Page 47 - Petroleum Geology

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Fig. 2-1. Diagrammatic cross-section through simple growth fault.

pian) sedimentation so that there is a contrast of facies across the fault, and
Tiddeman clearly recognized its significance. Dron (1900) later recognized a
similar Lower Carboniferous fault in Scotland, involving coal measures. In
the coalfields of western Germany, the existence and interpretation of com-
plicated growth structures became well accepted during the 1920s (Bottcher,
1925, 1927), and these concepts were later extended to oil fields in south-
east Europe by Stutzer (1930, unfortunately in Abstract only). By the late
1940s, growth faults were recognized in several countries, mainly as a result
of coal mining or petroleum development.
Growth faults are important in the Gulf Coast province of North America,
and many of the “down-to-the-basin”* faults there are growth faults. They
are commonly extensive, with a tendency to be curved in plan and to be
generally parallel to the basin margins and the depositional strike. They may
form en echelon. Locally they may be conjugate, forming graben. They are
commonly associated with flexures (“roll-over anticlines” in the jargon) and
with antithetic faults - both on the downthrown side (Fig. 2-2). In section,
growth faults commonly flatten with depth, but may also be sinuous. They
have been reported more commonly in post-Eocene beds in the Gulf Coast
province, but they also affect Mesozoic and Palaeozoic sedimentary rocks.
Much of what we know about growth faults has come from the Gulf
Coast province because of the enormous and sustained drilling effort there,
but emphasis on this province in the literature must not be taken to mean

* This is an ill-conceived but widely used term. They are “down-to-the-basin” in a physiog-
raphic sense, perhaps, but may be anywhere in a sedimentary basin.