| definition | Orientation determined by fitting a plane to three or more points located on the geologic surface of interest. |
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| definition | Orientation value is specified using a calculated average of a collection of related orientations (computer generalization). |
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| definition | Orientation of a geologic structure estimated based on inspection or measurements on an air photograph. |
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| definition | Orientation of a geologic structure based on observation from a distance great enough to preclude direct inspection of the structure to determine orientation. |
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| definition | Orientation of surface or line is measured on an outcrop of that surface or line directly, e.g. by measuring a particular bedding surface, a 3-D exposure of a fold hinge, a particular stretched mineral grain in a foliation surface. | |||||
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| narrower |
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| definition | Orientation determined based on measurements from aerial photography or satellite imagery (in conjunction with an elevation model. |
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| broader |
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| definition | Orientation measured using compass or other instrument directly on or at an outcrop of the structure. | |||
| broader |
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| definition | Orientation of a surface is measured by visually averaging across one or more outcrops in a small area--e.g. approximating dip by looking down strike of beds, approximating strike by outcrop trace of one or more beds. | |||