Basin architecture and thermal maturation in the strike‐slip Deer Lake Basin, Carboniferous of Newfoundland

• DOI: 10.1111/j.1365-2117.1988.tb00007.x
• Publication Date: 2010-09-13T14:17:12Z
• Authors: RICHARD S. Hyde; HUGH G. Miller; RICHARD N. Hiscott; JAMES A. Wright
• Keywords: Pull apart basin; Trough (economics); Basement; Viséan; Thermal subsidence; Monocline

Abstract The Deer Lake Basin is an entirely non‐marine basin associated with the Cabot fault zone. Structural and stratigraphic evidence strongly suggest dextral strike‐slip movements along zone during Tournaisian‐Visean time. Two elongated, end‐on structural blocks (probable positive flower structures) contain fold axes second‐order faults oriented obliquely to traces bounding blocks, in a manner implying movements. In one part of basin, thickness long homoclinal section later basin‐fill sediment (Deer Group) greatly exceeds suggested depth basement based on gravity measurements, situation common basins. Formations representing fill can be arranged into megasequences (from oldest youngest: Anguille Group, Wetstone Point Wigwam Brook Formations, Howley Formation) corresponding lateral growth stages basin. Gravity, magnetic, seismic data show that depths either side structures are comparable, so youngest strata (Howley not underlain by earlier fill. These geophysical data, therefore, corroborate geological conclusion onlapping relations. participation Carboniferous faulting location subsurface extension Taylors Fault western Basin. Thermal maturation Groups, as measured vitrinite reflectance, clay mineral assemblages, illite crystallinity, Rock‐Eval pyrolysis, indicate much higher level for than Group. Palaeotemperatures Groups estimated around 200 100 o C, respectively, suggesting Group rocks overmature whereas within oil‐generating window. Onlapping relations areally homogeneous time/temperature effects, however, have created which Formation similar levels.