Basalts from the Chukchi Borderland: 40Ar/39Ar ages and feochemistry of submarine intraplate lavas dredged from the western Arctic Ocean

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F20%3A00000129" target="_blank" >RIV/00025798:_____/20:00000129 - isvavai.cz</a>

Výsledek na webu

<a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JB017604" target="_blank" >https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JB017604</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2019JB017604" target="_blank" >10.1029/2019JB017604</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Basalts from the Chukchi Borderland: 40Ar/39Ar ages and feochemistry of submarine intraplate lavas dredged from the western Arctic Ocean

Popis výsledku v původním jazyce

Submarine volcanism in the western Arctic Ocean, known as Amerasia Basin, is attributed to a mantle plume based on geophysics and meager geochemical evidence. Basaltic samples dredged from Chukchi Borderland within the basin have produced minimum 40Ar/39Ar ages for eruption at circa 118–112, circa 105–100, and circa 90–70 Ma, which we use to constrain tectonic models for basin opening. Major oxide and trace element concentrations and Sr, Nd, and Hf isotopic ratios of the lavas show that the circa 118–112 Ma samples from Northwind Ridge are tholeiites (low‐Ti tholeiite I) with low degrees of rare‐earthelement (REE) fractionation, high overall heavy rare‐earth element (HREE), and Mg# (Mg‐number), which suggests magma derivation from a garnet‐free source followed by minor crystal fractionation.Strontium, Nd, and Hf isotope systematics for these lavas and ratios of highly incompatible trace elements point toward a lithospheric source. Eruptions at circa 105–100 and circa 90–70 Ma, both at Healy Spur,produced two types of lavas: low‐Ti tholeiite II—which are generally older than high‐Ti tholeiite—both common in continental flood basalt (CFB) provinces and both with trace element abundance patternstypifying a garnet‐free source and significant crystal fractionation for the high‐Ti tholeiite. The isotope characteristics for both groups are common features of asthenospheric sources. Composition‐timerelationships for the lavas suggest inception of melting in the subcontinental lithospheric mantle (SCLM) — probably due to introduction of a heat source by a plume—followed later (at ca. 105–100 and ca. 90–70 Ma) by asthenospheric melting possibly triggered by plume rise.

Název v anglickém jazyce

Basalts from the Chukchi Borderland: 40Ar/39Ar ages and feochemistry of submarine intraplate lavas dredged from the western Arctic Ocean

Popis výsledku anglicky

Submarine volcanism in the western Arctic Ocean, known as Amerasia Basin, is attributed to a mantle plume based on geophysics and meager geochemical evidence. Basaltic samples dredged from Chukchi Borderland within the basin have produced minimum 40Ar/39Ar ages for eruption at circa 118–112, circa 105–100, and circa 90–70 Ma, which we use to constrain tectonic models for basin opening. Major oxide and trace element concentrations and Sr, Nd, and Hf isotopic ratios of the lavas show that the circa 118–112 Ma samples from Northwind Ridge are tholeiites (low‐Ti tholeiite I) with low degrees of rare‐earthelement (REE) fractionation, high overall heavy rare‐earth element (HREE), and Mg# (Mg‐number), which suggests magma derivation from a garnet‐free source followed by minor crystal fractionation.Strontium, Nd, and Hf isotope systematics for these lavas and ratios of highly incompatible trace elements point toward a lithospheric source. Eruptions at circa 105–100 and circa 90–70 Ma, both at Healy Spur,produced two types of lavas: low‐Ti tholeiite II—which are generally older than high‐Ti tholeiite—both common in continental flood basalt (CFB) provinces and both with trace element abundance patternstypifying a garnet‐free source and significant crystal fractionation for the high‐Ti tholeiite. The isotope characteristics for both groups are common features of asthenospheric sources. Composition‐timerelationships for the lavas suggest inception of melting in the subcontinental lithospheric mantle (SCLM) — probably due to introduction of a heat source by a plume—followed later (at ca. 105–100 and ca. 90–70 Ma) by asthenospheric melting possibly triggered by plume rise.

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

2020

Kód důvěrnosti údajů

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

Název periodika

Journal of Geophysical Research -Solid Earth

ISSN

2169-9313

e-ISSN

—

Svazek periodika

125

Číslo periodika v rámci svazku

7 : e2019JB017604

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

41

Strana od-do

nestránkováno

Kód UT WoS článku

000577118900012

EID výsledku v databázi Scopus

2-s2.0-85088570805