straight rille

lunar structure

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Last updated

July 14, 2026

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A straight rille is a type of valley or trench found on the Moon. These features are typically flat-floored and relatively straight, measuring about 1–5 km wide and up to several hundred kilometers long.1

Some straight rilles are believed to be grabens, which are collapsed blocks of the lunar crust situated between parallel faults. Others appear to be tension cracks. These cracks may have formed in areas where subsurface gases caused eruptions of dark material, leading to the creation of rimless vent craters. Straight rilles are distinct from sinuous rilles, which resemble winding river valleys and are thought to be formed by ancient lava flows.1

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rille
…divided into two main types, straight rilles and sinuous rilles, which seem to have different origins. Those of the first variety are flat-floored and relatively straight; they are occasionally associated with crater chains and sometimes arranged in an echelon pattern. Some of these structures are thought to be grabens, elongated…
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…divided into two main types, straight rilles and sinuous rilles, which seem to have different origins. Those of the first variety are flat-floored and relatively straight; they are occasionally associated with crater chains and sometimes arranged in an echelon pattern. Some of these structures are thought to be grabens, elongated…
Read More