Field characteristics of laterally emplaced dikes: Anatomy of an exhumed Miocene dike swarm in Reydarfjördur, eastern Iceland |
| |
Authors: | Johann Helgason Marcos Zentilli |
| |
Abstract: | Many dikes of the Tertiary Breiddalur dike swarm in Reydarfjördur have a great lateral extent but are vertically (upward and/or downward) discontinuous. Field relationships indicate that they are not the feeders of the lava pile they intrude. Their characteristics can be best interpreted as them constituting the fossil expression of lateral magma emplacement analogous to that occurring in the actively spreading Krafla volcanic center of the neovolcanic zone. Average dike thickness increases clearly with depth and the thickness versus depth relationship is different from that described for other Tertiary dike swarms in eastern Iceland. It is suggested that dikes represent the extent of finite spreading which at higher levels in the crust is expressed by fissures and other extensional structures. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |