Receding Lake Powell reveals ‘extraordinarily uncommon’ fossils
3 min read
The receding waters of Lake Powell have revealed some extraordinarily uncommon fossils from the Jurassic interval.
Paleontologists had been documenting fossil tracks at Glen Canyon Nationwide Recreation Space in Utah once they discovered a bone mattress containing fossils of trichomes — extinct mammal-like reptiles that lived 180 million years in the past.
The fossils, which embrace bones and tooth, are extraordinarily uncommon and are the primary triploid bone mattress to be present in Utah’s Navajo Sandstone, a geological formation in Glen Canyon, the Nationwide Park Service reported.
These fossils are among the most essential found in the US this yr — not solely as a result of they offer researchers perception into the species, however as a result of they make clear the historical past of Lake Powell’s altering shores.
Beforehand submerged, Lake Powell has seen water ranges drop in recent times resulting from a protracted drought within the space.
Paleontologists discovered the fossils in March. They simply occurred to be within the “proper place on the proper time,” earlier than a file quantity of snowmelt flooded the lake, making it not possible to entry, the NPS mentioned. Lake Powell is replenished seasonally by melting snow flowing from the encompassing mountains by way of the Colorado River. Whereas river flows have remained low for a few years, this yr noticed a file quantity of snowmelt that accrued throughout a very moist winter.
Because of this paleontologists had a really brief time to recuperate the fossils earlier than they had been utterly submerged once more.
“Learning these fossils will assist paleontologists be taught extra about how early mammalian relations survived the mass extinction on the finish of the Triassic and diversified in the course of the Jurassic,” NPS mentioned.
A number of hundred kilos of rock containing the fossils had been faraway from the location and transported to laboratories for additional analysis.
The fossils will develop into a part of the Glen Canyon NRA Museum assortment that might be housed on the Prehistoric Museum in Worth, Utah.
Lake Powell is surrounded by large geological formations containing many unearthed fossils.

Brian Eng/NPS
“Essentially the most well-known and ample fossils identified from the Glen Canyon NRA are the footprints of carnivorous dinosaurs within the Glen Canyon group,” the NPS mentioned in an announcement. “This sequence of sedimentary rocks, named after their publicity alongside the valley itself, was shaped by rivers, lakes, streams and deserts from the Late Triassic by way of the Early Jurassic. One of many largest mass extinctions in Earth’s historical past occurred throughout this era.”
Whereas drought within the southwestern United States raises many considerations about water shortages, declining water ranges in some reservoirs and lakes have revealed some attention-grabbing findings.
Low water ranges in close by Lake Mead, situated in Nevada and Arizona, have revealed a lot of shipwrecks and artifacts.
This has additionally occurred in different areas of the US experiencing drought circumstances.
Dinosaur footprints relationship again hundreds of thousands of years had been uncovered amid a extreme drought in Texas final yr.
The footprints had been found at Dinosaur Valley State Park in Glen Rose when water ranges within the Paluxy River dropped amid excessive temperatures.
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