Chemostratigraphy Flashcards
(2 cards)
1
Q
What are varying Sr/Ca data due to?
-what is it due to globally?
-what is it due to short term?
A
Thought to be due to varying Sr/Ca ratios in sea water similar to Aragonite vs Calcite and hydrothermal activity
- globally increased Sr/Ca ratios due to decrease in submarine hydrothermal activity
- short term fluctuations caused by sequences of transgression and regression
2
Q
Where are O18 and O16 stable isotopes generally concentrated?
A
Usually a good ratio of O18 and O16 in sea water and O16 in rainwater and fresh water but when oxygen gets locked up (in ice), the ocean gets depleted in O16 and enriched in O18.
