Blueschist - Wikipedia
Blueschist often has a lepidoblastic, nematoblastic or schistose rock microstructure defined primarily by chlorite, phengitic white mica, glaucophane, and other minerals with an elongate or platy shape.
Blueschist : Compositions, Properties, Formation - Geology Science
Jan 12, 2023 · Mineral Assemblage: Blueschist is characterized by a specific mineral assemblage that reflects its formation under high-pressure, low-temperature conditions. Key minerals include glaucophane (a blue amphibole), lawsonite, jadeite, epidote, and garnet.
Blueschist - ALEX STREKEISEN
Blueschist is a regional metamorphic rock formed under high-pressure (HP) low-temperature (LT) conditions. It is formed in the subduction zone environment with low geothermal gradients (4-14°C km -1 ) and is characterized by the presence of HP/LT index minerals like glaucophane, lawsonite, aragonite, jadeite, and deerite ( Fig.1 ).
Metamorphic Rock Types: Pictures and Descriptions - ThoughtCo
May 10, 2019 · Blueschist is a schist because all traces of original structure in the rock have been wiped out along with the original minerals, and a strongly layered fabric has been imposed. The bluest, most schistose blueschist—like this example—is made from sodium-rich mafic rocks like basalt and gabbro.
Blueschist - Geology 1501 - ECU
Blueschist (subtype of Regional) Metamorphic Grade. High P – Low T. Parent Rock. Basalt and Seafloor sediments. Metamorphic Environment. Along subduction zones at convergent plate boundaries. East Carolina University. Department of Geological Sciences.
Blueschist: A window into high-pressure/low-temperature …
Jul 20, 2020 · Blueschist is a regional metamorphic rock formed under high-pressure (HP) low-temperature (LT) conditions. It is formed in the subduction zone environment with low geothermal gradients (4–14°C km −1), and is characterized by the presence of HP/LT index minerals like glaucophane, lawsonite, aragonite, jadeite, and deerite.
Emergence of blueschists on Earth linked to secular changes in …
Dec 14, 2015 · Blueschists are glaucophane-bearing metabasalts 5, 6 that form at high-pressure–low-temperature (H P –L T) conditions in the Earth, typically along geothermal gradients of 150–400 °C GPa −1.
Blueschist Facies - an overview | ScienceDirect Topics
Beyond depths of ∼15 km the oceanic crust enters into the blueschist facies in which the major hydrous minerals are chlorite, sodium-rich, calcium-poor amphiboles (glaucophane to barroisite), phengite (white mica), lawsonite or zoisite, and paragonite (e.g., Sorensen, 1986).
Blueschist - an overview | ScienceDirect Topics
The blueschist metamorphic facies are characterized by the minerals jadeite, glaucophane, epidote, lawsonite, and garnet. They record metamorphism in the cool high-pressure/low-temperature thermal gradients at less than 7°C/km in subduction zones in the last 1 billion years.
8.8: High-Pressure Rocks and Minerals - Geosciences LibreTexts
Aug 28, 2022 · The blueschist seen below in Figure 8.78 is mostly glaucophane. Other common blueschist minerals include a colorless to green Na-pyroxene called jadeite , green or white lawsonite, and pale aragonite (the high-pressure polymorph of calcite).