About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Journal of Sedimentary Research (SEPM)

Abstract


Journal of Sedimentary Research
Vol. 79 (2009), No. 12. (December), Pages 887-905
Research Articles

Recognizing Tide-Dominated Versus Tide-Influenced Deltas: Middle Devonian Strata of the Baltic Basin

Kati Tanavsuu-Milkeviciene, Piret Plink-Bjorklund

Abstract

This paper examines the differences between tide-dominated and tide-influenced deltas, as well as tide-dominated deltas and tide-dominated estuaries. The deltaic deposits of the Middle Devonian Kernave and Arukula formations were documented in cores and outcrops in the Baltic Basin and interpreted as tide-dominated delta deposits. These tide-dominated deposits consist of three vertically stacked progradational to aggradational packages, 20–40 m thick. Each package consists of two stratigraphic intervals. The lower upward-coarsening interval contains seaward-accreting prodelta to distal tidal-bar and proximal tidal-bar deposits. The upper upward-fining interval consists of tidal-flat deposits and minor tidal gully, distributary-channel, supratidal muds, and paleosol deposits. The overall character of these delta deposits indicates a subaqueous delta with no river-dominated delta-plain. Comparison of these successions with modern and ancient tide-dominated and tide-influenced deltas suggests that tide-dominated deltaic deposits tend to form in conditions of relative sea-level rise succeeding transgressions, when tidal currents are strong enough to redeposit most river-derived sediments. Tide-dominated deltas form subaqueous deltas, where the bulk of the deposits are tidally reworked. In contrast, tide-influenced deltas contain tidal indicators in delta-front and lower-delta-plain deposits, whereas the upper delta plain is river-dominated. Our data suggest that tide-dominated deltas may change into tide-influenced deltas during delta evolution when they prograde to the mouth of the restricted or funnel-shaped bay, given the rate of fluvial sediment supply exceeds the rate of accommodation increase.


Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24