Michihiro
KAWANO
Review of the
Studies concerning Physical Speleology in Japan |
In Japan, the reports on caves appeared for the
first time in
scientific magazines before and after 1890. Those on lava caves were
made in
1883, and on limestone caves in 1903. But many people have paid
increased
attention to caves since some caves were designated to the natural
monuments in
the 1920's. The surveys and studies of caves in that time were
descriptive
investigations regarding the morphology of caves and the speleothems.
In the
1950's, caves aroused the interest of geologists because vertebrate
fossils
were discovered in the cave deposits. Before and after 1970, several
papers
concerning the development of caves were published. These papars dealt
with the
relation between the vertical distribution of caves and the age of cave
development. In the midst of the 1970's, it was recognized by the
minute
observation of corrosional feature of caves that many caves had
developed from
the phreatic tube. The Speleological Society of Japan was organized in
1975,
when cave researching was becoming active. During the present decade,
the
speleological investigations have developed rapidly. The lectures at
the annual
meeting and the papers in the journal of the Speleological Society of
Japan
deal with various subjects in geological branches as follows.
a.
Studies of the morphology, origin and
development of limestone caves. Since 1975, several caves have been
surveyed
and investigated in detail, and the origin and development of these
caves have
been clarified. These caves have different and characteristic
histories;
accordingly the origin and development can not be explained on one
specific
theory. And also, the systematic studies of cave development, karst
topography
and ground water system have been pursued gradually.
b.
Studies of speleothems and cave
minerals. The researchers of speleothems and cave minerals are very
few, but
during the decade from 1975, new localities of cave minerals have been
found
almost every year. The theoretical investigations of speleothems have
also been
carried out.
c.
Studies of karst hydrology and
geochemical research of cave water. These researches were carried out
on
several caves, especially, caves in Akiyoshi karst region. The
corroborative
studies of ground water in this region were pursued by the tracer of
chemicals,
and the ground water system was clarified. By the way, on the chemical
analysis
of cave and spring water, it was clarified that the ground water system
is
divided by chemical composition of water, and where the origin of
ground water
is begun to be made clear.
d.
Other studies. The most interesting
studies are conducted by the ESR dating method. This method
was
first established by the dating of
stalactites in Akiyoshi-do Cave in 1975. Then, this method has been
available
for geology, archaeology, anthropology etc. The ESR dating method is
expected
to be an important method of cave chronology.
|
Yoshikazu
HASEGAWA
Japanese Cave and
Fissure Deposits and Paleontology |
Occurrence
of abundant animal
fossils in the deposits of caves and fissures was known for long, and
those
fossils have been treated with scientific interest. Among the published
records
of such fossils, the work of W. BUCKLAND (1823), a British
paleontologist, is
notable. In Japan, fossils in fissure deposits were reported first from
the
Kuzuu Formation (SHIKAMA, T., 1933, 1937, 1949). Since then, a number
of fossil
occurrences have been recorded in Yamaguchi, Shizuoka, Aomori and
Okinawa
Prefectures etc. Most of the fossils in cave or fissure deposits are
vertebrates, of which mammals are studied fairly well while the
knowledge of
other taxa such as reptiles and birds is still insufficient. Geologic
age of
the deposits, as inferred from the fossils, ranges from Middle to Late
Pleistocene, and little is known about older deposits of this kind. It
is
supposed, accordingly, that the cave and fissure deposits in Japan were
accumulated mostly during the Middle-Late Pleistocene period. As for
the fossil
mammals, nearly one half of the species must have becolne extinct by
the Late
Pleistocene time (HASEGAWA, Y., 1977). |
Naruhiko
KASHIMA
A Short Review of
Caving Techniques |
About
sixty years ago the late
councilor of the Speleological Society of Japan, Hiroshi YAMAUCHI,
began a cave
exploration in Japan by his unaided efforts. During this period, he
pioneered
the creative caving techniques and equipments, for example, cave
measurement
materials and methods, wire ladder and travelling lifeline system,
making the
exploration possible for Japanese cavers and still retaining today;
this should
never be forgotten. Every member of the Speleological Society of Japan,
irrespective of specialty, must hold a competent skill of caving
techniques.
Recently, there are three important topics of caving techniques
concerning
single rope techniques, cave diving and cave rescue. These topics are
discussed
side by side in some technical publications and international
organizations. I
hope the members of caving techniques section will be to tackle these
technical
problems and will be to throw a new light in this field, over the next
ten
years. |