look at the figure below. the contact between the unkar group and the tapeats sandstone is a(n); if the relative ages of two formations are known, what else about them can be inferred?; radiometric dates applied to sedimentary rocks produce ages that; magnetostratigraphy takes advantage of the fact that the earth’s magnetic field; dendrochronology involves dating of historic and geologic events through the study of; as understood by modern geologists, the principle of uniformitarianism implies that; which of the following is always the same for different isotopes of a single element?; how is the half-life of a radioactive parent isotope defined?