E01-JEM ARM 200CF
E02-JEM ARM 300CF
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Takaaki
Noguchi
,
Toru
Matsumoto
,
Akira
Miyake
,
Yohei
Igami
,
Mitsutaka
Haruta
,
Hikaru
Saito
,
Satoshi
Hata
,
Yusuke
Seto
,
Masaaki
Miyahara
,
Naotaka
Tomioka
,
Hope A.
Ishii
,
John P.
Bradley
,
Kenta K.
Ohtaki
,
Elena
Dobrică
,
Hugues
Leroux
,
Corentin Le
Guillou
,
Damien
Jacob
,
Francisco
De La Peña
,
Sylvain
Laforet
,
Bahae-Eddine
Mouloud
,
Maya
Marinova
,
Falko
Langenhorst
,
Dennis
Harries
,
Pierre
Beck
,
Thi H. V.
Phan
,
Rolando
Rebois
,
Neyda M.
Abreu
,
Jennifer
Gray
,
Thomas
Zega
,
Pierre-M.
Zanetta
,
Michelle S.
Thompson
,
Rhonda
Stroud
,
Kate
Burgess
,
Brittany A.
Cymes
,
John C.
Bridges
,
Leon
Hicks
,
Martin R.
Lee
,
Luke
Daly
,
Phil A.
Bland
,
William A.
Smith
,
Sam
Mcfadzean
,
Pierre-Etienne
Martin
,
Paul A. J.
Bagot
,
Dennis
Fougerouse
,
David W.
Saxey
,
Steven
Reddy
,
William D. A.
Rickard
,
Michael E.
Zolensky
,
David R.
Frank
,
James
Martinez
,
Akira
Tsuchiyama
,
Masahiro
Yasutake
,
Junya
Matsuno
,
Shota
Okumura
,
Itaru
Mitsukawa
,
Kentaro
Uesugi
,
Masayuki
Uesugi
,
Akihisa
Takeuchi
,
Mingqi
Sun
,
Satomi
Enju
,
Aki
Takigawa
,
Tatsuhiro
Michikami
,
Tomoki
Nakamura
,
Megumi
Matsumoto
,
Yusuke
Nakauchi
,
Masanao
Abe
,
Satoru
Nakazawa
,
Tatsuaki
Okada
,
Takanao
Saiki
,
Satoshi
Tanaka
,
Fuyuto
Terui
,
Makoto
Yoshikawa
,
Akiko
Miyazaki
,
Aiko
Nakato
,
Masahiro
Nishimura
,
Tomohiro
Usui
,
Toru
Yada
,
Hisayoshi
Yurimoto
,
Kazuhide
Nagashima
,
Noriyuki
Kawasaki
,
Naoya
Sakamotoa
,
Peter
Hoppe
,
Ryuji
Okazaki
,
Hikaru
Yabuta
,
Hiroshi
Naraoka
,
Kanako
Sakamoto
,
Shogo
Tachibana
,
Sei‐ichiro
Watanabe
,
Yuichi
Tsuda
Diamond Proposal Number(s):
[31953, 30752]
Abstract: Samples returned from the carbonaceous asteroid (162173) Ryugu by the Hayabusa2 mission revealed that Ryugu is composed of materials consistent with CI chondrites and some types of space weathering. We report detailed mineralogy of the fine-grained Ryugu samples allocated to our “Sand” team and report additional space weathering features found on the grains. The dominant mineralogy is composed of a fine-grained mixture of Mg-rich saponite and serpentine, magnetite, pyrrhotite, pentlandite, dolomite, and Fe-bearing magnesite. These grains have mineralogy comparable to that of CI chondrites, showing severe aqueous alteration but lacking ferrihydrite and sulfate. These results are similar to previous works on large Ryugu grains. In addition to the major minerals, we also find many minerals that are rare or have not been reported among CI chondrites. Accessory minerals identified are hydroxyapatite, Mg-Na phosphate, olivine, low-Ca pyroxene, Mg-Al spinel, chromite, manganochromite, eskolaite, ilmenite, cubanite, polydymite, transjordanite, schreibersite, calcite, moissanite, and poorly crystalline phyllosilicate. We also show scanning transmission electron microscope and scanning electron microscope compositional maps and images of some space-weathered grains and severely heated and melted grains. Although our mineralogical results are consistent with that of millimeter-sized grains, the fine-grained fraction is best suited to investigate impact-induced space weathering.
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Nov 2023
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E01-JEM ARM 200CF
E02-JEM ARM 300CF
I14-Hard X-ray Nanoprobe
I18-Microfocus Spectroscopy
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Open Access
Abstract: Phyllosilicate minerals in the carbonaceous chondrites provide insights into processes in primitive parent bodies of the early Solar System. It is widely agreed that the CM- and CI-type carbonaceous chondrites underwent aqueous alteration on their parent bodies, resulting in phyllosilicate-rich matrices, where the dominant mineral phase is serpentine. There are many previous studies investigating phyllosilicate structure in carbonaceous chondrites, however, the presence of sulfur in these minerals and its effect on crystal lattice structure has not been studied in detail. We are investigating how the presence of sulfur (up to ≃9-10 wt% SO3) in serpentine phyllosilicate regions effects basal lattice spacing measurements of serpentine-like minerals in CM- and CI-type chondritic and related asteroidal material.
Four specimens are being studied for this work: Winchcombe and Aguas Zarcas (CM-type), and Ryugu samples (A0058-C2001-08, A0104-00200502 and A0104-01700602) from Hayabusa2 and Ivuna (CI-type). All samples are TEM wafers. We have used a multi-technique approach to study the samples, with the E01 JEOL ARM200CF and E02 JEOL ARM300CF electron microscopes at the ePSIC facility at Diamond Light Source in Harwell, UK. EDS compositional data has been collected using the E01 microscope, whilst HRTEM and HAADF imaging data has been collected at E02. At E02 we are also applying a new 4D-STEM nano-diffraction technique in order to collect lattice spacing data to correlate with our other HRTEM results. Fe-K XANES analyses on Winchcombe and Ryugu have been carried out using the I18 microprobe and I14 hard x-ray nanoprobe respectively, also at Diamond Light Source, to constrain Fe3+/ΣFe. By combining these techniques we aim to better understand the physical and chemical structure of serpentine-like minerals in carbonaceous chondrites.
Initial analyses have shown that sulfur presence in carbonaceous chondrite phyllosilicates reduces the basal lattice spacings of serpentine-like minerals. In these sulfur-bearing regions, we have been finding lattice spacings in the range ~0.60-0.74nm for the CM-type chondrites. For the CI-type, these range between ~0.65-0.76nm. Differences in the reduced lattice spacing ranges are likely related to the redox state of the sulfur. In Ryugu and other carbonaceous chondrites the sulfur appears reduced; its content in serpentine is low and we see FeS grains. Comparatively, in Winchcombe (and others) more of the sulfur seems to be in the serpentine structure.
We can conclude that in serpentine-like minerals, the presence of sulfur appears to reduce basal lattice spacing values compared to the expected d-spacing value of 0.70nm for serpentine. Possible reasons for this include further investigations into the valency of the sulfur ions, the bonding environment within serpentine layers, and the location of sulfur in either the octa- or tetrahedral lattice sites.
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Feb 2023
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I14-Hard X-ray Nanoprobe
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Takaaki
Noguchi
,
Toru
Matsumoto
,
Akira
Miyake
,
Yohei
Igami
,
Mitsutaka
Haruta
,
Hikaru
Saito
,
Satoshi
Hata
,
Yusuke
Seto
,
Masaaki
Miyahara
,
Naotaka
Tomioka
,
Hope A.
Ishii
,
John P.
Bradley
,
Kenta K.
Ohtaki
,
Elena
Dobrică
,
Hugues
Leroux
,
Corentin
Le Guillou
,
Damien
Jacob
,
Francisco
De La Peña
,
Sylvain
Laforet
,
Maya
Marinova
,
Falko
Langenhorst
,
Dennis
Harries
,
Pierre
Beck
,
Thi H. V.
Phan
,
Rolando
Rebois
,
Neyda M.
Abreu
,
Jennifer
Gray
,
Thomas
Zega
,
Pierre-M.
Zanetta
,
Michelle S.
Thompson
,
Rhonda
Stroud
,
Kate
Burgess
,
Brittany A.
Cymes
,
John C.
Bridges
,
Leon
Hicks
,
Martin R.
Lee
,
Luke
Daly
,
Phil A.
Bland
,
Michael E.
Zolensky
,
David R.
Frank
,
James
Martinez
,
Akira
Tsuchiyama
,
Masahiro
Yasutake
,
Junya
Matsuno
,
Shota
Okumura
,
Itaru
Mitsukawa
,
Kentaro
Uesugi
,
Masayuki
Uesugi
,
Akihisa
Takeuchi
,
Mingqi
Sun
,
Satomi
Enju
,
Aki
Takigawa
,
Tatsuhiro
Michikami
,
Tomoki
Nakamura
,
Megumi
Matsumoto
,
Yusuke
Nakauchi
,
Masanao
Abe
,
Masahiko
Arakawa
,
Atsushi
Fujii
,
Masahiko
Hayakawa
,
Naru
Hirata
,
Naoyuki
Hirata
,
Rie
Honda
,
Chikatoshi
Honda
,
Satoshi
Hosoda
,
Yu-Ichi
Iijima
,
Hitoshi
Ikeda
,
Masateru
Ishiguro
,
Yoshiaki
Ishihara
,
Takahiro
Iwata
,
Kousuke
Kawahara
,
Shota
Kikuchi
,
Kohei
Kitazato
,
Koji
Matsumoto
,
Moe
Matsuoka
,
Yuya
Mimasu
,
Akira
Miura
,
Tomokatsu
Morota
,
Satoru
Nakazawa
,
Noriyuki
Namiki
,
Hirotomo
Noda
,
Rina
Noguchi
,
Naoko
Ogawa
,
Kazunori
Ogawa
,
Tatsuaki
Okada
,
Chisato
Okamoto
,
Go
Ono
,
Masanobu
Ozaki
,
Takanao
Saiki
,
Naoya
Sakatani
,
Hirotaka
Sawada
,
Hiroki
Senshu
,
Yuri
Shimaki
,
Kei
Shirai
,
Seiji
Sugita
,
Yuto
Takei
,
Hiroshi
Takeuchi
,
Satoshi
Tanaka
,
Eri
Tatsumi
,
Fuyuto
Terui
,
Ryudo
Tsukizaki
,
Koji
Wada
,
Manabu
Yamada
,
Tetsuya
Yamada
,
Yukio
Yamamoto
,
Hajime
Yano
,
Yasuhiro
Yokota
,
Keisuke
Yoshihara
,
Makoto
Yoshikawa
,
Kent
Yoshikawa
,
Ryohta
Fukai
,
Shizuho
Furuya
,
Kentaro
Hatakeda
,
Tasuku
Hayashi
,
Yuya
Hitomi
,
Kazuya
Kumagai
,
Akiko
Miyazaki
,
Aiko
Nakato
,
Masahiro
Nishimura
,
Hiromichi
Soejima
,
Ayako I.
Suzuki
,
Tomohiro
Usui
,
Toru
Yada
,
Daiki
Yamamoto
,
Kasumi
Yogata
,
Miwa
Yoshitake
,
Harold C.
Connolly
,
Dante S.
Lauretta
,
Hisayoshi
Yurimoto
,
Kazuhide
Nagashima
,
Noriyuki
Kawasaki
,
Naoya
Sakamoto
,
Ryuji
Okazaki
,
Hikaru
Yabuta
,
Hiroshi
Naraoka
,
Kanako
Sakamoto
,
Shogo
Tachibana
,
Sei-Ichiro
Watanabe
,
Yuichi
Tsuda
Open Access
Abstract: Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (–OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.
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Dec 2022
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E01-JEM ARM 200CF
E02-JEM ARM 300CF
I14-Hard X-ray Nanoprobe
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Abstract: Introduction: Airless planetary bodies with surfaces exposed to the space environment are bombarded by electrons and protons from the solar wind and cosmic rays, as well as micrometeorites, resulting in space weathering [1]. Features of space weathering include partially amorphised grain surface rims, measuring up to
~100 nm thick, containing nanophase Fe metal (npFe0) particles, vesicular blistering, and solar flare tracks [1,2].
Space weathered samples collected by the JAXA Hayabusa spacecraft from asteroid Itokawa have previously been analysed using the I14 X-ray nanoprobe beamline at Diamond Light Source synchrotron, measuring Fe-K
X-ray absorption near-edge spectroscopy (XANES), and revealing an increased ferric-ferrous ratio (Fe3+/ΣFe) relative to their respective host grain mineralogy [3].
In this study, we seek to better understand the formation of space weathered lunar surface soil samples collected during the Apollo 17 mission, investigating the Fe-redox variations observed in the dominant silicate phase and the nano-grains of the space weathered rims using Fe-K XANES and EELS, with high-resolution STEM imaging.
Methods/Materials: The lunar sample number is 78481,29 - a surface sample collected from the top 1 cm of trench soils at Station 8 of Apollo 17 [4]. Three FIB lift-out sections have been extracted successfully from lunar grains identified to have space weathered surfaces. Two of the lunar grains were augite pyroxene, En81Fs16 and En85Fs12, and one olivine, Fa39.
Using the I14 X-ray Nanoprobe Beamline at Diamond, Fe-Kα XAS spectra are obtained from a series of XRF maps over the samples, with energies typically in the range 7000-7300 eV, with a higher energy resolution range over the XANES features (~7100-7150 eV). The XANES maps are processed using Mantis 2.3.02 [5], and isolated spectra normalized in Athena 0.8.056 [6]. By observing increasing shifts in the 1s→3d transition pre- absorption-edge peak centroid energy positions, the Fe-redox variations can be estimated between the sample host mineralogy and the space weathered zone, when compared to reference minerals of known ferric-ferrous
ratio (Fe3+/ΣFe).
A JEOL ARM200CF and JEOL JEM-ARM300CF instrument was used for EELS analyses and high-resolution STEM imaging respectively, at ePSIC in Diamond. EELS are performed using an accelerating voltage of 200 keV, current 15 μA, and 0.25eV/ch with a 5 mm EELS aperture, measuring linescans from the host to the space weathered zones to provide verification of the Fe-redox variation by observing the shifts in the Fe-Lα peaks.
Results: HR-STEM imaging confirmed the expected partial amorphisation and npFe0 particles (Fe0 metal confirmed observing lattice fringe spacings of ~2.06 Å) in the space weathered zones of all three lunar samples.
XANES mapping was able to identify the space weathered zone separate from the host grain mineralogy, and analyses of the XANES spectra from each revealed a consistent positive shift in the 1s→3d pre-edge centroid energy positions for the space weathered zone when compared to the host. Increases of up to ~0.23 eV in the space weathered (SW) zone, compared to the substrate host mineralogy of augite or olivine, suggests an
increase in ferric content in the space weathered zones up to ΔFe3+/ΣFe ~0.14 ±0.03. Positive shifts in the absorption edge positions for SW zones also support these results.
A total of 18 EELS linescans measured, at various locations along the space weathered rims in all three lunar samples, also shows a consistent increased shift in the Fe-L peak energy position. A positive shift in the EELS Fe-L peak position is indicative of increased ferric content, as shown by reference minerals measured including
Fe-rich olivine (Fe3+/ΣFe = 0.00) and magnetite (Fe3+/ΣFe = 0.67) with average EELS Fe-L peak positions of ~712.1 eV and ~713.6 eV respectively.
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Jul 2021
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E02-JEM ARM 300CF
I14-Hard X-ray Nanoprobe
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Open Access
Abstract: Space weathering due to the bombardment of electrons and solar wind upon the exposed lunar surface shows as an apparent spectral darkening and reddening in ground-based and lunar-orbital observations. Space weathered rims have been observed on soil surface samples, returned by the Apollo landings, featuring amorphized material and nanophase Fe metal (npFe⁰) particles formed due to the implantation of solar wind H⁺ ions reducing the host grain mineral oxides to form metal. Oxidation of these Fe particles has also been shown, and a suggested correlation between oxidation and lunar soil maturity.In this study, we investigate Fe-redox changes in the space weathered rims of Apollo 17 lunar surface soil samples, using TEM and X-ray nanoprobe Fe-K XANES.
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Sep 2020
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I18-Microfocus Spectroscopy
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Takaaki
Noguchi
,
John
Bridges
,
Leon
Hicks
,
Steve
Gurman
,
Makoto
Kimura
,
Takahito
Hashimoto
,
Mitsuru
Konno
,
John P.
Bradley
,
Ryuji
Okazaki
,
Masayuki
Uesugi
,
Toru
Yada
,
Yuzuru
Karouji
,
Masanao
Abe
,
Tatsuaki
Okada
,
Takuya
Mitsunari
,
Tomoki
Nakamura
,
Hiroyuki
Kagi
Diamond Proposal Number(s):
[8307]
Open Access
Abstract: Four Itokawa particles collected from the first touchdown site were mineralogically investigated by optical microscopy, micro-Raman (mu-Raman) spectrometry, scanning electron microscopy (SEM), electron microprobe analysis (EPMA), X-ray absorption spectroscopy (XAS), and transmission electron microscopy (TEM). Their mineralogy has an affinity to that of LL6 chondrites based on micro-Raman spectroscopy, EPMA, and XAS analyses. However, the space weathering rims on them are less developed than those observed on the Itokawa particles collected from the second touchdown site. Solar flare tracks are rarely observed in the four particles, whose number densities were lower than those observed in the Itokawa particles from the second touchdown site.
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Oct 2014
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I18-Microfocus Spectroscopy
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Abstract: The grains of Itokawa returned by the JAXA Hayabusa mission in 2010 showed mineralogical and isotopic affinities to LL5-6 chondrites [1,2,3]. If so, the redox state experienced by the grains in their parent body should be almost identical to that in LL5-6 chondrites. We measured the relative abundance of Fe3+ and Fe2+ ions in ferromagnesian silicates, which reflects the redox states, in grains from Itokawa and an LL chondrite. X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) are an X-ray Absorption Spectroscopy (XAS) spectroscopic technique which we use to compare Itokawa to chondrite meteorite samples.
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Feb 2013
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