00725nam a2200181 a 450000500170000000800410001703500150005805000240007310000250009724501500012226000490027230000130032144000710033465000400040565000480044565000260049370000240051920260817162123.0                                          a.b10066627  aQE75 P9 no. 1049 -C  aOlson, Jerry Chipman 0aAlkalic rocks and resources of thorium and associated elements in the Powderhorn district,bGunnison County, Colorado, by... and David C. Hedlund  aWashington :bU. S. Govt. Print. Off.,c1981  aiv, 34 p 0aUnited States. Geological Survey. Professional paper ;vno. 1049-C 0aThorium oresxColoradoxGunnison Co 0aIntrusions (Geology)xColoradoxGunnison Co 0aAlkalic igneous rocks1 aHedlund, David Carl