Gruithuisen: Collapsed Lava Tube?

Collapsed Lava Tube near Gruithuisen
The spectacular sinuous landform shown above is thought to be a collapsed lava tube (34.7°N, 316.6°E), located near Gruithuisen K crater. NAC controlled mosaic containing images M1173350480L/R, M1173357586L/R [NASA/GSFC/Arizona State University].

This long sinuous feature extends about 48 km across Oceanus Procellarum. What is this strange feature consisting of ridges and elliptical and curved pits? Perhaps it was originally formed as a lava tube?

Caused by an eruption of basaltic lava, lava tubes form as flowing lava cools and crusts; the crust insulates the flowing lava allowing hot to flow for great distances. After some time,  perhaps due to seismic events or an impact event, lava tubes can succumb to gravitational collapse. As a consequence, a chain of pits can form along the tube. The large irregularly shaped crater-like formation at the upper left of the image is potentially the source vent for the lava flow. If there are lava tubes at Gruithuisen K, they could be as wide as 500 meters!

Because the lunar surface experiences major temperature fluctuations, cosmic radiation, and meteorite impacts, some researchers have proposed that habitats be set up inside sublunarean voids to protect people and equipment from these hazards! Check out the close-up of this spectacular landform! 

Zoomed in view of collapsed lava tube with 1km measurement
Close-up of a section of the collapsed lava tube located near Gruithuisen (34.7°N, -43.7°E). NAC controlled mosaic containing images M1173350480L/R, M1173357586L/R [NASA/GSFC/Arizona State University].

Is this feature at Gruithuisen just a chain of collapsed lava tubes? Or is there something else going on here?

There is something distinctive about the topography across the sinuous chain of pits! Drawing a profile across some parts of the feature shows a classic collapsed pit structure, a dip in elevation like a bowl with no raised rim. However, drawing across another part of the feature, in what otherwise would also appear to be a collapsed pit, appears to have a raised rim. Perhaps a levee indicative of a channelized flow...

Zoom in and out of the Gruithuisen feature below!

 

Learn more about lava tubes!

Marius Hills Pit - Lava Tube Skylight?
Tadpole and Lava Tube
Sinuous Chain of Depressions
Exploring the Lunar Subsurface

Do you want to download this image for yourself?
GRUITHSNLOD: Collapsed Lava Tube near Gruithuisen K low-Sun controlled NAC mosaic (D)

Interested in learning more about controlled mosaics? Check out Feature Mosaics: Behind the Seams

Published by Megan Henriksen on 6 October 2023