The Student Room Group

OCR geology unit 5 2016

Scroll to see replies

Original post by Pablo Picasso
Carbo and Pyrit, not sure if Pyrit would be acceptabke?


Pyrite could work because it's a form of replacement in an anoxic environment which preserved graptolites are found in.
Original post by Vikingninja
I Remember in the textbook that it says graptolites can be preserved by carbonisation. We were never taught what it's exact composition was.


Yeah I can't remember that one.

With the two brachiopods did you put the mode of life for both was benthonic, epifaunal sessile?


I put the pedicle one as epifaunal, and the second as infaunal. Pretty sure i got the infaunal one wrong
Original post by Pablo Picasso
It's always carbonisation


they cant be preserved below the CCD if it's by carbonisation.... there's literally no carbon in them which is kinda necessary for carbonisation lol
Original post by Vikingninja
Pyrite could work because it's a form of replacement in an anoxic environment which preserved graptolites are found in.


Yes easy marks there
did anyone else get the greatest sense of relief handing their textbooks back in anyway
Original post by savingwonderland
they cant be preserved below the CCD if it's by carbonisation.... there's literally no carbon in them which is kinda necessary for carbonisation lol


Graptolites is the most commonly found preserved due to carbonisation, i'm sure
Original post by savingwonderland
yea i got replacement and pyritisation cause they're preserved below CCD so no carbon


That's calcite compensation depth.

Original post by savingwonderland
Yep but for the first i put attached by the pedicle and the second i said free lying with spines to spread weight

Yeah I put the same but spines acted as anchors.
Original post by Vikingninja
That's calcite compensation depth.


Yeah I put the same but spines acted as anchors.


Nooooo noo its 10000% carbonate compensation depth google it, its ingrained in my brain from how many times my teacher covered it last year and this year. Anyways im logging off my brain is 110% done with geology forever, good luck with results folks you sound like you did better than the vast majority of my class so you've got little to worry about :smile:
Original post by savingwonderland
did anyone else get the greatest sense of relief handing their textbooks back in anyway


I bought mine.
Original post by savingwonderland
Nooooo noo its 10000% carbonate compensation depth google it, its ingrained in my brain from how many times my teacher covered it last year and this year. Anyways im logging off my brain is 110% done with geology forever, good luck with results folks you sound like you did better than the vast majority of my class so you've got little to worry about :smile:

Yeah calcite is a carbonate but schleroprotein isn't (got full name wrong). Good luck with yours as well.
Original post by Vikingninja
Yeah calcite is a carbonate but schleroprotein isn't (got full name wrong). Good luck with yours as well.


The 4 marker on adv of biostrata to litho for fossilerferous linestone, what did you put down :smile:
Original post by Pablo Picasso
The 4 marker on adv of biostrata to litho for fossilerferous linestone, what did you put down :smile:


Pretty sure that was 2 marks. I put that litho could correlate beds of different ages if two different beds appear the same in different areas. Then put about the large amount of fossils which could be used to correlate beds. Think the second part I put was mediocre, probably wanted this fully: large amount of fossils will have varying ranges and if a bed contains several fossil types then can be correlates to another with all those (since it didn't state any zone fossils).
Original post by Vikingninja
Pretty sure that was 2 marks. I put that litho could correlate beds of different ages if two different beds appear the same in different areas. Then put about the large amount of fossils which could be used to correlate beds. Think the second part I put was mediocre, probably wanted this fully: large amount of fossils will have varying ranges and if a bed contains several fossil types then can be correlates to another with all those (since it didn't state any zone fossils).

I talked about diopachronus beds causing problems :/
Original post by Pablo Picasso
I talked about diopachronus beds causing problems :/


Yeah that would be another good one. The question didn't state rock type, only that a sequence is fossiliferous so could be any rocks with lots of fossils.
Original post by Vikingninja
Yeah that would be another good one. The question didn't state rock type, only that a sequence is fossiliferous so could be any rocks with lots of fossils.


So what do you think the GBs will be? Last year it was 70/100 for an A
Original post by Pablo Picasso
So what do you think the GBs will be? Last year it was 70/100 for an A


I feel like it will be around 73 for an A. Mostly decent questions, 6 and 8 were the nasty ones. I think that the unit 4 will be quite low.
Original post by Vikingninja
I feel like it will be around 73 for an A. Mostly decent questions, 6 and 8 were the nasty ones. I think that the unit 4 will be quite low.


I hope mate :/
What was the function of the tabula

The question on trace fossil, and it asked about 2 sedimentary additional observations to infer environemental something like
Were i on the right track talking about grain size and cross cutting relationship?
Original post by Pablo Picasso
I hope mate :/
What was the function of the tabula

The question on trace fossil, and it asked about 2 sedimentary additional observations to infer environemental something like
Were i on the right track talking about grain size and cross cutting relationship?


They strengthen the corallite, don't remember a question their function. Only that one asking what species had them.

Grain yes since it shows energy levels. Don't think so for cross cutting since that tends to be for stuff like igneous intrusions and faults which aren't due to deposition.
Original post by savingwonderland
did anyone else get the greatest sense of relief handing their textbooks back in anyway

yesss! i probably read it all 50 times!
what did people shade and circle on the question that asked for one interambulacral plate, i shaded one whole strip then changed my mind and did a singular plate on one of the strips?

Quick Reply

Latest