinction of some beds and an.
increase of others '
The arrangement adopted brings the top of the chief limestone series of each section upon the same heel
throughout, and thus enables an estimate to be formed at once, both of the relative volume of the limestones in each
and also of the respeelnr derclopmeut of the I 'ppi r and Lower Groups.
The Upper Group is usually a reddish calcareous grit irith variable clays : it includes certain oolitic iron
or.; lias terrumiwus character may be noted in those parts „f the Berks-Oxfordshire Ranqe not shown in the
'mio Titer Calcareous Grit
The Middle Group comprises the ^OBIGEMMA-flL, where that rock is developed, and the various lime-
mi or underlie d— sometimes m a double serirs.lt includes the Coral Rag and Cobmjjbk
, , . ' S ' ah . °J II f""' y* and days; in the West Midland, to a large extent,
of bosuh sand; whilst in ) orkshtre it is represented by a great ,/nckness ofsolidslone.lt includes the Lower
Calcareous Grit.
Notes on die Separate Sections.— I. is a vertical rendering of die roast section he/uren the points named, a
distance of H m ; it represents the development of the series on the' south side of the Weipnonth anticlinal. II. is a
aenernli-ed section of the cliff on the opposite side of Weymouth Bay, 3£ m. N.E. of Nothe 1'omt, and on the north side of
the M'eumouth anticlinal: III. Abbotsbury, also on the north side of die anticlinal, is 10 m. W. by N. of
i ..niin, •/. .« Mill i" the direction of the strike : the section is partly composed from the exposures on Linton Hill (see
Fig. I ). IV. is drawn principally from the tectum m We railway cutting: in the northern portion of 'the district
the Loirer Group is better exposed. V. is- drawn from exposures in or near tlie Ironstone workings, and, from
ifo, 'motion reattributed bi/ the manager. The iron ore it only 2 //. thick at a boring between the workings and the
urn VI is a vertical rendering of the section from Conygre marry to the east side of Calne, distance \. m. :
' Boioood Park. No. 2 is not well exposed. Beta
town.
the Loirer Group has probably more
this line
and Waotton Bassett a thin representative of the Upper Group is occasionally seen. VII. is a vertical section. No
good emosure of Ko. 6. YliX.No Upper Croup in this locality : the Middle ar Limestone Group is inconstant.
IX About Oft of beds are proved in th, -oath pit. X. is a vertical rendering of the surface section from N.
Gr'imstm to' Burdole, length 1100 yards (see Fig. 22 ). The sequence of 2, 3, i and 5 is proved upon the
escarZmt ■ that of 1 and'l on the dip slope. XI. is, to a certain extent, constructive : the sequence of 1 , 2 and 3
is lined on the east side of Malum ; that of 5 and 6 on the west side ; tin- exact relation of No. 4 to the Upper and
Lou; r Groups is »". guile dear. XII. is a vertical rendering of the surface section across the Hambleton massive,
lenath s m (see Fig.Vo) ; 4 and 5 vary greatly within short distances; the thickness of 5 is a presumed average
alma Ot actual line of section ; northwards it is 50 ft. thick, and southwards it has thinned out. XIII. gives the
,1. r I. out of the series as shoivn in a transverse valley about the centre of tlie Tabular Chain: the lower part of
l\^eTthi"ThTOStler,-here only i ft. thick. XIV Another transverse valley, 5 m. from the coait the