The Galápagos Islands - Adventure Guide to Ecuador and the Galapagos Islands - page 383

lands, and more than 40 are islets. The largest is the 80-mile-long
Isabela Island, with over half the archipelago's total land area. All
told, the islands extend for more than 267 miles. It would take quite
some time to visit them all.

Geologically, the Galápagos were formed as a result of the same pro-
cess that created the Andes. In fact, the islands (and the Andes) are
still being built, as plate tectonics dictate land formation here. The
enormous underwater Nazca plate , as it moves slowly east toward
the South American plate , passes over a hot spot in the earth's
crust. Magma continues to rise from the core of the earth through the
crust and creates volcanic islands. Currently, the islands are moving
southeast toward South America at the rate of a couple of inches per
year. Thus, the oldest of the Galápagos, Isla Española (over three
million years old), is also the southeasternmost in the archipelago.
Ultimately, the current Galápagos formations may join South Amer-
ica, but neither the currently exposed islands nor human beings are
likely to be around to witness the meeting.

The majority of the Galápagos landmass lies well below the surface of
the ocean and spreads east toward the mainland. There are addi-
tional underwater volcanic formations that were most likely exposed
islands at one time, but which now lie deep underwater. Some are as
old as nine million years and stretch well beyond the Galápagos to-
ward the mainland.

Isla Fernandina and Isabela are the two youngest islands in the
Galápagos chain, dating back only 750,000 years. In fact, much of the
Galápagos chain is still being formed, and the region is considered to
be one of the most volcanically active areas in the world. The land it-
self, formed from the volcanic basalt, consists of rounded cones and
gentle slopes - very different from the jagged peaks of the Andes on
the mainland.

Climate

T

he Galápagos are located directly on the equator, but
are exposed to various natural cooling forces, result-
ing in a pleasant year-round temperature. From June
through December, the cold Humboldt Current from
Antarctica and the warm equatorial current from the north meet
on the islands' shores to create a cool and misty season known as la