Seismic Exploration in The Kylylahti Cu-Au-Zn Mining Area: Comparison of Time and Depth Imaging Approaches

Summary High-resolution seismic reflection profiles were acquired in the Kylylahti polymetallic mine area in the Outokumpu region, Finland, in the framework of the COGITO-MIN project. Acquisition was performed along two segmentally straight lines using both vibroseis and dynamite sources. We present three different versions of the data imaging, one utilizing post-stack time migration, second pre-stack time migration and third Fresnel Volume pre-stack depth migration algorithms. Seismic images reveal steep reflectors at less than 500 m depth that correlate with the black schist intercalations in the mica schist as well as strong reflectors at 5–8 km depth attributed to mafic dykes on top of Archean basement rocks. The rock assemblage hosting the mineralisation is imaged as prominent but discontinuous reflectivity due to its complex internal structure caused by folding and faulting.