Based on GR and TH/U values and imaging logging data as well as cores and thin sections which could reveal base level and facies changes,18 high-frequency sequences (fourth-order sequences)are identified in the Lower Carboniferous in Marsel block of southern Kazakhstan. Of them,the Tournasion and Viscan sequences are mainly bounded by instantaneous exposed punctuated surfaces and the Serpukhovian sequence by drowned punctuated surfaces. The high-frequency sequence is usually ten meter to several tens meter thick. The tournasian-early Visean high-frequency sequence is relatively thin and does not vary much in thickness,leading to the result that the whole Lower Carboniferous is thinner in the west and north. Lagoon subfacies on both evaporative and restricted platforms,and tidal flat subfacies on restricted platform were developed respectively in lower and upper part of Tournasian-early Visean high-frequency sequences;subfacies in high-frequency sequences of middle-late Visean-Serpukhovian,is changed from tidal flat on restricted platform to tidal flat and shoal-reef complexities on evaporate platform upwards. After genetic analysis of these high-frequency sequences,it is supposed that periodic high-frequency sea-level and climate changes are dominant factors for high-frequency sequence development,however,climate has a more significant influence on later high-frequency sequence development. What's more,it is indicated that the Marsel block was located in the inner part of a regional rimmed carbonate platform,mainly evolved through three stages in Early Carboniferous: Early (Tournasian)restricted-evaporative platform,middle (Visean)restricted-evaporative platform and late (Serpukhovian)open-restricted-evaporative platform. Obviously,the study of high-frequency sequence could lay the foundation for high-resolution sequence stratigraphic framework construction and detailed favorable reservoir identification,correlation and prediction.