OBJECTIVES

Chapter 6  Weathering, Soils and Sedimentary rocks

1.  Explain the difference between physical (mechanical) and chemical weathering.

2.  Understand each of the following types of mechanical weathering

      a.  frost wedging

      b.  crystal growth

      c.  plants, animals and humans (organic activity)

      d.  abrasion

      e.  unloading/exfoliation/sheeting

      f.  thermal expansion and contraction (insulation)

3.   Understand the relation between physical and chemical weathering and the importance of surface to volume ratio in chemical weathering.

4.   Describe each of the following forms of chemical weathering.

      a.  dissolution (i.e., NaCl)                                                            

      b.  hydrolysis

      c.  oxidation

5.   What factors can increase the acid content of surface water on earth?                     

6.   Know, comparatively which minerals weather away quickest and which last the longest.

7.   Describe the relative importance of both physical and chemical weathering in each of the following environments:

      a.  arctic and alpine regions                                               c.  desert  regions

      b.  temperate mid‑latitudes                                               d.  humid tropics

8.   Understand what is meant by the term soil horizons and explain how soil changes with       

environment:

9.   Describe how each of the following factors influence the weathering of rock and formation of soil:

      a.  rock composition (parent material)

      b.  plants and animals

      c.  climate

      d.  slope

e.   time

f.   porosity of parent rock

10.  Terms to know:

      a.  humus                                                                         e.  spheroidal weathering

b. sheeting                                                                        f.  talus slope      

      c.  soil                                                                              g.  Fracture/joint 

      d. regolith                                                                        h differential weathering              

11. Describe the process of lithification of clastic (detrital) sedimentary rocks and list in order of abundance the three commonest glues to form clastic sedimentary rock.

12.  Differentiate between clastic (detrital) sedimentary and chemical (non-clastic) sedimentary rocks and give examples of each.

13.  Give the environments that form each of the following sedimentary rocks:

shale, mudstone, siltstone                conglomerate

sandstone breccia

14.  Differentiate between chemical and physical maturity and be able to use the following terms:

a.   graded vs non-graded

b.   well sorted vs poorly sorted

c.   angular vs rounded clasts

15.  Differentiate between and give examples of rocks of inorganic and biogenic (biochemical) origin.

16. Differentiate between the composition and origin of the following chemical rocks:

limestone chert

travertine                                        coal                                                                             

17.  Describe the origin of coal and differentiate between:

peat                                                            bituminous

lignite                                                          anthracite

18.  Define the term Asedimentary facies@ and describe transgressions and regressions and the deposits they create. (201 students)

19.  What is “bedding” in sedimentary rocks and explain how cross bedding forms and what graded bedding is.

20.  How can different types of ripple marks preserved in sediment be use to explain the history of an area?

21.  Be able to list three different reasons as to why sedimentary rocks are important