Mineralogical and chemical evolution of a rare-element granite-pegmatite system: Harney Peak Granite, Black Hills, South Dakota

Shearer, C. K.; Papike, J. J.; Laul, J. C.

doi:10.1016/0016-7037(87)90062-7

Cited by 75 publications

(21 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Enrichment in F, B and H 2 O in the Betliar granitic magmas can be explained by fractional crystallization of initially enriched parental melts (Thomas et al 2005). During solidification, a reaction between biotite and B-bearing silicate melt was proposed to give rise to tourmaline (Shearer et al 1987). The stability of tourmaline is further enhanced by low Ti abundances, which stabilize tourmaline over biotite (Nabelek et al 1992).…”

Section: Tourmaline As Results Of Fractionation and High Volatile Fluxmentioning

confidence: 99%

The granite system near Betliar village (Gemeric Superunit, Western Carpathians): evolution of a composite silicic reservoir

Kubiś¹,

Broska²

2012

J. Geosci.

View full text Add to dashboard Cite

Boron-and fluorine-rich highly evolved granites in the Betliar area (Gemeric Unit, Western Carpathians) represent composite intrusion that formed probably during two distinct magmatic episodes. During the first stage, evolved granitic magma originating from an underlying volatile-rich reservoir intruded into an open fault system in the form of sill-like bodies and crystallized as equigranular or medium-to fine-grained rocks. The subsequent volatile flux enhanced postmagmatic alterations of the solidified granites and led to the formation of greisens with elevated amounts of tourmaline and Nb-Ta-W-Th phases. During the second stage, magma from a deeper magmatic reservoir intruded as a mush containing K-feldspar, albite, mica and quartz phenocrysts and gave rise to porphyritic granites. Partial dissolution and corrosion of the phenocrysts was enhanced by a pressure drop during emplacement of the porphyritic granites into middle-crustal level where the volatile-rich residual melt rapidly crystallized and is now preserved as quartz-albite-K-feldspar matrix with tourmaline and other accessories. Monazite and zircon geochronology indicates that the process occurred during Middle and Late Permian, and possibly extended to Early Triassic.

show abstract

Section: Tourmaline As Results Of Fractionation and High Volatile Fluxmentioning

confidence: 99%

The granite system near Betliar village (Gemeric Superunit, Western Carpathians): evolution of a composite silicic reservoir

Kubiś¹,

Broska²

2012

J. Geosci.

View full text Add to dashboard Cite

show abstract

“…Therefore, the more evolved pegmatites correspond to the later stages of fractional crystallization, and are enriched in incompatible elements. Some authors have proposed a metamorphicanatectic model for the genesis of rare-element pegmatites (Stewart, 1978;Norton, 1981;Sokolov, 1981;Shmakin, 1983;Shearer et al, 1987a). A partial melting model involves varying degrees of partial melting to generate the broad compositional range of many of the granitepegmatite fields.…”

Section: Trace Element Modellingmentioning

confidence: 99%

The granitic pegmatites of the Fregeneda area (Salamanca, Spain): characteristics and petrogenesis

Roda-Robles

Pérez²,

Roldán³

et al. 1999

Mineral. mag.

View full text Add to dashboard Cite

Pegmatites of the Fregeneda area, Salamanca, Spain, show a zonal distribution, from barren to enrichment in Li, Sn, Rb, Nb>Ta, B and P. They intrude pre-Ordovician metasediments which were metamorphosed to sillimanite-zone conditions near the Lumbrales granite. Field, mineralogical and petrographic data show the following zonal sequence from the granite outward: (1) barren pegmatites (pegmatites T1, T2, T3 and T4) with quartz, K-feldspar > albite, muscovite, tourmaline _+ andalusite __ garnet; (2) intermediate pegmatites (types T5 and T6), characterized by the occurrence of beryl and Fe-Mn-Li phosphates; and (3) fertile pegmatites (dykes T7 and T8), with lepidolite, cassiterite, columbite, albite > K-feldspar, montebrasite and spodumene.Tourmaline from different pegmatites shows significant compositional variations. Trace element variations in mica and K-feldspar suggest that the origin of the different pegmatitic bodies may be explained by three different paths of fractional crystallization of melts generated by partial melting of quartzo-feldspathic rocks.

show abstract

“…Although Guidotti et al (1986) and Wise and Francis (1992) suggested a cogenetic relationship among the pegmatites of the Sebago area, their claim is unsupported by geochemical, geochronological or isotopic data which would aid in evaluating potential links between granites and groups of diverse pegmatites even though physical transitions may not exist (e.g., Shearer et al 1987). A rigorous investigation addressing the rare-element enrichment of the pegmatite population and their possible genetic connections to neighboring granitic intrusions (e.g., Sebago and Songo plutons) is not yet available.…”

Section: Introductionmentioning

confidence: 99%

Mineral chemistry, petrology and geochemistry of the Sebago granite-pegmatite system, southern Maine, USA

Wise¹,

Brown²

2012

J. Geosci.

View full text Add to dashboard Cite

The Permian (293 ± 2 Ma) Sebago Pluton is a homogeneous, two-mica granite situated in the Oxford pegmatite field, southwestern Maine. Surrounding the pluton is an area designated as the Sebago Migmatite Domain (SMD) dominated by metapelitic migmatites and diatexites with subordinate intrusions of heterogeneous, two-mica and biotite granites, pegmatitic leucogranites and granitic pegmatites. The Sebago Pluton plus the SMD formerly defined the extent of the Sebago Batholith. Most of the granitic pegmatites and bodies of pegmatitic leucogranites occur either within, or barely outside, the margins of the SMD. The pegmatitic leucogranite facies displays units typical of fertile granites (granites that produce granitic pegmatites) and include: megacrystic graphic K-feldspar, sodic aplite and potassic pegmatite pods hosting rare tourmaline, beryl and columbite-tantalite. Over 100 granitic pegmatite bodies (Sebago Pegmatite Group -SPG) intrude the outer portions of the SMD and neighboring granitoids and metasedimentary rocks. The pegmatite population includes mineralogically simple to complexly zoned pegmatites that are characterized by a LCT-type (Li, Cs and Ta) geochemical signature, extensive replacement of primary zones and gem-bearing miarolitic cavities. Evidence that supports the pegmatitic leucogranites as the likely parent to the SPG includes the close spatial distribution of the pegmatites to the leucogranite bodies, texturally and mineralogically similar units observed within the leucogranite and the neighboring pegmatites plus gradual, yet overlapping, rare-element fractionation from the leucogranites to the associated pegmatites. A few pegmatites (e.g., the Lord Hill pegmatite and amethyst-bearing pegmatites) show NYF tendencies unlike any other pegmatites of the SPG. Differences in fractionation degree, evolution and/or relation to another fertile granite-pegmatite system may be responsible for this apparently anomalous group of pegmatite dikes.

show abstract

Mineralogical and chemical evolution of a rare-element granite-pegmatite system: Harney Peak Granite, Black Hills, South Dakota

Cited by 75 publications

References 25 publications

The granite system near Betliar village (Gemeric Superunit, Western Carpathians): evolution of a composite silicic reservoir

The granite system near Betliar village (Gemeric Superunit, Western Carpathians): evolution of a composite silicic reservoir

The granitic pegmatites of the Fregeneda area (Salamanca, Spain): characteristics and petrogenesis

Mineral chemistry, petrology and geochemistry of the Sebago granite-pegmatite system, southern Maine, USA

Contact Info

Product

Resources

About