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A season of unusually high flooding in the African country of Namibia has scientists scrambling to gather data. The normally arid country has turned green due to an intense rainy season that has caused its sluggish streams to overflow. Rivers that normally dry up before making it to the ocean, are delivering tons of water and sediment when they meet the sea.

It is this sediment that scientists are interested in. The geological makeup of Namibia is one that has baffled scientists for some time. There are the normal plains, dunes, and plateaus that would be expected of an arid country. There are also unusual bedrock outcroppings and drainage patterns that scientists would like to understand better.

The sediment deposits along rivers go a long way in telling the story of how the land drains. As water flows, it picks up sand, dirt, and minerals and deposits them on the shores of the river as it makes its way to the sea. Analyzing the content of the sediment deposits helps the scientists trace where that sediment came from.

The scientists use GPS tracking to map where they have been, and to plan where they are going next. They coordinate to create the best strategy for data gathering, and use the GPS data to map the sediment patterns they find. The primary goal of this endeavor is to find the erosion patterns of the land. The heavy rain has brought a number of elements to the surface that were unexpected, and require more research to understand.

With the help of GPS technology, the scientists track their data on a map, looking for specific elemental isotope patterns. Paul Cutler, program director of the NSF Division of Earth Sciences, explains, “The research focuses on the use of isotopes of the chemical elements beryllium, cesium, and lead to measure erosion rates and determine sediment sources.” These isotopes, found primarily in mineral quartz, tell the story of the path the water took to get there. The isotopes also serve to indicate the age of the elements found in the sediment.

Without the help of GPS, the scientists would be following the path of those from centuries ago, following a map, hoping they do not get lost. The flooding has made navigating the area even more difficult, leaving behind areas of deep mud that will suck in a 4 wheel drive truck and render it immovable. GPS takes the guessing out of navigation and allows the scientists to devote their full attention to avoiding mud pits and finding the best sediment deposits.

Article Written by Mark Rummel