High pressure trace element partitioning between clinopyroxene and alkali basaltic melts

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F21%3A10432651" target="_blank" >RIV/00216208:11310/21:10432651 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6t02t.gwzk" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6t02t.gwzk</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.gca.2021.04.023" target="_blank" >10.1016/j.gca.2021.04.023</a>

Jazyk výsledku

angličtina

Název v původním jazyce

High pressure trace element partitioning between clinopyroxene and alkali basaltic melts

Popis výsledku v původním jazyce

We present new experimental data on major and trace element partition coefficients (D) between clinopyroxene and a K-basaltic melt from Procida Island (Campi Flegrei Volcanic District, south Italy). Time-series experiments were conducted at 0.8 GPa and 1080-1250 degrees C aiming to investigate the role of the crystallization kinetics on trace elements partitioning behaviour at a pressure relevant for deep magmatic reservoirs. Results indicate that large ion lithophile elements (LILE) are incompatible {e.g., D(Sr) &lt;= 0.15}, light rare elements {LREE; e.g., D(La) &lt;= 0.20} are always more incompatible than heavy rare elements (HREE), which in some cases result to be compatible with clinopyroxene {e.g., Due D(Dy) = 1.40}; high field strength elements (HFSE) are generally incompatible {D(HFSE) &lt;= 0.8}, while transition elements (TE) range from slightly incompatible {e.g., D(V) = 0.6} to highly compatible {e.g., D(Cr) = 63}. The calculated D values for LILEs, REEs, HFSEs, and TEs tend to decrease with the increase of temperature and to increase with increasing tetrahedrally-coordinated aluminium content, in agreement with the previous studies. Moreover, we observed the influence of the growth rate on the partition coefficients, with the highest D(REE) values calculated in the runs with the highest growth rate (similar to 10(-7) cm s(-1)), due to the less efficient rejection of incompatible elements during rapid crystal growth, that in this study is not linked to disequilibrium conditions, but to the presence of pre-existing nuclei. Additionally, the apparent increase in D(REE) values with time observed in some runs is not referable to a change in time but rather to the different degrees of polymerization, expressed as the ratios NBO/T of these melts, strictly related to a loss of Fe occurred during the experiments, and thus to a different melt viscosity. Finally, the application of the experimental clinopyroxene-melt partition coefficients highlights that the deepest step of the magmatic differentiation in the Campi Flegrei Volcanic District is represented by the fractionation of about 20-30% of a clinopyroxenitic mineral assemblage from a basaltic parental magma.

Název v anglickém jazyce

High pressure trace element partitioning between clinopyroxene and alkali basaltic melts

Popis výsledku anglicky

We present new experimental data on major and trace element partition coefficients (D) between clinopyroxene and a K-basaltic melt from Procida Island (Campi Flegrei Volcanic District, south Italy). Time-series experiments were conducted at 0.8 GPa and 1080-1250 degrees C aiming to investigate the role of the crystallization kinetics on trace elements partitioning behaviour at a pressure relevant for deep magmatic reservoirs. Results indicate that large ion lithophile elements (LILE) are incompatible {e.g., D(Sr) &lt;= 0.15}, light rare elements {LREE; e.g., D(La) &lt;= 0.20} are always more incompatible than heavy rare elements (HREE), which in some cases result to be compatible with clinopyroxene {e.g., Due D(Dy) = 1.40}; high field strength elements (HFSE) are generally incompatible {D(HFSE) &lt;= 0.8}, while transition elements (TE) range from slightly incompatible {e.g., D(V) = 0.6} to highly compatible {e.g., D(Cr) = 63}. The calculated D values for LILEs, REEs, HFSEs, and TEs tend to decrease with the increase of temperature and to increase with increasing tetrahedrally-coordinated aluminium content, in agreement with the previous studies. Moreover, we observed the influence of the growth rate on the partition coefficients, with the highest D(REE) values calculated in the runs with the highest growth rate (similar to 10(-7) cm s(-1)), due to the less efficient rejection of incompatible elements during rapid crystal growth, that in this study is not linked to disequilibrium conditions, but to the presence of pre-existing nuclei. Additionally, the apparent increase in D(REE) values with time observed in some runs is not referable to a change in time but rather to the different degrees of polymerization, expressed as the ratios NBO/T of these melts, strictly related to a loss of Fe occurred during the experiments, and thus to a different melt viscosity. Finally, the application of the experimental clinopyroxene-melt partition coefficients highlights that the deepest step of the magmatic differentiation in the Campi Flegrei Volcanic District is represented by the fractionation of about 20-30% of a clinopyroxenitic mineral assemblage from a basaltic parental magma.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Geochimica et Cosmochimica Acta

ISSN

0016-7037

e-ISSN

—

Svazek periodika

305

Číslo periodika v rámci svazku

July

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

24

Strana od-do

282-305

Kód UT WoS článku

000660120900015

EID výsledku v databázi Scopus

2-s2.0-85106284286