QUB-383a (Askja 1875 Tephra) at Borge

This search has found 17 analyses

The results of your search are shown on this page, which is divided into three sections. The first contains geochemical data in the form of electron probe microanalyses of the the tephra layer you have chosen, which can be downloaded. Most of these analyses will be of glass shards. The second section gives information about the instrument conditions and the third details about the sources of the data and the date and time of your search. You should always refer to the original sources to get the full context of the data presented here.

Geochemistry

To download this data as a tab delimited file click here:

	SiO₂	TiO₂	Al₂O₃	FeO	MgO	CaO	Na₂O	K₂O	Total	EP	Ref
Glass	75.45	0.17	12.17	2.33	0.44	1.09	3.09	2.80	97.55	17	1958
Glass	74.75	0.81	12.71	3.10	0.58	2.22	3.87	2.42	100.46	17	1958
Glass	74.01	0.79	12.60	3.50	0.67	2.43	3.36	2.30	99.65	17	1958
Glass	73.86	0.80	12.77	3.43	0.70	2.28	3.62	2.46	99.93	17	1958
Glass	73.48	0.81	12.47	2.93	0.56	2.07	3.78	2.55	98.63	17	1958
Glass	73.10	0.76	12.53	3.14	0.63	2.22	3.70	2.36	98.44	17	1958
Glass	72.97	0.80	12.68	3.35	0.65	2.44	3.80	2.27	98.97	17	1958
Glass	72.79	0.84	12.90	3.66	0.73	2.72	3.72	2.24	99.59	17	1958
Glass	72.78	0.88	12.74	3.41	0.64	2.62	3.77	2.45	100.29	17	1958
Glass	72.67	0.84	12.70	3.54	0.75	2.71	3.75	2.27	99.22	17	1958
Glass	72.40	0.82	12.58	3.36	0.69	2.42	3.99	2.34	98.59	17	1958
Glass	72.36	0.72	12.56	3.28	0.68	2.31	3.62	2.32	97.84	17	1958
Glass	72.11	0.86	12.72	3.84	0.81	2.74	3.70	2.29	99.06	17	1958
Glass	72.01	0.31	14.38	3.59	0.28	2.14	4.76	2.54	100.01	17	1958
Glass	71.92	0.97	12.93	3.84	0.79	2.84	3.77	2.39	99.44	17	1958
Glass	71.40	0.86	12.51	3.35	0.68	2.46	3.72	2.28	97.25	17	1958
Glass	69.94	0.90	13.22	4.26	0.89	3.15	3.48	2.14	97.97	17	1958
FeO: total iron is represented as FeO *original totals for normalised data (where applicable)

Instrument Conditions

These analyses were carried out under the following electron microprobe conditions.

Analysis Conditions (EP):	17
Instrument:	Jeol 733 Superprobe (Queens University, Belfast)
Beam Current:	10 nA
Acc. Volt:	15 kV
Sample:	Thin section mounted in araldite then ground and polished
Correction:	ZAF
Comments:	The beam was de-focused to a diameter of about 8 um. Sodium was analysed first with a short count time of 10 s. Count times for other elements varied from 15 to 40 s.

References

The data on this page is from the following source(s). If you use this data please acknowledge the source of the data. The number preceding each reference matches the Ref number on the data table above.

1958: Pilcher, J., Bradley, R. S., Francus, P. and Anderson, L. (2005) A Holocene tephra record from the Lofoten Islands, Arctic Norway. Boreas 34, 136-156.

Data Sources

All of the data contained in this database is either published or donated. When using the data, acknowledgement must be made of the original source of the data and that the data was obtained from Tephrabase. See Copyright information.

This Tephrabase search was made on 26/4/2024 at 14:13:24 local time, Edinburgh, Scotland, UK.