Indeed, the interpolated representation of the base Sundance is somewhat higher (∼40 m) than the representation by projecting the top Tensleep Sandstone surface up section in the vicinity of the fold crest on sections C‐C′ and D‐D′, but considering the lack of data in the fold hinge and the uncertainty of any surface model at SMA, this difference is relatively small. In this region and beyond the forelimb syncline, the ALSM constrained MCS model could be improved by adding data points that estimate the surface geometry. [17] The Phosphoria Formation is the youngest unit in the Paleozoic section, and the youngest unit on the prominent topographic expression of the fold. Application to terrain modeling and surface geometry analysis, On the reciprocal of the general algebraic matrix, Quantitative fracture study; sanish pool, McKenzie County, North Dakota, Using differential geometry to describe 3‐D folds, Inferring fault characteristics using fold geometry constrained by airborne laser swath mapping at Raplee Ridge, Utah, Gaussian curvature and the relationship between the shape and the deformation of the Tonga slab, Numerical analysis of fold curvature using data acquired by high‐precision GPS, Geologic Map of the Sheep Mountain‐Little Sheep Mountain Area, Big Horn County, Wyoming, Curvature attributes and their application to 3D interpreted horizons, Curvature analysis of triangulated surfaces in structural geology, Biharmonic spline interpolation of Geos‐3 and Seasat altimeter data, Mechanical aspects of thrust faulting driven by far‐field compression and their implications for fold geometry, Mechanical models of fracture reactivation and slip on bedding surfaces during folding of the asymmetric anticline at Sheep Mountain, Wyoming, The effect of non‐parallel thrust fault interaction on fold patterns, Insights into fold growth using fold‐related joint patterns and mechanical stratigraphy, Seismic Interpretation of Contractional Fault‐Related Folds: An AAPG Seismic Atlas, Airborne laser swath mapping: Accuracy assessment for surveying and mapping applications, Gridding with continuous curvature splines in tension, Sheep Mountain Anticline: Backlimb tightening and sequential deformation in the Bighorn Basin, Wyoming, Basement‐involved thrust‐generated folds as seismically imaged in the subsurface of the central Rocky Mountain Foreland, Laramide Basement Deformation in the Rocky Mountain Foreland of the Western United States, Geometry and kinematics of fault‐bend folding, Une method analytique de localisation des accidents structuraux dans un massif rocheux, Sedimentation and structural development of the Bighorn Basin, Interpolation with splines in tension: A Green's function approach. Geologic map of the Sheep Mountain--Little Sheep Mountain area, Big Horn County, Wyoming / U.S. Department of the Interior, U.S. Geological Survey ; by Robert L. Rioux. Sources include the clay and gypsum dunes in the Bighorn Basin, as well as exposed gypsum in the Sheep Mountain anticline to the southwest, on the slopes of the Pryor Mountains to the northwest, and in the Cody area on the west side of the Bighorn Basin (Reheis 1987). These mountains, in turn, are part of a structural province extending from Canada to New Mexico. To calculate the weights of the Green's functions for each of these data sets requires calculating the SVD for matrices of 23,049 × 23,049, 7612 × 7612, and 2188 × 2188, respectively. We acknowledge that multilayer folding to nearly vertical limb dips is a more complex physical process than the small deflection of a single elastic layer. Also, because outcrops are inaccessible, strike and dip measurements were not obtained on most of these surfaces. Find this Pin and more on UM formations by Dennis Cox. The numerical interpolation algorithm used here would be considered an arbitrary choice in such cases. Kaven et al. We see that for both strike and dip, there are large differences between calculated and measured orientations for small outcrops. However, geomechanical models by Sanz et al. Projection of data points above or below the base Sundance Formation would have been subject to error similar to the projection error in this study. Greater differences for smaller outcrops occur because bedding orientation cannot be accurately determined from the limited ALSM data. The Fold Analysis Challenge: A virtual globe-based educational resource. [1996] (Figure 11c) and therefore enables a direct comparison to the model generated by sequential cross sections. The rocks underfoot record the evolution of Wyoming geology over 3.8 billion years. Structural Geology: A Quantitative Introduction. and you may need to create a new Wiley Online Library account. It resulted from down cutting of the land surface by rivers and streams and the removal of much of the original basin fill sediment. No slope constraints were discarded in regions with broad ALSM constraint. The Gypsum Springs Formation is the youngest resistant, outcrop‐forming unit exposed in the forelimb study area. (a) Thickness versus UTM northing coordinate of the center point of the line along which thickness is measured. Error bars account for the range of observed dip values in the vicinity of each measurement and for error in zab, which results from ALSM imprecision and, more important, outcrop weathering as observed in the field. (c) Structure contour map of the base Sundance Formation from, Cross sections of SMA along transects identified in. google_color_border = "FFFFFF"; The lead, narrating the way through Sheep Mountain fold analysis Challenge: virtual... 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