Author: Callie Sendek
Publisher:
ISBN:
Category : Hafnium
Languages : en
Pages : 165
Book Description
The Late Cretaceous Mount Givens pluton, located in the central Sierra Nevada batholith, is noteworthy for its large size (~1400 km2) and relative compositional and textural homogeneity. The pluton is characterized by a 30 km wide, ellipse-shaped northern lobe (ca. 98-91 Ma) that connects with a long mass (ca. 95-91 Ma) about 15 km wide and extends 50 km SE. Zircon trace elements and d18O and eHf from a sample suite representative of the observable petrologic diversity of the pluton document significant heterogeneities. All zircons have high Ti-in-zircon model temperatures (850-1000 °C), pronounced negative Eu anomalies, and concave down MREE and HREE patterns, indicating initial melts were undersaturated in zircon and that zircon growth occurred during ascent or emplacement of Mount Givens magmas. Zircon trace elements record appreciable variation, and suggest that crystal transfer was ongoing throughout pluton growth. Significant variations in O and Hf isotopes require mixing of multiple, isotopically distinct sources. Longitudinal variation in both systems suggests increasing mantle contributions in the eastern portion of the pluton. A clear decrease in isotopic variability at all scales in post-95 Ma samples indicates that later magmas were more thoroughly mixed prior to emplacement. This increase in zircon isotopic homogeneity paired with the narrow timespan of intrusion hints that the inner portion of the northern lobe may have existed as a large melt reservoir.
Zircon Geochemical and Isotopic Constraints on the Evolution of the Mount Givens Pluton, Central Sierra Nevada Batholith
Author: Callie Sendek
Publisher:
ISBN:
Category : Hafnium
Languages : en
Pages : 165
Book Description
The Late Cretaceous Mount Givens pluton, located in the central Sierra Nevada batholith, is noteworthy for its large size (~1400 km2) and relative compositional and textural homogeneity. The pluton is characterized by a 30 km wide, ellipse-shaped northern lobe (ca. 98-91 Ma) that connects with a long mass (ca. 95-91 Ma) about 15 km wide and extends 50 km SE. Zircon trace elements and d18O and eHf from a sample suite representative of the observable petrologic diversity of the pluton document significant heterogeneities. All zircons have high Ti-in-zircon model temperatures (850-1000 °C), pronounced negative Eu anomalies, and concave down MREE and HREE patterns, indicating initial melts were undersaturated in zircon and that zircon growth occurred during ascent or emplacement of Mount Givens magmas. Zircon trace elements record appreciable variation, and suggest that crystal transfer was ongoing throughout pluton growth. Significant variations in O and Hf isotopes require mixing of multiple, isotopically distinct sources. Longitudinal variation in both systems suggests increasing mantle contributions in the eastern portion of the pluton. A clear decrease in isotopic variability at all scales in post-95 Ma samples indicates that later magmas were more thoroughly mixed prior to emplacement. This increase in zircon isotopic homogeneity paired with the narrow timespan of intrusion hints that the inner portion of the northern lobe may have existed as a large melt reservoir.
Publisher:
ISBN:
Category : Hafnium
Languages : en
Pages : 165
Book Description
The Late Cretaceous Mount Givens pluton, located in the central Sierra Nevada batholith, is noteworthy for its large size (~1400 km2) and relative compositional and textural homogeneity. The pluton is characterized by a 30 km wide, ellipse-shaped northern lobe (ca. 98-91 Ma) that connects with a long mass (ca. 95-91 Ma) about 15 km wide and extends 50 km SE. Zircon trace elements and d18O and eHf from a sample suite representative of the observable petrologic diversity of the pluton document significant heterogeneities. All zircons have high Ti-in-zircon model temperatures (850-1000 °C), pronounced negative Eu anomalies, and concave down MREE and HREE patterns, indicating initial melts were undersaturated in zircon and that zircon growth occurred during ascent or emplacement of Mount Givens magmas. Zircon trace elements record appreciable variation, and suggest that crystal transfer was ongoing throughout pluton growth. Significant variations in O and Hf isotopes require mixing of multiple, isotopically distinct sources. Longitudinal variation in both systems suggests increasing mantle contributions in the eastern portion of the pluton. A clear decrease in isotopic variability at all scales in post-95 Ma samples indicates that later magmas were more thoroughly mixed prior to emplacement. This increase in zircon isotopic homogeneity paired with the narrow timespan of intrusion hints that the inner portion of the northern lobe may have existed as a large melt reservoir.
Fifth Hutton Symposium
Author: Shuns? Ishihara
Publisher: Geological Society of America
ISBN: 0813723892
Category : Science
Languages : en
Pages : 391
Book Description
Publisher: Geological Society of America
ISBN: 0813723892
Category : Science
Languages : en
Pages : 391
Book Description
Isotopic U-Pb Ages of Zircon from the Granitoids of the Central Sierra Nevada, California
Author: T. W. Stern
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Uranium-lead ages on zircon from granitoids of the central part of the Sierra Nevada batholith and their bearing on the structure and history of the batholith.
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Uranium-lead ages on zircon from granitoids of the central part of the Sierra Nevada batholith and their bearing on the structure and history of the batholith.
Isotopic U-Pb Ages of Zircon from the Granitoids of the Central Sierra Nevada, California
Author:
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Uranium-lead ages on zircon from granitoids of the central part of the Sierra Nevada batholith and their bearing on the structure and history of the batholith.
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Uranium-lead ages on zircon from granitoids of the central part of the Sierra Nevada batholith and their bearing on the structure and history of the batholith.
Plutonism in the Central Part of the Sierra Nevada Batholith, California
Author: Paul C. Bateman
Publisher:
ISBN:
Category : Batholiths
Languages : en
Pages : 218
Book Description
A study of the structure, composition, and pre-Tertiary history of the Sierra Nevada batholith in the Mariposa 1 by 2 quadrangle.
Publisher:
ISBN:
Category : Batholiths
Languages : en
Pages : 218
Book Description
A study of the structure, composition, and pre-Tertiary history of the Sierra Nevada batholith in the Mariposa 1 by 2 quadrangle.
Transactions of the Royal Society of Edinburgh
Author:
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 584
Book Description
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 584
Book Description
Fifth Hutton Symposium
Author: Shunsō Ishihara
Publisher:
ISBN: 9780813723891
Category : Nature
Languages : en
Pages : 410
Book Description
Publisher:
ISBN: 9780813723891
Category : Nature
Languages : en
Pages : 410
Book Description
Zircon Fission-track Age Relations and Implications for the Mesozoic Thermal History of the Northern Sierra Nevada, California
Author: Stephen Paul Rowe
Publisher:
ISBN:
Category :
Languages : en
Pages : 634
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 634
Book Description
Isotopic U-Pb ages of zircon from the granitoids of the Central Sierra Nevada, California
Author: T. W. Stern
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 17
Book Description
Oxygen Isotope Ratios in Zircon and Garnet
Author: Raiza R. Quintero-Mendez
Publisher:
ISBN:
Category :
Languages : en
Pages : 262
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 262
Book Description