thumbnail

Blueschist-facies metamorphism related to regional thrust faulting

Tectonophysics

By:
, ,

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time

Abstract

Rocks of the blueschist (glaucophane schist) facies occur throughout the world in narrow tectonic belts associated with ultramafic rocks. In the Coast Range province of California, blueschist rocks are devloped in the eugeosynclinal Franciscan Formation of Late Mesozoic age. The blueschist rocks form a narrow belt for more than 800 km along the eastern margin of this province and commonly are separated from rocks of an overlying thrust plate by serpentinite. Increasing metamorphism upward toward the thrust fault is indicated mineralogically by a transition from pumpellyite to lawsonite and texturally by a transition from metagraywacke to schist. The blueschist metamorphism probably occurred during thrusting in a zone of anomalously high water pressure in the lower plate along the sole of the thrust fault. This tectonic mode of origin for blueschist differs from the generally accepted hypothesis involving extreme depth of burial. Other belts of blueschist-facies rocks, including the Sanbagawa belt of Japan, the marginal synclinal belt of New Zealand, and the blueschist-ultramafic belts of Venezuela, Kamchatka, Ural mountains, and New Caledonia have similar geologic relations and might be explained in the same manner. ?? 1969.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Blueschist-facies metamorphism related to regional thrust faulting
Series title:
Tectonophysics
Volume
8
Issue:
3
Year Published:
1969
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
237
Last page:
246
Number of Pages:
10