Everyone working in a problem as complex as continental drift, must at some time have feit the need for an objective data summary in fields other than his own. It is a scientific dilemma that, aIthough there is evident need for researchers with competence in many fields (the classical natural scientist), the time in- volved in acquiring such broad experience is so great as to ren der the task largely impossible. The alternative seems to be the team approach, and we have espoused it in tbis volume. Editors and contributors alike have tried in this book to keep the accent upon factual...

This trip backward in time capsulizes in a general way the geologic development of the area that is now northern Alaska. The Cretaceous through Recent history is predominantly one of erosion of the ancient Brooks Range and filling of the Colville Geosyncline under processes like those in Operation today. All the rocks older than Jurassic, however, were deposited far from their present sites. One of the intriguing tectonic puzzles involves the geographic positions and relative timing of events that occurred during the orogeny that built the Brooks Range. I suggest that pre-Cretaceous...