Table 11. Major oxide composition of volcanic ash layers.
Notes: Shipboard XRF data in weight percent. Total iron reported as Fe2O3. LOI = loss on ignition.

Core, section, interval (cm)	Depth (mbsf)	SiO2	TiO2	Al2O3	Fe2O3	MnO	MgO	CaO	Na2O	K2O	P2O5	Total	LOI

165-1000A-
22H-2, 57-60	195	70.7	0.33	16.0	3.50	0.06	1.94	0.95	3.33	3.79	0.04	100.6	6.85
56X-CC, 18-21	523	73.2	0.20	14.4	2.51	0.04	1.05	1.26	3.11	4.36	0.03	100.2	6.14
58X-2, 47-50	536	62.6	0.44	19.7	6.13	0.01	3.77	3.21	2.83	1.10	0.05	99.8	6.62

165-1000B-
6R-4, 143-145	537	65.8	0.56	17.9	4.40	0.04	3.27	2.72	3.17	1.60	0.06	99.5	7.26
11R-1, 142-145	582	66.2	0.36	18.0	4.43	0.02	3.80	1.50	3.06	1.95	0.05	99.4	7.06
19R-2, 88-91	660	66.3	0.20	17.9	4.39	0.02	4.96	0.94	3.25	2.12	0.04	100.1	7.02
21R-4, 43-46	681												9.36