Igneous phenocrystic origin of K-feldspar megacrysts in granitic rocks from the Sierra Nevada batholith

Igneous Layering, Fractional Crystallization and Growth of Granitic Plutons: the Dolbel Batholith in SW Niger

This study reassesses the development of compositional layering during the growth of granitic plutons, with emphasis on fractional crystallization and its interaction with both injection and inflationrelated deformation. The Dolbel batholith (SW Niger) consists of 14, kilometre-sized plutons emplaced by pulsed magma inputs. Each pluton has a coarse-grained core and a peripheral layered series. ...

The age and origin of a thick ma®c±ultrama®c keel from beneath the Sierra Nevada batholith

We present evidence for a thick ( 100 km) sequence of cogenetic rocks which make up the root of the Sierra Nevada batholith of California. The Sierran magmatism produced tonalitic and granodioritic magmas which reside in the Sierra Nevada upperto midcrust, as well as deep eclogite facies crust/upper mantle ma®c±ultrama®c cumulates. Samples of the ma®c±ultrama®c sequence are preserved as xenolit...

41. K-metasomatism of plagioclase to produce microcline megacrysts in the Cathedral Peak granodiorite, Sierra Nevada, California, USA

Higgins (1999) proposed that microcline megacrysts in the Cathedral Peak granodiorite resulted from Ostwald ripening in which textural coarsening of earlier formed small K-feldspar crystals were sacrificed to feed the growth of a select few larger crystals. Textural evidence shows that Ostwald ripening did not occur, but, instead, the megacrysts resulted from K-replacement of broken plagioclase...

Hybridization of granitic magmas in the source: The origin of the Karakoram Batholith, Ladakh, NW India

Chronology of pluton emplacement and regional deformation in the southern Sierra Nevada batholith, California

Cretaceous plutonic rocks of the southern Sierra Nevada batholith between latitudes 35.5°N and 36°N lie in a strategic position that physically links shallow, subvolcanic levels of the batholith to lower-crustal (~35 km deep) batholithic rocks. This region preserves an oblique crustal section through the southern Sierra Nevada batholith. Prior studies have produced large U/Pb zircon data sets f...