Crosscutting relationships establish the order of events in a sheeted clastic dike exposed near TriCities, WA. 1.) Injection of yellow clastic dike. 2.) Growth of calcite cement overprints (caliche) along bedding planes in host strata (diagenesis). 3.) Injection of green clastic dike alongside yellow dike and truncation of cement bands. 4.) Injection of blue clastic dike alongside green dike. Three separate fills (1, 3, 4) comprise this composite clastic dike. Its actually th

College students with access to quality information on the geology exposed near their schools will cause Geology professors to raise their game. That's a good thing for all involved. Specific information on classic outcrops and mapping areas should not be hidden away in faculty file cabinets (or memories) and sprung on students in the field. Even if guidebooks, articles, departmental photo galleries, and websites only provide the basics, its better than nothing. By simply pro

Reprint of this article: Cooley, S.W., 2015, The curious clastic dikes of the Columbia Basin (p. 91-92), in Carson, R.J., Many Waters: Natural History of the Walla Walla Valley and Vicinity, Keokee Press, 196 pgs.