GEOL 3032 Chapter : Lec15 Sedimentary Texture Part2
Document Summary
Sorting: a measure of the range of grain sizes present and the magnitude of the spread or scatter of these sizes around the mean size. Graphical method (cid:149) mathematical expression of sorting is standard deviation. Graphical method (cid:149) skewness: the degree of asymmetry of the distribution. Moment method (cid:149) direct use of raw data, without a graphical representation of data (cid:149) mathematical method to calculate the grain size parameters (cid:149) use a computer to calculate a batch of sediment samples (cid:149) efficient. Generic application (cid:149) coarse nearby, fine farther (cid:149) sorting longer transport, more well sorted (cid:149) roundness longer transport, more rounded. Relation of sediment dynamics to populations and truncation points in a grain-size distribution as revealed by plotting grain-size data as a cumulative curve on log probability paper. Particle shape (cid:149) form (cid:149) roundness (cid:149) surface texture. Particle shape - form (cid:149) the overall configuration of particles (= sphericity)
