Timing of the magmatic activity and upper crustal cooling of differentiated asteroid 4 Vesta

Jourdan, Fred; Kennedy, Trudi; Benedix, Gretchen; Eroğlu, Ela; Mayer, C.

doi:10.1016/j.gca.2020.01.036

Cited by 16 publications

(5 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Samples were irradiated for 40 h and subsequently analyzed at the Western Australian Argon Isotope Facility (WAAIF) using a MAP 215‐50 Mass Spectrometer equipped with a 10.4 µm CO 2 laser for stepped heating for 60 s, in accordance with Jourdan et al. (2020).…”

Section: Sample Allocation and Analytical Methodsmentioning

confidence: 99%

Mineralogy, petrology, geochemistry, and chronology of the Murrili (H5) meteorite fall: The third recovered fall from the Desert Fireball Network

Anderson

Benedix

Forman

et al. 2021

Meteorit & Planetary Scien

Self Cite

View full text Add to dashboard Cite

Murrili, the third meteorite recovered by the Desert Fireball Network, is analyzed using mineralogy, oxygen isotopes, bulk chemistry, physical properties, noble gases, and cosmogenic radionuclides. The modal mineralogy, bulk chemistry, magnetic susceptibility, physical properties, and oxygen isotopes of Murrili point to it being an H5 ordinary chondrite. It is heterogeneously shocked (S2–S5), depending on the method used to determine it, although Murrili is not obviously brecciated in texture. Cosmogenic radionuclides yield a cosmic ray exposure age of 6–8 Ma, and a pre‐atmospheric meteoroid size of 15–20 cm in radius. Murrili’s fall and subsequent month‐long embedment into the salt lake Kati Thanda significantly altered the whole rock, evident in its Mössbauer spectra, and visual inspection of cut sections. Murrili may have experienced minor, but subsequent, impacts after its formation 4475.3 ± 2.3 Ma, which left it heterogeneously shocked.

show abstract

Section: Sample Allocation and Analytical Methodsmentioning

confidence: 99%

Mineralogy, petrology, geochemistry, and chronology of the Murrili (H5) meteorite fall: The third recovered fall from the Desert Fireball Network

Anderson

Benedix

Forman

et al. 2021

Meteorit & Planetary Scien

Self Cite

View full text Add to dashboard Cite

show abstract

“…This is similar to U-Pb and 40 Ar/ 39 Ar results obtained for a larger asteroid such as Vesta, where eucrites from 15 to 20 km depth have been shown to cool down below the closure temperature of 40 Ar in plagioclase ca. 50 to 70 My after accretion (20,21). Therefore, considering the low shock-pressure (5 to 10 GPa) recorded by the ~4.2 Ga particles, the only other two conceivable scenarios that would cause a complete reset of the K/Ar systematics of the two particles involve either 1) a low-impact shock of 5 to 10 GPa in porous rubble pile material where the pressure wave can produce enough work through pore collapse to raise the temperature by few hundred degrees Celsius (13,22,23) or 2) unshocked (cold) particles brought in contact with shockheated material and insulated from space long enough to allow relatively slow cooling over hundred thousand to several millions of years (18).…”

Section: Discussionmentioning

confidence: 99%

Rubble pile asteroids are forever

Jourdan

Timms

Nakamura

et al. 2023

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

Rubble piles asteroids consist of reassembled fragments from shattered monolithic asteroids and are much more abundant than previously thought in the solar system. Although monolithic asteroids that are a kilometer in diameter have been predicted to have a lifespan of few 100 million years, it is currently not known how durable rubble pile asteroids are. Here, we show that rubble pile asteroids can survive ambient solar system bombardment processes for extremely long periods and potentially 10 times longer than their monolith counterparts. We studied three regolith dust particles recovered by the Hayabusa space probe from the rubble pile asteroid 25143 Itokawa using electron backscatter diffraction, time-of-flight secondary ion mass spectrometry, atom probe tomography, and 40 Ar/ 39 Ar dating techniques. Our results show that the particles have only been affected by shock pressure of ca. 5 to 15 GPa. Two particles have 40 Ar/ 39 Ar ages of 4,219 ± 35 and 4,149 ± 41 My and when combined with thermal and diffusion models; these results constrain the formation age of the rubble pile structure to ≥4.2 billion years ago. Such a long survival time for an asteroid is attributed to the shock-absorbent nature of rubble pile material and suggests that rubble piles are hard to destroy once they are created. Our results suggest that rubble piles are probably more abundant in the asteroid belt than previously thought and provide constrain to help develop mitigation strategies to prevent asteroid collisions with Earth.

show abstract

“…We note that the age of the Rheasilvia basin is debated: while the ~1 Ga age was initially based on dynamical simulations and Dawn observations (Marchi et al, 2012) and dynamical ages of the Vesta asteroid family (Marzari et al, 1996(Marzari et al, , 1999Milani et al, 2014), a crater-counting age based on a scaled lunar chronology estimates the basin to have formed ~3.5 Ga ago (Schmedemann et al, 2014). A similarly old age was also inferred from 40 Ar-39 Ar dating of eucrites which were interpreted as samples of rubble pile asteroids that formed from Rheasilvia ejecta (Jourdan et al, 2020;Kennedy et al, 2019). However, recent work by Schenk et al (2022) carefully reexamined the age of the basin and gives a young Rheasilvia event a higher probability than previous studies.…”

Section: Asteroidal Sources: Hed Meteoritesmentioning

confidence: 99%

“…Only one HED meteorite, Yamato-74097, has a bulk 40 Ar-39 Ar age between 1.0 and 1.3 Ga (Kaneoka et al, 1979). The old bulk 40 Ar ages of many HED meteorites determined in several studies (Bogard, 2011;Bogard & Garrison, 2003;Cohen, 2013;Jourdan et al, 2020;Kennedy et al, 2019) indicate that their radiogenic Ar clocks did not get reset during the Rheasilvia event, but do not preclude that meteorites were ejected at that time. The lack of impact melt deposits in the Rheasilvia basin indicates that the impact did not produce large amounts of melt and was of normal velocity (Marchi et al, 2012).…”

Section: Asteroidal Sources: Hed Meteoritesmentioning

confidence: 99%

Unusual sources of fossil micrometeorites deduced from relict chromite in the small size fraction in ~467 Ma old limestone

Heck,

Schmitz,

Ritter

et al. 2024

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Extraterrestrial chrome spinel and chromite extracted from the sedimentary rock record are relicts from coarse micrometeorites and rarely meteorites. They are studied to reconstruct the paleoflux of meteorites to the Earth and the collisional history of the asteroid belt. Minor element concentrations of Ti and V, and oxygen isotopic compositions of these relict minerals were used to classify the meteorite type they stem from, and thus to determine the relative meteorite group abundances through time. While coarse sediment‐dispersed extraterrestrial chrome‐spinel (SEC) grains from ordinary chondrites dominate through the studied time windows in the Phanerozoic, there are exceptions: We have shown that ~467 Ma ago, 1 Ma before the breakup of the L chondrite parent body (LCPB), more than half of the largest (>63 μm diameter) grains were achondritic and originated from differentiated asteroids in contrast to ordinary chondrites which dominated the meteorite flux throughout most of the past 500 Ma. Here, we present a new data set of oxygen isotopic compositions and elemental compositions of 136 grains of a smaller size fraction (32–63 μm) in ~467 Ma old pre‐LCPB limestone from the Lynna River section in western Russia, that was previously studied by elemental analysis. Our study constitutes the most comprehensive oxygen isotopic data set of sediment‐dispersed extraterrestrial chrome spinel to date. We also introduce a Raman spectroscopy‐based method to identify SEC grains and distinguish them from terrestrial chrome spinel with ~97% reliability. We calibrated the Raman method with the established approach using titanium and vanadium concentrations and oxygen isotopic compositions. We find that ordinary chondrites are approximately three times more abundant in the 32–63 μm fraction than achondrites. While abundances of achondrites compared to ordinary chondrites are lower in the 32–63 μm size fraction than in the >63 μm one, achondrites are approximately three times more abundant in the 32–62 μm fraction than they are in the present flux. We find that the sources of SEC grains vary for different grain sizes, mainly as a result of parent body thermal metamorphism. We conclude that the meteorite flux composition ~467 Ma ago ~1 Ma before the breakup of the LCPB was fundamentally different from today and from other time windows studied in the Phanerozoic, but that in contrast to the large size fraction ordinary chondrites dominated the flux in the small size fraction. The high abundance of ordinary chondrites in the studied samples is consistent with the findings based on coarse extraterrestrial chrome‐spinel from other time windows.

show abstract

Timing of the magmatic activity and upper crustal cooling of differentiated asteroid 4 Vesta

Cited by 16 publications

References 70 publications

Mineralogy, petrology, geochemistry, and chronology of the Murrili (H5) meteorite fall: The third recovered fall from the Desert Fireball Network

Mineralogy, petrology, geochemistry, and chronology of the Murrili (H5) meteorite fall: The third recovered fall from the Desert Fireball Network

Rubble pile asteroids are forever

Unusual sources of fossil micrometeorites deduced from relict chromite in the small size fraction in ~467 Ma old limestone

Contact Info

Product

Resources

About