1. Please take out module 25 for check-off! Get a computer
APES 12.3 and 12.4
Please take out module 25 for check-off!
Get a computer

2. Module 25 Multiple Choice
D- acid rain only causes chemical weathering. Erosion is a natural process
E- main soil formation factors are climate, parent material, topography, organisms, time
D- correct horizon order is OAEBC
A- clay isn’t as permeable and won’t allow as much water to seep out
E- aluminum would lower the base saturation because (Al and H are the main soil acids)
E- tailings are the waste materials from mining

3. End of Chapter MC
D- heavier elements make up the earth’s core and lighter elements are towards the surface
C- after the core, the order of layers is mantle, asthenosphere, lithosphere, soil
E- all 3 are evidence of Pangaea
E- subsurface mining is most dangerous to miners because of build up of toxic gases and chance for collapses
E- each step up the richter scale is 10x more powerful (like the pH scale!)

4. End of Chapter MC
6. D- plate move laterally at transform plate boundaries 7. C- subduction occurs at convergent boundaries 8. B- seafloor spreading occurs at divergent boundaries 9. E- an epicenter is the point above an earthquake 10. E- fossils are found in sedimentary rock 11. C- extrusive igneous rock comes from cooling of magma, so it must be on the ocean floor where magma comes up (best answer) 12. A- soil DOES change constantly 13. C- the B horizon is subsoil

5. Homework Accuracy Check
Module 24:
From #19: what are some unique characteristics of igneous rock?
Module 25:
b. Write down your answer to #7
c. Define two different mining methods

6. Finish Rock Cycle Notes

7. Soil Formation and Properties

8. Soil Formation
The type of soil found in an ecosystem is determined by:
Parent material (underlying rock)
Climate (affects amount of decomp., types of vegetation)
Topography (losing/gaining sediment from erosion)
Organisms (decomposers, detritivores, etc.)
Time (usually more time = more nutrients)

9. Soil Formation

10. Soil’s profile is made up of several distinct horizontal layers called Horizons

11. O Horizon – “Organic” Layer, contains dead/decomposing plants & animals; supplies nutrients for the soil
A & E Horizon – Topsoil (darker brown); where majority of roots located, thickness dependent on amount of decomposed material
B Horizon – Subsoil (Lighter/Cinnamon) ; materials from A & O deposited, few roots
C Horizon – Parent material (gray); weathering of this horizon creates upper horizons

12. Leaching and Accumulation
ion/collections/soil_horizons.html
From the top  Decomposition and the leaching of water through the soil move nutrients
From the bottom  Weathering causes the parent material to break apart

13. Soil Profile O
Eluviation/Zone of Leaching – water percolates down the soil, transporting materials. Happens in Horizons A & E A E
Illuviation/Zone of Accumulation – where transported materials are deposited. Happens in Horizon B. B C

14. Soil Analysis Lab
Which soil horizon will you be testing?

15. Soil Texture Find 40% Sand 45% Silt 15% Clay Loam Mixture of all 3
Really only need to find 2 of the 3 points. 3rd point acts as a clarifier
Sandy loam would be a mixture of all 3, that has a significantly higher percentage of sand

16. Soil Lab Steps Read introduction and do pre-lab q’s
Lab 1- Soil Texture
a.(do the quantitative “feel” test and the
quantitative soil triangle test)
b. Answer the analysis q’s as homework!
3. Lab 2- Soil Porosity (percent pore space)
Read the background and examine the rock samples first
Do the porosity procedure and calculation (see formula in the background)

17. Soil Lab Steps Lab 3- Soil Percolation
Read the background and answer the pre- lab questions
Do the test using your phone for a timer
Lab 4- Soil pH
Use the pH probes instead of test strips

18. Eastern WA soil is more suited for farming than Western WA. Why?
No glaciers  sandy soil that weathers easily
Hotter  Speeds up decomposition
Less dense canopy  more water hits soil and soaks in
Grasslands  Easily decompose
Western WA
Glaciers  Gravel and silt
Colder  Slower decomposition
Dense canopy  A lot of rain caught in trees
Conifers  Needles very acidic and don’t decompose

19. Due Next Time ALL of Soil Lab!
(Pre-lab, data, analysis questions all in lab book!)