Seismic interpretation, volcanic, jan mayen

What is it about?

Magmatic activity during the Cenozoic break-up and the opening of the Norwegian-Greenland Sea is preserved in the Jan Mayen Microcontinent. As the emplacements of magmatic rocks on continental margins have implications for both petroleum and mineral exploration. This work is aimed at interpreting evidence of magmatic activity from seismic reflection data and how it influences the geodynamic evolution of the study area. Igneous rocks are interpreted as positive, high amplitude reflections which are also characterized by complex geometries, abrupt terminations in adjacent sediments, and local transgression across stratigraphy levels. In the study area, they are acoustically hard and are either concordant or discordant to sedimentary bedding. The two major seismic facies interpreted in the study area are a) irregular, bedding discordant, intrusive rock, i.e., dikes, saucer-shaped, and bowl-shaped intrusions and b) horizontal, layered, and bedding parallel positive reflections e.g., pillow basalts and tabular sills. The Jan Mayen microcontinent is delimited by these igneous rocks into a western margin rich in extrusive rocks and an eastern region characterized by intrusive igneous rocks. Volcanic sills in the study area can be mapped independently on seismic profiles. They are often associated with post-depositional deformation of the Paleocene rocks. Individual sills exhibit complex fragmentation and are found in close proximity of faults. Base on their interaction with volcanic sills, faults in the study area can be grouped as deep-seated and hard-linked faults, intermediate and shallow faults. The important piece of information from this work is that magmatic intrusions influenced configuration of faults and are sued as the major control on structural reactivation in the study area. The volcanic rocks in Jan Mayen microcontinent were emplaced in Early Eocene during the opening of the southern Greenland Sea. A second phase of volcanic emplacement is related to re-configuration of plate orientation and motion in Oligocene times

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