During 1962, 645 wells were drilled in western Nebraska, a 35% decrease from the record year of 1961. The 381 exploratory wells resulted in 33 discoveries (success ratio of 8.7%). Important developments in 1962 include the following: the expansion of the Cambridge arch productive area; the northward and northeastward spread of the search for Paleozoic oil into sparsely drilled N.-central Nebraska; the rapid expansion of Lansing production at Silver Creek field; and a renewal of the search for Minnelusa oil in northwestern Nebraska. Oil production in Nebraska was 24,691,779 bbls, a 4% increase from 1961. During 1962, 810 wells were drilled in Colorado, representing a 19% increase from 1961. The 449 exploratory wells produced 50 discoveries (exploratory success ratio 11%). Important developments in 1962 include the following: a surge of exploratory and development drilling in Washington County; the increasing search for pre-Cretaceous objectives around the flanks of the Denver basin; and the continuing search for various stratigraphic and structural objectives in western Colorado. Oil production in Colorado totaled 42,345,559 bbls, a 4.9% decrease from 1961. Geophysical activity increased markedly around the fringes of the Denver basin but decreased enough on the Cambridge arch and in the Paradox basin to show a 12% over-all decrease. In 1963, exploratory activity is expected to taper off somewhat from its 1962 pace.