This volume reports the results of a symposium held in Heidelberg during the International Sedimentological Congress in late August and early September, 1971. The symposium, co­ sponsored by the International Association for Mathematical Geology, entertained the subject, "Mathematical Models of Sedimentary Processes. " The subject is most appropriate because sedimentologists have long been concerned with processes and mechanisms of sedi­ ment dispersal. Much effort has gone into building physical models such as flumes, stream tables, wave tanks, wind tunnels, etc. , to help understand sedimentological processes. Quantita­ tive methods (especially statistics) have been utilized in summarizing these data. It is timely then with the recent developments of simulation and application of computer tech­ niques that a symposium be addressed to the use of "Mathematical Models of Sedimentary Processes" involving some of these new statistically oriented methods and available data bases. Experimentation in geology has been hampered by a scale factor. That is, it is difficult to find suitab. 1e materials for physical models; it is difficult to find a mechanical de­ vice which properly represents the forces involved; it is almost impossible to allow adequately for geologic time. Sta­ tistically valid models are difficult to obtain with physical models because of material replicate problems. Most problems including the time factor, however, can be eliminated with mathematical models. Mathematical models can be infinitely varied in any number of combinations easily and quickly with the computer.

Optimization criteria for mathematical models used in sedimentology.- Interpretation of complex lithologic successions by substitutability analysis.- Mathematical models for hydrologic processes.- Mathematical search procedures in facies modeling in sedimentary rocks.- Monte Carlo simulation of some flysch deposits from the East Carpathians.- Diffusion model of sedimentation from turbulent flow.- Conditional simulation of sedimentary cycles in three dimensions.- Areal variation and statistical correlation.- Formation and migration of sand dunes: a simulation of their effect in the sedimentary environment.- Mathematical models for solution rates of different-sized particles in liquids.- A simple quantitative technique for comparing cyclically deposited successions.- Models for studying the occurrence of lead and zinc in a deltaic environment.- The semi-Markov process as a general sedimentation model.