关键词: 生长地层, 生长不整合, 逆冲-褶皱造山带, 前陆盆地, 寺口子剖面

Abstract: Growth strata (i.e. progressive unconformities) are linked to a particular structure at depth and a record for different tectonic and sedimentation processes. they locate in foreland basins on the fronts of fold and thrust belts and exhibit extremely varied attitudes. The inherent synchroneity of growth strata and coupled fold or fault activity make growth strata crucial to interpret fold-and-thrust geometry and kinematics. On the balanced cross-section the sequences of growth strata have characteristic wedge-shaped sedimentation. In coeval depositional systems, fault-bend folding, fault-propagation folding and detachment folding are interpreted as the dominant mechanisms. The other modes of folding are recognized later in the 1980s,for example, Trishear folding and Chester and Chester folding, and so on. Though several types of theoretical behavior are expected, all growth strata can be grouped into two fundamental mechanisms: hinge migration and Limb rotation. Growth strata result from a simultaneous interference of several processes such as tectonics, sedimentation and erosion. The interplay between tectonic and surface processes has been shown to constrain the evolution of orogens through a feedback mechanism, the competition between tectonic uplift and shortening, syntectonic sedimentation rate and syntectonic erosion rate controls the final shape and the occurrence and geometries of fault breakthrough in thrust-related anticlines. According to variety of limb and hinge, synsedimentary wedge, variety of strata occurrence and thickness and regional geological setting, growth strata can be identified. In the future, the study of thrust-related folding processes within folds and thrusts belts will be developed by multi-models and ways. Synchroneity and continuity of growth strata and coupled fold or fault activity can be depicted accurately. Based on the present work and good examples of growth strata, paleomagnetic stratigraphy can provide some important information about chronology and tectonic process. Through reviewing briefly the importance, geometry and kinematics of growth strata, we conclude that the Sikouzi section should be a molasses basin occurring in the front of thrust-fold mountain belt where there exist growth strata and progressive unconformities. However,detailed investigation should be done on this in the future.

Key words: growth strata, progressive unconformitie, thrust-fold mountain belt, foreland basin, Sikouzi section