Travel Reference
In-Depth Information
1
Fossils and the Birth of
the Geological Time Scale
How old are the rocks on Sucia Island? How many years ago were the
greenish sandstone and silts so rich in fossils not the stony outcrops we see
today, but rather a vibrant, living seabed, home to an entire bestiary of ex-
tinct organisms? How long ago did the long-necked, scaly sea reptiles and ar-
chaic shelled mollusks live their lives? How long ago? We cannot bring back
to life this world gone by until we know its age. Finding the age of Sucia Is-
land is our first task in this journey, just as it is usually the first scientific pro-
ject undertaken as by every neophyte geologist.
Geologists face the same central question in all of their studies: How
old is the rock they are studying? For that matter, how old is the earth? When
