4.9 Magnitude Quake Strikes Kermadec Islands as Earthquakes Today Shake Global Regions
Multiple earthquakes today ranging from magnitude 3.0 to 4.9 struck various global locations including Chile, Colombia, New Zealand and the United States in the past 24 hours, with the strongest event a 4.9 quake near the Kermadec Islands. [2]
Recent Seismic Activity Overview
A magnitude 4.3 earthquake struck the O'Higgins region of Chile with its epicenter 25-26 km from Navidad. [1] A magnitude 4.1 shallow earthquake hit Chaparral in Colombia's Tolima department and was felt across multiple municipalities in Tolima, Quindío, Risaralda, Valle del Cauca and Caldas. [5] A magnitude 4.9 earthquake occurred at a depth of 35 km near the Kermadec Islands, New Zealand. [2] A magnitude 3.8 earthquake struck 5 km south of Hastings near Havelock North in New Zealand's Hawke’s Bay, felt by thousands and rated as light shaking. [3] A magnitude 3.0 earthquake struck at a depth of 5 km, 28 km southwest of Garden City, Texas. [4] These events form a cluster of earthquakes today reported across different regions within the last day.
Chile O'Higgins Region Temblor
A magnitude 4.3 earthquake struck the O'Higgins region of Chile with its epicenter 25-26 km from Navidad. [1] The epicenter would have been located 26 km from Navidad according to one report and 25 km from Navidad according to another. [1] A temblor was recorded during the early morning of this Thursday 24 September in the O'Higgins region. [1] According to the Centro de Sismología de la Universidad de Chile, the magnitude of the quake was 4.3. [1] The magnitude and intensity of a temblor are not the same. [1] The CSN describes that indistinctly a sismo, temblor or terremoto is the process of generation of elastic waves and their subsequent propagation inside the Earth. [1] Upon reaching the surface of the Earth, these waves produce movement and vibration of the ground. [1] In Chile, the term Terremoto is used for a sismo that generates structural damage, that is, one reported with Intensity on the Modified Mercalli Scale with grade VII or higher. [1] It is easy to get confused, since both concepts are related, but magnitude and intensity are not equivalent. [1] The magnitude is a measure of the size of a temblor that is related to the amount of energy released in the form of elastic waves. [1] The value is unique for each seismic event. [1] The intensity, on the other hand, measures the effects of a certain event on people, animals, structures and terrain. [1] In Chile the Modified Mercalli Intensity Scale (NCh3 of.61) is used, the intensity values are denoted with Roman numerals that classify the seismic effects with twelve levels ascending in severity. [1] The intensity not only depends on the size of the sismo (magnitude) and the force of the sismo (acceleration), but also on the epicentral distance, the local geology, the nature of the terrain and the type of constructions in the place. [1] For the same temblor, several intensities are usually reported, which in general decrease as the epicentral distance increases. [1]
A magnitude 3.8 earthquake near Hastings in New Zealand's Hawke's Bay was felt by thousands. — Source: nzherald
Colombia Tolima Swarm Continues
A magnitude 4.1 shallow earthquake hit Chaparral in Colombia's Tolima department and was felt across multiple municipalities in Tolima, Quindío, Risaralda, Valle del Cauca and Caldas. [5] Seismic activity continues to be recorded with quite frequency in Chaparral (Tolima). [5] During the night of this Wednesday 23 September, a temblor of magnitude 4.1 was reported by the Servicio Geológico Colombiano (SGC). [5] The sismo occurred at 9:34 p.m. local time and reached a magnitude of 4.1. [5] The entity indicated that it had a superficial depth, that is, less than 30 kilometers. [5] The movement adds to the string of sismos that have occurred in Chaparral during the last days. [5] Only this Wednesday, the SGC reported several events with reference to this municipality, including one of magnitude 4.5 registered at 3:09 p.m., also superficial. [5] Citizen reports located the perception of the movement in different municipalities of Tolima, Quindío, Risaralda and Valle del Cauca. [5] Among the mentioned places appear Pereira, San Antonio, Ibagué and Montenegro, in Tolima, in addition to Armenia, Quimbaya, Calarcá and Circasia, in Quindío. [5] There were also reports from Manizales, in Caldas, and Sevilla, in Valle del Cauca. [5] In the comments published together with the SGC report, some users described the movement as particularly strong. [5] “Se sintió horrible”, wrote one of the people, while another assured: “Se sintió bastante fuertecito y creo que es uno de los que más ha durado”. [5] A user pointed out: “Los estamos sintiendo todos en la parte del sur occidente colombiano… Y los que vivimos en un décimo piso, mucho más”. [5] Another comment drew attention to a historical antecedent of Chaparral and expressed concern about the recent seismic activity: “No quiero alarmarlos, pero Chaparral (el municipio original donde nació Murillo Toro) hace 200 años fue destruido por un poderoso terremoto”. [5] The entity maintains monitoring of the seismic activity in the area and requests that people who have perceived this new movement report it through the Sismo Sentido platform. [5]
New Zealand Earthquakes
A magnitude 4.9 earthquake occurred at a depth of 35 km near the Kermadec Islands, New Zealand. [2] A magnitude 3.8 earthquake struck 5 km south of Hastings near Havelock North in New Zealand's Hawke’s Bay, felt by thousands and rated as light shaking. [3] Thousands of people felt a light earthquake that struck Hawke’s Bay on Thursday night. [3] Geonet reported the quake as a 3.8 magnitude at 9.49pm, centred 5km south of Hastings, near Havelock North. [3] It classified the shaking as “light”, but there were more than 2300 reports within 10 minutes of the event. [3] The earthquake was felt across the Heretaunga Plains of Hawke's Bay. [3]
Texas Seismic Event
A magnitude 3.0 earthquake struck at a depth of 5 km, 28 km southwest of Garden City, Texas. [4] This minor event was recorded by the USGS at the specified location and depth. [4]
Understanding Magnitude and Intensity
The magnitude and intensity of a temblor are not the same according to the Chilean source definitions. [1] The CSN describes that indistinctly a sismo, temblor or terremoto is the process of generation of elastic waves and their subsequent propagation inside the Earth. [1] Upon reaching the surface of the Earth, these waves produce movement and vibration of the ground. [1] In Chile, the term Terremoto is used for a sismo that generates structural damage, that is, one reported with Intensity on the Modified Mercalli Scale with grade VII or higher. [1] It is easy to get confused, since both concepts are related, but magnitude and intensity are not equivalent. [1] The magnitude is a measure of the size of a temblor that is related to the amount of energy released in the form of elastic waves. [1] The value is unique for each seismic event. [1] The intensity, on the other hand, measures the effects of a certain event on people, animals, structures and terrain. [1] In Chile the Modified Mercalli Intensity Scale (NCh3 of.61) is used, the intensity values are denoted with Roman numerals that classify the seismic effects with twelve levels ascending in severity. [1] The intensity not only depends on the size of the sismo (magnitude) and the force of the sismo (acceleration), but also on the epicentral distance, the local geology, the nature of the terrain and the type of constructions in the place. [1] For the same temblor, several intensities are usually reported, which in general decrease as the epicentral distance increases. [1]
What to watch next: The Servicio Geológico Colombiano maintains monitoring of the seismic activity in the Chaparral area and requests reports through the Sismo Sentido platform while the USGS continues to record events such as the one near Garden City, Texas. [5] [4]
