Archer, Allen W., Erik P. Kvale, and Hollis R. Johnson, 1990. Discussion on Late Precambrian tidal rhythmites in South Australia and the history of the Earth's rotation: Journal of the Geological Society of London, 146:401-407.

Introduction to Discussion:In a recent paper Williams (1989) claims that tidally deposited, rhythmically laminated siltstones from the Precambrian (650 Ma) of Australia (Elatina Formation) can be used to extract specific values for the parameters of the ancient Earth-Moon-Sun system. However, analysis of modern tidal data indicates that the basic assumptions regarding Precambrian tidal processes may have been oversimplified, with consequent understatement of the uncertainties involved.

Brown, Mark A., Allen W. Archer, and Erik P. Kvale, 1990. Neap-spring tidal cyclicity in laminated carbonate channel-fill deposits and its implications: Salem Limestone (Mississippian), south-central Indiana, U.S.A: Journal of Sedimentary Petrology, 60:152-159.

AbstractLimestone beds containing rhythmic parallel laminations occur within a channel-fill sequence exposed locally in the Salem Limestone (Mississippian) of Indiana. The laminations consist of carbonate grains and micrite in layers up to 2 mm thick capped by thin (0.1-0.3 mm) drapes of organic matter. Each couplet was generated by mixed or semidiurnal tidal events, during which carbonate sediment was mobilized and deposited by the dominant tide and organic matter settled from suspension during slackwater conditions. Laminae thicken and thin systematically in a vertical sequence as a result of neap-spring tidal current fluctuations that occur during a lunar month.

Laminations are well preserved in certain beds ranging from 20 to 30 cm thick through much of the channel-fill sequence. Other beds are extensively bioturbated and contain only a partial record of the laminations. The sequence of bioturbated and unbioturbated units defines a rhythmic pattern, suggesting periods of seasonal environmental restriction that precluded burrowing organisms. Estimation of sedimentation rates based on the neap-spring tidal cycles indicates that deposition within the channel occurred very rapidly (averaging 35 cm/year), a rate four orders of magnitude faster than calculated long-term depositional rates.

Kvale, Erik P., and Allen W. Archer, 1990. Tidal deposits associated with low- sulfur coals, Brazil Formation (Lower Pennsylvanian), Indiana: Journal of Sedimentary Petrology, 60:563-574.

Abstract:The interval between the Lower and Upper Block Coal Members of the Brazil Formation (Lower Pennsylvanian, Indiana) records a transgression of brackish water tidal deposits over a coastal domed(?)-peat field, followed by a regression, and then re-establishment of the peat-forming environment. Within the study area, the interval averages 8 m in thickness and consists of a basal sequence of laminated mudstone that coarsens upwards to a thinly interlayered sandstone and mudstone (lenticular, wavy, and flaser bedding). This is capped by an upward-fining sequence into a rooted mudstone.

Sedimentation rates can be estimated by detailed thickness measurements of vertically stacked mudstone laminae and sandstone layers that thicken and thin rhythmically. The rhythmic thickness variation can be related to neap-spring tidal-current cyclicity and indicates that sedimentation varied from 1 cm/yr to 1 m/yr. Locally, as much as 8 m of accommodation space for the sediments appears to have been generated and mostly filled in a matter of decades to a few centuries. Such rapid rates of filling indicate the possibility that the accommodation space was generated by compaction of the transgressed peat and mud-rich sediments.