Evening star., 1940-05-21
Of Sturs, Men
And Atoms
Notebook Of Science Progress
In Field. Laboratory
And Study
By Thomas r. Henry.

And Study
By Thomas r. Henry.
A hitherto unopened record Of the
vicissitudes Of the earth through thou
sands Of milleniums, obtained by shoot
ing holes in the bottom Of the sea, now
is being deeoded by geophysicists Of
the Carnegie Institution of Washington.
Undoubtedly the best preserved
manuscript" of the past before man
appeared on earth, the floor Of the deep
ocean under more than a mile of water
remained impenetrable until four years
ago, when Dr. Charles S. Piggot Of the
Carnegie staff invented depth gun
which fires automatically when 1t
reaches the bottom and plunges hollow
cylinder into the debris Of ages. The
cylinder closes automatically. Attached
to cable, it is hauled to the surface,
bringing with 1t long core every inch
OF which contains, if it can be read, the
story of many centuries.
Narrow strips of sand and sharp peb-
bles in these cores constitute record Of
four long ice ages. These must have been
brought originally from the land. The
only way such heavy terrestrial ma
terial could have gotten so far to sea
was in icebergs broken off from glaciers.
Strips composed of closely packed fine
dust indicate two or three periods Of in
tense volcanic activity on land. The
dust was blown to sea by the winds.
Tiny specks of iron in the deposits
give continuous story of the direction
of the compass millions of years ago.
Each particle acted as miniature COM
pass needle. AS it sank very slowly
through the water it was oriented to
the north and south magnetic poles.
When it reached the bottom and became
part Of the ooze 1t was no longer free to
move and became frozen in its position.
While this particular record is quite
difficult to read, 1t contains evidence Of
a shift in direction of nearly 100 degrees
in few hundred million years. This
may be intimately associated with the
profound changes in the climate Of the
Northern Hemisphere, of which evil
dence has been uncovered by geologists.
Remains of animal life thus far have
been very scant in the cores. AL the
fossils necessarily are very tiny.
In the shallow waters close to the
shore deposits washed down from the
land build up very quickly. During rela-
lively short periods of a few million
years they disturb the equilibrium Of
the earth's shell and are pushed up as
mountains. The process of mountain
building is violent one. Various layers
of sediment, rich in fossils of shallow
water creatures, are churned into an
almost inextricable confusion.
In the deep sea, beyond the range of
sediments from the land, conditions are
different. The bottom is built up very
slowly from the remains of sea animals,
dusts deposited on the ocean by the
winds, sands from melting icebergs, and
possibly minerals actually crystallized
out of sea water itself A foot of deep
sea deposits may represent time lapse
of 100000 years, whereas in shallow
waters within hundred miles of coast
such thickness might be built up In
1000 years, or less.
Once laid down, the deep sea deposits
never are disturbed. They are not sub
jected to the churning action Of noun
tain building. Temperatures and pres
sures remain constant through the ages.
1t now is generally agreed by geologists
that the great oceans have been in ap-
proximately their present positions since
the cooling of the earth about 100000
years ago. The deposits are laid down
on floor of hard, glasslike basalt, which
is the true shell of the earth. A COM
plete cross section through the sea floor
to this underlying basalt might consti-
tute a record, however sparse, Of the
history of the planet since the beginning
of time.
The longest Of the cores obtained by
DR.. Piggot measures 10 feet. It prob
ably contains q record of close to 5O,-
100000 years. Carnegie Institution ge-
ologists are working on q method by
which 1t may be possible to determine
the time lapse with some accuracy. It IL
thought the sea floor 10 rich in radium,
the amount Of which varies at different
depths; and the probability is that
greater part Of this radium has been
formed In the sea floor itself by the
breakdown Of uranium. If this turns
out to be true it will be possible since
the rate of radium formation is known,
to make fairly reliable calculations of
the age Of the deposits.
One problem in the study of DR.. Pig
got's cores is to determine the origin of
the so-cal1ed "red mud" which covers
the sea floor at the greatest depths. It
cannot be accounted for as the product
of slow sinking OF d-and-wave car
ried sediments, nor as the final debris
of dead animals. A close chemical study
is being made of it to determine if it
may not be distillation from sea water
itself.
The only method Of obtaining SAM
Piles Of the deep sea bottom in the past,
DR.. Piggot says, has been by means of a
primitive pincerlike instrument which
could take small bites out OF the ooze.
Study Of these has furnished the only
information available up to the present.
Would Declare War
IN Cernanv