Mantle sources in the Arizona transition zone and global mantle heterogeneity

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Geology; (USA)

DOI:https://doi.org/10.1130/0091-7613(1990)018<1146:MSITAT>2.3.CO;2· OSTI ID:5796726

Cooper, J L; Hart, W K ^[1]

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1. Miami Univ., Oxford, OH (USA)

Isotopic and trace element data for basaltic lavas from the Springerville volcanic field, east-central Arizona, define three distinct mantle components involved in magma genesis in this part of the Colorado Plateau-Basin and Range transition zone. Correlated isotopic and trace element variations indicate that Springerville alkalic basalts were derived by mixing between components from a depleted asthenospheric source, an enriched lithospheric source, and a lithospheric source that exhibits radiogenic Pb and relatively nonradiogenic Sr characteristics. Tholeiitic basalts from the Springerville field equilibrated in the enriched mantle lithosphere and subsequently interacted with crust. Two of the distinct mantle components correspond to Zindler and Hart's proposed mantle isotopic end members PREMA and EMI, and the third mantle component suggests the possible existence of a HIMU-type reservoir. These observations have implications for the origin of enriched isotopic compositions in oceanic-island magmatism and support the theory that delamination of the subcontinental lithosphere is a feasible mechanism to recycle enriched components back into the mantle to be erupted at anomalous oceanic islands.

• OSTI ID: 5796726
• Journal Information: Geology; (USA), Journal Name: Geology; (USA) Vol. 18:11; ISSN GLGYB; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ALKALINE EARTH METALS
ARIZONA
BASALT
CHEMISTRY
CONTINENTAL CRUST
EARTH CRUST
EARTH MANTLE
ELEMENTS
FEDERAL REGION IX
GEOCHEMISTRY
GEOLOGIC MODELS
IGNEOUS ROCKS
ISLANDS
ISOTOPE RATIO
LAVA
LEAD
MAGMA
MAGMATISM
METALS
MIXING
NORTH AMERICA
OCEANIC CRUST
ORIGIN
ROCKS
SOURCE ROCKS
STRONTIUM
TRACE AMOUNTS
USA
VOLCANIC REGIONS
VOLCANIC ROCKS