The depression forms the northward extension of the Gulf of California, and is separated from it by the Colorado River Delta.

A number of geothermal and volcanic features are located in the area, which is a region of active seafloor spreading.

[2][3] The towns of Niland and Calipatria lie northeast and southeast of the Salton Buttes, respectively,[4] and Palm Springs is 140 kilometers (90 mi) northwest.

[6] Download coordinates as: The Salton Buttes are five lava domes[1] that rise 30–40 m (98–131 ft) above the surrounding terrain.

[22] Parts of the field have recently emerged from the Salton Sea, due to dropping water levels,[23] which have also caused the fumarolic vents to develop and grow noticeably,[24] including an increased number of gryphons.

[29][30] Since the Pliocene,[31] the Salton Trough and the Gulf of California have formed an active rift zone south of the San Andreas Fault.

[32] Since five million years ago, the buildup of sediments in the Colorado River Delta separated the Salton Trough area from the actual Gulf of California, forming a large depression that currently reaches a depth of 40 m (130 ft) below sea level.

[1] Below them, the basement is rock formed from sediments deposited in lakes and by rivers, such as mudstones, sandstones and siltstones.

[33] All of the Salton Buttes, except for Mullet Island, have developed on a lineament, a linear feature with a conspicuous magnetic anomaly.

[39] The domes are formed by rhyolite,[1] which has an alkaline and calcium-poor composition[17] and defines a potassium-rich suite (see QAPF diagram).

Scarce phenocrysts include amphibole, anorthoclase, apatite, clinopyroxene, ilmenite, magnetite, orthopyroxene, quartz and zircon.

[41] It has been found in sites in the Colorado Desert,[42] across San Diego County[43] and across northern Mexico and the Southwestern United States.

Explanations have called on several different processes, including assimilation of hydrothermally altered rocks, fractional crystallization and partial melting.

Some of these basalts resemble those from active rift zones in the Gulf of California and the East Pacific Rise.

[27] The northernmost segment of the East Pacific Rise appears to be identical to the Brawley Seismic Zone.

[44] Other proposed ages were 33,000 ± 18,000 and less than 10,000 years ago,[27] and archeomagnetic methods concluded that the Salton Buttes were not simultaneously active with Cerro Prieto or Crater Elegante in the Sierra Pinacate.

[56] These explosive eruptions deposited pumice and tephra, which were encountered in drill cores in the area, and have also been quarried.

[59] The discovery of Holocene eruptions of the Salton Buttes have drawn attention to the volcanic hazards posed by the field.

[63] The field is monitored with seismometers and periodic sampling of gas exhalations and hot springs; there is a volcano hazard map, but it is incomplete.