Station #2: Swirls and Cracks

Activities

1)     Make both a rubbing and a sketch of the swirls from the bedrock sample.  (sample provided in the kit)  Label your results (Zoophycus- Schoharie grit worm).

 

Examples of Zoophycus trace fossil:

                           

 

                           

 

Rubbing: 

 

 

Sketch:

 

  

2) Make several observations to describe the properties of the solid bedrock you see at  this station: (other examples- Solid bedrock, Bedrock)

 

                                        

 

3)     Measure and record the acute angle (on the picture) between the joint cracks with a protractor.

                                         _______°

 

4) a) Watch the Acid Demo (here)
               *Remember-Marble is made from Limestone which is made from Calcite(CaCO3)*

               *Dolostone is made from Dolomite*

 

     b) Perform an acid test on the back of the hand sample in the kit.

 

           ____  Acid bubbled right away with lots of bubbles

            

           ____  Needed to be scratched with a nail to get it to bubble, minor bubbling

 

           ____  Never bubbled

 

 

 

5) What is the difference between a trace fossil and a body fossil?

       Trace Examples:                           Body Examples:

                                           

                                        

                                         

         

   

6) Is the fossil evidence observed at this station a trace fossil or a body fossil?

 

 

Questions - Station #2

  1) What do you think the swirls are? 

  

 

  2) How were the swirls created (starting with loose sediments and ending with solid rock  with swirls)?

  

 

  3) Compare and contrast the rocks you observed at the gravel pit by June’s Place with the rocks at this site (the creek- station 2: swirls).

  

 

4)     (a) After observing some of the rocks at the gravel pit  and the rock  here at Station 2,  do you think the sediment at the gravel pit is          transported or residual?

                  (See Definitions)                

 

            (b) Support your answer:

 

 

5)      Where is the overburden at the creek- station 2 (swirls)?

          

          Explain your answer:

 

 

  6) (a) Which site, the gravel pit at June’s Place or the swirls by the creek is older?             

             

       (b) Explain how you infer this:

  

 

 7) (a) What is the name for the long cracks in the bedrock at this site (swirls)?

         

      (b) Suggest how these cracks were formed:

  

 

  8)  View this video and use page 7 on the Earth Science Reference Tables-

 

     (a) Suggest a possible rock group, subgroup, and name for the bedrock at the creek - station 2 (example: metamorphic, foliated, gneiss):

    

     (b) Why did you choose that type (hint: look at grain size or texture)?