The American Journal of Science, Band 251

Alaska Alaska Highway analysis assemblage augite basin beds boulder field breccia brucite cave cent clay minerals cliff coenocytes column composition Cook County Creek crystals curve Cushendun deposits differences dikes dolerite dolerite-pegmatite dolomite drumlins esker Espinaso volcanics fault fauna feet figure flow formation formed fossils fragments friction cracks Geol glacial Glass grains gravel Hall hydrotalcite illite indicate intrusive Island Island Magee Jour kaolinite Lake lamellae lava limburgite limestone loess lower margin material maximum metasomatic miles montmorillonite muskegs olivine Ordovician orientation outcrops pahoehoe pigeonite plagioclase plane plate Pleistocene pollen Postglacial present quartz quartz latite region River rocks samples sand sea level sedimentary sediments shale shear Shoreline sill silt slope soil species spinel spruce structure surface temperature thick thin section tion twinned U. S. Geological Survey Valders valley variance velocity Wisconsin York Yukon zone