2026 earthquake activity remains within normal range
A succession of powerful earthquakes across Latin America and Asia has made 2026 feel unusually active, but the global number of major earthquakes remains within normal statistical ranges, according to two earthquake specialists who spoke to Anadolu.
Eleven earthquakes of magnitude 7 or greater have been recorded worldwide so far this year, compared with a long-term average of about 16 such events annually.
“There are, on average, about 16 magnitude 7+ events per year. There have been 11 so far this year, so it is a very typical year,” said Richard Styron, senior active faults specialist at the Global Earthquake Model Foundation.
The US Geological Survey says the world typically experiences about 15 magnitude-7 earthquakes and one magnitude-8 or greater earthquake in an average year.
Dr. Margarita Segou, an earthquake seismologist at the British Geological Survey, also said the current figures remain within normal year-to-year variation.
Clusters do not mean a surge
Several major earthquakes occurring within weeks of one another can create the impression that global seismic activity is increasing. Scientists say such clustering can occur naturally even when earthquakes are completely independent.
“Truly independent events often appear clustered, but this is purely coincidental,” Styron said, describing the pattern as a Poisson process, in which random events can produce both clusters and gaps.
Segou said similar concerns have emerged during previous periods of frequent earthquakes. Research following a notable sequence in 2014 also found activity remained within expected statistical limits.
Regional activity can vary considerably, however. Indonesia, Colombia and Venezuela have different tectonic settings and earthquake patterns.
Indonesia, for example, has averaged one or two earthquakes larger than magnitude 7 annually over the past decade, according to Segou. The magnitude 7.7 Flores Sea earthquake on Aug. 14 therefore remained within the country's observed range.
Powerful events become headlines
Recent earthquakes have received particular attention because of their locations, impacts and secondary hazards.
A magnitude 7.4 earthquake struck western Colombia on Aug. 10. The Colombian Geological Service recorded it at a depth of about 103 kilometers and described it as the country's largest recorded earthquake of the 21st century. More than 20,000 reports were received from people who felt the shaking across more than 1,200 population centers.
Four days later, a magnitude 7.7 earthquake struck beneath Indonesia's Flores Sea at a much shallower depth of about 15 kilometers, according to the country's Meteorology, Climatology and Geophysics Agency. The offshore reverse-faulting earthquake generated a tsunami and was followed by thousands of aftershocks.
Those events followed a magnitude 7.8 earthquake south of the Philippines on June 7, a magnitude 7.5 earthquake near Venezuela on June 24 and a magnitude 7.3 earthquake off southern Mexico on July 17.
Their proximity in time and the damage and hazards associated with some of them have contributed to the perception of an unusually active year.
Aftershocks are part of adjustment
Earthquake triggering is a genuine phenomenon, but scientists say its effects are strongest close to the original rupture and within a short period, particularly in aftershock sequences.
Segou said scientists increasingly use the term “triggered seismicity” to describe earthquakes influenced by changes in stress following a major rupture.
“The Earth's crust is trying to rebalance to get to a new state,” she said.
The redistribution of stress can produce additional earthquakes and aggravate damage in areas already affected by a major event. Scientists can use changes in stress around a rupture to estimate where aftershocks are more likely and provide short-term probabilities for their number, location and magnitude.
Styron said the area in which triggering may occur generally grows with the size of the initial earthquake, estimating a rough scale of 1 kilometer for magnitude 5 events, 10 kilometers for magnitude 6 and 100 kilometers for magnitude 7 events when the timing is very close.
At greater distances and longer intervals, evidence for triggering becomes considerably weaker.
Seismic waves from very large earthquakes can travel around the planet and disturb faults far from the original rupture, but scientists have found only weak evidence that they can trigger very small earthquakes at great distances.
“There is no evidence or physical mechanism known to support triggering of large events over great distances,” Styron said.
That makes a direct link between the recent Colombian and Indonesian earthquakes unlikely without detailed event-by-event analysis.
Better monitoring improves detection
Advances in seismic monitoring can also make earthquake activity appear greater than it was in the past.
Denser seismic networks, machine learning and artificial intelligence allow scientists to identify much smaller earthquakes that older monitoring systems could not detect.
“These small magnitude earthquakes, although there are more, they're not necessarily felt by the population, but they have a very significant scientific value,” Segou said.
More detailed earthquake catalogs help researchers track seismic sequences, identify interactions between events and improve short-term forecasting. They do not, however, explain an increase in major earthquakes because global records of large events have been relatively complete for decades.
“The global record of major earthquakes is very complete for the past 50+ years. We are seeing very typical numbers of events this year,” Styron said.
Human exposure drives disaster risk
Earthquakes themselves are not caused by population growth or population density, but exposure determines how destructive they become.
The human impact depends on factors including the location and depth of the rupture, the strength and duration of shaking, local ground conditions, building standards, infrastructure resilience and the number of people exposed.
For now, the global earthquake count provides no evidence that Earth has entered a new period of unusually high major seismic activity. The year may feel more restless, but the numbers remain within the range scientists expect.
Source:AA
