Because heat and pressure affect the ratio of radioactive parent to stable daughter, ____ rocks generally are difficult to date accurately by radiometric dating.
A) igneous
B) sedimentary
C) metamorphic
D) mafic
E) felsic

Question

Quizplus · Accepted Answer

Metamorphic rocks undergo significant changes in heat and pressure, which can cause the radioactive parent to become unstable and alter the ratio of parent to daughter isotopes. This makes it difficult to accurately determine the age of the rock using radiometric dating. Igneous rocks (A) and certain types of sedimentary rocks (B) can be more reliably dated using radiometric methods. Mafic (D) and felsic (E) refer to the mineral composition of rocks and are not necessarily indicative of their ability to be dated with radiometric methods.

Because Heat and Pressure Affect the Ratio of Radioactive Parent