cyclothem

cyclothem

[′si·klə‚them]
(geology)
A rock stratigraphic unit associated with unstable shelf of interior basin conditions, in which the sea has repeatedly covered the land.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The sedimentary succession of the middle portion of Cyclothem 14 is illustrated in Figure 3 (after Falcon-Lang 2006).
Each complete unit in the rock succession is known as a cyclothem. Measured from the base of one limestone to the base of the next, each cyclothem represents a few million years of geological time, in which depositional conditions changed from the warm clear-water marine conditions in which the limestones formed, to the more turbid deltaic and lagoonal environments in which the sandstones and shales were deposited.
Consequently, marine and nonmarine beds alternate and interfinger to form a pattern of transgressive and regressive rock deposition, which is commonly referred to as the classic Pennsylvanian cyclothem sequence.
As such, this sequence is part of a cyclothem (Gibling and Bird 1994) in a terrestrial environment of an extensive costal platform (Wightman et al.
Diagenetic Model for Carbonate Rocks in Mid-Continent Pennsylvanian Eustatic Cyclothems. AAPG Bulletin, 66(5), 580-580.
Trace-element behavior and redox facies in core shales of Upper Pennsylvanian Kansas-type cyclothems. Chem.
1 Percentage of clastic rocks in cyclothems of Upper Carboniferous in USCB: CSS--Cracow Sandstone Series; MS--Mudstone Series; USSS--Upper Silesian Sandstone Series; PS--Paralic Series conglomerate sandstone CSS 3 81 MS 27 USSS 2 53 PS 47 Note: Table made from bar graph.
Trace element behavior and redox facies in core shales of Upper Pennsylvanian Kansas-type cyclothems. Chemical Geology, 206, 289-318.
Earlier studies recorded a braided-meandering fluvial depositional system with peat-forming mires in the low-lying marshy floodplains that produced thick succession of sandstone-shale-coal cyclothems within the Barakar Formation [7].
Trace-element behaviour and redox facies in core shales of Upper Pennsylvanian Kansas-type cyclothems. Chemical Geology 206, 289-318.