Determining the lowest point on Earth requires distinguishing between the solid lithosphere (land) and the hydrosphere (ocean). Measurement typically uses mean sea level as a reference point, though this definition is complicated when considering land covered by ice or water. The lowest points are created by immense geological forces that push or pull the Earth’s crust downward, forming depressions far below the average elevation. These extremes reveal a planet shaped by ongoing tectonic movement.
Earth’s Absolute Lowest Point
The undisputed deepest location on Earth is the Challenger Deep, a slot-shaped basin at the southern end of the Mariana Trench in the western Pacific Ocean. This oceanic abyss plunges to an estimated maximum depth of 10,935 meters below sea level, with a margin of error of about six meters. It is located within the ocean territory of the Federated States of Micronesia, about 300 kilometers southwest of Guam.
The pressure at this extreme depth is colossal, exceeding 1,089 times the pressure felt at sea level. This crushing force and lack of sunlight create a unique environment. The exact depth is measured using the geoid, a reference surface that defines the sea level baseline based on gravity and Earth’s rotation.
The deep is named after the British Royal Navy survey ship HMS Challenger, which first recorded a sounding in the area in 1875. Modern measurements confirm the Challenger Deep as the lowest point relative to sea level. The three sub-basins that comprise the Deep are formed by intense geological forces.
The Deepest Depressions on Land
When considering the lowest point on land, a distinction must be made between exposed land and continental crust covered by ice. The lowest exposed point is the shore of the Dead Sea, which borders Jordan, Israel, and Palestine. The Dead Sea surface currently sits at approximately 430 meters below sea level, making its shores the lowest land elevation on Earth.
This hypersaline lake is located within the Jordan Rift Valley. Its level has been steadily dropping due to water diversion and evaporation, falling by about one meter annually in recent decades.
While the Dead Sea is the lowest exposed point, the absolute lowest point on continental crust is concealed beneath the Antarctic ice sheet. This hidden depression is the Bentley Subglacial Trench, located in West Antarctica, which reaches a depth of about 2,555 meters below sea level. The trench is covered by thousands of meters of ice, classifying it as continental landmass. Like the Dead Sea, the Bentley Subglacial Trench is part of a massive continental rift system.
How Plate Tectonics Creates Extreme Lows
The colossal depths of both oceanic trenches and continental depressions result from plate tectonics, involving two distinct processes: subduction and rifting. Oceanic trenches, such as the Mariana Trench, form at convergent plate boundaries where two plates collide. The Pacific Plate, composed of older and denser oceanic crust, is sinking beneath the less dense Philippine Plate.
This subduction process drags the ocean floor downward, creating a deep, narrow trough. The Pacific Plate is approximately 180 million years old, meaning it has cooled and become extremely dense. This density causes it to sink steeply into the Earth’s mantle, which is why the Mariana Trench and the Challenger Deep are the deepest points in the world.
Continental depressions are typically formed by extensional tectonics, or rifting, where the Earth’s crust is pulled apart. The Jordan Rift Valley, which hosts the Dead Sea, is part of the Dead Sea Transform fault system. As the Arabian Plate and the Sinai-Palestinian sub-plate slide past each other, the crust stretches and collapses, forming a long, sunken block called a graben.
A similar extensional process created the West Antarctic Rift System, including the Bentley Subglacial Trench. Here, West Antarctica stretched and thinned, creating deep basins where the crust dropped down relative to the surrounding land. The presence of hot rock and recent magmatic activity suggests this rifting process may still be geologically active.