An Individual Development Plan (IDP) is a personal action plan. IDPs can be used to set academic goals, explore career opportunities, and develop skills. During the 2022-23 academic year, we implemented IDPs with two groups in university settings: (1) graduate students and post-docs in the NASA-funded ICE-Five-O project; and (2) undergraduate and graduate students at the University of Hawai‘i. Twenty-four participants and their mentors rated various aspects of the IDP program on a scale of 1 (negative) to 5 (positive). Results were strongly positive, with means ranging from 4.1 to 4.8 for participants and from 4.2 to 4.6 for mentors. Overall, 92% of participants reported that they would recommend IDPs to their peers, and 94% of mentors reported that they would recommend IDPs as a mentoring tool. Although relatively few people (15%, or 31 of 207 eligible trainees) opted to participate, results of the pilot clearly show that those who created an IDP found the experience valuable. Future efforts will focus on maximizing participation.

Remnant extraterrestrial chrome spinels from terrestrial sediments provide information on how the mixture of meteoritic materials falling to Earth has changed over Earth’s history. The parent meteorite type of each grain can be identified by characteristic elemental and oxygen‐isotope abundances. Some meteorite types can be difficult to classify because their chrome‐spinel compositional ranges overlap. Silicate inclusions within chrome spinels of modern ordinary chondrites have been shown to have discriminating power among meteorite subclasses. We employed energy‐dispersive X‐ray spectroscopy in a scanning electron microscope (SEM) and in a (scanning) transmission electron microscope (S/TEM) to investigate inclusions in chrome‐spinel grains from Ordovician and Jurassic sediments. Unaltered Ordovician inclusions allowed us to establish the size limits for reliable SEM analysis of inclusions. The Jurassic grains were more altered, but the use of STEM techniques on small inclusions (<3 μm diameter at their polished surfaces) allowed us to determine chemical compositions and mineral structures of inclusions in three chrome spinels. The parent meteorite type was determined for one Jurassic grain based on its inclusion compositions. Our study confirms that silicate inclusions can be used to classify parent meteorite types of chrome‐spinel grains, but the size of the inclusions and the complex effects of terrestrial alteration must be taken into account. During our study, we also found some interesting exsolution phenomena in the host chrome‐spinel grains.

JURASSIC REVEALED BY STEM-EDX. C. E. Caplan1,2*, G. R. Huss2, H. A. Ishii2, J. P. Bradley2, P. Eschbach3, B. Schmitz4,2, and K. Nagashima2, 1Department of Geology and Geophysics, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 2Hawai‘i Institute of Geophysics and Planetology, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 3Electron Microscopy Facility, Oregon State University, 2900 SW Campus Way, Corvallis, OR 97331, 4Department of Physics, University of Lund, P.O. Box 118, Lund SE-22100, Sweden. *caplance@hawaii.edu.

We have recently begun a major collaborative project to determine the relative abundances of meteorite types over geologic time using remnant extraterrestrial chrome-spinels. These grains resist weathering and are preserved in terrestrial limestone [1]. The assignment of chrome-spinels to meteorite types requires multiple tools and techniques. The combination of chemical composition, oxygen isotopes, and the mineralogy and chemical composition of inclusions within the chrome-spinel define the host meteorite type. This work concentrates on samples from the Jurassic (~160 Myr ago).

REMNANT CHROME-SPINELS. C. E. Caplan1,2*, G. R. Huss2, B. Schmitz3,2, and K. Nagashima2, 1Department of Geology and Geophysics, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 2Hawai‘i Institute of Geophysics and Planetology, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 3Department of Physics, University of Lund, P.O. Box 118, Lund SE-22100, Sweden. *caplance@hawaii.edu.

From mid-Ordovician ∼470 Myr-old limestone >100 fossil L-chondritic meteorites have been recovered, representing the markedly enhanced flux of meteorites to Earth following the breakup of the L-chondrite parent body. Recently one anomalous meteorite, Österplana 065 (Öst 65), was found in the same beds that yield L chondrites. The cosmic-ray exposure age of Öst 65 shows that it may be a fragment of the impactor that broke up the L-chondrite parent body. Here we show that in a chromium versus oxygen-isotope plot Öst 65 falls outside all fields encompassing the known meteorite types. This may be the first documented example of an ‘extinct’ meteorite, that is, a meteorite type that does not fall on Earth today because its parent body has been consumed by collisions. The meteorites found on Earth today apparently do not give a full representation of the kind of bodies in the asteroid belt ∼500 Myr ago.

JURASSIC SEDIMENTS IN CARCABUEY, SPAIN. C. E. Caplan1,2*, G. R. Huss2, B. Schmitz3,2, and K. Nagashima2, 1Department of Geology and Geophysics, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 2Hawai‘i Institute of Geophysics and Planetology, University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI 96822, 3Department of Physics, University of Lund, P.O. Box 118, Lund SE-22100, Sweden. *caplance@hawaii.edu.