112

THE COLLIERY GUARDIAN

July 21, 1916.

were enabled to locate their position. They had then
sunk 800 yds., landing at the point marked P on the
section. But irrespective of any fossils, they could
really correlate their seams with those of Shropshire,
north of Coalbrookdale. They could not correlate with
Coalbrookdale, because Highley was the first point of
correlation. He was entirely in agreement with Dr.
Arber as to the north of Colwich. There was no corre-
lation by seam as between the northern part of the
Shropshire coal field and Cannock Chase—certainly not
!as regarded Shifnal and the Wellington part of the field.
From the western side, his (Mr. Forrest’s) firm had
proved, driving westward, but did not meet with, the
silurian bank in the position the author had shown it.
Another point on which he would like to ask Dr. Arber’s
opinion was whether the Silurians were found heavily
charged with water. In the Cannock Chase coal fields,
wherever they got into the Silurians, they always got a
head of water; but 'there were parts of the coal field
where the Silurians were not so charged. In one area
there was a double fault : one at a depth of 120 yds.,
and the other at 360 yds., and he came to the conclu-
sion that it would be perfectly safe to drive in between
the faults. At the upper fault they got 2,000 gals, per
minute of salt water. That was a costly and trouble-
some experience, but it was clear there was a division,
and at a certain point much below the salt water emis-
sion they were quite dry. He would not be surprised
if the silurian bank was cut off in the east; but from
that fault to the eastern side he believed there was a

Horizons.		Warwickshire.	South Staffordshire.	Wyre Forest and Coalbrookdale.
? Stephanian 			Enville series (Corley and Kenilworth beds) (Red unproductives)	Enville series f Clent group (Romsley „  (Red unproductives)	Enville series  (Red unproductives)
Upper coal measures			Keele series Red unproductives)	Keele series (Red unproductives)	Keele series (Red unproductives)
Westphalian.	Transition coal measures	Haunchwood sandstones  Nuneaton clays (Red-grey unproductives)	A Illey group Halesowen ) Hasbury „ series	) Halesowen group  IWitley Red clay series (Red-grey unproductives)	Sulphur coal series  (Red-grey productives)
	Middle coal measures ...	Grey productives	Grey productives	Sweet coal series (Grey or red-grey productives)
	LLower coal measures 		Absent	Absent	Absent

very large tract of valuable ground—miles of it. Pro-
bably the coal measures would be found upside down,
rolled in and out. It was clear there was no correla-
tion between the Wyre Forest and South Staffordshire.
If the study had been carried further north, it would
have been still more useful, since the coal field there
had more chance of being productive than that further
south. With regard to the Bentley fault, it would be
interesting to know whether that fault was a continua-
tion of the one through the back of the western coal
measures, and dividing the Thick coal measures from
the Cannock Chase measures on the western side of the
Cannock Chase coal field. There were indications of an
obvious jumble on the western side, and between the
Wyre coal field at Highley and North Staffordshire there
were some conditions which appeared to bear out entirely
the theories of Dr. Arber. In North Staffordshire the
measures dipped to south-west, and at one point there
was a depth of 760 yds., whilst very much farther north
the depth was 380 to 480 yds. If the fault continued,
it would throw up those measures.

The President suggested that, in view of the some-
what complex character of the paper, it would be well
to defer the discussion to the next meeting, on
October 16. He proposed a hearty vote of thanks to
Dr. Arber.

Mr. Forrest seconded, remarking that the paper had
been of the greatest value to himself.

The resolution was carried with acclamation.

Dr. Arber, acknowledging the vote, thanked the
meeting for its kind reception. The first point to deter-
mine was whether the coal field was anticlinal or
synclinal. If it was synclinal they might accept what
he had put before them. He would be glad to have any
suggestion that would assist in elucidating the points
raised. The whole point of the horst was that nothing
was pushed up; the other portions were pushed down.
The boundary fault was an extremely complicated
question, because those faults were double in many
cases. It was quite true that the silurian banks looked
very near, but the only case where they were sure of the
location was that of Claverley, coming from the western
measures to South Staffordshire. With regard to the
Bentley fault, the matter was not quite simple, because
there was a fold there as well. The explanation of the
Cannock Chase coal field given by Jukes would have to
be abandoned. Mr. Kay, his colleague, hoped some
day to elucidate that fault.

Grimsby Coal Exports.—The following quantities of coal
have been exported from Grimsby during the week ended
July 14:—Foreign : To Dieppe, 883 tons; Dunkirk, 667;
Esbjerg, 1,230; Gravelines, 67; and Treport, 135 — total,
2,982 tons foreign, against 12,426 tons during the correspond-
ing week of last year.

STRUCTURE OF THE SOUTH STAF-
FORDSHIRE COAL FIELD.*

By. E. A. Newell Arber, M.A., Sc.D., F.G.S.
Introduction.

Dr. Arber stated that for some years past he had been
engaged on special studies of the South Staffordshire
coal field and the adjoining coal fields of Warwickshire
and Wyre Fore st-Coalbrookdale. The purpose of these
investigations was firstly to determine which palaeo-
botanical horizons were represented in each field, and
thus to institute the standard of comparison between
them. The results obtained by this method had been
already published by the author in the case of the Wyre
Forest and South Staffordshire coal fields, and by his
former pupil, Mr. R. D. Vernon, in the case of the
Warwickshire area. This work has been reviewed here
with special reference to the points which still remained
in doubt. In the present paper, Dr. Arber also proposed
to consider the general geological conclusions which
result from this work, in particular from the more recent
study of the South Staffordshire coal field. These con-
siderations included a discussion on the original relation-
ship of these coal fields, and on the nature of the con-
cealed ground between them, and were therefore of
importance from the industrial standpoint. The follow-
ing table summarised the development and the palaeo-
botanical horizons met with in each of the three fields
so far as they were known.

It would be seen from the above table that the litho-
logical development of the measures in Warwickshire
and South Staffordshire were very similar, but that the
Wyre Forest-Coalbrookdale field differed from the others
in the fact that the transition coal measures were pro-
ductive, and that, in some of the Welsh borderland
fields, the middle coal measures were a red-grey, whilst
in others they were a grey series.

Dr. Arber pointed out that on this question of rela-
tionships he had arrived at conclusions which were
diametrically opposed to those which constituted the
accepted explanation at the present time. He had ven-
tured to add here an alternative hypothesis.

He wished to express his indebtedness to many
friends, particularly in South Staffordshire, who had
assisted him in the matter of the geological or topo-
graphical information. In this respect he particularly
desired to express his thanks to Mr. Henry Kay, F.G.S.,
of Birmingham; to Mr. W. Wickham King, F.G.S., of
Hagley; and to Mr. H. W. Hughes, F.G.S., of Dudley,
to whose unrivalled knowledge of the field he was
greatly indebted.

The Lithological Succession in the South Staffordshire
Coal Field.

The two-fold grouping of the measures into a lower
productive and an upper unproductive series was a
perfectly natural one. By the latter term, however, it
was not implied that coal seams were entirely absent.
Coals did occur on several horizons in these beds, but
they were few in number, and never of sufficient thick-
ness to be of any economic importance. The two series
were further contrasted as regards the dominant colours
of the sediments. The lower productive sequence was
a grey series. The upper division consisted of a lower
red-grey group, in which red alternated with grey rocks,
and a higher division wholly red in colour.

As to these facts, there was no dispute, though much
doubt and difficulty had existed for many years past as
to how much of the unproductive series was of carboni-
ferous age, and whether part at least of it should not be
relegated to the permian. These were questions which
would be discussed here in some detail. The following
was the grouping which had been adopted, and would
be defended in the present paper :—

(a) The Enville Series. — The points in which the
above classification differed from the schemes previously
put forward, was firstly in the inclusion of the whole of
these measures in the upper carboniferous, and secondly
in the nomenclature applied to the highest beds. It
was a perfectly conformable series throughout. The
red clay series of Jukes was followed by the Halesowen
series, and then the Keele group. These terms had all
been in use in South Staffordshire for some years past.

* From a paper read before the South Staffordshire and
Warwickshire Institute of Mining Engineers.

The sub-division of the Halesowen series adopted here,
was in the main that recently advocated by Mr. Kay.
Still further to the south, higher beds, which reached
their maximum development in the Enville district of
Shropshire, followed conformably on the Keele group.
These were usually termed the middle and upper divi-
sions of the Salopian permian of Hull. For reasons
which would be fully discussed at a later stage, in this
paper, Dr. Arber regarded these as probably Stephanian,
and not permian, in age. It had seemed to him advis-
able, since the term “ Salopian ” was so intimately
connected with the word “ permian,” to apply some
other name to these beds, which should be non-com-
mittal as regards geological age. It might be appro-
priate to institute the term ” Enville series ” for these
sediments, and thus associate them with the region
where they attained their maximum development. The
two local sub-divisions of the Enville series might be
also conveniently named after the localities in which
they were best known in this coal field, namely, the
trappoid breccia (part of the upper Salopian permian) of
the Clent Hills as the Clent group, and the calcareous
group below it (the old middle permian) resting on the
Keele series, as the Romsley group. These two terms,
however, were only intended to be names of purely local
significance, confined to this field.

The precise age of the Enville series was still very
difficult to demonstrate. Despite repeated endeavours
on the part of the author and others, it had not so far
been found possible to obtain sufficient palaeontological
evidence. As regards the Romsley beds, the only fossil
which had ever been obtained from these beds in the
southern area, as the result of the labours of a large
number of previous workers, was Spirorbis, a genus of
wide vertical, and lateral distribution in the Midlands.

A study of the red ground to the south of the visible
field had, however, convinced the author that the Keele
and Enville series were intimately related, forming
everywhere a perfectly Conformable graded sequence.
He was also quite convinced that these measures were
all of the same geological age, though they did not neces-
sarily all belong to the same horizon. If the age of one
series could be shown to be carboniferous, as he believed
it could, then, in his opinion, the whole was an upper
carboniferous and not a permian sequence. This was a
vexed question on which much had already been said.

When we turned to the eastern border of the field, we
found further data. The beds passed through in the
shaking of the Hamstead Colliery, between 1,008 and
1,233 ft. from the surface, were the equivalents of the
Keele series of the southern extremity of the field. From
these red rocks in 1888 Dr. Kidston described a series
of plants forming an undoubted upper coal measure
assemblage.

Further, from the Great Barr Quarries, close to Ham-
stead Colliery, Mr. Hardaker had recently described both
plant remains and footprints. These fossils were
admittedly from a higher level than the Keele group
penetrated in the colliery sinking. The rocks consisted
of marls and sandstones with conglomerates, and they
underlay breccias. They were thus clearly the exact
equivalents of the Romsley group of the southern part
of the field. The plant remains consisted of Walchia
piniformis (Schl.), Walchia imbricata (Schl.), and
Artisia (Sternbergia) sp. In addition, 11 types of foot-
prints were described from these beds. Mr. Hardaker
had no hesitation in regarding these beds as representa-
tive of a part of the Rothliegende of Germany—that is to
say, the Hamstead Quarry series must in the future be
definitely regarded as of lower permian age.

Here we had a further, 'and quite recent, support for
the attribution of these beds to the permian rather than
the carboniferous, and one which was particularly
important, since it was based on palaeontological
evidence. In the author’s opinion, however, no such
conclusions could be safely drawn from these fossils.
He more than doubted whether any of them were of
value, as indicating any one of the following horizons in
particular, viz., Westphalian, Stephanian, lower or
middle permian. It had yet to be proved that any of
these fossils were confined to the lower permian, in
which, however, there was no dispute that they may
occur.

But the matter did not rest there entirely. The
Romsley beds of South Staffordshire were admittedly
accumulations of a desert type, and in such, as was well
known, fossils were comparatively rare. It was a
matter of common observation that, in desert accumu-
lations of the permo-carboniferous age (whatever horizon
they might belong to), the commonest fossils were often
members of the genus Walchia among plants, whilst
the associated traces of animals were chiefly ichia, or
footprints. The occurrence of such fossils in the
Romsley beds was exactly what we should expect to
find in such a red series, and they fold us nothing as to
the true horizon. The abundance of Walchia. to the
exclusion of other plant types, in the true Rothliegende
of the Continent was another standard example.
Walchia seemed to have been a type of conifer, which
flourished well under desert conditions, though it also
no doubt managed to exist under other environments.

Mr. Cantrill had discovered Spirorbis in this series in
the southern region of the field. The author had else-
where dealt at some length with the distribution of this
fossil in the British carboniferous rocks, and had pointed
out that, while this fossil was often particularly abun-
dant in the transition and upper coal measures of this
country, it really occurred throughout the whole of the
carboniferous, and was therefore of no real value as a
stratigraphical index. At the same time its occurrence
in the Enville series was in favour of a carboniferous,
rather than a permian, age being assigned to these beds.

(7>) The Keele and Other Scries.—With regard to the
pahrbotanical horizons of the Keele, and the measures
beneath that series, there was now no uncertainty. In
his most recent memoir on the subject. Dr. Kidston has