At the top of the grand staircase. The late cretaceous of Southern Utah / На вершине Великой лестницы. Поздний меловой период Южной Юты

Southern Utah possesses a wild, stark, rugged landscape that leaves most people who experience it irrevocably and profoundly changed. Scenic wonders such as the Grand Canyon, Bryce Canyon (Fig. 1.1), Zion Canyon, The Wave, Buckskin Gulch, Cedar Breaks, and Capitol Reef are deservedly visited annually by millions of tourists from all over the globe who leave both awestruck and humbled. What is true for the tourist is even more so for the geologists and paleontologists who have worked in the canyon, mesa, plateau, and cliff outcrops of the Grand Staircase–Kaiparowits Plateau region ever since the fi rst reports of the Powell expedition were published (e.g., Dutton, 1880; Howell, 1875). But the bedrock geology of the Grand Staircase provides not just the raw material for geomorphological agents to shape renowned scenic wonders; it also contains the fascinating saga of the evolving North American Cordilleran biosphere: a cavalcade of changing landscapes and organisms frozen in time for researchers to poke, prod, and ponder. Even though the area was fi rst geologically mapped over 125 years ago, many basic stratigraphic and paleontological questions still remain unanswered. For vertebrate paleontologists, the region is still a frontier waiting to yield a wealth of data on the Mesozoic biosphere. <...>