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Ancient Carbonate Tidalites
Yaghoob Lasemi , Davood Jahani ,
Hadi Amin-Rasouli , and Zakaria Lasemi
Abstract
Carbonate tidalites are sediments deposited in supratidal, intertidal and the
adjacent shallow subtidal environments by tidal, biogenic, chemical and diage-
netic processes and are among the most common deposits in ancient carbonate
platform successions. This chapter illustrates sedimentary facies, environments of
deposition, and stratigraphy of carbonate tidalites and describes a few analogs
from ancient deposits that commonly are encountered in the geological record.
Ancient carbonate tidalites consist of a variety of constituents and diagnostic
features formed during deposition and early diagenesis in different environments
of a tidal system. Peritidal facies are arranged into meter-scale, commonly
shallowing-upward succession of subtidal- to tidal fl at facies known as parase-
quence, and may constitute the bulk of the transgressive and highstand packages
of a depositional sequence. The geological record of ancient carbonate tidalites
indicates deposition in the proximal areas of a tropical sea, particularly during
global relative sea level highstands, in carbonate platforms and environments that
have recurred many times since the Paleoproterozoic.
21.1
Introduction
Tidalites are sediments deposited by tidal currents
and are characterized by a distinct combination of sedi-
mentary structures, textures, lithologies, and vertical
successions refl ecting various phases of tidal sediment
transport in carbonate and siliciclastic tidal fl at and
shallow subtidal environments (Klein 1971, 1998 ) .
The term tidalites is somewhat synonymous with
peritidal sediments, sediments formed near the tidal
zone (Wright 1984 ; Flügel 2010 ; Pratt 2010 ) , which
 
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