Slidr Sulci

Lore & Background

Slidr Sulci consists of a band of parallel ridges for much of its length, branching from a junction with Boynne Sulci. Its total length is not known; it extends from Triton's terminator in Voyager 2 imagery before terminating at a Y-junction with Boynne Sulci. The fault's cross-sectional profile varies along its length: close to the Y-junction it appears as a simple U-shaped valley, while traveling northwest a single narrow ridge appears, which forks at another fault into the plains bordering Triton's south polar cap. Within the cantaloupe terrain, ridges stand above the surrounding terrain, with a section between Hekt Cavus and Rem Maculae consisting of up to eight parallel ridges. Other sections, including one north of Tano Sulci, are located within troughs surrounded by rugged ridges. The ridges are darker than surrounding terrain by roughly 20–50%, similar to material dividing the 'cells' in the cantaloupe terrain.

The formation of Slidr Sulci is unclear. The ridge's numerous sharp bends indicate it is an extensional fault. The ridges may have been created through a sequence of eruptions of viscous cryolava in pre-existing faults and grabens, with differences in ridge structures implying a multi-stage combination of cryovolcanic and tectonic processes. Alternatively, planetary scientists Paul Schenk and M. P. A. Jackson proposed in 1993 that the ridges may represent a fold and thrust belt. Slidr Sulci crosses numerous other features, including Tano Sulci and the depression Kasyapa Cavus, which has a double-ring structure. The outer ring is incomplete, partially erased by Slidr Sulci, while the inner ring is complete, overlying the ridge, implying multiple stages of formation.

Reader's Guide

Slidr Sulci is significant as a global-scale tectonic feature on Triton, first observed by Voyager 2 in 1989, and its name was officially approved by the IAU in 1991. Its crossing of the distinctive cantaloupe terrain highlights its role in shaping Triton's surface. The fault's varied cross-sectional profile and multiple parallel ridges suggest a complex geological history, with evidence of both extensional faulting and possible cryovolcanic activity. The uncertainty in its formation—whether through cryolava eruptions in grabens or as a fold and thrust belt—underscores ongoing scientific debate. Its interaction with features like Kasyapa Cavus, where partial erasure and overlying relationships indicate multiple formation stages, provides clues to Triton's geological evolution. As one of several sulci on Triton, Slidr Sulci contributes to understanding the moon's tectonic and cryovolcanic processes, though its total length remains unknown.

Did You Know?

• Slidr Sulci is named after the River Sliðr of Norse mythology, whose waters in Hel are filled with swords.
• Slidr Sulci consists of a band of parallel ridges roughly 20 kilometers wide and up to 200 meters high.
• The ridges of Slidr Sulci are darker than surrounding terrain by roughly 20–50%.