= Solution
Mark a \b[<fault scarp> cutting an <alluvial fan>] on the left-to-central smooth piedmont, approximately $(u,v)=(0.38,0.58)$. Its narrow, aligned height break continues across surfaces that are smoother than the mountains; repeated downthrow on the basin side produces the scarp. Sketch a once-continuous gently sloping fan surface cut by a basin-facing step.
Mark \b[<triangular facets>] on the mountain front in the right-central part, near $(0.78,0.48)$. These are roughly triangular planar mountain faces bounded laterally by incised valleys and below by the <fault> front. In a front view, draw repeated triangles separated by stream valleys. <Triangular facets> result from the interaction of <normal faulting>, uplift and erosion; neither they nor a sharp mountain front alone demonstrates a rupture in the particular historical event.
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