The mechanism of intrusion of the Inyo Dike, Long Valley Caldera, California

We analyze the intrusion of the 11-km-long Inyo Dike at the margins of Long Valley caldera, E California. The dike trends N07^oW and is divided into at least 3 segments which are rotated by as much as 25^o with respect to the main trend. The dike seems affected primarily by the regional stress field of right-lateral shear of the western US and by the local thermal conditions of the crust; the dike seems unaffected by the preexisting caldera margins and Sierra-Nevada frontal fault system. We demonstrate that depth variations of tectonic stresses may have a profound effect on the segmentation and rotation of dikes, both at Long Valley and in other areas of high heat flow. -from Authors