This report summarizes results of geologic mapping in the South Umpqua Falls region of the Western Cascade Range in Douglas County, southwestern Oregon (plate 1). Rocks of the Western Cascades range in age from late Eocene to late Miocene and consist of deformed and partially altered flows, pyroclastic rocks, and...
The price of gold has risen from $60.35 per ounce in mid-November, 1972, to $91.25 per ounce in mid-April, 1973. The present high price has caused considerable speculation as to the underlying reasons for the sudden increase and what effect it may have on the international monetary situation. This precious...
Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic,...