Ron Harris and Kevin Rey

Structure and Sound: The Tectonic Setting of Iceland and Recent Geophysical Research

Clank! The hammer rang as it struck the metal plate. Swing number four hundred twenty-five. Just seventy-five more, and they'd be done for the day. Professor Kevin Rey, an assistant research professor at BYU focused primarily on geochemistry and geophysics, wiped the sweat off his forehead, setting the hammer down for a brief moment and taking in the fresh Icelandic air. He and his colleague, Professor John McBride, had been battling weather conditions all day as they worked to gather the seismic imaging data that they needed in the region of Reyðarfjörður, tucked away on the east coast of Iceland. The island held many marvels and mysteries, just waiting to be discovered. They were determined to uncover them.

The February 6, 2025 seminar featured two speakers, Professor Ron Harris and Professor Kevin Rey. Professor Harris is an expert in mountain-building processes and their effects on mankind. He is a graduate of the University of Oregon with a B.Sc. in Geology, he has an M.Sc. in Geophysics from the Geophysics Institute at the University of Alaska, and a Ph.D. in Tectonics from University College London. He has enjoyed a successful career as a researcher, a consultant, and a professor, among other things. He currently teaches at BYU. He began the seminar, titled "The Structure and Tectonic Setting of Iceland", with a thrilling discussion on the ravaging Vikings of medieval times. These pillaging warriors rained terror down on the people of Europe for hundreds of years, using Iceland as one of their primary staging bases for their merciless conquests. They were vicious and unforgiving, an unbridled force of nature. Just as the Vikings led raids across all of Europe, so too did the island of Iceland itself.

Iceland is known for its stunning geological features, especially the glacier-covered volcanoes that often spew out ash and lava. Professor Harris recounts the story of Reverend Jon Steingrimsson, who witnessed what would later become known as the legendary Laki eruption. On June 8, 1783, the Reverend was admiring the vast beauty of Iceland when he began to notice a dark cloud looming on the horizon. This was no ordinary storm cloud. No, it was instead the beginning of what would be an eight-month nightmare that devastated the lives of many people in Iceland and in Europe. The eruption was classified as a fissure eruption, where magmatic pressure builds up until it eventually releases out of the Earth's crust, leading to massive fountains of red-hot lava and deadly clouds of toxic gases and ash. Reverend Steingrimsson recorded lava fountains that stretched up to 1400 meters high, as tall as Provo's Kyhv Peak, spewing out at several meters per second. He described the consequences of the eruption, such as the deaths of approximately a fourth of the population of Iceland, genetic mutations in both livestock and humans, and a wide range of sickness and decay. Globally, the Earth dropped in temperature by a significant margin, while ash and debris rained down across much of northern Europe, making this one of the largest volcanic eruptions in recorded history.

The Laki eruption was just one of the many geological phenomena showcased in the seminar. Professor Harris described several more of these, including the 2010 Eyjafjallajökull eruption and the 2011 Grimsvotn eruption that caused severe interruptions to airline travel and colossal tsunami-like glacial floods. He mentioned the rich basalt formations that dot the landscape of the island. He also talked about the Thingvellir National Park, part of the Atlantic Ocean Ridge that runs through Iceland, which is the only place in the world that one can visit to see a spreading ridge, forming a ridge zone of over 100 miles wide. Finally, he spoke on the tectonic evolution of Iceland and the subduction zones of North America that pulled Greenland away from mainland Europe, resulting in the formation of what is now Iceland over a large hotspot.

Professor Rey then came onto the scene with his portion of the lecture. He showed much of the research that he and his colleague Professor McBride have done in Iceland. Standing atop a layer of basalt in Reyðarfjörður, the two researchers had set up camp using geophones, wire, and a hammer to get a diagram of the velocity of sound waves with respect to their frequency, which allows for a better understanding of the timing, the frequency, and the thickness of the layers of rock. It's a time-consuming process, but it's far better than the alternative: digging a trench. Professor Rey finished speaking by discussing the several other research projects that they conducted around the island, which included utilizing ground-penetrating radar, where radar is shot directly into the ground to get more information about the layering under the ground, as well as examining large wave-like bands called ogives that form on the surface of glaciers, which tell researchers more about the seasonality found in the ice.

From ancient volcanoes to wide-open ocean rifts, from titanic glaciers to scorching rivers of lava. The remarkable island of Iceland offers a truly astonishing wealth of geological wonders, making it one of the most unique and notable places in the world and in the field of geology. Professors Kevin Rey, John McBride, and Ron Harris have made both stunning discoveries and compelling observations into the mysteries that Iceland hides, and only time will tell what other exciting developments may occur as more secrets are uncovered.