March 1999 IN THIS ISSUE: History Rural Institute Chemistry Sociology Geology |
Journeys in the Locked away behind the Iron Curtain, Mongolia had long been a black hole on the maps of Western geologists. That started to change in 1990 when the country shrugged off communism and turned to democracy. Marc Hendrix, a UM assistant professor of geology, was one of the first American geologists to visit a more open Mongolia. Since 1988, the 36-year-old Hendrix has journeyed seven times to Mongolia and four times to western China. In the process, he’s had enough adventures to make Indiana Jones proud and has dug up valuable information about the geology of Central Asia.
“It’s been truly exciting to unravel the earth history of a place that few Western geologists have ever seen,” Hendrix says. “It’s been an epic experience.”
Hendrix, who joined UM in 1994, studies the sedimentary remains of ancient mountains and the relationship between sedimentation and plate tectonics. He calls Central Asia a geologist’s candy store, since it contains the world’s most extensive system of mountains, which have had a long history of development. Hendrix studies the rise and fall of these ancient mountain ranges by examining the sands and gravels that result from their erosion. These sediments are preserved in low-lying areas called basins. Over time these basins can receive sediment from several eroded mountain ranges, acting as a sort of geologic tape recorder. A native of Gettysburg, Pa., Hendrix had never left the continental United States before 1988, when he visited western China as part of a Stanford University research team. He returned several times, and the line of mountains and other geologic structures the team studied in China pointed them toward the Gobi Desert in southern Mongolia. Hendrix visited Mongolia for the first time in 1991 — one year after the place became an independent country — to pave the way for future expeditions, and he has been back nearly every summer since for geologic field work.
Mongolia is probably best known for being the homeland of Genghis Khan, the 13th-century ruler whose armies swept out of their harsh land to forge the greatest land empire the world has ever known. Today the country also is known as a premier place to hunt dinosaur remains. Mongolia is roughly one-quarter the size of the United States. About one million of the nation’s 2.5 million inhabitants live in the capital of Ulaanbaatar, while many of the rest roam the countryside in a nomadic herder lifestyle little changed since the days of Genghis. These people are still expert horsemen, they still drink cumis — fermented mare’s milk with an alcoholic kick — and they still live in gers — dome-shaped felt huts. Hendrix’s first major trip into the wilds of Mongolia in 1992 was a 1,500-mile trek across the western and southern portions of the country. He traveled with a team of two other Americans and five Mongolians in Russian-made troop transports. Since the entire country has only a few hundred kilometers of paved road, most of the trip was made on unmaintained dirt tracks. Many rivers have no bridges, so the team had to ford them with the transport vehicles. Under such conditions it took the researchers a week to cover 500 miles. As the group traveled across the Asian wilderness, they often would stop at gers to sample Mongolian hospitality. “The people in Mongolia are exceedingly good-natured,” Hendrix says. “They share a love of life and tradition that seems rare in most Western societies.” Hendrix’s Mongolian research had three goals: to collect base-line data about the geology of the area, since almost nothing is known; to learn if the mountain-building events that occurred in China during the Mesozoic Era — 98 million to 245 million years ago — also had occurred in Mongolia; and to explore for signs of petroleum.
Hendrix has discovered that about 160 million years ago much of southern Mongolia was squeezed together, giving rise to a large mountain range. These mountains became so immense that they began to collapse under their own weight — much the same way a souffle that is too tall will begin to spread out under its own weight. During this period of collapse, portions of southern Mongolia were pulled apart to such a large degree that the upper half of the earth’s crust slid completely off the lower half over a period of several million years. This process left the lower half of the crust exposed on the earth’s surface for Hendrix’s teams to study. The geology of the Gobi Desert in southern Mongolia is especially interesting to Hendrix, and his research groups have spent a lot of time working there. He says part of the Gobi contained a Soviet oil field in the late 1960s that was abandoned after a refinery fire. Since there were no environmental regulations at that time, oil workers left without capping the wells, resulting in lakes of oil on the surface. Among the more interesting discoveries made by a Hendrix team was a petrified forest blown down by a large volcanic eruption. The team also found remains of Mongolia’s most ancient dinosaur — the right foot of a Late Jurassic sauropod called Memenschisaurus. It’s one of the only dinosaur finds reported so far in western Mongolia. Also, with their varied discoveries, Hendrix says his expeditions have had their share of adventures. On his first trip, for example, one of the transports rolled while he was riding in its canvas-covered bed. “It was complete chaos,” he says. “Of course there were no seat belts.” The truck came to rest upside down, and Hendrix was knocked unconscious for a few moments. “When the truck stopped rolling, I was lying on the desert sand with my legs still stuck in the truck,” he says. “I panicked a little when I couldn’t move my legs, but then I realized people inside the truck were lying on them.” Fortunately his team survived that event with only concussions, bumps and bruises. Another bad situation took place two years ago when they wandered into a remote corner of southwestern Mongolia, out past the last ger. The area was extremely dry and had no local water supply. Heat soon claimed two of their four trucks, and the field party found itself rationing the last few gallons of water. Hendrix and two Mongolians set out in one of the surviving trucks to scout in the desert, checking any patches of greenery for signs of water. They eventually found an old well used for watering horses. Their research also has taken them within a mile of the Chinese border, into a no man’s land where they needed an escort by Mongolian soldiers. Hendrix was unnerved to see Chinese border guards observing them from a distance. “The Mongolian army appears to be out of money,” he says. “The two soldiers with us weren’t given clips for their guns until just before we were about to depart for the field. At one point we passed an army outpost and were told the two guards there had to walk the 50 miles from the army base to the outpost because no other form of transportation was available.” Hendrix loves the travel associated with geology, and he enjoys giving students a Mongolian experience. UM graduate students Derek Sjostrom and Mary Beck and undergraduates Wendy Krischner and Bob Lenegan have trekked with him to some of the remotest corners of central Asia. “It’s fun for me to see their reactions when we go into a ger for the first time,” he says. “That’s the fun thing about geology — you pretty much have to get out into the field and go where the rocks are.” -- Cary Shimek Photos courtesy of Marc Hendrix |
