Preliminary investigation of the 20 August 2014 debris flows triggered by a severe rainstorm in Hiroshima City, Japan

Geoenvironmental Disasters

Table 2 Major element compositions of granite and related samples in the Midori-ga-oka gully

Location	Type	SiO₂	TiO₂	Al₂O₃	Fe₂O₃	MnO	MgO	CaO	Na₂O	K₂O	P₂O₅	LOI	Total	CIA
G1	FG	72.58	0.23	14.97	2.45	0.05	0.50	1.75	3.10	4.10	0.03	0.71	100.47	54.2
G1	GS	71.74	0.31	14.74	3.24	0.08	0.62	1.66	2.79	3.52	0.01	1.96	100.66	56.4
G2	FG	74.59	0.19	13.80	2.21	0.05	0.43	1.18	2.92	4.26	0.02	0.80	100.45	54.5
G2	GS	69.46	0.29	16.43	2.89	0.16	0.54	0.67	1.88	3.71	0.04	5.20	101.27	66.6
G2	GS	67.20	0.38	17.87	3.38	0.19	0.66	0.45	1.71	3.87	0.05	6.09	101.85	69.9
G3	FG	73.69	0.25	13.80	2.87	0.06	0.57	1.64	2.91	3.98	0.04	0.52	100.33	53.5
G3	WG	72.45	0.26	14.55	2.68	0.08	0.56	1.56	2.85	3.84	0.02	1.79	100.65	55.5
G3	GS	72.78	0.26	14.56	2.59	0.13	0.51	1.01	2.43	3.80	0.00	2.75	100.81	59.4
G4	FG	76.52	0.11	12.85	1.65	0.04	0.31	1.08	2.92	4.50	0.01	0.19	100.17	52.6
G4	WG	76.39	0.12	12.87	1.64	0.04	0.32	1.04	2.89	4.37	0.01	0.44	100.14	53.1
G4	GS	72.72	0.23	14.55	2.38	0.08	0.45	0.79	2.25	3.86	0.02	3.44	100.78	61.1

G1 to G4: sample locations, showing in Fig. 5. FG Fresh granite, WG Weathered granite, GS Granitic soil, LOI loss on ignition, CIA Chemical Index of Alteration (Nesbitt and Young, 1982)