How deep are the concrete columns that support oil rigs?

Usually oil rig “legs” are steel particularly if its designed to be semi mobile. But a few concrete ones exist. Summary of Comparison between Piled Offshore Platform Structures VS Concrete Gravity Structures. For these kinds of oil rig I dont know how deep it is buried or sinks into the seabed. read more

on the earth. The oil and gas are separated at the platform and transported through pipelines or by tankers to shore. Offshore oil rig and platform types Different types of offshore oil rigs and platforms are used depending on the offshore oil/gas field water-depth and situation. read more