Page 57 - Petroleum Geology

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c-

2-Y

2-W

Fig. 2-9. Cumulative isopach maps are drawn from these intervals. They reveal a steepening
of the anticline with time. Cross-sections of these maps can also be drawn.

their growth by the greater ultimate compaction of the thicker compactible
units on the flanks. Compaction will also tend to be greater on the flanks be-
cause of the greater sedimentary load. So isopach maps may tend to over-
estimate the growth of the anticline as a whole. This growth is perhaps better
indicated by the relatively incompactible units.
Growth synclines are analogous, but they are not normal drilling targets, so
little is known of them. They are seen in seismic record sections. Growth
monoclines are the essence of a sedimentary basin.
Growth anticlines occur, perhaps, even more widely than growth faults,
but this would not be surprising because they are just variations in the accu-
mulation history of a basin. They occur extensively in the Gulf Coast province
and most of the larger basins of North America; in Venezuela and other areas
of South America; in Europe; in Nigeria; in the Middle East and Russia; in