Continental drift is created at spreading centers, and this, along with subduction, drives the system of plates in a chaotic manner, resulting in continuous orogeny and areas of isostatic imbalance. The theory of plate tectonics explains all this, including the movement of the continents, better than Wegener's theory. Hans Stille and Leopold Kober opposed the idea of continental drift and worked on a "fixist" geosyncline model with Earth contraction playing a key role in the formation of orogens. Other geologists who opposed continental drift were Bailey Willis, Charles Schuchert, Rollin Chamberlin and Walther Bucher. In 1939 an international geological conference was held
The Association for the Study of Play been held in North America and Europe, and draw a range of scholars from the fields of anthropology, biology, communication studies, cultural studies, dance, ecology, education, ethology, folklore, history, kinesiology, leisure studies, musicology, philosophy, psychology, recreation, sociology, and the arts. The Association for the Study of Play The Association for the Study of Play (TASP) is a multidisciplinary organization of scholars and practitioners in the field of play. The Association promotes the study of play, forges alliances with organizations advancing play, organizes yearly meetings to disseminate play research, and publishes a newsletter and monograph series. The Association for the Study