Rinnenkarren

   (German.) Solution grooves that form where runoff water is collected in streams. If the whole surface is moistened, the amount of water increases downwards with the result that the grooves are widened and deepened at the bottom. This distinguishes them from other similar forms. When the slope is slight they are coiled, but become straighter with increasing inclination. They are sometimes interpreted to be subcutaneous forms that develop below soil cover, but this is believed to be a rare occurrence. They are found in all climates. In arid zones, they exist as relics of the past when the climate was damper [3].