NATURE 
ats 
THURSDAY, FEBRUARY 1, ro17. 
OIL-FIELD TECHNOLOGY. 
Oil-Field Development and Petroleum Mining. 
_ By A. Beeby Thompson. Pp. xix+648. 
(London: Crosby Lockwood and Son, 1916.) 
Price 25s. net. 
— is practically a second edition of the 
author’s previous volume on the same sub- 
ject, with transposition of the leading divisions 
of the title. It is, however, by no means a mere 
reprint, extensive alterations having been effected 
by correction, addition, and excision. Readers 
interested in some only of the many branches of the 
subject will doubtless consider that both the last 
two processes might well have been carried 
further, but an impartial survey of the work will 
show that the author is gifted with a judicious 
sense of proportion in the allotment of attention 
to the several sections of his complex topic, only 
stopping at the door of the refinery, the operations 
within which are beyond the scope of the volume, 
and are merely summarised in some half-dozen 
pages. 
Somewhat more than half the work is concerned 
with the technology of exploitation and transport, 
but a fair degree of consideration is accorded to 
the geological questions of the original formation 
of petroleum, its mode of accumulation, and the 
effect of tectonic movements. © The author naturally 
deals at greater length with the more important 
factors of composition and structure of strata, as 
affecting the concentration of oil, than with the 
more purely academic problems of the primary 
formation of the hydrocarbons from their parent 
organic matter, animal or vegetable. Ample space 
is, nevertheless, occupied by a careful balancing 
of the more or less contradictory evidence on this 
point, with a general deduction in favour of cata- 
lytic action by anaerobic enzymes shortly after 
inclusion in sediment. This provisional hypo- 
thesis obviates at least many of the objections 
which have been advanced against the more 
' vaguely enunciated theory of organic origin, now 
generally accepted. That this was ever .con- 
troverted is attributable to the absence of co- 
operation between geologists and chemists, so 
that wholly untenable hypotheses have been advo- 
cated or supported by leading chemists; not that 
there was any doubt whatever that petroleums 
had been produced synthetically in the laboratory, 
but that geological considerations precluded the 
acceptance of this as a natural method of forma- 
tion. The converse error, through geologists pro- 
posing chemical impossibilities, is probably rarer, 
though not wholly unknown. 
Apart from the question of origin, the texture 
and tectonic structure of the rocks of an oil- 
bearing region are shown to have a most important 
bearing on the productivity of the field. Not only 
do oil-bearing rocks, like all the coarser mechanical 
deposits, occur in lenticular masses, often. of 
very abrupt angles of attenuation, but even in 
continuous sandstones the porosity (and conse- 
NO. 2466. vor. 98] 
quent passage of fluids) may be largely reduced 
by calcitic or siliceous cementation, irrespective of 
the coarseness or fineness of the grains or pebbles 
composing the bulk of the -rock. Some very 
coarse conglomerates have been rendered wholly 
impervious by such cementation, occurring 
sporadically, and thus removing those portions of 
the rock from the category of productive ‘“ sands.” 
The migration of oil under pressure, generally 
with the aid of flexures, faulting, or other tectonic 
disturbance, is dealt with at length, as its im- 
portance merits, and is illustrated by heavy yields 
of oil from horizons wholly devoid of it except 
where forced into contact with productive members 
of the geological series. As the author remarks, 
erroneous deductions may easily be drawn from 
imperfectly studied phenomena. Our knowledge of 
the physics of the subterranean flow of oils is yet 
little more than the empirical record of observed 
details not permitting the formulation of anything 
beyond tentative proposition of working hypo- 
theses. The chief difficulty lies in the weight to be 
assigned to unknown quantities in the many 
relevant factors—pressure, gravity, capillarity, 
surface-tension, solution of gas in oils, effect of 
underground temperature on viscosity, original 
structure of the rocks, with its modification by 
tectonic action, by the disturbance of equilibrium 
in exploitation through the rapid removal of vast 
bulks of oil and sand, and to some extent by the 
vibration due to abrupt stoppages of the flow 
by temporary choking of the boreholes. 
Caution in the interpretation of surface indica- 
tions is enjoined rather as regards forecast of 
quantity and quality than as depreciating their 
value as guides to probable supplies, but oil-films 
on streams may be some distance from their 
source, or may arise from certain vegetable com- 
pounds. Films of iron peroxide, although in- 
stantly distinguishable by their incoherence, have 
often misled careless observers. 
The author purposely refrains from .entering 
upon. the exceedingly ‘intricate chemistry of 
petroleum beyond a very brief summary of the 
physical characters of a few typical oils. He 
shows that the supposed difference in original 
source hetween asphaltic and. paraffinoid oils is 
based upon inaccurate data, many fields yielding 
both classes, and frequently in admixture. 
The whole constitutes 4 useful treatise on the 
branches to which the author has devoted special 
attention, and the localities cited.in illustration are 
mostly those of his personal investigation. 
The orthography of Russian and other place- 
names is often open to individual choice, and there 
are. few real misprints, such as “menelite.” Prof. 
Mrazec’s term “‘diapir” (for masses of older rock 
forced up through softer strata) should not be spelt 
“diaper.” . “Commendable criticism” (p., 125). is 
clearly a slip. for. “commendatory criticism.’’ In 
the footnote on p. 116, XII. should be LXI. Inthe 
index are several unimportant errors, not affecting 
position, but Ackverdoff for Akhverdoff may be 
noted, and Quayaguayare would be more serious 
were not Guayaguayare given in its right place. 
Z 
