000005010 001__ 5010
000005010 005__ 20220920153506.0
000005010 0247_ $$2DOI$$a10.1029/2020JE006651
000005010 037__ $$aSCART-2020-0181
000005010 100__ $$aKnibbe, Jurrien
000005010 245__ $$aMercury's Interior Structure constrained by Density and P-wave Velocity Measurements of Liquid Fe-Si-C Alloys
000005010 260__ $$c2020
000005010 520__ $$aMeasurements of density by X-ray absorption and of P-wave velocity (VP) by ultrasonic techniques of liquid Fe-(<17wt%)Si-(<4.5wt%)C alloys at pressures up to 5.8 GPa are presented. They are used to develop a ternary Fe-Si-C mixing model, which is implemented in interior structure models of Mercury to characterize the Fe-Si-C liquid outer core. The interior structure models indicate that, unless Mercury’s mantle is dense and the core extremely hot, Mercury can only accommodate an inner core with a radius below 1200 km, consistent with reported dynamo simulations for Mercury’s magnetic field, if S and/or C are present in Mercury’s core at wt% level. Interior structure models with >14wt%Si in the core, inferred for Mercury by metal-silicate partitioning of an EH chondrite like bulk composition, are only possible if the obliquity of Mercury’s surface is near the upper limit of observational uncertainties (2.04±0.08 arcmin) and the mantle density is high (3.43–3.68 g·cm-3). Interior structure models calculated with the central obliquity value (2.04 arcmin) and with <7.5wt%Si in the core, which is within the range inferred from metal-silicate partitioning of CB chondrites, have mantle densities of 3.15–3.35 g·cm-3 and facilitate an inner core radius below 1200 km. Interior structure models with the obliquity of Mercury’s surface near the lower limit (1.96 arcmin) of observational uncertainty margins are only compatible with a low-density mantle (2.88 – 3.03 g·cm-3), <4wt%Si in the core, and >1600 km inner core radius. Implications of C and/or S in Mercury’s outer core for dynamo generation are briefly discussed.
000005010 536__ $$aMERCURYREFINEMENT/$$cMERCURYREFINEMENT/$$fMERCURYREFINEMENT
000005010 594__ $$aNO
000005010 6531_ $$aMercury
000005010 6531_ $$adensity
000005010 6531_ $$airon
000005010 6531_ $$asilicon
000005010 6531_ $$acarbon
000005010 6531_ $$aHigh-pressure
000005010 700__ $$aRivoldini, Attilio
000005010 700__ $$aLuginbuhl, Stefanie
000005010 700__ $$aNamur, Olivier
000005010 700__ $$aCharlier, Bernard
000005010 700__ $$aMezouar, Mohamed
000005010 700__ $$aSifre, David
000005010 700__ $$aBerndt, Jasper
000005010 700__ $$aKono, Yoshio
000005010 700__ $$aNeuville, Daniel
000005010 700__ $$avan Westrenen, Wim
000005010 700__ $$aVan Hoolst, Tim
000005010 773__ $$n1$$pJournal of Geophysical Research: Planets$$v126
000005010 8560_ $$fjurrien.knibbe@observatory.be
000005010 8564_ $$s3524830$$uhttp://publi2-as.oma.be/record/5010/files/Knibbe et al 2021.pdf$$yarticle file
000005010 8564_ $$s20478$$uhttp://publi2-as.oma.be/record/5010/files/Knibbe et al 2021.jpg?subformat=icon-180$$xicon-180$$yarticle file
000005010 8564_ $$s20660$$uhttp://publi2-as.oma.be/record/5010/files/Knibbe et al 2021.gif?subformat=icon$$xicon$$yarticle file
000005010 905__ $$apublished in
000005010 980__ $$aREFERD