basin and poorly drained, the color of the Nm-NK is orange-gray, the range of
Al o + Fe o /2 values is 4.8–6.6 g kg
À1
, and the major clay mineral is halloysite.
Changes in weathering of volcanic glass with drainage conditions were also
observed by Stoops (2007).
References
Aramaki S (1984) Formation of the Aira Caldera, southern Kyushu, À22,000 years ago. J Geophys
Res 89:8485–8501
Arnalds O, Bartoli F, Buurman P, Oskarsson H, Stoops G, Garcia-Rodeja E (2007) Soils of volcanic
regions in Europe. Springer, Berlin Heiderberg
Baer EM, Fisher RV, Fuller M, Valentine G (1997) Turbulent transport and deposition of the Ito
pyroclastic flow: determination using anisotropy of magnetic susueptivility. J Geophys Res
102:22565–22586
Brimhall GH, Chadwick OA, Lewis CJ, Compston W, Williams IS, Danti KJ, Dietrich WE, Power
ME, Hendricks D, Bratt J (1991) Deformational mass transport and invasive processes in soil
evolution. Science 255:695–702
Jotohara
Urushihara
Sobanome
Yukawa Amanuma
Distance
from
Jotohara
Numazawa
lake
Ht.
Ht.
Allo. Im.
with Ht.
Fukushima
Prefecture
Nm-NK
(4.6ka)
Altitude (m a.s.l.)
Aizu basin
Urushihara
Yukawa
a
c
e
b
d
Fig. 4.31 Major weathering products, and examples of soil profile including Nm-NK tephra in
Aizu, Japan. Jotohara is the nearest study site to Numazawa caldera lake (a, b: good drainage, c, d,
e: restricted drainage). The shaded position of (a) to (e) shows Nm-NK tephra at each site, and major
weathering products “Allo.”, “Im.” and “Ht.” denote allophane, imogolite, and halloysite,
respectively
92
4 Non-crystalline Inorganic Constituents of Soil