Magmatic Layering Granites

The most characteristic feature of mingling in high strain in contrast with low strain zones is the development of layering very similar in nature to tectonic solid state sheared gneisses.

Magmatic layering granites. Layered granites are rare and occur in association with volumetrically dominant non layered rocks having similar composition. Unidirectional solidification texture ust a type granite magmatic layering aplite pegmatite yttrium garnet train texture. This is llanduno. Instabilities within the magmatic layer.

Observations in the s type granites s l of the wilson s promontory batholith demonstrate that one type of schlieren in granitic rocks represent accumulations of mainly mafic magmatic minerals with internal layering formed through pulsed magma flow. Magmatic layering in granites prompted by a recent discussion on the granite research list 1 one that was interesting for a change here are a few photos of magmatic layering in the panafrican peninsula pluton at llanduno on the atlantic side of the peninsula south of cape town. Relationships between enclaves and schlieren layering in granites. Dark enclave with tip streaming in velay leucogranite le peyral ardèche french massif central.

The podlesí granite stock czech republic is a fractionated peraluminous f li and p rich and sn w nb ta bearing rare metal granite system. Llanduno more photos here. Scale bar 2 5 cm. Some of the rhyolite dykes contain topaz as.

Introduction rarely occurred magmatic structure unidirectional solidification textures ust are known as a specific type of the magmatic layering. This section depicts magmatic layering within an e w trending magmatic shear zone in the southern part of the corsica batholith. Some beautiful comb layering unidirectional structures are also well developed. Loss of interstitial magmatic liquid played at most a minor role in shaping the preserved compositions of the schlieren.

Its magmatic evolution involved processes typical of intrusions related to porphyry type deposits explosive breccia comb layers rare metal granites stockscheider and rare metal pegmatites extreme f p li enrichment nb ta sn minerals. The magmatic origin of accessory cassiterite in the topaz bearing granite average 80 ppm sn is indicated by mode of occurrence and chemical composition of cassiterite. Layering here is beautifully developed and locally magmatic deformation deforms the original layering in systematic ways. Rhythmic magmatic layering in granites is an intriguing feature that has been reported from plutons with contrasting chemical compositions from a wide range of tectonic settings.

This non genetic term describes the. The nb 2 o 5 ta 2 o 5 content of cassiterite is 4 8 8 7 wt in granite 2 3 3 in pegmatite and 0 0 0 6 in greisen.