TY - JOUR

T1 - Diamond formation in an electric field under deep Earth conditions

AU - Palyanov, Yuri N.

AU - Borzdov, Yuri M.

AU - Sokol, Alexander G.

AU - Bataleva, Yuliya V.

AU - Kupriyanov, Igor N.

AU - Reutsky, Vadim N.

AU - Wiedenbeck, Michael

AU - Sobolev, Nikolay V.

N1 - Funding Information: This work was supported by the Russian Science Foundation under grant no. 19-17-00075. Publisher Copyright: Copyright © 2021 The Authors, some rights reserved. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/1/20

Y1 - 2021/1/20

N2 - Most natural diamonds are formed in Earth's lithospheric mantle; however, the exact mechanisms behind their genesis remain debated. Given the occurrence of electrochemical processes in Earth's mantle and the high electrical conductivity of mantle melts and fluids, we have developed a model whereby localized electric fields play a central role in diamond formation. Here, we experimentally demonstrate a diamond crystallization mechanism that operates under lithospheric mantle pressure-temperature conditions (6.3 and 7.5 gigapascals; 1300° to 1600°C) through the action of an electric potential applied across carbonate or carbonate-silicate melts. In this process, the carbonate-rich melt acts as both the carbon source and the crystallization medium for diamond, which forms in assemblage with mantle minerals near the cathode. Our results clearly demonstrate that electric fields should be considered a key additional factor influencing diamond crystallization, mantle mineral-forming processes, carbon isotope fractionation, and the global carbon cycle.

AB - Most natural diamonds are formed in Earth's lithospheric mantle; however, the exact mechanisms behind their genesis remain debated. Given the occurrence of electrochemical processes in Earth's mantle and the high electrical conductivity of mantle melts and fluids, we have developed a model whereby localized electric fields play a central role in diamond formation. Here, we experimentally demonstrate a diamond crystallization mechanism that operates under lithospheric mantle pressure-temperature conditions (6.3 and 7.5 gigapascals; 1300° to 1600°C) through the action of an electric potential applied across carbonate or carbonate-silicate melts. In this process, the carbonate-rich melt acts as both the carbon source and the crystallization medium for diamond, which forms in assemblage with mantle minerals near the cathode. Our results clearly demonstrate that electric fields should be considered a key additional factor influencing diamond crystallization, mantle mineral-forming processes, carbon isotope fractionation, and the global carbon cycle.

UR - http://www.scopus.com/inward/record.url?scp=85099911206&partnerID=8YFLogxK

U2 - 10.1126/sciadv.abb4644

DO - 10.1126/sciadv.abb4644

M3 - Article

C2 - 33523914

AN - SCOPUS:85099911206

VL - 7

JO - Science advances

JF - Science advances

SN - 2375-2548

IS - 4

M1 - eabb4644

ER -