Sea-level curve

The sea-level curve is the representation of the changes of the sea level throughout the geological history.

Comparison of two sea level reconstructions during the last 500 Myr: Exxon curve and Hallam curve. The scale of change during the last glacial/interglacial transition is indicated with a black bar.

The first such curve is the Vail curve or Exxon curve. The names of the curve refer to the fact that in 1977 a team of Exxon geologists from Esso Production Research headed by Peter Vail published a monograph[1] on global eustatic sea-level changes. Their sea-level curve was based on seismic and biostratigraphic data accumulated during petroleum exploration.[2]

The Vail curve (and the monograph itself) was the subject of debate among geologists, because it was based on undisclosed commercially confidential stratigraphic data, and hence not independently verifiable.[3] Because of this, there were later efforts to establish a sea-level curve based on non-commercial data.

In 1987–1988 a revised eustatic sea-level curve for the Mesozoic and Cenozoic eras was published, now known as the Haq sea-level curve,[4] in reference to the oceanographer Bilal Haq.[2]

Haq and Stephen Schutter published the Paleozoic sea-level curve in 2008 in Science. Subsequent revisions of the Mesozoic eustatic sea-level curve have been published by Haq for the Cretaceous, Jurassic, and Triassic, respectively in 2014, 2017, and 2018. Haq and his co-workers have now completed the sea-level history of the entire Phanerozoic Eon.