1:45 PM - 3:15 PM
[O05-P76] Fine Laminetede Structure of Stromatolite Suggests Seasonal Climate Change in Cretaceous Period
Keywords:Stromatolite, laminae, photosynthesis
I sutdied the causes of the fine laminated structure of the Cretaceous Stromatolite which was collected in the Andes in Bolivia. The structure consists of alternately laminated light colored laminae and dark colored laminae. The light colored laminae are mede up of crystallized,grown CaCO3 grains. The dark colored laminae are composed of rounded fine grained Carbonate clastics. In short,crystallization and deposition of CaCO3 form the two different laminae.
I predict that the photosynthesis of Cyanobacteria can be related to the deifferent forming of the laminae. In winter,when the photosynthesis becomes anactive, the concentration of CO2 in seawater becomes high. During this period, fine grained Carbonate clastics deposit on the surface of the Stromatolite. In contrast, the concentration of CO2 in seawater becomes low because the photosynthesis becomes active in summer. During this period, CaCO3 crystalize on the surface of the Stromatolite. In conclision, the light colored laminae are formed in summer, and the dark laminae are formed in wonter.
I suggest the fine laminated structure of Stromatoite is caused by the seasonal climate change in the Cretaceous period.
I predict that the photosynthesis of Cyanobacteria can be related to the deifferent forming of the laminae. In winter,when the photosynthesis becomes anactive, the concentration of CO2 in seawater becomes high. During this period, fine grained Carbonate clastics deposit on the surface of the Stromatolite. In contrast, the concentration of CO2 in seawater becomes low because the photosynthesis becomes active in summer. During this period, CaCO3 crystalize on the surface of the Stromatolite. In conclision, the light colored laminae are formed in summer, and the dark laminae are formed in wonter.
I suggest the fine laminated structure of Stromatoite is caused by the seasonal climate change in the Cretaceous period.