TY - JOUR

T1 - Mixing between chemically variable primitive basalts creates and modifies crystal cargoes

AU - Neave, David A.

AU - Beckmann, Philipp

AU - Behrens, Harald

AU - Holtz, François

N1 - Funding Information: We thank Ulrich Kroll and Stefan Linsler for their help with maintaining IHPV equipment, and Renat Almeev and Chao Zhang for their help with EPMA. This work and D.A.N. were supported by the German Research Foundation (DFG; NE2097/1-1). D.A.N. was also supported Presidential Fellowship from the University of Manchester and a NERC Independent Research Fellowship (NE/T011106/1).

PY - 2021/12

Y1 - 2021/12

N2 - Basaltic crystal cargoes often preserve records of mantle-derived chemical variability that have been erased from their carrier liquids by magma mixing. However, the consequences of mixing between similarly primitive but otherwise chemically variable magmas remain poorly understood despite ubiquitous evidence of chemical variability in primary melt compositions and mixing-induced disequilibrium within erupted crystal cargoes. Here we report observations from magma–magma reaction experiments performed on analogues of primitive Icelandic lavas derived from distinct mantle sources to determine how their crystal cargoes respond to mixing-induced chemical disequilibrium. Chemical variability in our experimental products is controlled dominantly by major element diffusion in the melt that alters phase equilibria and triggers plagioclase resorption within regions that were initially plagioclase saturated. Isothermal mixing between chemically variable basaltic magmas may therefore play important but previously underappreciated roles in creating and modifying crystal cargoes by unlocking plagioclase-rich mushes and driving resorption, (re-)crystallisation and solid-state diffusion.

AB - Basaltic crystal cargoes often preserve records of mantle-derived chemical variability that have been erased from their carrier liquids by magma mixing. However, the consequences of mixing between similarly primitive but otherwise chemically variable magmas remain poorly understood despite ubiquitous evidence of chemical variability in primary melt compositions and mixing-induced disequilibrium within erupted crystal cargoes. Here we report observations from magma–magma reaction experiments performed on analogues of primitive Icelandic lavas derived from distinct mantle sources to determine how their crystal cargoes respond to mixing-induced chemical disequilibrium. Chemical variability in our experimental products is controlled dominantly by major element diffusion in the melt that alters phase equilibria and triggers plagioclase resorption within regions that were initially plagioclase saturated. Isothermal mixing between chemically variable basaltic magmas may therefore play important but previously underappreciated roles in creating and modifying crystal cargoes by unlocking plagioclase-rich mushes and driving resorption, (re-)crystallisation and solid-state diffusion.

UR - http://www.scopus.com/inward/record.url?scp=85115379893&partnerID=8YFLogxK

U2 - 10.1038/s41467-021-25820-z

DO - 10.1038/s41467-021-25820-z

M3 - Article

C2 - 34535680

AN - SCOPUS:85115379893

VL - 12

JO - Nature Communications

JF - Nature Communications

SN - 2041-1723

IS - 1

M1 - 5495

ER -