One source of oxygen isotope measurements used for climate reconstruction come from:
A) air pollution.
B) cores from old trees.
C) packrat middens.
D) sea floor sediments.

Question

Quizplus · Accepted Answer

Oxygen isotope measurements can be found in sea floor sediments, which can provide information about past ocean temperatures and ice volume. This is because the ratio of oxygen isotopes in the marine environment can be influenced by changes in precipitation, temperature, and ice formation, all of which can be used to reconstruct past climates. Oxygen isotopes from air pollution, old trees, and packrat middens would not provide reliable information for climate reconstruction.

One Source of Oxygen Isotope Measurements Used for Climate Reconstruction