I have studied this area in great detail, and have defined each unit based on its texture and morphology—for example, whether it is smooth, pitted, craggy, hummocky or ridged. How well a unit can be defined depends on the resolution of the images that cover it. All of the terrain in my map has been imaged at a resolution of approximately 1,050 feet (320 meters) per pixel or better, meaning textures are resolved such that I can map units in this area with relative confidence.
By studying how the boundaries between units crosscut one another, I can also determine which units overlie others, and assemble a relative chronology (or timeline) for the different units; this work is aided by crater counts for the different terrains that have been obtained by other team members. I caution that owing to the complexity of the surface of Pluto, the work I’ve shown is in its early stages, and a lot more is still to be done.
The European Space Agency has released this false-colour composite image of Ireland based on 16 radar scans by the Sentinel-1A satellite in May 2015. The colours show change over the 12 days of coverage: “The blues across the entire image represent strong changes in bodies of water or agricultural activities such as ploughing. […] Vegetated fields and forests appear in green. The reds and oranges represent unchanging features such as bare soil or possibly rocks that border the forests, as is clear on the left side of the image, along the tips of the island.” [ESA]
New Horizons mission scientists have created a geological map of a portion of Pluto’s terrain. “This map covers a portion of Pluto’s surface that measures 1,290 miles (2,070 kilometers) from top to bottom, and includes the vast nitrogen-ice plain informally named Sputnik Planum and surrounding terrain. As the key in the figure below indicates, the map is overlaid with colors that represent different geological terrains. Each terrain, or unit, is defined by its texture and morphology—smooth, pitted, craggy, hummocky or ridged, for example. How well a unit can be defined depends on the resolution of the images that cover it. All of the terrain in this map has been imaged at a resolution of approximately 1,050 feet (320 meters) per pixel or better, meaning scientists can map units with relative confidence.”
A new geologic map of Alaska has been published by the U.S. Geological Survey. From the USGS release: “This map is a completely new compilation, carrying the distinction of being the first 100 percent digital statewide geologic map of Alaska. It reflects the changes in our modern understanding of geology as it builds on the past. More than 750 references were used in creating the map, some as old as 1908 and others as new as 2015. As a digital map, it has multiple associated databases that allow creation of a variety of derivative maps and other products.” The map is available traditionally in two PDF sheets, as well as in geodatabase, Shapefile and other database formats.
As I said during the Q&A part of my fantasy maps presentation at Readercon (see previous entry), maps of other worlds in the solar system are usually images from space probes that have been set to a map projection. The key word is usually. On Monday the U.S. Geological Survey releaseda geologic map of Mars that “brings together observations and scientific findings from four orbiting spacecraft that have been acquiring data for more than 16 years.” Via io9 and Wired.
In The Geology of Game of Thrones, a group of geologists has created a geologic map of Westeros and Essos, as well as an invented geologic history of the planet on which George R. R. Martin’s epic takes place. Via io9.
This isn’t the first time a fantasy world has been looked at through a geologic lens. Karen Wynn Fonstad’s Atlas of Middle-earth took a reasonably rigorous look at the landforms of Middle-earth. And Antony Swithin—a geologist in real life under his real name, William Sarjeant—created a geologic map of his invented island of Rockall (see previous entry).
NASA has released an updated map of the bedrock beneath the Antarctic ice sheet; the map, called Bedmap2, adds considerable detail—a tighter grid and millions of data points—to its decade-old predecessor. The image above exaggerates vertical scale by a factor of 17 to increase visibility. See also this short video.