{"type": "FeatureCollection", "features": [{"id": "10.1016/j.epsl.2017.04.002", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-15T16:16:12Z", "type": "Journal Article", "created": "2017-04-14", "title": "The origin of volatile element depletion in early solar system material: Clues from Zn isotopes in chondrules", "description": "Abstract   Volatile lithophile elements are depleted in the different planetary materials to various degrees, but the origin of these depletions is still debated. Stable isotopes of moderately volatile elements such as Zn can be used to understand the origin of volatile element depletions. Samples with significant volatile element depletions, including the Moon and terrestrial tektites, display heavy Zn isotope compositions (i.e. enrichment of 66Zn vs. 64Zn), consistent with kinetic Zn isotope fractionation during evaporation. However,  Luck et al. (2005)  found a negative correlation between      \u03b4    66     Zn and 1/[Zn] between CI, CM, CO, and CV chondrites, opposite to what would be expected if evaporation caused the Zn abundance variations among chondrite groups.  We have analyzed the Zn isotope composition of multiple samples of the major carbonaceous chondrite classes: CI (1), CM (4), CV (2), CO (4), CB (2), CH (2), CK (4), and CK/CR (1). The bulk chondrites define a negative correlation in a plot of      \u03b4    66     Zn vs 1/[Zn], confirming earlier results that Zn abundance variations among carbonaceous chondrites cannot be explained by evaporation. Exceptions are CB and CH chondrites, which display Zn systematics consistent with a collisional formation mechanism that created enrichment in heavy Zn isotopes relative to the trend defined by CI\u2013CK.  We further report Zn isotope analyses of chondrite components, including chondrules from Allende (CV3) and Mokoia (CV3), as well as an aliquot of Allende matrix. All chondrules are enriched in light Zn isotopes (\u223c500 ppm on 66Zn/64Zn) relative to the bulk, contrary to what would be expected if Zn were depleted during evaporation, on the other hand the matrix has a complementary heavy isotope composition. We report sequential leaching experiments in un-equilibrated ordinary chondrites, which show sulfides are isotopically heavy compared to silicates and the bulk meteorite by ca. +0.65 per mil on 66Zn/64Zn. We suggest isotopically heavy sulfides were removed from either chondrules or their precursors, thereby producing the light Zn isotope enrichments in chondrules.", "keywords": ["chondrules", "550", "protoplanetary disk", "551", "carbonaceous chondrites", "01 natural sciences", "volatiles", "[SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology", "[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry", "13. Climate action", "[SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry", "[SDU.STU.PL] Sciences of the Universe [physics]/Earth Sciences/Planetology", "zinc isotopes", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.epsl.2017.04.002"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Earth%20and%20Planetary%20Science%20Letters", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.epsl.2017.04.002", "name": "item", "description": "10.1016/j.epsl.2017.04.002", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.epsl.2017.04.002"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2017-06-01T00:00:00Z"}}, {"id": "10.1016/j.epsl.2017.04.022", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-04-15T16:16:12Z", "type": "Journal Article", "created": "2017-04-29", "title": "Testing the chondrule-rich accretion model for planetary embryos using calcium isotopes", "description": "Open AccessUnderstanding the composition of raw materials that formed the Earth is a crucial step towards understanding the formation of terrestrial planets and their bulk composition. Calcium is the fifth most abundant element in terrestrial planets and, therefore, is a key element with which to trace planetary composition. However, in order to use Ca isotopes as a tracer of Earth's accretion history, it is first necessary to understand the isotopic behavior of Ca during the earliest stages of planetary formation. Chondrites are some of the oldest materials of the Solar System, and the study of their isotopic composition enables understanding of how and in what conditions the Solar System formed. Here we present Ca isotope data for a suite of bulk chondrites as well as Allende (CV) chondrules. We show that most groups of carbonaceous chondrites (CV, CI, CR and CM) are significantly enriched in the lighter Ca isotopes ($\ufffd\ufffd^{44/40}Ca$ = +0.1 to +0.93 permill) compared with bulk silicate Earth ($\ufffd\ufffd^{44/40}Ca$ = +1.05 $ pm$ 0.04 permill, Huang et al., 2010) or Mars, while enstatite chondrites are indistinguishable from Earth in Ca isotope composition ($\ufffd\ufffd^{44/40}Ca$ = +0.91 to +1.06 permill). Chondrules from Allende are enriched in the heavier isotopes of Ca compared to the bulk and the matrix of the meteorite ($\ufffd\ufffd^{44/40}Ca$ = +1.00 to +1.21 permill). This implies that Earth and Mars have Ca isotope compositions that are distinct from most carbonaceous chondrites but that may be like chondrules. This Ca isotopic similarity between Earth, Mars, and chondrules is permissive of recent dynamical models of planetary formation that propose a chondrule-rich accretion model for planetary embryos.", "keywords": ["Earth and Planetary Astrophysics (astro-ph.EP)", "chondrules", "parent bodies", "calcium isotopes", "FOS: Physical sciences", "Earth", "01 natural sciences", "chondrites", "[SDU] Sciences of the Universe [physics]", "accretion", "13. Climate action", "10. No inequality", "Astrophysics - Earth and Planetary Astrophysics", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.epsl.2017.04.022"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Earth%20and%20Planetary%20Science%20Letters", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.epsl.2017.04.022", "name": "item", "description": "10.1016/j.epsl.2017.04.022", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.epsl.2017.04.022"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2017-07-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=chondrules&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=chondrules&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=chondrules&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=chondrules&offset=2", "hreflang": "en-US"}], "numberMatched": 2, "numberReturned": 2, "distributedFeatures": [], "timeStamp": "2026-04-16T12:33:36.703206Z"}