A GIS BASED STUDY OF MAFIC DIKE ORIENTATION IN SOUTHEAST UTAH
In this study, minette dikes in the NVF south of Bluff, Utah were investigated to compare with regional data. Twenty-six dike segments were identified in the study area using GIS aerial imagery. Dike orientations range from 349 o to 010 o with an average of 003 o. Previous work documents that fracture sets associated with Comb Ridge have two dominant orientations (N-S and NNE-SSW ), Rio Grande Rift extensional features have ENE-WSW orientations, while magmatic emplacement not related to the previous two mechanisms is more random.
Due to timing constraints, the observed trends documented in NVF dikes in the study area are most consistent with both magmatic factors and Rio Grande Rift extension. The interplay of magmatism and tectonics south of Bluff and the implications for dike emplacement are discussed thoroughly in this report.