A Geoscience Digital Image Library

TitleVesicular basalt, Modoc Co., California, USA
DescriptionThis basalt, from northeastern California, contains vesicles (holes) formed when volcanic gases were trapped in the cooling lava. The specimen is 8 cm across. Although not visible in hand specimen, microscopic examination reveals that this sample contains two different sizes of plagioclase crystals - suggesting a two stage cooling history. Abundant fine grained augite is also present.
LocationUSA ▹ California ▹ Modoc. Northeastern California.
PhotographerNessa Eull. 2001-05-16.
CollectionWard’s University Rock Collection #128.
Key wordsbasalt, vesicle, vesicular, California
Tech details935 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera, 60mm Nikon AF micro lens.
GeoDIL number458