Formation of different types of microbial structures (stromatolites) based on environmental changes and sea level fluctuation: an example from Late Cambrian carbonate deposits, NW Kerman, Iran

For study of different types of stromatolites, their modes of growth and their relation to sequence stratigraphy within the Derinjal Formation, three stratigraphic sections at Dahuieh, Gatkueih and Gazueih in SE and E of Zarand (NW Kerman), were measured and sampled with thickness of 160, 140 and 130 meter, respectively. Modes of sediment accretion, trapping and binding of sedimentary grains, together with the morphology of stromatolites and microbial mats in the Late Cambrian are analyzed, in order to show the interaction between the growth patterns, morphology and facies association. Based on morphologic study and modes of growth, 4 main groups of stromatolity including stratiform stromatolite, single and lateral accretion, domed stromatolites, Columnar stromatolites and Coniform stromatolites were identified. Growth environmental analysis shows that these sediments have been deposited in tidal environment. Relation between sea level changes and stromatolite types show that stratiform stromatolite is consistent with early TST and late HST, and domed, columnar and coniform stromatolies have been observed in late TST and early HST.