Table 1 Major elemental compositions of the deeply weathered rocks transitioning into the red soil and their host rocks.

From: Kibi Plateau: A stable-coherent tectonic unit in the active Japanese Islands

SiteRS1RS2RS3RS4RS5
(wt%)Red soilRed soilHost rockRed soilHost rockRed soilRed soilHost rock
SiO254.2065.9575.0266.9271.2779.2261.0871.78
TiO21.510.700.100.440.270.500.910.24
Al2O329.0325.1613.1923.0914.4414.5625.4013.58
ΣFe2O312.416.572.055.133.403.598.674.17
MnO0.040.010.050.020.060.020.160.09
MgO0.760.300.200.380.490.280.720.42
CaO0.000.001.100.002.270.000.001.89
Na2O0.190.203.550.323.960.190.213.84
K2O1.070.484.263.263.630.612.183.55
P2O50.090.010.010.020.070.010.040.07
Total99.3099.3899.5399.5899.8698.9899.3799.63
LOI14.8512.490.638.260.246.3013.020.66
Host rock typeSchistose rockRhyoliteGranitePeliteGranite
AgePermianCretaceousCretaceousPermianCretaceous
LatitudeN34°53'38.7"N34°55'54.6"N34°52'15.2"N34°52'19.1"N34°52'48.1"N34°47'24.3"
LongitudeE134°02'34.8"E134°00'47.6"E134°01'26.6"E134°01'26.0"E133°56'44.0"E133°51'54.6"
Elevation360 m422 m250 m240 m288 m308 m
  1. The sampling sites of RS1 to RS4 are shown in Fig. 3a and the site (Fig. 2a) of RS5 is shown in Fig. 1a. This table also shows the host rock types and their ages, and the latitude, longitude and elevation of the sampling sites.