Figure 10
From: Earthquake faulting in subduction zones: insights from fault rocks in accretionary prisms
Microstructures of pseudotachylytes. (a-e) Pseudotachylytes from the Shimanto accretionary complex. (f) Pseudotachylyte from the Kodiak accretionary complex (modified from Meneghini et al. 2010). (a) Back-scattered electron image of pseudotachylyte showing fragments in a glassy matrix resulting from rapid cooling of the frictional melt. Albite grains (Ab) with irregular and embayed margins are present in the homogeneous matrix. (b) Vesicles and idiomorphic acicular microlites of muscovite in the matrix. Location of the image is shown in (a). (c) Back-scattered electron image of pseudotachylyte showing an embayed K-feldspar grain (Kf) in the homogeneous matrix. (d) Enlarged view of the embayed K-feldspar grain (Kf), suggesting marginal melting. Vesicles are visible in the matrix. Location of the image is shown in (c). (e) TEM image of pseudotachylyte showing idiomorphic acicular microlites of mullite in a homogeneous, glassy matrix. (f) Back-scattered electron image of pseudotachylyte showing tabular zoned microlites of plagioclase.