Importance of
Gravity-Driven Compressional Tectonics in Northern
Offshore and Deep-Offshore
Philippe, Yann, David
Wittoesch, Gwenael Guerin, Total E&P USA, Inc,
The offshore and deep-offshore GoM is
characterized by the massive allochthonous Sigsbee salt canopy that was sourced from autochthonous
salt by vertical or oblique salt feeders. This canopy is now buried below Late
Miocene or younger mini-basins. Salt feeders are generally considered as
Mesozoic to Early Miocene passive diapirs squeezed by
contraction in the Middle-Late Miocene.
Our seismic interpretations suggest that salt feeders originated
as salt-cored contractional anticlines rather than
passive diapirs. Seismic and well data also reveal
the presence of condensed Mesozoic-Middle Miocene slabs above the Sigsbee canopy. These slabs represent autochthonous
Mesozoic-Paleogene anticlines or plateaus that were
incorporated into the canopy in the form of allochthonous
rafts. These initial anticlines and plateaus were part of a broad contractional domain which included the
As it covers the
whole deep-water GoM and parts of the Louisiana-Texas
shelf, the Mesozoic to Miocene gravity-driven contractional
domain is thus much wider than previously believed. This alternate
interpretation helps to clarify the tectono-sedimentary
evolution in the subsalt interval prior to, during
and after Sigsbee canopy development.