Beyer, B.J., 1980, Petrology and geochemistry of ophiolite fragments in a tectonic mélange, Kodiak Islands, Alaska: University of California, Santa Cruz, Ph.D. dissertation, 227 p., illust.
The results of a study of five small ultramafic and bodies in the Kodiak Islands, part of a belt of such rocks tectonically included within the Crestaceous Uyak Complex and correlative rocks of southern Alaska are presented. A pivotal aspect of this project was to determine whether these isolated fragments of a presumed ophiolite sequence might be shown to be related to each other in the absence of such definitive field evidence as is commonly found in continuous ophiolite sequences. Based on the strong similarities of their constituent rock types, the blocks of the Kodiak dismembered ophiolite were probably formed in the same or similar environments. Four of the five bodies contain nearly identical layered clinopyroxenites and dunites; two of these bodies also contain identical layered gabbronorites. Ferrogabbro, quartz gabbro, tonalite, and basaltic dikes are the major constituents of only one ophiolite fragment, but minor feldspathic wehrites occur in both this fragment and one other.
Theses and Dissertations