Abstract
A dinosaur trackway in the Middle Jurassic eolian Entrada Sandstone of southern Utah, USA, exposes three undertracks that we have modeled as isolated tectonic regimes showing the development of fold-thrust ramp systems induced by the dinosaur's feet. The faulted and folded sequence is comparable to crustal scale tectonics associated with plate tectonics and foreland fold-thrust belts. A structural analysis of the dinosaur tracks shows the timing and direction of the forces exercised on the substrate by the animal's foot during the stride. Based on the structural analysis, we establish a scenario for foot movements and weight distribution in the feet. During the end of the weight-bearing phase of the stride, the weight of the animal was transferred to the front of the digits, creating a rotated disc below the foot that was bounded by an extensional fault at the front and a thrust ramp toward the back. As the body accelerated, the foot was forced backward. The rotated disc was forced backward along a detachment fault that was bounded by lateral ramps. The interramp segment matches the width of the dinosaur's foot which created an imbricate fan thrust system that extended to the far end of the undertrack. The total length of the tectonic disturbance created by the dinosaur is up to three times that of the original footprint. Early, near-surface cementation gave the substrate the rheological properties necessary for development of the observed structures.
| Original language | English |
|---|---|
| Journal | The Palaeonology Newsletter |
| Volume | 66 |
| Pages (from-to) | 32-33 |
| Publication status | Published - 2007 |
| Event | Dinosaur tectonics - Duration: 29 Nov 2010 → … |
Conference
| Conference | Dinosaur tectonics |
|---|---|
| Period | 29/11/2010 → … |
Keywords
- Faculty of Science
- Dinosaur
- Theropod
- tectonics
- undertracks
- walking dynamics