Himalaya Formation

     THE HIMALAYAS ALREADY HAVE THE TALLEST MOUNTAINS IN THE WORLD, BUT
THEY'RE STILL GROWING.  THE MOUNTAINS FORMED AS ASIA AND INDIA HAVE
STEADILY PLOUGHED INTO EACH OTHER OVER THE PAST 50 MILLION YEARS.  THIS
MAKES THE EARTH BUCKLE TO FORM PEAKS SUCH AS MT. EVEREST, SOME 29,000 FEET
HIGH.  BUT, SAYS GEOLOGIST DOUG NELSON AT SYRACUSE UNIVERSITY, NO ONE
REALLY KNOWS THE DETAILS OF HOW THAT WORKS.

Nelson: "We don't know. . . exactly how the crust is deforming, for instance we don't know if India is
sliding beneath the continental crust of Asia, or whether both the Indian crust and the Asian crust are
shortening, squishing. . .up."

     NELSON IS ONE OF THE LEADERS OF AN INTERNATIONAL TEAM OF SCIENTISTS
TRYING TO DETERMINE JUST HOW THE HIMALAYAS WERE FORMED.  THE GROUP IS
MAPPING THE EARTH'S CRUST UNDERNEATH THE HUGE MOUNTAIN RANGE.   THEY  MAP
IT BY LISTENING TO IT.  WITH A CARAVAN OF OVER A HUNDRED PEOPLE, THEY DIG
DEEP HOLES IN WHICH THEY SET OFF CONTROLLED EXPLOSIONS.  

(sfx: boom!). 

THEY THEN LISTEN TO THE ECHOES 

(sfx: boom echoes)  

WITH THOUSANDS OF MICROPHONES SCATTERED OVER ABOUT 4 MILES.  A COMPUTER
CAN MONITOR THOSE ECHOES AND BY FIGURING OUT HOW THEY BOUNCED AROUND
INSIDE THE EARTH, PRODUCE AN ACCURATE MAP OF THE CRUST.

     Nelson: "If you want to think of it, it's . . . analagous to a sonogram. If you . . . were pregnant and
wanted to see  your baby, the doctor might do a sonogram.  Well, the principle is the same, what we're
doing is a sonogram of the earth." 

     THE GROUP HAS ALREADY GONE ON TWO TRIPS TO THE HIMALAYAS TO
COLLECT DATA, AND HOPE TO CONTINUE TO GO EVERY COUPLE OF YEARS OVER THE
NEXT DECADE.  FROM THEIR CURRENT FINDINGS THEY SUSPECT THAT THE INDIAN
CONTINENT HAS DIPPED BELOW THE ASIAN CONTINENT. AS INDIA CONTINUES TO SLIDE
NORTHWARD IT IS SCRUNCHING UP THE ASIAN CRUST AS IF IT WERE A BIG SNOW
PLOUGH PUSHING SNOW.  EVENTUALLY INDIA WILL COME TO A STANDSTILL, AND THE
PROCESS WILL REVERSE, AS THE HIMALAYAS SINK AND ERODE BACK TO SEA
LEVEL--BUT DON'T WORRY, THAT SHOULDN'T HAPPEN FOR ANOTHER FIFTY MILLION
YEARS.