P-Wave Modelling of the ContinentOcean Transition of the East Greenland Volcanic Margin North of Jan Mayen Fracture Zone

• Main Authors: Schroeder, Michael, Jokat, Wilfried
• Format: Conference Object
• Language: unknown
• Published: 2005
• Subjects: Greenland; Jan Mayen; Jan Mayen Fracture Zone; Kong Oscar Fjord; Lofoten; Norway; Shannon Island; Vøring Plateau; East Greenland; Kong Oscar fjord; Shannon
• Online Access: https://epic.awi.de/id/eprint/13112/; https://epic.awi.de/id/eprint/13112/1/Sch2005am.pdf; https://hdl.handle.net/10013/epic.23504; https://hdl.handle.net/10013/epic.23504.d001

Between the Jan Mayen and the Greenland Senya Fracture Zone the continentocean transition off East Greenland is less well known in contrast to the well explored and studied volcanic rifted margin off Norway. The geophysical and geological data at the Norwegian Vøring and Lofoten margin reveal important vertical and lateral variations in crustal structure and composition. The deeper structure of the East Greenland margin conjugate to the Vøring Plateau is therefore of special interest.One of the main targets is to estimate the amount of magmatic material which intruded and/or underplated the crust compared to the Vøring Plateau, which is a huge magmatic complex. Existing gravity and magnetic data off East Greenland do not support the presence of a feature like the Vøring Marginal High yet. Although MCS and potential field data exist along the East Greenland margin, the data density is insufficient to image lateral variations in the deeper structure. One striking feature of the East Greenland margin, which most likely was connected with the initial tertiary break-up, is marked by a pronounced negative magnetic anomaly. It runs parallel to the coast for more than 400 km between Kong Oscar Fjord at 72° N and south of Shannon Island at 75° N. Its shallow and deeper structure was not known so far.In 2003, new seismic refraction data were acquired on four 300 450 km long profiles by RV Polarstern to investigate the deep structure of the East Greenland continental margin. In addition, ship borne gravity data as well as aeromagnetic data, which cover the area over the two southern seismic refraction profiles (AWI-20030400 and AWI-20030500), were gathered to provide constraints on the extent of the magnetic anomaly.The new acquired aeromagnetic data yield high frequent variations within the pronounced negative anomaly and eastward. The wavelengths of the variations are approx. 5 km. The p-wave model of the seismic refraction profile AWI-20030400 shows a striking correlation with the potential field data, e.g. a basement ...