Interpreting the Geologic History of an Outcrop

Assume a 50-million-year half-life for the radioactive decay of parent to daughter atoms. Sample ID and description Number of parent atoms Number of daughter atoms Rock age Sample A - granite cobble from conglomerate 625 19375 Sample B - basalt from lava flow 100 700 Sample C - basalt from dike 1000 3000 1. Calculate the ages for the three samples and write these ages in the last column of the table. 2. How old is the dinosaur bone? 3. How old is the clam and what does it suggest about the age of the sandstone? 4. Using only the data available to you on this page, what is the absolute age (i.e., millions of years), or possible range of absolute ages, for when the conglomerate was deposited?