Petrology and structure of the pre-Tertiary rocks of Lummi and Eliza Islands, Washington
Abstract
Exposed on Lummi Island are two groups of pre-Tertiary rocks
everywhere in fault contact with each other: a 1300 meter thick
section of turbidite sandstone and mudstone, and rocks largely of
igneous affinity. The latter rocks consist of pillow lavas with
associated radiolarian chert dated as Middle to early Late Jurassic,
and, in a relatively small, isolated exposure, an intrusive
complex containing rocks dated by Pb/U methods as 160 + 3 my.
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- Geology [14]