The last decade has witnessed the expansion of field work and the recovery of many important new fossil vertebrates from a number of areas in the Rocky Mountain Interior. This has resulted in (among other things) discovery of many previously unknown taxa and of much better preserved specimens of known forms, significant geographic and temporal range extensions, the development of greater temporal resolution and sampling density for many taxa (leading to much more precise biochronology), and the creation and applicaton of models for examining faunal relations and evolutionary patterns. When the opportunity for this symposium arose, we were faced with the dilemma of how to incorporate as much of this new information as possible, yet limit the resulting monograph to manageable proportions. We decided to confine the subject matter geographically and temporally, to a region and a time span with which we are most familiar and within which much of the exciting new research is now being conducted—the latest Cretaceous and early Tertiary of the northern Rocky Mountain region. This volume is derived from papers presented at that symposium on May 2,1987, at the annual regional meeting of the Rocky Mountain Section of the Geological Society of America, held at the University of Colorado in Boulder <...>

A typical debris flow is a torrential flow of a mixture of water, mud and debris that suddenly pushes ahead with a vanguard of huge, jostling and roaring boulders. It is certainly a very fearful phenomenon that causes disasters, but it is also truly a wonder of nature exciting the curiosity of researchers as to how such a phenomenon can arise. The phenomena themselves had been recognized since ancient times in Japan and given various mnemonic names to make people aware of the dangers. Although there were several detailed witness records around in 1965 when I began working for the Disaster Prevention Research Institute of Kyoto University (hereafter called DPRI), the characteristics and mechanisms of debris flows were still vague, and it was called a ‘phantasmal disaster’.

In geologic terms, a plate is a large, rigid slab of solid rock. The word tectonics comes  from the Greek root "to build." Putting these two words together, we get the term plate tectonics, which refers to how the Earth's surface is built of plates. 
The theory of plate tectonics states that the Earth's outermost layer is fragmented into a dozen or more large and small plates that are moving relative to one another as they ride atop hotter, more mobile material. The diagrams below show the break-up of the supercontinent Pangaea (meaning "all lands" in Greek), which figured prominently in the theory of continental drift -- the forerunner to the theory of plate tectonics. <...>