Principles of Mélanges and Their Bearing on the Franciscan-Knoxville Paradox

Research Article| August 01, 1968 Principles of Mélanges and Their Bearing on the Franciscan-Knoxville Paradox K. JINGHWA HSÜ K. JINGHWA HSÜ Swiss Federal Institute of Technology, Zurich, Switzerland Search for other works by this author on: GSW Google Scholar GSA Bulletin (1968) 79 (8): 1063–1074. https://doi.org/10.1130/0016-7606(1968)791063:POMATB2.0.CO;2 Article history received: 28 Aug 1967 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation K. JINGHWA HSÜ; Principles of Mélanges and Their Bearing on the Franciscan-Knoxville Paradox. GSA Bulletin 1968;; 79 (8): 1063–1074. doi: https://doi.org/10.1130/0016-7606(1968)791063:POMATB2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Mélanges are defined as mappable bodies of deformed rocks characterized by the inclusion of native and exotic blocks, which may range up to several miles long, in a pervasively sheared, commonly pelitic matrix. Fragmentation and mixing of mélanges result from tectonic deformation under an overburden pressure.Mélanges are not rock-stratigraphic units. Structural and stratigraphic interpretations of mélange geology cannot be based upon presumptions of superposed and lateral stratal continuity. Assignment of an age of deposition to a mélange on the basis of fossil occurrences alone can be incorrect. The interpretation that a formation and a partly coeval mélange must be separated by an overthrust contact has also been proved invalid for certain instances. These considerations led to a formulation of five rules of mélanges.The confusion and controversy about the stratigraphic and structural relations between the Franciscan rocks and the Knoxville Formation of the California Coast Ranges have been traced to the fact that the former have been interpreted, and are still being interpreted by some, as a rock-stratigraphic unit. Recognition that those rocks are mélanges and application of the five mélange rules have helped resolve the apparently contradictory stratigraphic and structural relations known as the Franciscan-Knoxville paradox.A large body of mélanges can be subdivided into several tectono-stratigraphic units, based upon the different natures and origins of the mélange blocks and the matrix. Mapping of such mélange units may reveal tectonic superpositions within an apparently chaotic mass. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.