TY - JOUR
T1 - Thermal History of Matrix Forsterite Grains from Murchison Based on High-resolution Tomography
AU - Perotti, Giulia
AU - Sorensen, Henning O.
AU - Haack, Henning
AU - Andersen, Anja C.
AU - Sanchez, Dario Ferreira
AU - Van Kooten, Elishevah M.M.E.
AU - Tsai, Esther H.R.
AU - Dalby, Kim N.
AU - Holler, Mirko
AU - Grolimund, Daniel
AU - Hassenkam, Tue
N1 - Publisher Copyright:
© 2021. The American Astronomical Society. All rights reserved..
PY - 2021
Y1 - 2021
N2 - Protoplanetary disks are dust- and gas-rich structures surrounding protostars. Depending on the distance from the protostar, this dust is thermally processed to different degrees and accreted to form bodies of varying chemical compositions. The primordial accretion processes occurring in the early protoplanetary disk such as chondrule formation and metal segregation are not well understood. One way to constrain them is to study the morphology and composition of forsteritic grains from the matrix of carbonaceous chondrites. Here, we present high-resolution ptychographic X-ray nanotomography and multimodal chemical microtomography (X-ray diffraction and X-ray fluorescence) to reveal the early history of forsteritic grains extracted from the matrix of the Murchison CM2.5 chondrite. The 3D electron density maps revealed, at unprecedented resolution (64 nm), spherical inclusions containing Fe-Ni, very little silica-rich glass and void caps (i.e., volumes where the electron density is consistent with conditions close to vacuum) trapped in forsterite. The presence of the voids along with the overall composition, petrological textures, and shrinkage calculations is consistent with the grains experiencing one or more heating events with peak temperatures close to the melting point of forsterite (~2100 K), and subsequently cooled and contracted, in agreement with chondrule-forming conditions.
AB - Protoplanetary disks are dust- and gas-rich structures surrounding protostars. Depending on the distance from the protostar, this dust is thermally processed to different degrees and accreted to form bodies of varying chemical compositions. The primordial accretion processes occurring in the early protoplanetary disk such as chondrule formation and metal segregation are not well understood. One way to constrain them is to study the morphology and composition of forsteritic grains from the matrix of carbonaceous chondrites. Here, we present high-resolution ptychographic X-ray nanotomography and multimodal chemical microtomography (X-ray diffraction and X-ray fluorescence) to reveal the early history of forsteritic grains extracted from the matrix of the Murchison CM2.5 chondrite. The 3D electron density maps revealed, at unprecedented resolution (64 nm), spherical inclusions containing Fe-Ni, very little silica-rich glass and void caps (i.e., volumes where the electron density is consistent with conditions close to vacuum) trapped in forsterite. The presence of the voids along with the overall composition, petrological textures, and shrinkage calculations is consistent with the grains experiencing one or more heating events with peak temperatures close to the melting point of forsterite (~2100 K), and subsequently cooled and contracted, in agreement with chondrule-forming conditions.
U2 - 10.3847/1538-4357/ac26bc
DO - 10.3847/1538-4357/ac26bc
M3 - Journal article
AN - SCOPUS:85121793788
SN - 0004-637X
VL - 922
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 256
ER -