K. Hinz, 1983. "Line Bgr 76-11 from Central East Greenland Margin", Seismic Expression of Structural Styles: A Picture and Work Atlas. Volume 1–The Layered Earth, Volume 2–Tectonics Of Extensional Provinces, & Volume 3–Tectonics Of Compressional Provinces, A. W. Bally
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The outstanding feature of the East Greenland continental margin between latitudes 67° and 72°N is a sedimentary wedge up to 5,000 m (16,400 ft) thick which unconformably overlies the top of the acoustic basement (sequence GR-5).
The top of the acoustic basement is marked by a flat to hummocky, continuous unconformity (labeled the top of rift phase or TRP-reflection horizon), often with subacoustic basement reflectors and diffractions beneath. This unconformity is interpreted to represent the end of a rift phase in the Oligocene. The irregular reflection pattern beneath this unconformity and the derived instantaneous velocity of about 4.5 km/sec (2.8 mi/sec) might represent a highly consolidated and faulted succession of Paleogene and even older sediments.
The overlying thick sedimentary wedge has been divided into the four depositional sequences GR-1 to GR-4. Sequence GR-4 is characterized by a subparallel bedding with some high amplitude reflectors and interval velocities which increase from about 2.5 km/sec (1.6 mi/sec) at the outer slope from 4 to 4.5 km/sec (2.5 to 2.8 mi/sec) beneath the present shelf. Sequence GR-4 is interpreted as representing a consolidated, interbedded succession of sandstones and shales of upper Oligocene to upper Miocene age.
The overlying and seaward-thinning sequences GR-3 and GR-2 have a prograding clinoform pattern suggesting strong outbuilding and upbuilding into a subsiding basin. Beneath the lower slope, a feature with a non-coherent pattern occurs within sequence GR-2 which is thought to represent a slumped mass. The uppermost sequence GR-1 is thin and is interpreted as representing mainly glacial and glacial-marine sediments.