Enhanced mantle conductivity from sulfide minerals, southern Sierra Nevada, California

Mihai N Ducea, Stephen K. Park

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

Petrographic studies of peridotitic xenoliths entrained in late Quaternary basalts from beneath the southern Sierra Nevada have revealed the presence of accessory sulfide minerals along grain boundaries and fractures. Equilibration temperatures from the xenoliths are sufficiently high that the molten sulfides coexist with the basaltic melt. Sulfides are extremely conductive relative to the solid matrix or the basaltic melt, so a small fraction can increase the bulk conductivity of the mantle appreciably. Previous estimates of 2-5% partial melt from magnetotelluric measurements can be plausibly reduced to less than 1%. Such low melt percentages have longer residence times in the mantle and are more consistent with the volumetrically minor late Quaternary basalt flows and the primitive basalt compositions.

Original languageEnglish (US)
Pages (from-to)2405-2408
Number of pages4
JournalGeophysical Research Letters
Volume27
Issue number16
DOIs
StatePublished - 2000

Fingerprint

basalt
sulfides
Earth mantle
conductivity
minerals
sulfide
melt
mantle
mineral
accessories
grain boundary
grain boundaries
residence time
estimates
matrices
matrix
temperature

ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)

Cite this

Enhanced mantle conductivity from sulfide minerals, southern Sierra Nevada, California. / Ducea, Mihai N; Park, Stephen K.

In: Geophysical Research Letters, Vol. 27, No. 16, 2000, p. 2405-2408.

Research output: Contribution to journalArticle

@article{da051e8d47e34c3d884362e12454da96,
title = "Enhanced mantle conductivity from sulfide minerals, southern Sierra Nevada, California",
abstract = "Petrographic studies of peridotitic xenoliths entrained in late Quaternary basalts from beneath the southern Sierra Nevada have revealed the presence of accessory sulfide minerals along grain boundaries and fractures. Equilibration temperatures from the xenoliths are sufficiently high that the molten sulfides coexist with the basaltic melt. Sulfides are extremely conductive relative to the solid matrix or the basaltic melt, so a small fraction can increase the bulk conductivity of the mantle appreciably. Previous estimates of 2-5{\%} partial melt from magnetotelluric measurements can be plausibly reduced to less than 1{\%}. Such low melt percentages have longer residence times in the mantle and are more consistent with the volumetrically minor late Quaternary basalt flows and the primitive basalt compositions.",
author = "Ducea, {Mihai N} and Park, {Stephen K.}",
year = "2000",
doi = "10.1029/2000GL011565",
language = "English (US)",
volume = "27",
pages = "2405--2408",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "16",

}

TY - JOUR

T1 - Enhanced mantle conductivity from sulfide minerals, southern Sierra Nevada, California

AU - Ducea, Mihai N

AU - Park, Stephen K.

PY - 2000

Y1 - 2000

N2 - Petrographic studies of peridotitic xenoliths entrained in late Quaternary basalts from beneath the southern Sierra Nevada have revealed the presence of accessory sulfide minerals along grain boundaries and fractures. Equilibration temperatures from the xenoliths are sufficiently high that the molten sulfides coexist with the basaltic melt. Sulfides are extremely conductive relative to the solid matrix or the basaltic melt, so a small fraction can increase the bulk conductivity of the mantle appreciably. Previous estimates of 2-5% partial melt from magnetotelluric measurements can be plausibly reduced to less than 1%. Such low melt percentages have longer residence times in the mantle and are more consistent with the volumetrically minor late Quaternary basalt flows and the primitive basalt compositions.

AB - Petrographic studies of peridotitic xenoliths entrained in late Quaternary basalts from beneath the southern Sierra Nevada have revealed the presence of accessory sulfide minerals along grain boundaries and fractures. Equilibration temperatures from the xenoliths are sufficiently high that the molten sulfides coexist with the basaltic melt. Sulfides are extremely conductive relative to the solid matrix or the basaltic melt, so a small fraction can increase the bulk conductivity of the mantle appreciably. Previous estimates of 2-5% partial melt from magnetotelluric measurements can be plausibly reduced to less than 1%. Such low melt percentages have longer residence times in the mantle and are more consistent with the volumetrically minor late Quaternary basalt flows and the primitive basalt compositions.

UR - http://www.scopus.com/inward/record.url?scp=0034352656&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034352656&partnerID=8YFLogxK

U2 - 10.1029/2000GL011565

DO - 10.1029/2000GL011565

M3 - Article

AN - SCOPUS:0034352656

VL - 27

SP - 2405

EP - 2408

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

IS - 16

ER -