Use the worksheet above to answer the following questions. _____ 1. Which layer in the diagram below contains the most organic material? 1. A 2. B 3. C 4. the bedrock _____ 2. How is soil created from rock? 1. physical weathering without chemical weathering 2. chemical weathering without physical weathering 3. erosion 4. both chemical and physical weathering _____ 3. Approximately how many years does one centimeter of topsoil take to form? 1. 100 – 400 years 3. 1000 – 4000 years 2. 10 – 40 years 4. 10,000 – 40,000 years _____ 4. Which of the following is found in the greatest % in soil? 1. Mineral matter 2. Organic matter 3. Water 4. Air _____ 5. Which layer of a soil profile forms first from the bedrock? 1. A horizon 2. B horizon 3. C horizon 4. Humus _____6. The cross section below shows layers of soil Which 2 processes produce the layer of dark brown to black soil? 1. Erosion and uplift 3. Compaction and cementation 2. Melting and solidification of lava 4. Weathering and biological activity
______ 7. The mineral composition of a residual soil is most affected by the 1. Depth of the water table 3. Type of bedrock material 2. Elevation of the surface 4. Steepness of hill slopes _______8. What factors most directly control the development of soils? 1. Earthquake intensity and volcanic activity 2. Direction of prevailing winds and storm tracks 3. Bedrock composition and climate characteristics 4. Soil particle sizes and method of deposition 9. For the soil profiles below, label the horizons (A, B, or C) and the parent material in each of the soil profiles using the spaces provided next to each image. ______ ______ ______