Seismic datafrom the East Greenlandshelfshow thatthe northern part ofthe shelf, northof75 8 N, can be subdivided into five, roughly northeast-trending, major tectonic elements. From west to east theyare: the KoldeweyPlatform,the Danmarkshavn Basin,the Danmarkshavn Ridge, the ThetisBasinandthe MarginalHigh. Asixthtectonic element,the Shannon High, hasbeendefined inthe southern part ofthisarea.The offshoreareas between72 8 30 0 Nand75 8 Naredominated byTertiary plateaubasalts,which obscurethe acoustic signals from the deepers edimentary succession. Seismic dataf rom the area northof75 8 Ni ndicatethe presence ofafairly completesuccession of?Devoniant oNeogenea ge, exceedingthe recorded interval( 8sec TWT -13 km) in thickness int he deeperp arts ofthe Danmarkshavn Basin. The succession hasbeens ubdivided into 15seismic mega-sequences. Inabsence ofwell control,theyhavebeendated bycomparisontothe onshoresuccessions of East Greenlandandeastern NorthGreenland, andthe offshoresuccessions inthe southern Barents Sea andon the mid-Norwegianshelf.The UpperPalaeozoic succession isbroadly similartothatofthe southern Barents Sea, i.e. marine-dominated,withthick UpperCarboniferous-LowerPermianhalited eposits int he northern Danmarkshavn Basin. The Mesozoic succession seems to show greaters imilaritiest ot he onshoreb asins of East Greenland: riftingstarted duringthe mid-Jurassic andpeaked nearthe Jurassic-Cretaceous boundary. The post-volcanic succession reflects deposition on apassivemargins ubjected to temporary upliftduringthe early Mioceneandthe latest Mioceneto earliest Pliocene.

Sequence stratigraphic interpretation of paralic successions is complicated by the complex interfingering of marine and continental strata. The successions may also include terrestrial extensions of marine parasequences and completely independent lacustrine parasequence analogues. Failure in recognizing the possible interbeddding of these two independent parasequence types may lead to construction of sequence stratigraphic schemes based on incompatible data sets. We have studied a Lower Jurassic paralic section from the Baltic island of Bornholm, situated in the Tornquist Zone, which demarcates the transition from the stable Precambrian Baltic Shield to the subsiding Danish Basin and Danish‐Polish Trough. The Hettangian‐Sinemurian Sose Bugt Member (Rønne Formation) of Bornholm includes lacustrine, fluvial and restricted marine, estuarine deposits reflecting the basin‐margin position. Biostatigraphic resolution is poor and a sequence stratigraphic interpretation of the paralic succession is far from straightforward. A multidisciplinary approach including facies analysis, recognition and lateral trading of key surfaces, palynostratigraphy, palynofacies, coal petrography, palaeopedology, clay mineralogy and source rock geochemistry is applied in order to obtain a high degree of precision in the interpretation of the paralic facies. In this way four sequences are recognized in the overall backstepping lacustrine to estuarine succession. Marine and marginal marine parasequences are distinguished from their purely lacustrine analogues, and an internally consistent sequence stratigraphic scheme is proposed. This is compared and tentatively correlated with fossiliferous marine sediments in the Danish Basin and with published eustatic cycle charts.

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Detailed shallow seismic investigations of the eastern R0nne Graben, offshore Bomholm have resulted in the recognition of characteristic seismic facies which are subdivided into seismostratigraphic units. The seismostratigraphic units are correlated with known lithostratigraphic units on Bomholm, thus permitting detailed geological mapping along the eastern margin of the Rønne Graben. In contrast to the sequence on Bomholm, it appears that there was continuous sedimentation from the R0nne Formation (Lower Jurassic) to the Rabekke Formation (Lower Cretaceous), while the Robbedale and Jydegard Formations (Lower Cretaceous) are absent in the R0nne Graben. In the area mapped in detail the youngest Pre-Quaternary sediments are the Arnager Greensand, the Amager Limestone and the Bavnodde Greensand Formations (Upper Cretaceous). All the Mesozoic deposits were affected by transpressional tectonic activity during the Upper Cretace­ous - Lower Tertiary. The structural relationships show a characteristic pattern consisting of the main fault on the eastern side of the Rønne Graben and a system of en echelon reverse faults. This pattern probably formed as a result of northeast-southwest wrench movements in a compressional dextral strike slip system.