The sea-level curve is the representation of the changes of the sea level

Sea level

Mean sea level is a measure of the average height of the ocean's surface ; used as a standard in reckoning land elevation...

 throughout the geological history.

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

Exxon

Exxon is a chain of gas stations as well as a brand of motor fuel and related products by ExxonMobil. From 1972 to 1999, Exxon was the corporate name of the company previously known as Standard Oil Company of New Jersey or Jersey Standard....

 geologists from Esso

Esso

Esso is an international trade name for ExxonMobil and its related companies. Pronounced , it is derived from the initials of the pre-1911 Standard Oil, and as such became the focus of much litigation and regulatory restriction in the United States. In 1972, it was largely replaced in the U.S. by...

 Production Research headed by Peter Vail

Peter Vail

Peter Vail is an American geologist and geophysicist, the namesake of the Vail curve of sea level changes. Vail earned his AB at Dartmouth College in 1952, followed by M.S. and Ph.D...

 published a monograph on global eustatic sea-level changes. Their sea-level curve was based on seismic and biostratigraphic data accumulated during petroleum

Petroleum

Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...

 exploration.

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. 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

Mesozoic

The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 and Cenozoic

Cenozoic

The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

 eras was published, now known as the Haq sea-level curve, in reference to the Pakistani-American

Pakistani American

A Pakistani American is any citizen or resident of the United States who has Pakistani heritage.- History in the United States :Muslim immigrants from areas that are now part of Pakistan have been migrating to America and first entered the United States as early as the eighteenth century, working...

 Oceanographer Bilal Haq.

See also

• Sea level change
• Past changes in sea level
• Marine terrace
  Marine terrace
  A marine terrace, coastal terrace, raised beach or perched coastline is a relatively flat, horizontal or gently inclined surface of marine origin, mostly an old abrasion platform which has been lifted out of the sphere of wave activity . Thus it lies above or under the current sea level, depending...