Chemical profiles of composite intrusions of the Independence dike swarm in eastern California

The 148 Ma Independence dike swarm located in eastern California consists of composite dikes. The multiple intrusions contained within a single dike, known as dikelets, differ in major and trace element concentrations. In syntaxial dikes, where younger dikelets intrude older dikelets down the middle, there is a symmetrical chemical profile displayed across the width of the dike. This confirms that the mode of intrusion is syntaxial since dikelets of the same intrusion event have the same major and trace element concentrations. The multiple intrusion events syntaxial dikes experience causes preexisting dikelets and rock to experience high temperatures during intrusion. Whereas it was expected that the fabric of the outermost dikelet would realign subparallel to the heat flow direction due to cycles in temperature, the grains had no preferred orientation. This could be because there was never any strong perpendicular to dike margin orientation of the grains due to the limited number of thermal cycles (two). Alternatively, textures developed during thermal cycling may have been overprinted during the emplacement of Cretaceous plutons and growth of greenschist facies mineral assemblages in the dikes. Understanding the details of the geochemistry and texture can help construct models on the how the swarm was emplaced.Bachelor of Scienc