San Andreas fault

Earthquakes, large and small, happen every single day along zones that wrap around the world like seams on a baseball. Most don’t bother anybody, so they don’t make the news. But every now and then a catastrophic earthquake hits people somewhere in the world with horrific destruction and immense suffering. On Oct. 7, 2023, a 6.3 magnitude earthquake struck near the historic city of Herat, Afghanistan, leaving more than 1,000 people dead in the rubble, according to estimates. It was followed by two more earthquakes, just as powerful, on Oct. 11 and Oct. 15. A few weeks earlier, on Sept. 8, a 6.8 magnitude earthquake shook ancient villages apart in the Atlas Mountains of Morocco, killing nearly 3,000 people. In February 2023, a large area of Turkey and Syria was devastated by two major earthquakes that hit in close succession. As a geologist, I study the forces that cause earthquakes. Here’s why some seismic zones are very active while others may be quiet for ge...