Organ Rock Formation Organ Rock Formation The Organ Rock Formation or Organ Rock Shale is a formation within the late Pennsylvanian to early Permian Cutler Group and is deposited across southeastern Utah, northwestern New Mexico, and northeastern Arizona. This formation notably outcrops around Canyonlands National Park, Natural Bridges National Monument, and Monument Valley. The age of the Organ Rock is constrained to the latter half of the Cisuralian Epoch by age dates from overlying and underlying formations. Important early terrestrial vertebrate fossils have been recovered from this formation in northern Arizona, southern Utah, and northern New Mexico. These include the iconic Permian terrestrial
Brazos Bend State Park river otter. The most noteworthy and popular residents of the park are the relatively large population of American alligators. The park is open year-round, with the exception of several weekends a year during which it is closed for controlled hunts to manage the white-tailed deer population. Brazos Bend State Park occupies land bordering the Brazos River and includes within its boundaries low-lying areas left over from the River's previous meanderings. Pre-Columbian inhabitants included a series of Native American groups, most notably the Karankawa. The land passed through a variety of landowners' hands, resulting in some of the existing structures on