Dating recent lava flows
Although no Indian legends attribute them to recent eruptions, one early geologist remarked about the extraordinary freshness of the lava: "It looks as fresh as any coulee of Vesuvius ejected twenty or thirty years ago." One K-Ar "model age" determination gave 1.2 0.2 million years for the lava dam, 3 and geologists consider these lava flows to be Pleistocene in age.Rubidium-Strontium Data Rubidium, a trace element which is chemically similar to potassium, is naturally radioactive.New analyses of Grand Canyon rocks allow the popular rubidium-strontium isochron method to be evaluated.Grand Canyon Lava Flows Two lava-flow formations occur in the Grand Canyon: the Cardenas Basalt and the western Grand Canyon lava flows. Both are basalts, and both should be ideal for radioactive isotope dating.Four whole rock samples and one feldspar sample separated from one of the whole rock samples were submitted independently to three different laboratories for testing.
Have these claims of hundreds of millions of years with Grand Canyon strata been verified?Some of the lava flowed over the north rim, cascading into Grand Canyon, forming spectacular "frozen" lava falls.Several lava flows even reached the river, forming lava dams.The western Grand Canyon lava flows are among the youngest formations of the Grand Canyon.The youngest flows came from volcanoes on the Uinkaret Plateau north of the Colorado River.