Travel Reference
In-Depth Information
west, crossing the wide Strait of Georgia with the mountainous Vancouver
Island looming in the distance. Once you arrive on these eagle-infested
Canadian islands, it is clear that you are out of the United States: better beer,
worse food, no Starbucks coffee (but mercifully no McDonalds either), and
everywhere the lilt of Canadian English with the distinctive "ehs" creatively
interspersed in every sentence. These islands are long and thin, carved by
the glaciers with a north-south whim, and they form a rampart that seems to
protect Vancouver Island from an encroaching North America. One of the
longest of these islands is Gabriola Island. Its few, rare ammonite fossils tell
us that its strata are not so old as the rocks of Sucia. Gabriola contains some
of the youngest, and thus last-formed, rocks still of Mesozoic age in all of
western Canada. Somewhere buried in its youngest rocks is a Cretaceous/
Tertiary boundary site, the boundary between the Mesozoic and Cenozoic
Eras now thought to have been formed by the impact of a giant comet 65
million years ago.
An ancient giant clam
The rocky northern coast of this island is largely uninhabited, although a
road still gives access to it. One can easily find a trail through the salal and
huckleberries, scrambling past the red-barked arbutus trees and onto a beach
replete with strata. Black shale greats us, a shale dense with fossils and living
oysters, and sometimes it is hard to tell the dead from the living. The fossils
don't jump out at you, but they seem ubiquitous once you learn to spot them.
The problem is that these fossils are almost unrecognizable as the remains of
ancient life. They are large, usually the size of a dinner plate but sometimes
as large as 3 feet across, yet so thin that they often appear as only slender
white lines in the middle of sttatal blocks. When we find a particularly large
specimen that has been eroded into view, we can see that it looks like a gi-
gantic oyster with a thin shell, the shell material covered with numerous fine
ribs and some coarser undulations. Well-preserved specimens can be identi-
fied as some kind of giant clam. But how peculiar! There are no 3 -foot clams
on earth today with shells only 1/8 inch thick. These odd clams with nearly
