Meet Marshosaurus, the Jurassic’s Forgotten Predator

With all the new dinosaurs being discovered these days, some of the ol’ timers are not to be forgotten. Take a look at the Marshosaurus, an ancient Jurassic predator.

I’ve spilled more than a little digital ink over the top carnivores of the Jurassic west. Allosaurus, Ceratosaurus, and Torvosaurus are all very dinosaur-y dinosaurs, checking the boxes for big, scary, and strange. But as I’ve poked around the Morrison Formation bones held at the Natural History Museum of Utah over the past few weeks, I realized I’ve done a disservice to ancient ecology by focusing on the flesh-rippers of the most imposing stature. There was an entire guild of Jurassic carnivores running around North America around 150 million years ago, and one of the least-known – at least to the public – is a mid-sized carnivore named Marshosaurus bicentesimus.


What Killed the Dinosaurs in Utah’s Giant Jurassic Death Pit?

Utah is dinosaur country—so much so that the state has a scenic byway system called the Dinosaur Diamond that connects ancient final resting places across the desert. But among the sites holding preserved tracks and dusty fossils, one boneyard stands out as a 148-million-year-old mystery: the Cleveland-Lloyd Dinosaur Quarry.


5 jurassic adventures in Utah

The original Utahns weren’t nearly as willing to bring you a casserole, but who wants to look at fossilized Relief Society presidents?


The Original Jurassic Park

Before the movie or even the book, the United States dedicated a park specifically to Jurassic dinosaurs. Dinosaur National Monument straddles the border between Colorado and Utah, a national park stuffed to the canyons with fossils from dinosaurs that roamed long ago.


Geology | Jurassic sea of sand stretched for miles and miles

Sand. Sand as far as the eye could see. Sand that stretched from central Arizona to northern Wyoming and spilled into California and Nevada. Dunes as tall as 30 feet.


MAP 236


Robert F. Biek and Mike Lowe

The Charleston quadrangle lies on the south edge of a structural and topographic saddle between the Wasatch Range and Uinta Mountains.  The quadrangle includes the southern part of Heber City and Heber Valley and the northern half of Round Valley, as well as parts of Deer Creek Reservoir and Wasatch Mountain State Park.  The quadrangle also straddles the north edge of the Charleston-Nebo thrust plate, and thus includes three distinct groups of rocks: (1) a nearly complete section of Pennsylvanian rocks of the Oquirrh Formation that comprises the Charleston thrust plate; (2) underlying, southeast-dipping Jurassic and Triassic strata below the Charleston thrust; and (3) Upper Proterozoic, Cambrian, and Mississippian strata that are exposed in a structurally complicated zone between the Charleston thrust and Deer Creek detachment faults.
A variety of late Tertiary and Quaternary deposits record the evolution of the present landscape.

This geologic map and report provide basic geologic information necessary to further evaluate geologic hazards and resources in the area, and to gain an understanding of the geology upon which this landscape developed.

CD (28 p., 2 pl., 1:24,000)