Latest news with #GaryKinsland
Yahoo
12-03-2025
- Science
- Yahoo
Scientists Found 52-Foot-Tall Underground Ripples From the Asteroid That Killed the Dinosaurs
Some 66 million years after the Chicxulub asteroid impact kickstarted the Cretaceous–Paleogene (K-T) extinction, scientists are still finding stunning evidence of its destruction. In 2021, researchers spotted 'megaripples' nearly one mile below the surface, suggesting that the megatsunami created by the impact left behind geologic formations as the waves collided with the continental shelf. Now, the authors have expanded the search and found evidence of megaripples in a 900-square-mile area throughout the Gulf of Mexico, along with their varying formations along the upper shelf and the deep sea. Of the five mass extinctions that have impacted our planet in the past 500 million years, the Cretaceous–Paleogene (K-T) extinction event certainly delivers on dramatic flair. On a spring day some 66 million years ago, a six-mile-wide asteroid smashed down just north of what is now Mexico's Yucatan Peninsula. This sudden impact created tsunamis stretching one mile tall and racing outward from the asteroid's dino-killing blow. As those waves raced toward present-day Louisiana (which was largely underwater at the time), they achieved most of their gargantuan height as they reached the ramp of the continental shelf. In 2021, using seismic data gathered by the oil and natural gas company Devon Energy, scientists led by Gary Kinsland from the University of Louisiana at Lafayette found evidence of this geologic trauma in the form of 52-foot-tall 'megaripples' located one mile underground—an area of rock associated with the end-Cretaceous period. Initially surveying a 77-mile area, Kinsland and his team determined that these subterranean ripples likely formed as the asteroid-generated megatsunamis disturbed sediment near the shore. Now, a new study from the same team reveals that these 'megaripples'—roughly spaced up to one kilometer apart—can be found both further up the shelf of what is now central Louisiana and further down in deeper waters of the Gulf of Mexico. The scientists behind this new paper found evidence of megaripples in a larger, 900-square-mile area, and explain that these formations vary depending on where the tsunami impacted sediments along the paleo-shelf. The results of the study were published in the journal Marine Geology. 'The megaripples are different on the slope, at the shelf break and further up the shelf,' Kinsland, the lead author of the new study, told Live Science. 'This is important information in modeling of tsunami, in prediction of future tsunami interactions with shelves and in the understanding of the Chicxulub tsunami.' As the study explains, the largest of these megaripples can be seen along the paleo-shelf break—the area where the Gulf's depth dramatically increases down the slope of the continental shelf toward the deep sea. The way that waves interact with the continental shelf is a well-known process known as the 'Van Dorn effect,' which describes how waves surge over a shelf. The study also discovered that megaripples further inland were more weakly asymmetric, suggesting the waves' behavior changed as they entered shallower waters. Conversely, megaripples in the deep sea took on varied shapes, likely as a result of interactions with faults and collapses, according to Live Science. 'From the coverage of the three areas here in Louisiana we infer that the buried northern Gulf of Mexico shelf system, from Texas to Florida, is covered with megaripples from at least the paleo-slope up to the paleo-bathymetry where Gulf storms would have eroded the megaripples after their formation,' the team said in a press statement. While this gives scientists a better understanding of how the Chicxulub impact tsunami affected the region, it also provides a stunningly powerful example of how tsunamis interact with continental shelves. And if our worst fears are ever realized, it may help us prepare for future asteroid encounters during Earth's never-ending journey through the universe. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
11-03-2025
- Science
- Yahoo
52-foot-high 'megaripples' from asteroid that killed the dinosaurs mapped deep beneath Louisiana in 3D
When you buy through links on our articles, Future and its syndication partners may earn a commission. "Megaripples" in the seafloor that were created in the aftermath of the dinosaur-killing asteroid impact extend much farther than scientists originally thought, new research shows. The findings offer a new insight into the extreme forces unleashed by the tsunami that followed the Chicxulub asteroid impact at the end of the Cretaceous period 66 million years ago. In the new study, published online Jan. 19 in the journal Marine Geology, researchers analyzed an extensive set of petroleum industry 3D seismic data and found that these tsunami-driven ripples extend across a far larger area than previously documented. In a 2021 study, University of Louisiana at Lafayette geoscientist Gary Kinsland and colleagues first identified a 77-square-mile (200 square kilometers) region of seismically imaged megaripples on the shelf of what is now central Louisiana. This relatively shallow part of the landmass was once submerged and extended from the coastline before dropping off into deeper ocean waters. Related: What happened when the dinosaur-killing asteroid slammed into Earth? In that 2021 study, the research team suggested that the megaripples, which have an average height of 52 feet (16 meters) and an average wavelength (from one crest of a wave to the next) of 1,970 feet (600 m), were sculpted by tsunami waves as they surged across the sediment-laden seafloor following the asteroid's impact. To build on that research, the team analyzed 900 square miles (2,400 square km) of 3D seismic data encompassing regions farther up the shelf and down into deeper waters. The results show that megaripples are present across the entire study area, revealing the widespread impact of the tsunami. However, the researchers also found significant variations in the ripples' shapes and orientations depending on their location. "The megaripples are different on the slope, at the shelf break and further up the shelf," Kinsland, who is the lead author of the new study, told Live Science in an email. "This is important information in modeling of tsunami, in prediction of future tsunami interactions with shelves and in the understanding of the Chicxulub tsunami." Near the shelf break — the point where the continental shelf suddenly drops off — for example, the megaripples are strongly asymmetric, likely due to the tsunami's surge onto the shelf. This asymmetry is what allowed Kinsland and the authors of the 2021 study to determine the direction the water was flowing when the ripples were made. The long, asymmetrical sides of the ripples slope south-southeast, pointing back to their source in the Chicxulub impact crater at the tip of Mexico's Yucatán Peninsula. About 30 miles (45 km) further inland, the megaripples are more weakly asymmetric, suggesting differences in the behavior of the tsunami as it moved into shallower waters. Meanwhile, in the deeper slope sections the team analyzed, the ripples have a much more varied shape — likely a result of the tsunami's interaction with features such as faults and collapses. The researchers propose that the megaripples were not formed in the same way as ordinary sand ripples on a beach, which develop from the movement of individual grains. Instead, they suggest that the massive earthquake following the impact fluidized a layer of sediment, which the high-speed tsunami waves then shaped into standing waveforms. "The ripples must be formed by deformation of the mass of the material," Kinsland said. "An analogy is the ripples formed in the process of making whipped cream, which produces ripples which stand after having been pushed into ripple shapes." The exact mechanism for the megaripples' formation, however, remains an open question, the authors wrote in the paper. RELATED STORIES —'This is by far the oldest': Scientists discover 3.47 billion-year-old meteorite impact crater in Australian outback —Romania's trovants: The bulbous 'living' rocks that inspired folkloric tales of dinosaur eggs and aliens —Ocean plate from time of Pangaea is now being torn apart under Iraq and Iran Understanding these ancient tsunami dynamics is not just about reconstructing the past. With modern asteroid-tracking programs in place, scientists are keenly aware of the potential for future impacts. "We track asteroids now and should be able to predict future impacts," Kinsland said. "Understanding the worldwide impact effects will help us prepare if we see one coming which we cannot deflect." With more studies underway to examine the global impact of the Chicxulub tsunami, researchers will continue to uncover new details about one of the most devastating events in Earth's history — one that reshaped both the planet's surface and the course of life itself.
