Two interconnected estuaries protected by two small, sandy peninsulas—northern Arcata Bay and southern Humboldt Bay—lie north and west of Eureka, respectively. The color infrared film accentuates the forest areas (reds display vegetation) and shows lighter areas of clear-cutting (including redwood trees), especially toward the interior. The region’s abundant annual precipitation, logging activity, and steep slopes of the Klamath Mountains combine to create one of the highest erosion rates in the United States. South of Eureka, sediment deposits of the Eel River and one of its tributaries, the Van Duzen River, have created an extensive floodplain and fertile delta in which cultivated field patterns are visible.