Page 48 - Petroleum Geology

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Fig. 2-2. Diagrammatic cross-section through growth fault with “roll-over” anticline and
antithetic fault.

that they are more common there than elsewhere. They occur in Europe in
the North Sea (Woodland, 1975), in the Vienna basin (Janoschek, 1958), in
the Po Basin of Italy (Rocco and Jaboli, 1958); in Nigeria in the Niger Delta
(Short and Stauble, 1967), in Bengal they have been detected on seismic re-
cords (Sengupta, 1966). Further east, growth faults have been recognized
extensively in north-west Borneo, both on the surface and in the subsurface,
in sedimentary rocks of Late Cretaceous and Tertiary ages (Liechti et al.,
1960). They also occur in and off Western Australia and the southern margin
of Australia (Hosemann, 1971; James and Evans, 1971; Cope, 1972) in rocks of
mainly Mesozoic ages. In South America, they occur in the Eastern Venezuela
basin (Hedberg et al., 1947; Renz et al., 1958). This list is not exhaustive,
but merely a geographic sampling. We shall examine some of these and other
areas in context later in the book. Growth faults are also associated with
growth anticlines, and these occur as widely as growth faults.
In the Los Angeles basin, post-Cretaceous growth faults have been inter-
preted as reverse faults (McCulloh, 1960; Shelton, 1968), and here the up-
thrown blocks were sometimes eroded while the downthrown blocks accu-
mulated sediment. By extension of these concepts, the San Andreas and as-
sociated faults of California, and the Alpine fault of New Zealand, are growth
transcurrent faults that have affected sedimentation and sediment accumula-
tion (and are still affecting them). However, a transcurrent fault with signif-
icant lateral displacement, while clearly having a potential to influence sedi-
mentation and sediment accumulation over a considerable span of time, is a
phenomenon that is peripheral to this discussion.