Abstract
The Moon was initially covered by a magma ocean. Hydrogen detected in plagioclase of ferroan anorthosites, the only available samples directly crystallised from the lunar magma ocean (LMO), can be used to quantify LMO hydrogen content. We performed experiments to determine plagioclase-melt partition coefficients of water under LMO conditions with water contents of co-existing plagioclase and melt quantified using Fourier-Transform Infrared Spectroscopy. Results indicate lunar plagioclase can incorporate approximately one order of magnitude more water than previously assumed. Using measured water contents of lunar plagioclase, this suggests that ~100 μg/g H2O equivalent was present in the residual magma when 95 % of the initial LMO had crystallised. Our results constrain initial LMO water contents to ~ 5 μg/g H2O equivalent if water was conserved throughout LMO evolution. If on the other hand the initial LMO contained >1000 μg/g water as suggested by experiments on LMO crystallisation, >99 % hydrogen degassing occurred during the evolution of the LMO.
| Original language | English |
|---|---|
| Pages (from-to) | 14-19 |
| Number of pages | 6 |
| Journal | Geochemical Perspectives Letters |
| Volume | 10 |
| DOIs | |
| Publication status | Published - 1 Jan 2019 |
Fingerprint
Cite this
}
A lunar hygrometer based on plagioclase-melt partitioning of water. / Lin, Y. H.; Hui, H.; Li, Y.; Xu, Y.; Van Westrenen, W.
In: Geochemical Perspectives Letters, Vol. 10, 01.01.2019, p. 14-19.Research output: Contribution to Journal › Article › Academic › peer-review
TY - JOUR
T1 - A lunar hygrometer based on plagioclase-melt partitioning of water
AU - Lin, Y. H.
AU - Hui, H.
AU - Li, Y.
AU - Xu, Y.
AU - Van Westrenen, W.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - The Moon was initially covered by a magma ocean. Hydrogen detected in plagioclase of ferroan anorthosites, the only available samples directly crystallised from the lunar magma ocean (LMO), can be used to quantify LMO hydrogen content. We performed experiments to determine plagioclase-melt partition coefficients of water under LMO conditions with water contents of co-existing plagioclase and melt quantified using Fourier-Transform Infrared Spectroscopy. Results indicate lunar plagioclase can incorporate approximately one order of magnitude more water than previously assumed. Using measured water contents of lunar plagioclase, this suggests that ~100 μg/g H2O equivalent was present in the residual magma when 95 % of the initial LMO had crystallised. Our results constrain initial LMO water contents to ~ 5 μg/g H2O equivalent if water was conserved throughout LMO evolution. If on the other hand the initial LMO contained >1000 μg/g water as suggested by experiments on LMO crystallisation, >99 % hydrogen degassing occurred during the evolution of the LMO.
AB - The Moon was initially covered by a magma ocean. Hydrogen detected in plagioclase of ferroan anorthosites, the only available samples directly crystallised from the lunar magma ocean (LMO), can be used to quantify LMO hydrogen content. We performed experiments to determine plagioclase-melt partition coefficients of water under LMO conditions with water contents of co-existing plagioclase and melt quantified using Fourier-Transform Infrared Spectroscopy. Results indicate lunar plagioclase can incorporate approximately one order of magnitude more water than previously assumed. Using measured water contents of lunar plagioclase, this suggests that ~100 μg/g H2O equivalent was present in the residual magma when 95 % of the initial LMO had crystallised. Our results constrain initial LMO water contents to ~ 5 μg/g H2O equivalent if water was conserved throughout LMO evolution. If on the other hand the initial LMO contained >1000 μg/g water as suggested by experiments on LMO crystallisation, >99 % hydrogen degassing occurred during the evolution of the LMO.
UR - http://www.scopus.com/inward/record.url?scp=85068133404&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85068133404&partnerID=8YFLogxK
U2 - 10.7185/geochemlet.1908
DO - 10.7185/geochemlet.1908
M3 - Article
VL - 10
SP - 14
EP - 19
JO - Geochemical Perspectives Letters
JF - Geochemical Perspectives Letters
SN - 2410-339X
ER -