Fractal Analysis and Depositional Cycles from Stratigraphic Sequences of the Upper Cretaceous at the Iberian Range (Spain)
Values of Dt obtained from the total thickness of each stratigraphic section range from 0.64 to 1.37. Dt is higher (0.8 to 1.37) in the central area of the Basin, and is lower (0.8 to 0.64) towards the southern coastal margin. These values can be considered as a parameter which reflects the geometrical organization of the 4th-order parasequences in each section.
Values of Dt ranging from 0.8 to 0.64 correspond to sections with both a wide range in bed thickness and thicker strata (around 0.4 m). Values of Dt ranging from 1.37 to 0.8 correspond to sections with more homogeneous bed thickness, composed mainly of thinner strata (around 0.2 m).
Lower Dt values reflect sections with heterogeneous accommodation within mixed terrigenous-carbonate environments. Meanwhile, those sections with higher Dt values correspond to carbonate platform environments with more homogeneous accommodation. Besides, the sections with lower Dt are more sensitive to lateral displacements of the carbonate platform facies belts (progradation or retrogradation).
These preliminary results show that fractal analysis may be a new tool of critical importance in the stratigraphic and dynamic analysis of stratigraphic successions. Fractal analysis can be utilized to get a better insight into the stratigraphical and sedimentological interpretations. It can also be used as a quality control parameter of field data, detecting sections with exposure problems.