which slants down to the north beneath the rocks of Zion, which are older than the rocks of Bryce, among others. Many unconformities exist in the walls of the Canyon, including the one below the Precambrian sediments and the one above those sediments. The idea of the river narrowing over time was the hypothesisthat an interested tourist presented to one of the professors and a ranger at the Canyon a few years ago. When the professor asked whether the tourist would want to go out on a narrow point with a jackhammer, the tourist said no, because the rocks might fall off and slide down into the Canyon. When the professor pointed out the many places that rocks had fallen off and slid down, the quick-witted tourist figured out thatthe Canyon has been widened by such rockfalls as the river has cut downward.Points Earned: 1.0/1.0 Correct Answer(s):D6. Early geologists did not have radiometric dating techniques, or long layer-counted histories. Instead, they followed William Smith in putting things in order, and then used uniformitarian calculations based on modern rates of processes and observed results of processes in the geologic record. These early geologists, using these techniques, found that the Earth:Points Earned: 0.0/1.0 Correct Answer(s):C7. You are dating a lava flow by the potassium-argon system. However, the offspring in this system are leaking out of the minerals. Which is accurate?
error.your error.comparing concentrations of offspring from the edges and centers of grains.by comparing concentrations of offspring from the edges and centers of grains.
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