Abstract: Abstract For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present or as resulting from better preservation of the younger part of the geologic record. The study of the rocks themselves led to similarly opposing conclusions. The observed secular (= age) variations in relative proportions of lithologic types and in chemistry of sedimentary rocks were mostly given an evolutionary interpretation. An opposing, uniformitarian approach was proposed by Garrels and Mackenzie. For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends. This chapter attempts to show that recycling and evolution are not opposing but complementary concepts. It will concentrate on the lithologic and chemical attributes of sediments but will not deal with the evolution of sedimentary mineral deposits and of life, both well amenable to the outlined conceptual treatment.
Publication Year: 1971
Publication Date: 1971-01-01
Language: en
Type: book
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Cited By Count: 1534
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