The groundwork for the northeast Atlantic opening was laid during the latest Jurassic to mid-Cenozoic. The period is well-investigated on the Norwegian and UK continental margins at which the tremendous petroleum potential to a large extent resulted from the latest Jurassic to mid-Cenozoic development. Harsh ice conditions have made investigations of the NE Greenlandic margin more difficult. Based on a large 2D seismic dataset tied to cored stratigraphic boreholes, three phases of rifting leading to continental breakup are documented: 1) latest Jurassic to mid-Cretaceous, 2) mid-Cretaceous to Maastrichtian and 3) Maastrichtian to early Eocene. This development is in many ways comparable to offshore Norway. However, Early Cretaceous rifting was more severe offshore NE Greenland compared to elsewhere in the northeastern Atlantic with more than 10 km downfaulting and accumulation of up to 16 km of Lower Cretaceous strata in the Danmarkshavn and Thetis basins. During the mid-Cretaceous, rifting ceased in most of the Danmarkshavn Basin and the inner Thetis Basin but continued in the outer Thetis Basin. This coincides with a shift in rifting taking place in the Barents Sea, offshore central Norway, and onshore NE Greenland.

During the latest Cretaceous, rifting shifted seawards to the outermost NE Greenland margin and the eventual line of continental break-up, again mirroring the development at the central Norwegian margin. Coincident uplift of Greenland resulted in clinoform progradation across the central and southern Danmarkshavn Basin and incursion of Greenland-derived sand to offshore central Norway. The uplift and change in rifting may reflect the initial effects of the Icelandic mantle plume building up underneath Greenland. Shortly thereafter, magmatism commenced along parts of the NE Greenland margin followed by continental break-up. Subsequently, small amounts of compression on the outer margin formed subtle folds and small thrusts during presumably Oligocene to early Miocene times.

东北大西洋开放的基础是在最新的侏罗纪到中新生代期间奠定的。这一时期在挪威和英国大陆边缘得到了很好的研究，那里巨大的石油潜力在很大程度上源于侏罗纪到中新生代的开发。严酷的冰况使得对东北格陵兰边缘的调查更加困难。基于与取芯地层钻孔相关的大型 2D 地震数据集，记录了导致大陆分裂的三个阶段的裂谷：1) 侏罗纪晚期至白垩纪中期，2) 白垩纪中期至马斯特里赫特纪，3) 马斯特里赫特纪至始新世早期。这种发展在很多方面都可以与挪威近海相媲美。然而，与大西洋东北部其他地区相比，格陵兰岛东北部的早白垩世裂谷更严重，在丹马克港和忒提斯盆地的下白垩纪地层断层超过 10 公里，堆积达 16 公里。在白垩纪中期，大部分丹马克港盆地和内塞蒂斯盆地的裂谷作用停止，但外塞蒂斯盆地仍在继续。这恰逢巴伦支海、挪威中部近海和格陵兰岛东北部陆上裂谷发生转变。

在最近的白垩纪，裂谷向海移动到最外的格陵兰东北边缘和大陆分裂的最终线，再次反映了挪威中部边缘的发展。格陵兰岛的同时隆起导致丹麦沙文盆地中部和南部的斜坡进积，以及格陵兰岛的沙子侵入挪威中部近海。裂谷的隆起和变化可能反映了冰岛地幔柱在格陵兰下方积聚的最初影响。此后不久，岩浆作用沿着格陵兰东北部边缘的部分地区开始，随后大陆破裂。随后，在大概渐新世到中新世早期，外缘的少量压缩形成了微妙的褶皱和小的逆冲。