<abstract xmlns="http://www.w3.org/1999/xhtml">The alpha effectiveness value (k-value) for the ESR (Electron Spin Resonance) signal due to SO3- in barite was revised by comparing the dose responses of the signal intensities to gamma rays and to 4 MeV He+ ion doses in natural sea-floor hydrothermal barite samples actually used for dating. Of the values obtained for a synthetic, a natural old, and a natural young samples, the one for the natural young sample is tentatively adopted, which is 0.053 ± 0.006, although further works are still necessary to establish this value.</abstract>

The alpha effectiveness value (k-value) for the ESR (Electron Spin Resonance) signal due to SO3- in barite was revised by comparing the dose responses of the signal intensities to gamma rays and to 4 MeV He+ ion doses in natural sea-floor hydrothermal barite samples actually used for dating. Of the values obtained for a synthetic, a natural old, and a natural young samples, the one for the natural young sample is tentatively adopted, which is 0.053 ± 0.006, although further works are still necessary to establish this value.

The alpha effectiveness of the dating ESR signal in barite: possible dependence with age

Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005,

Research Institute of Natural Sciences, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005,

Department of Earth and Planetary Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395,

Geochronometria

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The alpha effectiveness value (k-value) for the ESR (Electron Spin Resonance) signal due to SO3- in barite was revised by comparing the dose responses of the...

Sample No.	Site	Sampling Location		Depth (m)	Cruise No.	ESR age (year)	Efficiency to Heion dose(Gy^-1)	Efficiency togamma ray dose(Gy^-1)	k-value

		Latitude (N)	Longitude (E)
HPD#1621R07	Hatoma Knoll	24°51.33’	123°50.33’	1499	KY14-02	$1480_{- 160}^{+ 190}$ $1480_{ - 160}^{ + 190}$	0.020 ± 0.001	0.37 ± 0.04	0.053 ± 0.006

HPD#1358R03	Iheya North Knoll	27°47.46’	126°53.73’	982	NT12-06	$6300_{- 420}^{+ 500}$ $6300_{ - 420}^{ + 500}$	0.011 ± 0.001	0.11 ± 0.02	0.102 ± 0.022

Synthetic							0.022 ± 0.001	1.28 ± 0.07	0.017 ± 0.001

The alpha effectiveness of the dating ESR signal in barite: possible dependence with age

Publié en ligne: 30 déc. 2016

Pages: 174 - 178

Reçu: 14 févr. 2016

Accepté: 19 oct. 2016

DOI: https://doi.org/10.1515/geochr-2015-0043

Mots clés
barite, hydrothermal activities, ESR dating, alpha effectiveness

© 2015 T. Fujiwara.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The samples for the present study. The efficiency is the slope of the tangent at the point where signal intensity is zero on the saturating exponential curve of the dose response. The k -values are obtained as the ratio of the efficiencies to He ion implantation and to the gamma ray irradiation.

The alpha effectiveness of the dating ESR signal in barite: possible dependence with age

Publié en ligne: 30 déc. 2016

Pages: 174 - 178

Reçu: 14 févr. 2016

Accepté: 19 oct. 2016

DOI: https://doi.org/10.1515/geochr-2015-0043

Mots clésbarite, hydrothermal activities, ESR dating, alpha effectiveness

© 2015 T. Fujiwara.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The samples for the present study. The efficiency is the slope of the tangent at the point where signal intensity is zero on the saturating exponential curve of the dose response. The k -values are obtained as the ratio of the efficiencies to He ion implantation and to the gamma ray irradiation.

Mots clés
barite, hydrothermal activities, ESR dating, alpha effectiveness