The Chukchi region : Arctic ocean : tectonic and sedimentary evolution The Arctic Ocean is an area of increasing interest for research. Variations in the sensitive polar ecosystem influence the environment of the global Earth system and climate change. Therefore reviews of modern Arctic Ocean system thereby provide the basis to interpret the Arctic Ocean evolution through its past. However the evolution of the Arctic Ocean especially the Amerasian Basin remains controversial and multiple oceanic rift models still exist. During the ARK XXIII 3 expedition in the summer of 2008 the Alfred Wegener Institute could acquire the first seismic data set consisting of seismic reflection lines as well as wide angle reflection and refraction data in the northern Chukchi region and on the southern Mendeleev Ridge. In addition further data sets (logging information additional seismic lines gravity data) were available and used within this thesis. Summarising the results we could date six sediment horizons in the research area using the age control from the exploration wells. Furthermore with the interpretation of the tectonic elements the ages of evolution of the northern Chukchi region and the southern Mendeleev Ridge were derived.