Tuesday, February 19, 2013

Lineations on the Melt

Impact melt sheet splashed from an unnamed crater inside Joule T in the farside highlands. LROC Narrow Angle Camera (NAC) observation M184504856L, LRO orbit 12280, February 21, 2012; field of view 835 meters across, angle of incidence 37.24° at 1.44 meters resolution from 145.08 km [NASA/GSFC/Arizona State University].
Hiroyuki Sato
LROC News System

Today's Featured Image highlights a portion of an impact melt sheet that splashed from an unnamed crater about 13.5 km in diameter. 

This unnamed crater formed on the western rim of a crater nearly three times its size, Joule T (37.998 km, 27.505°N, 211.917°E).

In context mosaic below, a yellow arrow indicates a slightly darker region within the blue box, which corresponds to this impact melt sheet. The extent of this melt is about 48 square kilometers.

The narrow lineations extending from upper-left to lower-right indicate the flow direction of the melt, and likely consists of multiple flow lobes. You can also see some regions, like those near the top of the image, where flows were wider and end in round lobes. Depending on multiple factors such as the underlying slope, ejection speed, and viscosity of the melt, impact melts exhibit a wide variety of the surface patterns and morphologies. The melt here appears to have flowed at a high velocity, probably because the crater formed on the relatively steep slope of Joule T's wall.

Context view of Joule T in LROC WAC monochrome mosaic (100 m/pixel) image. The NAC footprint (blue box) and the location of opening image field of view (yellow arrow) are indicated [NASA/GSFC/Arizona State University].
Explore these fascinating impact melts in Joule T crater floor in full NAC frame yourself, HERE.

Related Posts:
Dynamics of Molten Rocks
Splash Mark
Scalelike Impact Melts
Herigonius K Impact Melt Flow
Splash and flow

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