Relative sea-level variations in the Amerasia Basin since the Lower Cretaceous

• Main Authors: Hegewald, Anne, Jokat, Wilfried
• Format: Conference Object
• Language: unknown
• Published: 2010
• Subjects: Arctic; Arctic Ocean; Chukchi Shelf; Amerasia Basin; East Siberian Shelf; Chukchi; Alaska
• Online Access: https://epic.awi.de/id/eprint/22982/; https://hdl.handle.net/10013/epic.36290

In 2008, the Alfred Wegener Institute (AWI) of Germany, using the RV Polarstern, collected multi-channel seismic reflection data in the eastern Arctic Ocean (73-78°N and 170°E-170°W), namely across the East Siberian Shelf, the Chukchi Plateau and the southern part of the Mendeleev Ridge. For the seismic data acquisition an airgun array with up to six airguns (48 ltr. total volume fired at 200 bar) and a 3000 m long streamer with 240 active channels were used.One of the profiles, collected from the Chukchi Shelf towards the north into deep water, shows the paleo-shelf break structures over 250 km length as prograding, retrograding and aggrading sequences with a total thickness of 3500 m. To receive the ages of these sequences, five exploration wells near the coast of Alaska were used. An existing network of 194 seismic reflection lines from the United States Geological Service (USGS), collected between 1977 and 1993, from the Norwegian company TGS-NOPEC (2006), and the American HOTRAX Expedition (2005) were used to correlate the well logging information into the AWI data. With the help of this network, it was possible to correlate tentatively four prominent horizons with ages between the Paleocene and Lower Cretaceous into the new data. The interpreted sequence boundaries in the seismic reflection profile were used to determine its chronostratigraphic significance, and concluded from that, the relative sea-level changes. Finally, in this presentation the Arctic Ocean sea-level changes will be compared with the global sea-level curve.