An Almahata Sitta EL3 fragment: implications for the complex thermal history of enstatite chondrites

Progress in Earth and Planetary Science

Table 2 Representative analyses of silicate phases (wt%)

Phase	Occurrence	SiO₂	TiO₂	Al₂O₃	Cr₂O₃	FeO	MnO	MgO	CaO	Na₂O	K₂O	Cl	Total	Fo/Wo/An	En/Ab	Fs/Or
Plagioclase	Chondrule	62.55	b.d	22.83	b.d	0.35	b.d	0.04	4.88	8.31	0.42	b.d	99.37	23.9	73.7	2.4
Glass	Chondrule	58.45	0.21	23.02	b.d	0.30	b.d	0.33	6.66	7.77	0.62	1.73	98.77
Glass	Chondrule	63.51	b.d	19.69	0.07	b.d	b.d	7.31	4.24	6.15	0.50	0.15	101.64
Olivine	Chondrule	42.63	b.d	b.d	b.d	0.06	0.15	56.60	b.d	b.d	b.d	b.d	99.44	99.9
Diopside	Chondrule	56.05	0.05	0.24	0.07	0.39	0.09	19.03	24.51	0.11	b.d	b.d	100.54	47.8	51.6	0.6
Diopside	Isolated mineral	55.63	b.d	0.24	b.d	0.35	b.d	19.18	24.59	0.15	b.d	b.d	100.15	47.7	51.8	0.5
Enstatite	Chondrule	58.91	b.d	0.30	b.d	b.d	b.d	39.22	0.49	0.06	b.d	b.d	98.98	0.9	99.1	0.0
Enstatite	Isolated mineral	60.03	b.d	0.05	b.d	0.33	b.d	39.34	0.47	b.d	b.d	b.d	100.22	0.8	98.7	0.5
Quartz	Chondrule	96.62	0.07	0.10	b.d	0.13	b.d	0.10	0.08	0.13	b.d	b.d	97.22

b.d.: below detection limits (3σ), 0.03 for SiO₂, Al₂O₃, MgO, and CaO, 0.04 for TiO₂, Na₂O, and K₂O, 0.05 for FeO, Cr₂O₃, and Cl, and 0.08 for MnO