Researchers at the James Cook University have discovered that it is possible to get clues and information regarding earthquake damage through the analysis of ancient soil. The team of experts studied the land features of earthquake-stricken lands and found evidence that can help predict the future danger of earthquakes in developing countries.
The study led by Hannah Hilbert-Wolf assessed the grounds of Mbeya in Tanzania, where a massive earthquake happened about 25,000 years ago. Together with supervisor Dr. Eric Roberts, the team utilized modern methodology in evaluating the land.
The researchers discovered signs of fluidization and liquefaction in the land as a result of the earthquakes. Fluidization refers to the process by which soil acts like a quicksand. Another extraordinary finding is the upward shift of ground materials, which is uncommon in continental lands. This particular finding left experts to think about the outcome of earthquakes when it strikes the rising urban cities of the region.
"This could be a major concern for the growing urban population of East Africa, which has similar tectonic settings and surface conditions," said Hilbert-Wolf.
The current study points to the streak of highly impairing earthquakes that happened this year, such as those that occurred in Papua New Guinea and Nepal, as the research findings may provide valuable insight into the consequences of earthquakes in similar countries.
"What we have shown is that in developing countries in particular, which may lack extensive seismic monitoring, the rock record can be used to not only investigate the timing and frequency of past events, but also provide important insights into how the ground will behave in certain areas to seismic shock," said Hilbert-Wolf.
The most powerful earthquake that ever crashed Africa in the 20th century happened in 1920, where some 7.5 million people settled. Houses and buildings were destroyed, causing fluidization and liquefaction. The population continues to rise in Tanzania as an estimated 130 million people will live in the country by 2050. These people are anticipated to live in highly urbanized areas, where lands are more at risk of land deformation and earthquake devastation compared to traditionally constructed structures.
"We can now use this to evaluate how the ground would deform in a modern earthquake," said Roberts. "This is important because the approach is inexpensive and can be used to model how structures might be affected by future events, providing a valuable tool in hazard assessment."
