Seismic Volcanostratigraphy: The Key to Resolving the Jan Mayen Microcontinent and Iceland Plateau Rift Evolution

Volcanostratigraphic and igneous province mapping of the Jan Mayen microcontinent (JMMC) and Iceland Plateau Rift (IPR) region have provided new insight into the development of rift systems during breakup processes. The microcontinent's formation involved two breakup events associated with seven distinct tectono-magmatic phases (similar to 63-21 Ma), resulting in a fan-shaped JMMC-IPR igneous domain. Primary structural trends and anomalous magmatic activity guided initial opening (similar to 63-56 Ma) along a SE-NW trend from the European margin and along a WNW-ESE trend from East Greenland. The eastern margin of the microcontinent formed during the first breakup (similar to 55-53 Ma), with voluminous subaerial volcanism and emplacement of multiple sets of SSW-NNE-aligned seaward-dipping reflector sequences. The more gradual, second breakup (similar to 52-23 Ma) consisted of four northwestward migrating IPR (I-IV) rift zones along the microcontinent's southern and western margins. IPR I and II (similar to 52-36 Ma) migrated obliquely into East Greenland, interlinked via segments of the Iceland-Faroe Fracture Zone, in overlapping sub-aerial and sub-surface igneous formations. IPR III and IV (similar to 35-23 Ma) formed a wide igneous domain south and west of the microcontinent, accompanied by uplift, regional tilting, and erosion as the area moved closer to the Iceland hotspot. The proto-Kolbeinsey Ridge formed at similar to 22-21 Ma and connected to the Reykjanes Ridge via the Northwest Iceland Rift Zone, near the center of the hotspot. Eastward rift transfers, toward the proto-Iceland hotspot, commenced at similar to 15 Ma, marking the initiation of segmented rift zones comparable to present-day Iceland.

Automated summary

Volcanostratigraphic and igneous province mapping of the Jan Mayen microcontinent and Iceland Plateau Rift region provide new insights into the development of rift systems during breakup processes, revealing two breakup events, seven distinct tectono-magmatic phases, and four rift zones.