Abstract. The waveform or character of a refraction arrival has become internationally important because of its use in determining source parameters. An approximate theoretical machine calculation has been made to show the effect of layering above a refractor on the character of the refraction arrival. The method is illustrated with a geologic model taken from the Edwards Plateau area of West Texas. The effect of the Edwards limestone, Comanche, and Trinity formations on the refraction from the Pennsylvanian limestone is computed. The conversion of energy in theses upper layers from compressional to shear plays a significant role in forming the refraction character. An anticlinal structure is introduced into the Pennsylvanian limestone and it is argued that, in a first approximation, the wave in the Pennsylvanian limestone follow the structure, refracting off at the critical angle as before. Now, however, the angle of incidence on the base of the Trinity is a function of the angle of the structure. Since the amplitudes of converted waves depends n this angle, The character of the refraction arrival depends in a predictable way on the angle in the structure where the critical refraction has taken lace. These results are theoretical and only approximate, but …

Abstract: "A particularly conventional modified form of Maxwell distribution is chosen. The modified expressions for (a) the energy transfer from the ions to the electrons in a plasma and (b) the brehmestrahlung from the electrons are calculated. Using the expressions some possible steady-state conditions for the ion and electron gases are derived and compared with those for the usual Maxwell distributions."

From abstract: "Within the framework of age theory an expression is developed which represents the probability of a neutron being reflected with an energy loss corresponding to age, v, as a function of reflector thickness."