BH250-117
Title
BH250-117
Subject
Schist
Description
BH250-117 – Muscovite–Quartz Schist with Boudinage Structures
This specimen is a muscovite–quartz schist in which the quartz crystals are strongly deformed, exhibiting classic boudin-type structures formed by extension and layer-parallel stretching. In thin section, the schistosity is defined by the parallel alignment of muscovite flakes, some of which are preserved as inclusions within the quartz crystals. These internal mica trails record the rock’s progressive deformation history, where earlier fabric was overprinted by later quartz recrystallization and stretching. The texture reflects intense ductile deformation under regional metamorphic conditions.
This specimen is a muscovite–quartz schist in which the quartz crystals are strongly deformed, exhibiting classic boudin-type structures formed by extension and layer-parallel stretching. In thin section, the schistosity is defined by the parallel alignment of muscovite flakes, some of which are preserved as inclusions within the quartz crystals. These internal mica trails record the rock’s progressive deformation history, where earlier fabric was overprinted by later quartz recrystallization and stretching. The texture reflects intense ductile deformation under regional metamorphic conditions.
Coverage
Northfield, Minnesota, USA
Creator
Bereket Haileab
Source
From the rock collection of Bereket Haileab. Sample 117. Housed at Carleton College in Minnesota.
Type
Thin section and hand sample
Relation
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Collection
Citation
Bereket Haileab, “BH250-117,” BH250 Mineralogy Teaching Collection, accessed April 25, 2026, https://bereket-haileab.geology.sites.carleton.edu/items/show/138.