It is frequently in association with streams of this class that drainage areas are rearranged by the migration of divides, and that the upper waters of one river are captured by the headward growth of another.
Behind the mountain front the valleys out of which the torrents are discharged are usually short with steep side walls and a relatively flat bottom, endingheadward in an amphitheater with precipitous walls (Fig.
By lengthening headward they would work back from their mains some part, or even all of the way across the divides separating the main valleys.
It should be noted that the lengthening of a valley headward is not normally the work of the permanent stream, for the permanent stream begins some distance below the head of the valley.
It is lengthened headward by water coming in at its upper end, is widened by side wash, and deepened by the downward cutting of the water which flows along its axis.
It is manifest that if the valleys were extended headward in the direction of their axes, they would interrupt the even crest.
Less than one million years ago, during the Pleistocene Epoch of the Quaternary Period, the Prairie Dog Town Fork of the Red River began eroding headward into the Llano Estacado (Figure 6).
By headward extension toward the south, the Shenandoah finally tapped and diverted the upper waters of the smaller, less favorably situated Beaverdam Creek.
The side canyons are the result of erosion by tributaries to the main river which have gradually developed and worked headward as the main river has cut down.
On the other hand, by deploying laterally, the glacier has succeeded in capturing part of the neves formerly tributary to the ice fields to the west, and has made good some of the losses due to its headward cutting.
In its headward growth the Carbon Glacier, as one may readily observe on the map, has encroached considerably upon the summit platform of the mountain, the massive northwest portion of the crater rim of which Liberty Cap is the highest point.
It was once the cradle of a glacier, and that ice mass, gnawing headward and deploying even as the Carbon Glacier does to-day, enlarged its site into a horseshoe basin, a typical glacial cirque.
As for the skeleton character of the dividing crests, it will be readily seen to be the outcome of the headward gnawing of opposing cirques.
A glacier, accordingly, may be said, literally, to gnaw headward into the mountain.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "headward" in a variety of sentences. We hope that you will now be able to make sentences using this word. Other words: facing; forward; onward
