Publication Date:
2023-10-26
Description:
The Piancaldoli ordinary chondrite fell in northern Italy on August 10, 1968.
Preliminary studies led to its classification as an LL3.4 unequilibrated ordinary chondrite.
However, recent developments in classification procedures have prompted us to re-examine
its mineralogical, petrographic, spectroscopic, chemical, and isotopic features in a multitechnique study. Raman spectra and magnetic properties indicate that Piancaldoli
experienced minimal thermal metamorphism, consistent with its high bulk hydrogen content
and the Cr contents of ferroan olivines in its type II chondrules. In combination with
findings of previous studies, our data thus confirm the variability of Cr contents in ferroan
olivines in type II chondrules as a proxy of thermal metamorphism. Furthermore, our
results reveal that Piancaldoli is less altered than previously reported and should be
reclassified as an LL3.10 unequilibrated ordinary chondrite. Our results also imply that the
bulk deuterium enrichment, as observed in Piancaldoli (LL3.10), Bishunpur (LL3.15), and
Semarkona (LL3.00), is a specific signature of the most primitive unequilibrated ordinary
chondrites. Based on our results, we propose that, to date, Piancaldoli is the second leastaltered unequilibrated ordinary chondrite fall after Semarkona. This work reiterates the
importance of meteorite collections worldwide as fundamental resources for studying the
formation conditions and evolution of our solar system.
Description:
Published
Description:
1924-1935
Description:
6A. Geochimica per l'ambiente e geologia medica
Description:
JCR Journal
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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