The aqueous alteration of CM chondrites, a review

The CM chondrites are samples of primitive water-rich asteroids formed during the early solar system. They record significant interaction between liquid water and silicate rock, resulting in a mineralogy dominated by hydrated secondary phases. Their similarity to the near-Earth asteroids Bennu and R...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Geochimica et cosmochimica acta 2021-04, Vol.299, p.219-256
Hauptverfasser: Suttle, M.D., King, A.J., Schofield, P.F., Bates, H., Russell, S.S.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
container_end_page 256
container_issue
container_start_page 219
container_title Geochimica et cosmochimica acta
container_volume 299
creator Suttle, M.D.
King, A.J.
Schofield, P.F.
Bates, H.
Russell, S.S.
description The CM chondrites are samples of primitive water-rich asteroids formed during the early solar system. They record significant interaction between liquid water and silicate rock, resulting in a mineralogy dominated by hydrated secondary phases. Their similarity to the near-Earth asteroids Bennu and Ryugu – targets of current sample return space missions – makes the analysis of CM chondrites essential to the interpretation of these enigmatic bodies. Here, we review the aqueous alteration history of the CM chondrite group. Initially, amorphous silicate, metal and sulphides within the matrix were converted into Fe-cronstedtite and tochilinite. Later, the serpentinization of refractory coarse-grained inclusions led to the addition of Mg to the fluid phase. This is reflected in the cation composition of secondary phases which evolved from Fe-rich to Mg-rich. Although most CM meteorites are classified as CM2 chondrites and retain some unaltered anhydrous silicates, a few completely altered CM1s exist (∼4.2% [Meteoritical Bulletin, 2021]). The extent of aqueous alteration can be quantified through various techniques, all of which trace the progression of secondary mineralization. Early attempts employed petrographic criteria to assign subtypes – most notably the Browning and Rubin scales have been widely adopted. Alternatively, bulk techniques evaluate alteration either by measuring the ratio of phyllosilicate to anhydrous silicate (this can be with X-ray diffraction [XRD] or infrared spectroscopy [IR]) or by measuring the combined H abundance/δD compositions. The degree of aqueous alteration appears to correlate with petrofabric strength (most likely arising due to shock deformation). This indicates that aqueous alteration may have been driven primarily by impact rather than by radiogenic heating. Alteration extent and bulk O-isotope compositions show a complex relationship. Among CM2 chondrites higher initial water contents correspond to more advanced alteration. However, the CM1s have lighter-than-expected bulk compositions. Although further analyses are needed these findings could suggest either differences in alteration conditions or initial isotopic compositions – the latter scenario implies that the CM1 chondrites formed on a separate asteroid from the CM2 chondrites. Secondary phases (primarily calcite) act as proxies for the conditions of aqueous alteration and demonstrate that alteration was prograde, with an early period at low temperatures (
doi_str_mv 10.1016/j.gca.2021.01.014
format Article
fullrecord <record><control><sourceid>elsevier_cross</sourceid><recordid>TN_cdi_crossref_primary_10_1016_j_gca_2021_01_014</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S0016703721000363</els_id><sourcerecordid>S0016703721000363</sourcerecordid><originalsourceid>FETCH-LOGICAL-a363t-16629a763fdd7721fd8c2b39ba6145b439aee3fe0073cfda81237b8f6b6d3f7b3</originalsourceid><addsrcrecordid>eNp9j81KxDAUhYMoWEcfwF0ewNYkt01aXEnxD0bcjOuQJjdOythq0lF8e1vGtXDgbu53OB8hl5wVnHF53Rdv1hSCCV6wJeURyXitRN5UAMckY_NTrhioU3KWUs8YU1XFMsI3W6Tmc4_jPlGzmzCaKYwDHT1tn6ndjoOLYcJ0RQ2N-BXw-5yceLNLePF3V-T1_m7TPubrl4en9nadG5Aw5VxK0RglwTunlODe1VZ00HRG8rLqSmgMInich4D1ztRcgOpqLzvpwKsOVoQfem0cU4ro9UcM7yb-aM704qx7PTvrxVmzJeXM3BwYnIfNY6NONuBg0YWIdtJuDP_Qv7alXgo</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>The aqueous alteration of CM chondrites, a review</title><source>Access via ScienceDirect (Elsevier)</source><creator>Suttle, M.D. ; King, A.J. ; Schofield, P.F. ; Bates, H. ; Russell, S.S.</creator><creatorcontrib>Suttle, M.D. ; King, A.J. ; Schofield, P.F. ; Bates, H. ; Russell, S.S.</creatorcontrib><description>The CM chondrites are samples of primitive water-rich asteroids formed during the early solar system. They record significant interaction between liquid water and silicate rock, resulting in a mineralogy dominated by hydrated secondary phases. Their similarity to the near-Earth asteroids Bennu and Ryugu – targets of current sample return space missions – makes the analysis of CM chondrites essential to the interpretation of these enigmatic bodies. Here, we review the aqueous alteration history of the CM chondrite group. Initially, amorphous silicate, metal and sulphides within the matrix were converted into Fe-cronstedtite and tochilinite. Later, the serpentinization of refractory coarse-grained inclusions led to the addition of Mg to the fluid phase. This is reflected in the cation composition of secondary phases which evolved from Fe-rich to Mg-rich. Although most CM meteorites are classified as CM2 chondrites and retain some unaltered anhydrous silicates, a few completely altered CM1s exist (∼4.2% [Meteoritical Bulletin, 2021]). The extent of aqueous alteration can be quantified through various techniques, all of which trace the progression of secondary mineralization. Early attempts employed petrographic criteria to assign subtypes – most notably the Browning and Rubin scales have been widely adopted. Alternatively, bulk techniques evaluate alteration either by measuring the ratio of phyllosilicate to anhydrous silicate (this can be with X-ray diffraction [XRD] or infrared spectroscopy [IR]) or by measuring the combined H abundance/δD compositions. The degree of aqueous alteration appears to correlate with petrofabric strength (most likely arising due to shock deformation). This indicates that aqueous alteration may have been driven primarily by impact rather than by radiogenic heating. Alteration extent and bulk O-isotope compositions show a complex relationship. Among CM2 chondrites higher initial water contents correspond to more advanced alteration. However, the CM1s have lighter-than-expected bulk compositions. Although further analyses are needed these findings could suggest either differences in alteration conditions or initial isotopic compositions – the latter scenario implies that the CM1 chondrites formed on a separate asteroid from the CM2 chondrites. Secondary phases (primarily calcite) act as proxies for the conditions of aqueous alteration and demonstrate that alteration was prograde, with an early period at low temperatures (&lt;70 °C), while later alteration operated at higher temperatures of 100–250 °C. Estimates for the initial water-to-rock ratios (W/R) vary between 0.2–0.7. They are based either on isotopic mass balance or mineral stoichiometry calculations – variability reflects uncertainties in the primordial water and protolith compositions and whether alteration was open or closed system. Some CM chondrites (&lt;36%) experienced a later episode of post-hydration thermal metamorphism, enduring peak temperatures &lt;900 °C and resulting in a dehydrated mineralogy and depleted volatile element abundances. Heating was likely short-duration and caused by impact events. The presence of CM chondrite material embedded in other meteorites, their prominence among the micrometeorite flux and the link between CMs and rubble-pile C-type near-Earth asteroids (e.g. Bennu and Ryugu) implies that the CM parent body was disrupted, leaving second-generation CM asteroids to supply material to Earth.</description><identifier>ISSN: 0016-7037</identifier><identifier>EISSN: 1872-9533</identifier><identifier>DOI: 10.1016/j.gca.2021.01.014</identifier><language>eng</language><publisher>Elsevier Ltd</publisher><subject>Aqueous alteration ; Bennu ; C-type asteroids ; CM chondrites ; Ryugu</subject><ispartof>Geochimica et cosmochimica acta, 2021-04, Vol.299, p.219-256</ispartof><rights>2021 The Authors</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-a363t-16629a763fdd7721fd8c2b39ba6145b439aee3fe0073cfda81237b8f6b6d3f7b3</citedby><cites>FETCH-LOGICAL-a363t-16629a763fdd7721fd8c2b39ba6145b439aee3fe0073cfda81237b8f6b6d3f7b3</cites><orcidid>0000-0003-0902-0588 ; 0000-0002-0469-9483 ; 0000-0001-6113-5417</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://dx.doi.org/10.1016/j.gca.2021.01.014$$EHTML$$P50$$Gelsevier$$Hfree_for_read</linktohtml><link.rule.ids>315,781,785,3551,27926,27927,45997</link.rule.ids></links><search><creatorcontrib>Suttle, M.D.</creatorcontrib><creatorcontrib>King, A.J.</creatorcontrib><creatorcontrib>Schofield, P.F.</creatorcontrib><creatorcontrib>Bates, H.</creatorcontrib><creatorcontrib>Russell, S.S.</creatorcontrib><title>The aqueous alteration of CM chondrites, a review</title><title>Geochimica et cosmochimica acta</title><description>The CM chondrites are samples of primitive water-rich asteroids formed during the early solar system. They record significant interaction between liquid water and silicate rock, resulting in a mineralogy dominated by hydrated secondary phases. Their similarity to the near-Earth asteroids Bennu and Ryugu – targets of current sample return space missions – makes the analysis of CM chondrites essential to the interpretation of these enigmatic bodies. Here, we review the aqueous alteration history of the CM chondrite group. Initially, amorphous silicate, metal and sulphides within the matrix were converted into Fe-cronstedtite and tochilinite. Later, the serpentinization of refractory coarse-grained inclusions led to the addition of Mg to the fluid phase. This is reflected in the cation composition of secondary phases which evolved from Fe-rich to Mg-rich. Although most CM meteorites are classified as CM2 chondrites and retain some unaltered anhydrous silicates, a few completely altered CM1s exist (∼4.2% [Meteoritical Bulletin, 2021]). The extent of aqueous alteration can be quantified through various techniques, all of which trace the progression of secondary mineralization. Early attempts employed petrographic criteria to assign subtypes – most notably the Browning and Rubin scales have been widely adopted. Alternatively, bulk techniques evaluate alteration either by measuring the ratio of phyllosilicate to anhydrous silicate (this can be with X-ray diffraction [XRD] or infrared spectroscopy [IR]) or by measuring the combined H abundance/δD compositions. The degree of aqueous alteration appears to correlate with petrofabric strength (most likely arising due to shock deformation). This indicates that aqueous alteration may have been driven primarily by impact rather than by radiogenic heating. Alteration extent and bulk O-isotope compositions show a complex relationship. Among CM2 chondrites higher initial water contents correspond to more advanced alteration. However, the CM1s have lighter-than-expected bulk compositions. Although further analyses are needed these findings could suggest either differences in alteration conditions or initial isotopic compositions – the latter scenario implies that the CM1 chondrites formed on a separate asteroid from the CM2 chondrites. Secondary phases (primarily calcite) act as proxies for the conditions of aqueous alteration and demonstrate that alteration was prograde, with an early period at low temperatures (&lt;70 °C), while later alteration operated at higher temperatures of 100–250 °C. Estimates for the initial water-to-rock ratios (W/R) vary between 0.2–0.7. They are based either on isotopic mass balance or mineral stoichiometry calculations – variability reflects uncertainties in the primordial water and protolith compositions and whether alteration was open or closed system. Some CM chondrites (&lt;36%) experienced a later episode of post-hydration thermal metamorphism, enduring peak temperatures &lt;900 °C and resulting in a dehydrated mineralogy and depleted volatile element abundances. Heating was likely short-duration and caused by impact events. The presence of CM chondrite material embedded in other meteorites, their prominence among the micrometeorite flux and the link between CMs and rubble-pile C-type near-Earth asteroids (e.g. Bennu and Ryugu) implies that the CM parent body was disrupted, leaving second-generation CM asteroids to supply material to Earth.</description><subject>Aqueous alteration</subject><subject>Bennu</subject><subject>C-type asteroids</subject><subject>CM chondrites</subject><subject>Ryugu</subject><issn>0016-7037</issn><issn>1872-9533</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2021</creationdate><recordtype>article</recordtype><recordid>eNp9j81KxDAUhYMoWEcfwF0ewNYkt01aXEnxD0bcjOuQJjdOythq0lF8e1vGtXDgbu53OB8hl5wVnHF53Rdv1hSCCV6wJeURyXitRN5UAMckY_NTrhioU3KWUs8YU1XFMsI3W6Tmc4_jPlGzmzCaKYwDHT1tn6ndjoOLYcJ0RQ2N-BXw-5yceLNLePF3V-T1_m7TPubrl4en9nadG5Aw5VxK0RglwTunlODe1VZ00HRG8rLqSmgMInich4D1ztRcgOpqLzvpwKsOVoQfem0cU4ro9UcM7yb-aM704qx7PTvrxVmzJeXM3BwYnIfNY6NONuBg0YWIdtJuDP_Qv7alXgo</recordid><startdate>20210415</startdate><enddate>20210415</enddate><creator>Suttle, M.D.</creator><creator>King, A.J.</creator><creator>Schofield, P.F.</creator><creator>Bates, H.</creator><creator>Russell, S.S.</creator><general>Elsevier Ltd</general><scope>6I.</scope><scope>AAFTH</scope><scope>AAYXX</scope><scope>CITATION</scope><orcidid>https://orcid.org/0000-0003-0902-0588</orcidid><orcidid>https://orcid.org/0000-0002-0469-9483</orcidid><orcidid>https://orcid.org/0000-0001-6113-5417</orcidid></search><sort><creationdate>20210415</creationdate><title>The aqueous alteration of CM chondrites, a review</title><author>Suttle, M.D. ; King, A.J. ; Schofield, P.F. ; Bates, H. ; Russell, S.S.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-a363t-16629a763fdd7721fd8c2b39ba6145b439aee3fe0073cfda81237b8f6b6d3f7b3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2021</creationdate><topic>Aqueous alteration</topic><topic>Bennu</topic><topic>C-type asteroids</topic><topic>CM chondrites</topic><topic>Ryugu</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Suttle, M.D.</creatorcontrib><creatorcontrib>King, A.J.</creatorcontrib><creatorcontrib>Schofield, P.F.</creatorcontrib><creatorcontrib>Bates, H.</creatorcontrib><creatorcontrib>Russell, S.S.</creatorcontrib><collection>ScienceDirect Open Access Titles</collection><collection>Elsevier:ScienceDirect:Open Access</collection><collection>CrossRef</collection><jtitle>Geochimica et cosmochimica acta</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Suttle, M.D.</au><au>King, A.J.</au><au>Schofield, P.F.</au><au>Bates, H.</au><au>Russell, S.S.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>The aqueous alteration of CM chondrites, a review</atitle><jtitle>Geochimica et cosmochimica acta</jtitle><date>2021-04-15</date><risdate>2021</risdate><volume>299</volume><spage>219</spage><epage>256</epage><pages>219-256</pages><issn>0016-7037</issn><eissn>1872-9533</eissn><abstract>The CM chondrites are samples of primitive water-rich asteroids formed during the early solar system. They record significant interaction between liquid water and silicate rock, resulting in a mineralogy dominated by hydrated secondary phases. Their similarity to the near-Earth asteroids Bennu and Ryugu – targets of current sample return space missions – makes the analysis of CM chondrites essential to the interpretation of these enigmatic bodies. Here, we review the aqueous alteration history of the CM chondrite group. Initially, amorphous silicate, metal and sulphides within the matrix were converted into Fe-cronstedtite and tochilinite. Later, the serpentinization of refractory coarse-grained inclusions led to the addition of Mg to the fluid phase. This is reflected in the cation composition of secondary phases which evolved from Fe-rich to Mg-rich. Although most CM meteorites are classified as CM2 chondrites and retain some unaltered anhydrous silicates, a few completely altered CM1s exist (∼4.2% [Meteoritical Bulletin, 2021]). The extent of aqueous alteration can be quantified through various techniques, all of which trace the progression of secondary mineralization. Early attempts employed petrographic criteria to assign subtypes – most notably the Browning and Rubin scales have been widely adopted. Alternatively, bulk techniques evaluate alteration either by measuring the ratio of phyllosilicate to anhydrous silicate (this can be with X-ray diffraction [XRD] or infrared spectroscopy [IR]) or by measuring the combined H abundance/δD compositions. The degree of aqueous alteration appears to correlate with petrofabric strength (most likely arising due to shock deformation). This indicates that aqueous alteration may have been driven primarily by impact rather than by radiogenic heating. Alteration extent and bulk O-isotope compositions show a complex relationship. Among CM2 chondrites higher initial water contents correspond to more advanced alteration. However, the CM1s have lighter-than-expected bulk compositions. Although further analyses are needed these findings could suggest either differences in alteration conditions or initial isotopic compositions – the latter scenario implies that the CM1 chondrites formed on a separate asteroid from the CM2 chondrites. Secondary phases (primarily calcite) act as proxies for the conditions of aqueous alteration and demonstrate that alteration was prograde, with an early period at low temperatures (&lt;70 °C), while later alteration operated at higher temperatures of 100–250 °C. Estimates for the initial water-to-rock ratios (W/R) vary between 0.2–0.7. They are based either on isotopic mass balance or mineral stoichiometry calculations – variability reflects uncertainties in the primordial water and protolith compositions and whether alteration was open or closed system. Some CM chondrites (&lt;36%) experienced a later episode of post-hydration thermal metamorphism, enduring peak temperatures &lt;900 °C and resulting in a dehydrated mineralogy and depleted volatile element abundances. Heating was likely short-duration and caused by impact events. The presence of CM chondrite material embedded in other meteorites, their prominence among the micrometeorite flux and the link between CMs and rubble-pile C-type near-Earth asteroids (e.g. Bennu and Ryugu) implies that the CM parent body was disrupted, leaving second-generation CM asteroids to supply material to Earth.</abstract><pub>Elsevier Ltd</pub><doi>10.1016/j.gca.2021.01.014</doi><tpages>38</tpages><orcidid>https://orcid.org/0000-0003-0902-0588</orcidid><orcidid>https://orcid.org/0000-0002-0469-9483</orcidid><orcidid>https://orcid.org/0000-0001-6113-5417</orcidid><oa>free_for_read</oa></addata></record>
fulltext fulltext
identifier ISSN: 0016-7037
ispartof Geochimica et cosmochimica acta, 2021-04, Vol.299, p.219-256
issn 0016-7037
1872-9533
language eng
recordid cdi_crossref_primary_10_1016_j_gca_2021_01_014
source Access via ScienceDirect (Elsevier)
subjects Aqueous alteration
Bennu
C-type asteroids
CM chondrites
Ryugu
title The aqueous alteration of CM chondrites, a review
url https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-12-17T17%3A11%3A18IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-elsevier_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=The%20aqueous%20alteration%20of%20CM%20chondrites,%20a%20review&rft.jtitle=Geochimica%20et%20cosmochimica%20acta&rft.au=Suttle,%20M.D.&rft.date=2021-04-15&rft.volume=299&rft.spage=219&rft.epage=256&rft.pages=219-256&rft.issn=0016-7037&rft.eissn=1872-9533&rft_id=info:doi/10.1016/j.gca.2021.01.014&rft_dat=%3Celsevier_cross%3ES0016703721000363%3C/elsevier_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/&rft_els_id=S0016703721000363&rfr_iscdi=true