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Oblique air photo looking west across Upheaval Dome, with north to the right. Notice the concentric rings of the structure, and the breach in the west wall. Photo from Shelton's Earth Science slides.
Source publication
Upheaval Dome, San Juan County, Utah, is a complexly deformed circular structure approximately 5 km in diameter, occurring within the Triassic Moenkopi, Chinle, Wingate, and Kayenta and the Jurassic Navajo Formations. The structure shows three distinct zones of deformation. The brittlely deformed central crater exhibits an intensely compressional r...
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... In the very center (A1) ( Figure 4) the deformation is intense, while further out (C16) (Figures 12a and 12b) the Moenkopi is nearly flat-lying, with a few, relatively small displacement, faults. Gustavson et al. (1993) found two grains of shocked quartz within the White Rim intrusions, from a population of 10 samples thin sectioned. ...
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... the most impressive structure of this transition regime is a concentrically oriented tightly-isoclinal, slightly-overturned syncline (TISOS ) first mapped by the 1993 advanced Structural Seminar (see Figure 13b). This fold can be seen in Figure 13a, where the beds are seen dipping into the central crater (to the right) and then arching up and over themselves. ...
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... the most impressive structure of this transition regime is a concentrically oriented tightly-isoclinal, slightly-overturned syncline (TISOS ) first mapped by the 1993 advanced Structural Seminar (see Figure 13b). This fold can be seen in Figure 13a, where the beds are seen dipping into the central crater (to the right) and then arching up and over themselves. The TISOS crops out fully in only one place (on the east side, SE 1/ 4 of NW 1/ 4 B4), but it is hypothesized to have encircled the entire central crater region before erosion. ...
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... the transitional area they crop out as ramping thrust faults with a good deal of scissors motion and are often hidden in the Kayenta. In fact, these faults are most clearly located by studying air photos and observing changes in the orientation and severity of deformation of the Wingate, Kayenta and Navajo that occur in bands around Upheaval Dome (see Figure 1). For example, the band of Kayenta/Navajo in the eastern transitional area is wide, relatively flat-lying and undeformed (see Plate 2), while the band of Kayenta in the northern and southern transitional areas is narrower, much steeper and far more complexly deformed (see Plate 2). ...
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... in the southern and northern bands of the transitional regime, the Kayenta displays another kind of transitional deformation: it is extensively crumpled an a complex, often chaotic, three dimensional manner. Steeply dipping beds are common, and beds thicken, thin and fracture from intense constriction (see Figures 17 and 18). ...
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... important component of deformation throughout the transitional area is the radial folding found in the Wingate, Kayenta and Navajo. At the base of the northern Wingate crater wall, there are 6 fairly tight radial anticlines, visible in the uppermost Chinle ( Figure 16). These folds are akin to what is seen on the surface of a cloth enclosing a ball with a rubber band at its base when it is laid ball-up on a table (see Figure 19). ...
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... the base of the northern Wingate crater wall, there are 6 fairly tight radial anticlines, visible in the uppermost Chinle ( Figure 16). These folds are akin to what is seen on the surface of a cloth enclosing a ball with a rubber band at its base when it is laid ball-up on a table (see Figure 19). They have an amplitude of 10 to 15 meters, and are generally 25 to 30 meters wide. ...
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... have an amplitude of 10 to 15 meters, and are generally 25 to 30 meters wide. The uppermost Chinle bed in one of these tight radial anticlines is broken (see (Figures 21a and 21b), and in the Navajo island on the west side of the dome (see Plate 1). ...
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... Wingate is a massive, eolian sandstone, the most prominent cliff forming unit in Canyonlands, is covered with desert varnish, and full of huge crossbeds. This makes it very difficult to discern beds and faults within it (look above the Chinle anticlines in Figure 16). However, in places it is obvious that important structures are hidden within the Wingate. ...
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... has since reconsidered the size and time of the impact, hypothesizing that it occurred more recently, perhaps 50 to 100 meters above the present ground surface (Herkenhoff, p.c.). But, the outcrop which Shoemaker bases his shallow impact hypothesis on is ambiguous, and can be interpreted in a multitude of ways (the outcrop is pictured in Figures 11a and 11b). ...
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... and I mapped this outcrop as drag folds in the Chinle related to a White Rim intrusion (see Figure 11). During my work with the JPL team in January of 1995, I ...
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... of the TISOS, the Kayenta is extensively crumpled into a complex fold ring approximately 700 meters wide beginning at the crater wall. This can be seen in Figures 17 and 18. The Wingate underlying this area presumably is not deformed in the same way. ...
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... large scale, extensional, low-angle, listric normal faults found in the exterior alcoves show the convergence along these fault planes of the exterior portions of the structure toward the center. These fit both the detached salt diapir hypothesis (see Figure 31) and the impact hypothesis (see Figure 33), since both advocate convergent compression. ...
