Laserfiche WebLink
"Structural elements and linear features were then <br />compiled on an overlay of the 1:12,000 base map. The <br />~• length and azimuth of each feature was measured and a <br />histogram of length weighted strike frequency was <br />constructed. Major trends in the linear features were <br />identified from the histogram and each linear feature <br />represented in the major trends were replotted on <br />separate maps in format suitable for video contouring. <br />Spatial Data Systems video analysis equipment was then <br />used to construct color contour maps showing location <br />and trend of concentrations of structural features. <br />The color contour maps were finally interpreted to <br />define possible large zones of structural displacement <br /> indicated by concentrations of small features. The <br /> accuracy of the regional structural map interpreted <br /> from high altitude photography was confirmed by field <br />observations. The very strong frequency peaks evident <br />in the histograms indicate that joints, fractures, and <br />other linear features are strongly oriented in a regionally <br />persistent pattern intersecting at an acute angle of <br />70° and suggest a conjugate shear formed by compression <br />along a north 80° east trend. This trend is very <br />nearly optimum for the formation of north-northwest <br />trending folds such as those mapped in the western part <br />of the area. <br />• "The trends indicated on color contour maps appear to <br />cut across dominant topographic and lithologic outcrop <br />patterns. This trends forms fairly broad zones of <br />