WEBVTT 00:01.900 --> 00:04.367 position:10% line:85% size:80% JOAN CARTAN-HANSEN, HOST: LOTS OF DIFFERENT FORCES HELPED 00:04.367 --> 00:06.967 position:10% line:85% size:80% SHAPE ALL THE PLANETS IN OUR SOLAR SYSTEM, INCLUDING THE 00:06.967 --> 00:07.800 position:10% line:85% size:80% EARTH. 00:07.800 --> 00:09.800 position:10% line:85% size:80% FIND OUT MORE ON SCIENCE TREK. 00:09.800 --> 00:16.266 position:10% line:85% size:80% (MUSIC) YEARS OLD. 00:16.266 --> 00:21.066 position:10% line:85% size:80% IT HAS AN INNER CORE OF SOLID METAL SURROUNDED BY A LAYER OF 00:21.066 --> 00:23.166 position:10% line:85% size:80% LIQUID METAL. 00:23.166 --> 00:24.266 position:10% line:85% size:80% THIS IS THE MANTLE. 00:24.266 --> 00:27.166 position:10% line:85% size:80% A MULTILAYERED COLLECTION OF HOT, HEAVY ROCK. 00:27.166 --> 00:29.600 position:10% line:85% size:80% IT'S ABOUT 1800 MILES THICK. 00:29.600 --> 00:31.700 position:10% line:85% size:80% AND ON TOP IS THE ROCKY CRUST. 00:31.700 --> 00:33.367 position:10% line:85% size:80% THAT'S THE PART OF THE EARTH WE SEE. 00:33.367 --> 00:36.800 position:10% line:85% size:80% THE PART WE LIVE ON. 00:36.800 --> 00:39.000 position:10% line:85% size:80% GEOLOGISTS BELIEVE THE EARTH WAS SHAPED BY LOTS OF DIFFERENT 00:39.000 --> 00:41.100 position:10% line:85% size:80% FORCES OVER PERIODS OF TIME. 00:41.100 --> 00:45.066 position:10% line:85% size:80% AND BY STUDYING THE LAYERS OF ROCK AND DIRT, AND EXPLORING THE 00:45.066 --> 00:48.734 position:10% line:85% size:80% CONTOURS OF THE LAND, YOU TOO CAN LEARN HOW THOSE FORCES SHAPE 00:48.734 --> 00:52.166 position:10% line:85% size:80% THE EARTH. 00:52.166 --> 00:56.166 position:10% line:85% size:80% THE SURFACE OF THE EARTH IS MADE UP OF BITS OF LAND KNOWN AS 00:56.166 --> 00:56.367 position:10% line:85% size:80% SLATE. 00:56.367 --> 00:59.266 position:10% line:85% size:80% THESE SLATES -- PLATES ARE MOVING, SLIDING PAST ONE 00:59.266 --> 01:02.633 position:10% line:85% size:80% ANOTHER, FOLDING UNDERNEATH OR BUTTING UP AGAINST EACH OTHER. 01:02.633 --> 01:06.066 position:10% line:85% size:80% THE PRESSURE BETWEEN TWO PLATES BUILDS UP TO MORE THAN THE ROCKS 01:06.066 --> 01:10.367 position:10% line:85% size:80% AROUND THEM CAN STAND, THE PLATES CRACK AND THE ENERGY IS 01:10.367 --> 01:14.800 position:10% line:85% size:80% RELEASED IN WHAT WE KNOW AS AN EARTHQUAKE. 01:14.800 --> 01:17.633 position:10% line:85% size:80% >> YOU CAN SEE WHY AN EARTHQUAKE CAN CAUSE A LOT OF DAMAGE. 01:17.633 --> 01:21.166 position:10% line:85% size:80% PUT TWO BLOCKS TOGETHER AND COVER THEM WITH A LAYER OF SAND. 01:21.166 --> 01:24.000 position:10% line:85% size:80% PUT A FEW BUILDINGS AND ANIMALS ON TOP. 01:24.000 --> 01:26.500 position:10% line:85% size:80% AND THEN MOVE ONE OF THE BLOCKS. 01:26.500 --> 01:29.633 position:10% line:85% size:80% AND THAT'S WHEN AN EARTHQUAKE LOOKS LIKE. 01:29.633 --> 01:32.000 position:10% line:85% size:80% >> EARTHQUAKES ARE MOST COMMON WHERE THE PLATES MEET. 01:32.000 --> 01:34.533 position:10% line:85% size:80% THAT'S KNOWN AS A FAULT LINE. 01:34.533 --> 01:37.867 position:10% line:85% size:80% IDAHO IS NUMBER SIX ON THE LIST OF STATES WITH THE MOST 01:37.867 --> 01:40.367 position:10% line:85% size:80% EARTHQUAKES. 01:40.367 --> 01:44.333 position:10% line:85% size:80% A VOLCANO IS BASICALLY A HOLE IN THE EARTH'S CRUST WHERE LAVA 01:44.333 --> 01:45.433 position:10% line:85% size:80% COMES OUT. 01:45.433 --> 01:50.333 position:10% line:85% size:80% LAVA IS HOT, MOLTEN ROCK. 01:50.333 --> 01:51.700 position:10% line:85% size:80% >> LAVA HAS VISCOSITY. 01:51.700 --> 01:57.500 position:10% line:85% size:80% SOME LAVA, LIKE THIS TOOTHPASTE, COMES OUT THICK. 01:57.500 --> 02:04.066 position:10% line:85% size:80% >> OTHER LAVA LIKE THIS, COMES OUT LIKE LIQUID. 02:04.066 --> 02:08.333 position:10% line:85% size:80% >> EVENTUALLY THE LAVA COOLS INTO ROCK. 02:08.333 --> 02:12.166 position:10% line:85% size:80% >> ANCIENT VOLCANOS CREATED THE TWISTED LANDSCAPE YOU SEE AT 02:12.166 --> 02:15.333 position:10% line:85% size:80% CRATERS OF THE MOON NATIONAL MONUMENT N SOME PARTS OF IDAHO 02:15.333 --> 02:19.000 position:10% line:85% size:80% THE MOUNTAINS WERE FORMED WHEN MAGMA, OR HOT LAVA, STILL 02:19.000 --> 02:23.433 position:10% line:85% size:80% UNDERGROUND, PUSHED UPWARD BUT DIDN'T BREAK THE SURFACE. 02:23.433 --> 02:25.900 position:10% line:85% size:80% THAT'S CALLED A BATHOLITH. 02:25.900 --> 02:30.000 position:10% line:85% size:80% THESE MOUNTAINS ARE PART OF THE IDAHO BATHOLITH. 02:30.000 --> 02:34.266 position:10% line:85% size:80% A LITTLE BIT OF WATER CAN COMPLETELY CHANGE A LANDSCAPE. 02:34.266 --> 02:37.800 position:10% line:85% size:80% OVER TIME, MOVING WATER EATS AWAY AT ROCK. 02:37.800 --> 02:43.533 position:10% line:85% size:80% THE THOUSANDS OF YEARS LATER, WHAT WAS A PLAIN CAN BECOME A 02:43.533 --> 02:43.800 position:10% line:85% size:80% VALLEY. 02:43.800 --> 02:46.533 position:10% line:85% size:80% A FLOOD CAN CHANGE THE LANDSCAPE. 02:46.533 --> 02:49.900 position:10% line:85% size:80% 15,000 YEARS AGO, THE BONNEVILLE FLOOD SCOURED OUT THE SNAKE 02:49.900 --> 02:53.333 position:10% line:85% size:80% RIVER PLAIN, CARVING OUT THE CANYONS AT TWIN FALLS. 02:53.333 --> 02:56.000 position:10% line:85% size:80% AND NOT ALL FLOODS ARE CAUSED BY NATURE. 02:56.000 --> 03:00.734 position:10% line:85% size:80% WHEN THE TETON DAM BROKE IN 1976, A WALL OF WATER ALMOST 03:00.734 --> 03:10.166 position:10% line:85% size:80% WIPED OUT MANY SMALL TOWNS, LUG MUCH OF REXBURG. 03:10.166 --> 03:13.166 position:10% line:85% size:80% >> GENTLE FLOW OF WATER DOESN'T HAVE MUCH ENERGY. 03:13.166 --> 03:16.166 position:10% line:85% size:80% BUT A FLOOD HAS LOTS OF ENERGY. 03:16.166 --> 03:21.700 position:10% line:85% size:80% SO THE AMOUNT OF DAMAGE TO THE LAND DEPENDS UPON HOW MUCH GEO 03:21.700 --> 03:22.867 position:10% line:85% size:80% FORCE IS INVOLVED. 03:22.867 --> 03:25.734 position:10% line:85% size:80% >> GLACIERS ARE RIVERS OF ICE THAT CARVER THEIR WAY THROUGH 03:25.734 --> 03:26.700 position:10% line:85% size:80% THE LAND. 03:26.700 --> 03:30.734 position:10% line:85% size:80% THEY GROW AND PUSH THEIR WAY THROUGH, CREATING U-SHAPED 03:30.734 --> 03:33.533 position:10% line:85% size:80% VALLEY WAS A FLAT BOTTOM AND HIGH SIDES. 03:33.533 --> 03:36.533 position:10% line:85% size:80% EVEN WATER IN THE FORM OF RAIN CAN RESHAPE THE EARTH. 03:36.533 --> 03:40.166 position:10% line:85% size:80% TOO MUCH RAIN ALL AT ONCE CAN CAUSE LANDSLIDES. 03:40.166 --> 03:43.800 position:10% line:85% size:80% AND EVEN GENTLE RAIN AND SNOW OVER TIMING WEAR AWAY THE TOP 03:43.800 --> 03:47.967 position:10% line:85% size:80% PART OF THE EARTH, SHOWING THE HARDER ROCK BELOW. 03:47.967 --> 03:51.900 position:10% line:85% size:80% FREEZING AND THAWING CAN ALSO CRACK ROCKS OPEN, MAKING IT 03:51.900 --> 03:55.266 position:10% line:85% size:80% EASIER FOR WATER TO EAT AWAY AT THE SURFACE. 03:55.266 --> 03:59.166 position:10% line:85% size:80% EROSION, ESPECIALLY OVER TIME, CAN SCULPT THE LAND. 03:59.166 --> 04:02.100 position:10% line:85% size:80% WATER, IN ALL ITS DIFFERENT FORMS, IS ONE OF THE MAJOR 04:02.100 --> 04:04.000 position:10% line:85% size:80% FORCES THAT SHAPE THE EARTH. 04:04.000 --> 04:11.266 position:10% line:85% size:80% WHAT FORCES CARVER THE EARTH WHERE YOU LIVE? 04:11.266 --> 04:14.066 position:10% line:85% size:80% IF YOU WANT TO LEARN MORE ABOUT GEOLOGY, CHECK OUT THE 04:14.066 --> 04:15.500 position:10% line:85% size:80% SCIENCE TREK WEBSITE. 04:15.500 --> 04:18.533 position:10% line:85% size:80% YOU'LL FIND IT AT SCIENCE TREK DOT ORG. 04:18.967 --> 04:24.533 position:10% line:85% size:80% (MUSIC) 04:38.800 --> 04:41.333 position:10% line:85% size:80% NARRATOR: PRESENTATION OF SCIENCE TREK ON IDAHO PUBLIC 04:41.333 --> 04:44.166 position:10% line:85% size:80% TELEVISION IS MADE POSSIBLE THROUGH THE GENEROUS SUPPORT 04:44.166 --> 04:47.166 position:10% line:85% size:80% OF THE LAURA MOORE CUNNINGHAM FOUNDATION, COMMITTED TO 04:47.166 --> 04:49.800 position:10% line:85% size:80% FULFILLING THE MOORE AND BETTIS FAMILY LEGACY OF 04:49.800 --> 04:53.333 position:10% line:85% size:80% BUILDING THE GREAT STATE OF IDAHO; BY THE IDAHO NATIONAL 04:53.333 --> 04:57.533 position:10% line:85% size:80% LABORATORY, MENTORING TALENT AND FINDING SOLUTIONS FOR 04:57.533 --> 05:01.100 position:10% line:85% size:80% ENERGY AND SECURITY CHALLENGES, BY THE FRIENDS OF 05:01.100 --> 05:04.600 position:10% line:85% size:80% IDAHO PUBLIC TELEVISION AND BY THE CORPORATION FOR PUBLIC