October 6, 1916.

THE COLLIERY GUARDIAN

665

BRITISH ASSOCIATION.

(SECTION C : GEOLOGY.)

Presidential Address by Prof. W. S. Boulton, D.Sc., F.G.S.

If we attempt to compare the growth of applied
geology in Britain with that, say, in the United States
of America, or even in our great self-governing
Dominions, or to appraise the knowledge of and respect
for the facts and principles of geology as directly appli-
cable to industry in these countries and in our own, or
to compare the respective literatures on the subject, we
shall have to confess that we have lagged far behind
the position we ought, by right of tradition and oppor-
tunities, now, to occupy. The vast natural resources of
the countries named have doubtless stimulated a corre-

spending effort in their profitable development. But,
making due allowance for the fact that Britain is indus-
trially mature as compared with these youthful com-
munities, we cannot doubt that in this special branch
of geology, however splendid our advances in others, we
have been outstripped by our kinsmen abroad.

To attempt an explanation of this comparative
failure to apply effectively the resources of geology to
practical affairs would demand a critical analysis of the
whole position of science in relation to industry and
education which is being so vigorously debated by public
men to-day. It is unquestionably due, in no small
measure, to our ignorance and neglect of, and conse-
quent indifference to, science in general, more espe-
cially on the part of our governing classes. This war,
with all its material waste and mental anguish, may
bring at least some compensation if it finally rouses us
from complacence and teaches us to utilise more freely
the highly trained and specialised intelligence of the
nation.

The Geological Survey.

In any discussion of the present outlook of economic
geology in Britain we naturally turn first to the work
of the Geological Survey. When in 1835 the National
Survey was founded with De la Beche as its first
director, it was clearly realised by the promoters that
its great function, was to develop the mineral resources
of the kingdom, which involved the systematic mapping
of the rocks, and the collection, classification, and -u.
study of the minerals, rocks, and fossils illustrative of h
British geology. For upwards of eighty years this	---------—— -----------------

work, launched by the enthusiasm and far-sightedSBut, as,.the	coalK fields become opened up and

• p -ta ini i i	Li x-j	gradual Iv Pxha.mtpzi. the. nneistinn nf t.hA cait-vp-v end

genius of De la Beche, has been nobly sustained; and itM
would be difficult to name a Government service inf®
which the officers as a body are more -efficient or moreffl
enthusiastic in their work.	W

The time seems opportune, however, when weM
may ask whether the Survey is fulfilling all the func-ffl
tions that should be expected of it; whether it is ade-||
quately supported and financed by the Government;®]
whether it should not be encouraged to develop alongr
lines which, hitherto, from sheer poverty of official
support, have been found impracticable.	I I

It will be admitted that the re-mapping of the coal] |
fields, which were originally surveyed on the l-inch| [
ordnance maps more than half a century ago, before |
much of the mining information now available could be j
utilised is a primary duty and a pressing public n6“s-Lfpopular imagination, partly because of its proximitv to
sity. But it would be a great mistake to allow other MLondon, and its distance, amid England’s forest warden,
areas which have apparently little or no mineral wealth, W
and are destitute, so far as we at present know, of any|||
geological problem of outstanding interest, like theH
problem of the Highland schists, to remain, as at™
present, practically unsurveyed. Take, for example,
the great spread of old red sandstone in South WalesW
and the border counties of England, which on the J
present Government maps is indicated with a singleg .
wash of colour, and here and there an outcrop of corn-11
stone. It is true that the southern fringe of this areal i	Ww*lUs wuuvu

has been recently surveyed in more detail in re-mappingM For the uitimate solution of this problem an appeal
the South Wales coal field; but there remain upwards104will have to be made to many geological principles of
of 2,000 square miles of old red sandstone unsurveyed.Wwhich the high theoretical interest is universally
A map indicating merely the outcrop of the main bands 'acknowledged, although their practical importance is

of 2,000 square miles of old red sandstone unsurveyed.’8Kwhich the high theoretical’ interest is* universally
A map indicating merely the outcrop of the main bands Mlacknowledged, although their practical importance is
of sandstone, conglomerate, marl and limestone would iF;U0,t so immediately apparent. Thus the minute zonal
.. j 'work in the chalkj the laboilioug studies amo,ng jurassic
’ ammonites, as well as the detailed investigations of
minor transgressions and non-sequences in the mesozoic
rocks generally, will all have their value when estimating
the nature and thickness of cover over the buried coal
measures.

be of great assistance to engineers in such works as
water supply and sewage, as well as to agriculture.
Many other areas more clamorously demanding a
survey could be cited, but this example is given because
it happens that a few months ago the Survey maps of*
the area were found to be useless for the purposes of an

engineering work which has necessarily to be based upon
the local geology.

It is sometimes said, and with truth, that the great
function of a survey is to produce a geological map which
should be a “ graphic inventory,” so far as its scale
permits, of the mineral resources, actual and potential,
of a country. After all, such a map, even when accom-
panied wi'th its horizontal section and used by the trained
geologist, is a very imperfect instrument by which tc
summarise and accurately to interpret the results of the
surveyor’s work. There is so much to express that a
single map will not always suffice. It may be desirable
to show, not only the outcrops of the strata at the
present surface, but the thickness of the beds, and even
the shape of a buried landscape or sea-planed surface,
now unconformably overlaid by newer rocks. That the
Geological Survey are alive to the importance of such
work is shown by some of their recent publications. The
memoir on the “ Thicknesses of Strata in the Counties
of England and Wales, exclusive of Rocks Older than
the Permian,” published this year, is a most valuable
compilation, bringing together officially for the first time
a vast amount of useful fact, mainly from open sections
and borings. May we not look forward to the time when
the Survey can issue maps with “ isodiametric lines ”
showing the thicknesses in the case of important beds;
for example, sheets of productive coal measures, w ater-

bearing beds, and so forth? In any case, we may confi-
dently expect maps that will show by contours the shape
and depth of those buried rock surfaces, whether uncon-
formities or otherwise, which limit strata of peculiar
economic value. The director of the Survey has already
given us a foretaste, in his valuable and suggestive maps
of the palaeozoic platform of South-East England, and in
the contoured maps of the base of the keuper and of the
permian to the east of the Yorkshire, Nottingham, and
Derby coal field, and the rock surface below sea-level in
Lincolnshire.

During the last few months a series of much more
important publications by the Geological Survey has
appeared, viz., “ The Special Reports on the Mineral
Resources of Great Britain,” of which some six volumes
are completed. The Survey is to be congratulated upon
starting a line of investigation and report which is a
return to some of its oldest and best traditions.

At a meeting of the Organising Committee of this
section in February last, the following recommendation
was sent to the council of the British Association :—
“ In view of the numerous important instances which
have been brought to its notice of the exploitation in
alien interests of minerals in the British Empire, the
council of the British Association for the Advancement
of Science realises the national importance of preparing
for publication special reports on the mineral resources
of Great Britain, and recommends the extension of the
enquiry to the whole of the British Empire. The council
expresses a hope that it may be possible to expedite this
work by utilising the services of persons with expert or
special local knowledge. For this purpose an addition to
the annual vote for the Geological Survey would be
required. ”

It is gratifying to learn that the council has forwarded
this recommendation, with others, to the proper Govern-
ment authorities, and we may hope that adequate
facilities will be given to continue and extend this most
valuable work.

The Development of Concealed Coal Fields.

We will now consider what is, or should be, another
phase of the work of our National Survey, namely, the
discovery and development of concealed coal. beds.

The Royal Coal Commissions, of 1866 and 1901, and
frequent ^addresses and reports by leading geologists in
recent years upon the extension of our coal fields under
newer rocks, bear witness to the sovereign importance of
this branch of economic geology. One after the other the
coal fields are being re-mapped by th© Geological
..Survey, and we confidently expect the work to continue.

^gradually exhausted, the question of the survey and
■iMdevelopment of concealed coal fields becomes ever more
impressing and vital to our position as a great industrial
^nation.

[ In the Yorkshire, Nottingham, and Derby coal field
[the rapid extension of workings eastward under the
permian and triassic cover during recent years has been
[remarkable; and although the estimates of its buried coal
[measures adopted by the Commission of 1901, at that
|rime thought conservative, have since come to be
[regarded as too liberal, we may still rely upon a buried
[field of workable coals larger in area than the exposed
hoal measure ground of this great coal field, so that the
whole combined field will prove the richest in our
islands.

The Kent coal field has made a peculiar appeal to

I London, and its distance, amid England’s fairest garden,
from the great and grimy industrial areas of the North.
A recent address by Dr. Strahan vividly describes the
rapid exploitation of this field.

A problem of perhaps wider geological interest than
that of the Kent coal field, and certainly of greater com-
plexity, and containing the possibility of an even richer
economic harvest, is the occurrence of buried coal
measures under the great sheet of red rocks between
the Midland coal fields, and under newer beds in the area
to the south and east of them, towards London.

But the shape and structure of the buried palaeozoic
foundation of East and South-central England, with its
possible coal basins, is a more difficult because a more
obscure question. It has already claimed the serious
attention of geologists, and will doubtless demand in the
near future a more rigid and exhaustive study.

One obvious line of attack is the more intensive study
of the structure of the exposed coal fields, which is made
possible by our ever-widening knowledge obtained
largely from coal workings, present and past.

Stress may here be laid upon a great and needless loss
of valuable and detailed knowledge of our coal measure
geology. It is well known that the Home Office regula-
tions demand that plans of workings in the different
seams at a colliery shall be made and maintained by the
colliery officials; and that on the abandonment of the
mine copies of such plans shall bo kept at the Mines
Department of the Home Office for future reference. For
ten years, however, they are regarded as confidential.
Such information is recorded primarily with a view to
the prevention of accidents due to inrushes of water and
accumulations of gas.

Unfortunately, as mining men can testify, the plans
are often woefully incomplete, inaccurate, and positively
misleading as regards such features as faults, rolls, wash-
outs, and so forth, and this is notoriously so along the
margin of the plans where workings have been aban-

doned. Cases have been brought to my notice where
plans of old workings have been consulted when adja-
cent ground was about to be explored, and subsequently
the plans have proved to be grossly inaccurate, with the
consequent risk of serious economic waste. This unfor-
tunate state of things is partly the effect of the com-
plete official severance of the Geological Survey and the
Mines Department of the Home Office. When the
Geological Survey was first established, and for many
years afterwards, a mining record office for the collection
and registration of all plans relating to mining operations
was attached to it; but subsequently the mining record
office was transferred to the Home Office.

It ought to be made possible for all mining plans to be
periodically inspected by Government officials with
geological knowledge, not merely -after the plans are
deposited in a Government office, but during the
working of the mine; so that, if desirable or necsesary,
the geological facts indicated by the mine surveyor on
the plan can be tested and verified. If accurate and
properly attested plans of old workings were always
available, the opening up of new ground would be greatly
facilitated and much waste of time and money would be
avoided.

Visible and Concealed Coal Fields in the South Midlands.

In touching upon this question of possible buried coal
fields in the South Midlands of England, there are a
few points connected with our detailed knowledge of
already explored coal fields which must be taken into
account. They may be grouped under two heads :—

(1)	The stratigraphical breaks which are said to
exist within the coal measures themselves; and

(2)	The post-carboniferous and pre-permian folding,
and its relation to pre-coal jneasure movements.

Geologists who have made a close study of the detailed
sequence of any British coal field are fairly agreed that,
while sedimentation was accompanied by a general sub-
sidence, the downward movement was discontinuous,
possibly oscillatory, as evidenced, on the one hand, by
the occurrence of marine bands in a general estuarine
series; and, on the other hand, by those coal seams,
particularly, which consist of terrestrial accumulations
of plant material. But on a critical analysis of preva-
lent views, we meet with considerable difference of
opinion as to the inferences to be drawn from the known
facts.

Jukes-Browne regarded coal measure time as a period
of internal quiescence, in which terrestrial disturb-
ances were at a minimum. Another high authority said
” The coal measure period as a whole was one of crust
movement.” Dr. Gibson, after a detailed survey of the
North Staffordshire coal field, where the middle and
upper coal measures are fully and typically developed,
asserted that ” no break has been detected in the coal
measure sequence,” and a like conclusion is to be drawn
from the work of the Government surveyors and from
borings in the Yorkshire, Derby, and Nottingham coal
field, and that of East Warwickshire. Mr. Henry Kay
would fix a local unconformity at the base of the Hales-
owen sandstone of South Staffordshire, and another at
the base of the Keele beds (or so-called lower permian
marls); while in the Ccalbrookdale coal field the well-
known Symon fault, described by Marcus Scott as a
great erosion channel in the middle or productive
measures, subsequently filled up by the unproductive
upper coal measures, was interpreted by W. J. Clarke
in 1901 as a pronounced unconformity, a view which
has been generally accepted ever since, and which was
eagerly seized upon by those who hold that the Mal-
vernian disturbance occurred at this time.

The inter-relation of the divisions of the coal measures
is, in view of the search for hidden coal fields, so impor-
tant that we may pause for a moment to consider the
significance of the evidence for this unconformity which
is said to exist in the Midlands between the middle and
upper coal measures.

The plate which illustrated Marcus Scott’s paper on
the Symon fault, showed the upper beds plotted out
from the lowest workable seam in the older measures,
which he assumed to be horizontal (their original posi-
tion); while Clarke, using Scott’s data, plotted his sec-
tions from the base of the upper measures, which he
used as a horizontal datum line. In both cases the
sections were drawm with a much-exaggerated vertical
scale, and, of course, correspondingly exaggerated dips.

Both these interpretations are misleading (apart from
the question of scale), because in neither case is the
adoption of the horizontal datum line strictly justified
by the facts. In the one case the curvature of the
basin is made too great, and, in the other, the dips in
the middle measures are unduly increased; for, as
mining plans show7, the base of the upper measures is
by no means horizontal. The fact is that the undula-
tions in the measures throughout the coal field are
extremely slight, there being scarcely any perceptible
dip in the strata, as noted by Scott, except near what
is called the “ Limestone fault,” where the dips, as will
presently appear, can be otherwise accounted for.
Furthermore, there is a significant absence of faults
other than those which affect middle and upper measures
equally.

There is another and a simpler explanation of this
classic disturbance, and one which harmonises, in part,
the view’s of both Scott and Clarke; and at the same
time helps to give us a reasonable interpretation of the
apparently conflicting statements which have been made
by working geologists respecting the relationship of the
coal measure divisions in the Midlands.

The keuper marls of the Midlands occur either in
horizontal or very gently undulating sheets, but Dr.
Boswrorth has shown that around Charnwood Forest they
dip in all directions, “ sometimes to the extent of 20
or even 30degs.,” and that everywhere the inclination
is in the direction of the rock slop© beneath, though
ahvays at a smaller angle than the slope. This local
dip (or ” tip,” as he calls it) “ seems most likely to