Chem o 7

1.

1 point

data of delta 18O and delta 13C recorded in foraminifera CaCO3 shells show that as compared to present day ocean, the glacial ocean has

lower 18O and 13C

lower 18O and higher 13 C

higher 18O and 13C

higher 18O and lower 13C

2.

1 point

delta 15N of seawater NO3 may decrease dur to increase of

N fixation

sedimentary denitrifcation

water column denitrifcation

3.

1 point

Kinetic isotope fractionation results from

The fact that molecules containing heavy isotopes move somewhat more slowly at a given temperature

The fact that molecules containing heavy isotopes move somewhat faster at a given temperature.

The fact that heavier isotopes of an element typically form slightly weaker bonds to other atoms

The fact that heavier isotopes of an element typically form slightly stronger bonds to other atoms

4.

1 point

delta 13C of foraminifera CaCO3 shells can be used as a tracer for

deep water temperature of past ocean

changes in relative size of terrestrial organic carbon pool

changes in relative size of polar ice volume

deep water phosphate content and hence ocean circulation of the past ocean

5.

1 point

Data of delta 18O recorded in foraminifera CaCO3 shells show that, as compared to the present-day ocean, the glacial ocean has:

similar salinity

higher salinity

lower salinity

6.

1 point

which of the following materials has the lowest delta 13C value

sedimentary CaCO3

organic carbon

HCO3 in seawater

CO2 in atmosphere

7.

1 point

Which of the following phenomenon is related to Rayleigh distillation

18O depletion of the foraminifera CaCO3 shells in the present-day ocean relative to the glacial period

Accumulative and progressive 18O depletion over time of clouds remnant vapor

18O depletion of the tropical surface water in the Pacific relative to the Atlantic

18O depletion of water vapor relative to tropical surface water

8.

1 point

Iso tope ratio of samples can be accurately determined using

spectrophotometer

atomic emission spectrometer

mass spectrometer

atomic absorbtion spectrometer

9.

1 point

which of the following materials has the lowest delta 13C value

sedimentary CaCO3

organic carbon

HCO3 in seawater

CO2 in atmosphere

CH4

10.

1 point

oceanic vertical profile of sea water DIC 13C is similar to

nitrate

salinity

dissolved oxygen

temperature

silicate

11.

1 point

delta 13 C recorded in foraminifera CaCO3 shells can be used to trace

ocean circulation

polar ice volume

delta 13C value of seawater DIC

pressure of water where CaCO3 was formed

conversion of C between organic carbon an oceanic DIC pools

past nutrient contend

temp of water where CaCO3 was formed

12.

1 point

the fact that stable isotope ratios can be used as tracer of temperature is based on the principle of

vital effect

equilibrium (or thermodynamic) isotope effect

kinetic isotope effect

13.

1 point

isotopes are atoms of the same element with

same protons, different neutrons

same protons, different electrons

same electrons, different neutrons

same neutrons, different protons

14.

1 point

seawater delta 18 O correlates with

temperatute

PO4

delta 13 C of DIC

salinity

15.

1 point

delta 15N of seawater NO3- may increase due to the increase of

watercolumn denitrification

N fixation

sedimentary denitrification

16.

1 point

Equilibrium isotope fractionation results from

The fact that molecules containing heavy isotopes move somewhat faster at a given temperature.

The fact that molecules containing heavy isotopes move somewhat more slowly at a given temperature

The fact that heavier isotopes of an element typically form slightly stronger bonds to other atoms

The fact that heavier isotopes of an element typically form slightly weaker bonds to other atoms

17.

1 point

18O recorded in foraminifera CaCO3 shells are controlled mainly by

temperature of water where CaCO3 was formed

seawater 18O value

polar ice volume

Pressure where CaCO3 was formed

conversion of C between organic and DIC pools

18.

1 point

delta 18O rain in high latitude regions is

similar to 18O tropical surface water

higher than 18O of tropical surface water

lower than 18O of tropical surface water

19.

1 point

bulk sedimentary delts 15N can be used to understand

N fixation

nitrate utilization in surface

watercolumn denitrification

20.

1 point

delta 18 O of foraminifera CaCO3 shells can be used as tracer for

changes in size of terrestrial organic carbon pool

deep water temp of past ocean

changes in size of polar ice volume

deep water phosphate and past circulation