Abstract
Abstract An example of sheet-like intrusion emplacement at very shallow crustal levels on Elba Island, Italy, is described. The Eastern Elba Dyke Complex (EEDC) consists of decimetre- to metre-thick sheeted aplites emplaced within intensely folded low-grade metamorphic rocks. Field data indicate that sill and dyke emplacement was controlled by mechanical discontinuities, represented by fractures in the host rocks, and was strongly favoured by magma overpressure. The occurrence of angular fragments of host rocks in the dyke border zones and the branching of sills testify to hydraulic fracturing. Analysis of the spatial distribution and geometry of EEDC sills and dykes provides clues on fluid pressure conditions and the stress state at the time of magma emplacement, as well as on the depth of emplacement. The calculated stress ratio and driving pressure ratio were used to estimate a magma overpressure of 6–54 MPa at the time of emplacement of the EEDC at a depth of about 2 km.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.