scholarly journals Interior textures, chemical compositions, and noble gas signatures of Antarctic cosmic spherules: Possible sources of spherules with long exposure ages

2010 ◽  
Vol 45 (8) ◽  
pp. 1320-1339 ◽  
Author(s):  
Takahito OSAWA ◽  
Yukio YAMAMOTO ◽  
Takaaki NOGUCHI ◽  
Akari IOSE ◽  
Keisuke NAGAO
Keyword(s):  
Noble Gas ◽  
Chemical Compositions ◽  
Cosmic Spherules ◽  
Exposure Ages

scholarly journals A Petrologic and Noble Gas Isotopic Study of New Basaltic Eucrite Grove Mountains 13001 from Antarctica

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 279
Author(s):  
Chuantong Zhang ◽  
Bingkui Miao ◽  
Huaiyu He ◽  
Hongyi Chen ◽  
P. M. Ranjith ◽  
...  
Keyword(s):  
Noble Gas ◽  
Research Work ◽  
Cosmic Ray ◽  
Parent Body ◽  
Chemical Compositions ◽  
Isotopic Study ◽  
Impact Processes ◽  
Antarctic Research ◽  
Formation And Evolution ◽  
Grove Mountains

Howardite-Eucrite-Diogenite (HED) meteorite clan is a potential group of planetary materials which provides significant clues to understand the formation and evolution of the solar system. Grove Mountains (GRV) 13001 is a new member of HED meteorite, recovered from the Grove Mountains of Antarctica by the Chinese National Antarctic Research Expedition. This research work presents a comprehensive study of the petrology and mineralogy, chemical composition, noble gas isotopes, cosmic-ray exposure (CRE) age and nominal gas retention age for the meteorite GRV 13001. The output data indicate that GRV 13001 is a monomict basaltic eucrite with typical ophitic/subophitic texture, and it consists mainly of low-Ca pyroxene and plagioclase with normal eucritic chemical compositions. The noble gas based CRE age of the GRV 13001 is approximately 29.9 ± 3.0 Ma, which deviates from the major impact events or periods on the HED parent body. Additionally, the U,Th-4He and 40K-40Ar gas retention ages of this meteorite are ~2.5 to 4.0 Ga and ~3.6 to 4.1 Ga, respectively. Based on the noble gases isotopes and the corresponding ages, GRV 13001 may have experienced intense impact processes during brecciation, and weak thermal event after the ejection event at approximately 30 Ma.

scholarly journals Cosmic Ray Exposure Age Determinations of Cosmic Spherules from Marine Sediments

1985 ◽  
Vol 85 ◽  
pp. 179-181
Author(s):  
Kazuo Yamakoshi
Keyword(s):  
Mass Spectrometry ◽  
Cosmic Ray ◽  
High Energy ◽  
High Energy Accelerator ◽  
Exposure Age ◽  
Cosmic Spherules ◽  
Inner Region ◽  
Exposure Ages ◽  
Cosmic Ray Exposure Age ◽  
Cosmic Ray Exposure Ages

AbstractThe cosmic ray exposure ages of deep sea metalic lie spherules were determined by various methods; low level countings (Ni-59), neutron activation analysis (Mn-53), high energy accelerator mass spectrometry (Be-10, Al-26) and mass spectrometry (K isotopes). The exposure ages of 0.3 - 50 Ma were obtained. According to Poynting-Robertson effect, the starting points (supplying sources) are located at inner region of the orbit of Saturn.

scholarly journals Noble Gas Record of Japanese Chondrites

1989 ◽  
Vol 44 (10) ◽  
pp. 935-944
Author(s):  
Nobuo Takaoka ◽  
Masako Shima ◽  
Fumitaka Wakabayashi
Keyword(s):  
Noble Gas ◽  
Cosmic Ray ◽  
Ordinary Chondrites ◽  
Isotopic Signatures ◽  
Shock Heating ◽  
H Chondrites ◽  
Gas Loss ◽  
Exposure Ages ◽  
Cosmic Ray Exposure Ages ◽  
Gas Component

Abstract Concentrations and isotopic ratios of noble gases are reported for nineteen Japanese chondrites. Among those, Nio (H3-4) is a solar-gas-rich meteorite.U/Th - He ages are younger than K - Ar ages for all meteorites studied. Six of the nine L-chondrites give significantly young K-Ar ages, suggesting gas loss by impact shock heating. The remaining three L-chondrites and seven of the ten H-chondrites have K-Ar ages older than 4 Ga. The L-chondrite Nogata and the H-chondrites Numakai, Ogi and Higashi-Koen have concordant ages.Cosmic-ray exposure ages for six of the H-chondrites show clustering around the 6-Myr peak in the distribution of exposure ages, while those for the L-chondrites, ranging from 8.2 to 64 Myr, do not show clustering.Fukutomi (L4) contains trapped 36Ar in excess, 3.5 times enriched compared to the highest value so far reported for type-4 ordinary chondrites except solar-gas-rich chondrites. The 36Ar/132Xe and 84Kr/132Xe ratios fit along a mixing line between a planetary and a sub-solar (or argon-rich) component found in separates of E-chondrites [43], The Xe isotopic composition is identical with that in Abee and Kenna. The isotopic signatures suggest that this meteorite may contain mineral fragments bearing the noble gas component found in E-chondrites or ureilites. Fukutomi also contains 80Kr, 82Kr and 128Xe produced by epithermal neutron captures on 79Kr, 81Kr and 127I, respectively. From the neutron-produced Kr, the preatmospheric minimum radius is estimated to be 20 cm with an assumption of a spherical meteoroid.

Oxygen isotopic and chemical compositions of cosmic spherules collected from the Antarctic ice sheet: Implications for their precursor materials

2005 ◽  
Vol 69 (24) ◽  
pp. 5789-5804 ◽  
Author(s):  
Toru Yada ◽  
Tomoki Nakamura ◽  
Takaaki Noguchi ◽  
Noriko Matsumoto ◽  
Minoru Kusakabe ◽  
...  
Keyword(s):  
Ice Sheet ◽  
Chemical Compositions ◽  
Antarctic Ice Sheet ◽  
Cosmic Spherules ◽  
Oxygen Isotopic ◽  
The Antarctic

scholarly journals Analytical protocols for Phobos regolith samples returned by the Martian Moons eXploration (MMX) mission

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Wataru Fujiya ◽  
Yoshihiro Furukawa ◽  
Haruna Sugahara ◽  
Mizuho Koike ◽  
Ken-ichi Bajo ◽  
...  
Keyword(s):  
Noble Gas ◽  
Geochemical Data ◽  
Chemical Compositions ◽  
Isotopic Compositions ◽  
Bulk Chemical ◽  
Sample Return Mission ◽  
Crucial Information ◽  
Sampling Systems ◽  
Japan Aerospace Exploration Agency ◽  
Analytical Protocols

AbstractJapan Aerospace Exploration Agency (JAXA) will launch a spacecraft in 2024 for a sample return mission from Phobos (Martian Moons eXploration: MMX). Touchdown operations are planned to be performed twice at different landing sites on the Phobos surface to collect > 10 g of the Phobos surface materials with coring and pneumatic sampling systems on board. The Sample Analysis Working Team (SAWT) of MMX is now designing analytical protocols of the returned Phobos samples to shed light on the origin of the Martian moons as well as the evolution of the Mars–moon system. Observations of petrology and mineralogy, and measurements of bulk chemical compositions and stable isotopic ratios of, e.g., O, Cr, Ti, and Zn can provide crucial information about the origin of Phobos. If Phobos is a captured asteroid composed of primitive chondritic materials, as inferred from its reflectance spectra, geochemical data including the nature of organic matter as well as bulk H and N isotopic compositions characterize the volatile materials in the samples and constrain the type of the captured asteroid. Cosmogenic and solar wind components, most pronounced in noble gas isotopic compositions, can reveal surface processes on Phobos. Long- and short-lived radionuclide chronometry such as 53Mn–53Cr and 87Rb–87Sr systematics can date pivotal events like impacts, thermal metamorphism, and aqueous alteration on Phobos. It should be noted that the Phobos regolith is expected to contain a small amount of materials delivered from Mars, which may be physically and chemically different from any Martian meteorites in our collection and thus are particularly precious. The analysis plan will be designed to detect such Martian materials, if any, from the returned samples dominated by the endogenous Phobos materials in curation procedures at JAXA before they are processed for further analyses.

Über den Helium- und Neongehalt von Steinmeteoriten und deren radiogene und kosmogene Alter

1962 ◽  
Vol 17 (12) ◽  
pp. 1092-1102 ◽  
Author(s):  
H. Hintenberger ◽  
H. König ◽  
H. Wanke
Keyword(s):  
Neutron Activation ◽  
Isotopic Composition ◽  
Total Content ◽  
Cosmic Ray ◽  
Decay Rates ◽  
Chemical Compositions ◽  
Diffusion Loss ◽  
Helium 3 ◽  
Exposure Ages ◽  
Cosmic Ray Exposure Ages

The total content as well as the isotopic composition of helium and neon of 19 chondrites and 5 achondrites have been determined. A description of the analytical method is given. Large variations of the ratios 3He/21Ne were observed and it is shown that these variations cannot be explained by differences in the chemical compositions of the meteorites only.Radiogenic helium ages and cosmic ray exposure ages have been calculated. The calculation of the helium ages was mainly based on uranium determinations by means of the xenon-method previously developed in this laboratory. The radiogenic helium ages range from 0.42 · 109 to 4.5 · 109 years. The values obtained for the helium ages are compared with the figures for the potassium-argon ages formerly derived by a neutron activation method newly developed and of those stated in the literature. It turns out that in most cases the radiogenic helium ages are lower, sometimes considerably lower than the potassium-argon ages indicating diffusion loss of helium and certainly in smaller quantities also of argon.Using tritium and sodium 22 decay rates from the literature for the calculations of the production rates for helium 3 and neon 22 cosmic ray exposure ages for all the meteorites analysed were obtained. These exposure ages vary between 0.3 ·106 and 29·106 years. No correlation between radiogenic ages and cosmic ray exposure ages and no grouping of the exposure ages have been found.

scholarly journals Analytical Protocols for Phobos Regolith Samples Returned by the Martian Moons Exploration (MMX) Mission

2020 ◽  
Author(s):  
Wataru Fujiya ◽  
Yoshihiro Furukawa ◽  
Haruna Sugahara ◽  
Mizuho Koike ◽  
Ken-ichi Bajo ◽  
...  
Keyword(s):  
Noble Gas ◽  
Building Blocks ◽  
Chemical Compositions ◽  
Isotopic Compositions ◽  
Bulk Chemical ◽  
Sample Return Mission ◽  
Crucial Information ◽  
Sampling Systems ◽  
Japan Aerospace Exploration Agency ◽  
Analytical Protocols

Abstract Japan Aerospace Exploration Agency (JAXA) will launch a spacecraft in 2024 for a sample return mission from Phobos (Martian Moons eXploration: MMX). Touchdown operations are planned to be performed twice at different landing sites on the Phobos surface to collect >10 g of the Phobos surface materials with coring and pneumatic sampling systems on board. The Sample Analysis Working Team (SAWT) of MMX is now designing analytical protocols of the returned Phobos samples to shed light on the origin of the Martian moons as well as the evolution of the Mars-moon system. Observations of petrology and mineralogy, and measurements of bulk chemical compositions and stable isotopic ratios of, e.g., O, Cr, and Ti can provide crucial information about the origin of Phobos. If Phobos is a captured asteroid composed of primitive chondritic materials, as inferred from its reflectance spectra, the nature of organic matter as well as bulk H, N, and Zn isotopic compositions characterize the volatile materials in the samples and constrain the type of the captured asteroid. Cosmogenic and solar wind components, most pronounced in noble gas isotopic compositions, can reveal surface processes on Phobos. Long- and short-lived radionuclide chronometry such as 53Mn-53Cr and 87Rb-87Sr systematics can date pivotal events like impacts, thermal metamorphism, and aqueous alteration on Phobos. It should be noted that the Phobos regolith is expected to contain a small amount of materials delivered from Mars, which may be physically and chemically different from any Martian meteorites in our collection and thus are particularly precious. The analysis plan will be designed to detect such Martian materials, if any, from the returned samples dominated by the Phobos building blocks in curation procedures at JAXA before they are processed for further analyses.

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