A uranium-lead age determined from a zircon crystal removed from a sandstone would reflect the time elapsed since the ________ of the zircon.
A) erosion
B) deposition
C) crystallization
D) cementation
Question 2
In order to use a radioactive-decay scheme to calculate the age of a mineral all of the following conditions must be met except
A) the half-life must be known.
B) no daughter isotope present prior to the start of parental decay or the amount of daughter can be determined.
C) no parent or daughter isotopes can be gained or lost from the mineral once decay starts.
D) only one radioactive isotope can exist in the rock so that cross-decay doesn't occur.
The Calvin Cycle Was Determined by Isotope Labelling Methods
Polycystic kidney disease. Notice the presence of numerous fluid-filled sacs, or cysts, in these kid
Earth’s history is divided into nested sets of time--eons, eras, periods, and epochs--and is called
Healthier choices can be made when time is taken to read a nutrition label.
Denture sore mouth in a patient who never removed partial dentures at night.
The Geologic Time Scale