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JOURNAL OF SEDIMENTARY PETROLOGY, VOL. 47, No.4 (1977), 1542-1553 SEDIMENTARY FILLINGS OF ANCIENT DEEP-SEA CHANNELS: TWO EXAMPLES FROM NORTHERN APENNINES (ITALY) I. PETER MARTINI1 and MARIO SAGRI2 1Department of Land Resource Science, University of Guelph, Guelph,
Ontario, Canada กก  To try and
determine the significance of thinning-upward sequences, two turbidite
sections in the Monte Modino Formation (Oligocene, Northern Apennines,
Italy) were studied. The two sections are geographically and
stratigraphically several hundred meters apart. One section, consisting of
a geometrically definable channel cut into an olistrostrome contains
thinning-upward sequences. The second section comprises thinning-upward
cycles that alternate with portions of the sequence with no regular
changes in bed thickness. Comparison of these Oligocene rocks with modern
deep- sea deposits and subaerial fans suggests that thinning-upward
sequences may form in channels and valleys which need not necessarily be
erosional ones. Thus, these sequences may indicate shifts of thalweg of
flows as a response to partial plugging of depressions.
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