Table 14. Major element composition of volcanic ash layers in Site 998 sediments.														
Notes: Shipboard XRF data given in weight percent. * = total iron reported as Fe2O3. Ma = age of layers in millions of years.														

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

Volcanic ash layers:														
165-998A-														
"13H-3, 25-27"	118	65.6	0.22	20.3	1.26	0.09	7.15	0.94	2.31	1.62	0.02	99.5	7.9	7.6
"13H-5, 118-120"	121	66.9	0.15	21.2	0.91	0.07	7.35	0.59	2.2	1.38		100.8	8.2	7.7
"14H-6, 16-18"	132	64	0.48	20.5	2.77	0.06	5.82	1.7	2.29	1.46	0.06	99.1	7.4	8.7
"16H-4, 106-109"	148	73.3	0.19	15	1.11	0.11	2.19	0.72	2.97	4.87	0.03	100.5	5.7	10.3
"19X-3, 54-57"	171	73	0.22	13.9	1.29	0.07	1.22	1.95	2.95	4.72	0.08	99.4	5.8	13.7
"20X-2, 9-11"	179	73.9	0.16	13	1.23	0.09	0.47	1.48	3.07	5.99	0.02	99.4	5.3	14.3
"20X-CC, 32-33"	183.5	75	0.11	13.1	1.44	0.04	0.38	1.46	2.79	6.05		100.4	5.4	14.4
"28X-4, 123-125"	259	74.7	0.09	12.9	1.33	0.06	0.25	1.84	3.23	5.97	0.01		4.9	19.4
"31X-3, 129-131"	286	70.5	0.2	15.2	2.01	0.05	1.62	2.11	3.48	4.75	0.05	99.9	5.9	21.2
"37X-1, 142-144"	341	59.8	0.22	16.8	3.19	0.01	4.09	9.27	2.59	1.68	0	97.7	13.3	24.4

165-998B-														
"1R-7, 51-53"	567	62.8	0.1	18.5	3.3	0.02	5.48	5.5	2.55	1.16	0.01	99.4	10.4	32.5
"15R-4, 30-32"	698	60.6	0.59	18	3.47	0.01	5.27	5.76	2.42	0.73	0.04		2.8	40.5

Ash turbidites:														
165-998B-														
"31R-CC, 5-7"	847.3	58.5	0.64	11.8	6.13	0.05	2.91	12.06	2.84	1.72	0.12		12.1	49.3
"32R-4, 37-40"	853	56.1	0.41	9.55	5.18	0.07	2.32	22.07	1.5	1.67	0.08		17.9	50.2
"35R-5, 109-111"	883	62.3	0.46	9.76	6.23	0.06	2.77	13.84	1.44	1.84	0.07		13.1	52
"35R-6, 68-71"	884	59	0.34	7.74	3.01	0.1	1.63	25.87	1.11	1.33	0.06			52