The Islands of Blowtorches: Hawaiian Geology

Timeline of Hawaiian History NOT to scale! 85 mya: Earliest Emperor Seamounts visible today are formed 1983: Kilauea Volcano begins to erupt 43 mya: Catastrophic event causes bend in Hawaiian chain 300-750 AD Polynesians arrive from Tahiti in outrigger canoes 1900: Hawaii becomes a US territory 65 mya: The dinosaurs (not native to Hawaii) become extinct 1 mya: Island of Hawaii forms 1778: British explorer Captain James Cook lands on Hawaii 5 mya: Island of Kauai forms 1959: Hawaii becomes a US state and the age of tourism begins

The Hawaiian Islands Overview: Quick Facts

STATE FLAG OF HAWAII

Plate Tectonics and the Hawaiian Chain

The Hawaiian Chain The Hawaiian Islands 6,000 km long! and the Emperor Seamounts And The Story of Pele, Fire Goddess! 6,000 km long! Over 80 volcanoes! Why are these volcanic islands all lined up?

…YES!!!! Further Investigation: Compare Hawaii to Other Pacific Island Chains! Oldest Oldest Oldest Youngest Youngest Oldest Youngest Say, look at all them islands lined up so nice… Youngest Could these four island groups (and more) have been formed by the same process? …YES!!!! (but how?)

The Pacific Plate And Neighbors! THE PACIFIC PLATE… is currently moving west-northwest at a speed of 7 centimeters per year. is subducting under Asia and sliding past North America. is spreading off the coast of the Pacific Northwest. What does this have to do with Hawaii? Common Sense: If a small area in the mantle distorts the crust that passes above it, the distortion in the crust will form a trail, which gets younger in the direction OPPOSITE to the crust’s movement. Observation: The Hawaiian Islands and other Pacific island chains are trails of volcanic islands, which get younger in the direction OPPOSITE to the crust’s movement. Theory: The Pacific island chains were formed as the Pacific plate slid over strange and mysterious “areas” in the mantle. …To be explained later!

Anyway… let’s get down to a question with an answer: Why does the Hawaiian chain have that big bend in it? The rocks at the bend are 43 million years old. Something happened 43 million years ago that caused the Pacific Plate to change direction as it was sliding over the strange and mysterious “area” that distorted it… But no one knows what!! Anyway… let’s get down to a question with an answer: Just what are these strange and mysterious “areas”???

HOT SPOTS!!!! (aka blowtorches) All the Hawaiian islands were formed by volcanic eruptions above the Hawaiian Hot Spot. What is a hotspot ? “…a volcanic region at the Earth’s surface directly above a rising plume of hot, plastic mantle rock.”

Where does the rock that makes up the Hawaiian islands come from? MAGMA!

WE’VE GOT HOT SPOTS ALL OVER THE PLACE Other examples of hot spots include: Cape Verde (off the coast of Senegal), Galapagos Islands (off the coast of Equator), Society Islands (French Polynesia), Tristan da Cunha (southern Atlantic), Yellowstone, Ethiopia Plateau, Lord How (near Sydney), Iceland, and many more.

This graph shows the age of the Hawaiian volcanoes

This shows the heights of these volcanic land masses and their erosion due to age.