Sea-level record of the past million years

Lecture 18

This record of d18O is from planktonic forams from a core in the sub-tropical Atlantic ocean.

It is a record of temperature and ice volume for the past 130,000 years or so.

A longer record from a core in the Equatorial Pacific ocean.These are divided into time-rock (chronostratigraphic) units,

the Marine Oxygen Isotope stages

A tabulation of the Marine Oxygen Isotope ages

The cyclic filling and drawing down of the world oceans has a profound effect on processes and history along coastlines.

Let’s revisit the littoral clastic record, and then we’ll turn to the record of fringing coral reefs

An example from Half Moon Bay, central California

Mahia peninsula, North Island, New Zealand

Pasadena

Palos Verdes peninsula

Fringing reef terraces

Ages by alpha-particle counting, ~1968, at Columbia University

Ages by thermal ionization mass spectrometry, ~1988, here at Caltech