Presentation on theme: "Thermoluminescence and ESR study of shocked minerals K. Noritake, K. Ninagawa, T. Usami, S. Toyoda (Okayama University of Science)"— Presentation transcript:
Thermoluminescence and ESR study of shocked minerals K. Noritake, K. Ninagawa, T. Usami, S. Toyoda (Okayama University of Science)
Objective We investigated the change by the shock metamorphism in the lattice defects in quartz, albite and oligoclase by thermoluminescence (TL) and electron spin resonance (ESR).
I Sample II Instrument 1. Two stage light-gas gun 2. Gamma-ray irradiation 3. TL spectra 4. ESR III Result 1. Quartz 2. Albite (2-1 Minas, 2-2 Siga, 2-3 Niigata) 3. Oligoclase IV Application to Ries crater
Quartz Minas Geras, Brazil Oligoclase Aichi Japan sample We used a quartz from Minas Brazil, three albite from Minas Brazil, Niigata Japan and Siga Japan, and a oligoclace from Aichi Japan as samples. I Sample
II Instrument 1. Two stage light-gas gun JAXA (Japan Aerospace Exploration Agency ） gun powder piston compression cylinder He gas projectile shot cylinder Velocity measure sample holder sample shock a magnify figure
Sample holder Sample holder made of brass. height 5mmФ6mm Polycarbonate projectile Silver Screw bolt Copper fastener sample or powder sample 5mm 6mm φ 20mm 10cm solid sample Sample holder shock Picture is SUS holder.
Shock experiments Sample typeSample sourceProjectile velocity （ km/s ） QuartzMinas Geras, Brazil 2.85 AlbiteMinas Geras, Brazil 4.15 Niigata, Japan 4.21 Siga, Japan 4.18 OligoclaseAichi, Japan 3.50
2. gamma-ray irradiation Kyoto University Research Reactor Institute (KURRI) 60 Co gamma-ray Dose 10KGy Kumatoricho, Izuminangun, Osaka,Japan
3. TL spectra MONTOR TV distributor video camera Photon counting board PC ADC RAM USB HDD PAL 256 240 Memory 1Memory 2 memory3 Memory 4
4. ESR (electron spin resonance) JEOL X-band ESR spectrometer ・ JES-PX2300 ・ room temperature Condition ・ microwave intensity 1mW ・ modulation amplitude 100kHz, ・ sweeping 10mT/30sec ・ time constant 0.03sec in Okayama Univ. of Science
Thermolminescence spectra of Quartz (Minas Gerais, Brazil) shocked, 2.85km/s 10kGy unshocked 10kGy TLglow curve spectra III Result 1. Quartz spectra TLglow curve
For all of the three albites, TL spectra increase around 500nm 300 ℃, and the new ESR signal (g=2.0031 unknown) produced by the shock.
Results The changes in lattice defects in the minerals by shock Metamorphism. I think that I can apply this result to minerals in Crater. It is thought that it is possible to use it also to discover Crater.
Ries crater ESR spectra ： 10kGy 25~35GPa 35~40GPa unknow E1’ center Ge center
X-ray 装置 X 線と γ 線は発生機構が違う X 線は原子核外、 γ 線は原子核内で発生する X 線と γ 線は物理的性質を同じくするもの 20 号館２階 X 線照射室 24V 電源 30KeV 高圧電源 最大出力 50KeV 1mA X-ray 装置 線源
Experimental procedure 1.Shock experiments were carried out by two stage light gas gun in JAXA. 2. 10kGy gamma rays irradiation was carried out by 60 Co in KURRI. 3. Their thermoluminescence (TL) spectra were measured by TL readout system in Okayama Univ. of Science. 4. ESR spectra were measured by JEOL X-band ESR spectrometer in Okayama Univ. of Science.
Shock experiments Experimental day Sample typeSample sourceProjectile velocity （ km/s ） 2 nd Aug. 2007AlbiteMinas Geras, Brazil 4.15 Niigata, Japan 4.21 Siga, Japan 4.18 25 th Dec. 2007QuartzMinas Geras, Brazil 2.85 OligoclaseAichi, Japan 3.50