Though maps have historically covered large areas, with crewed lunar missions on the horizon and other missions across the solar system in the planning stages, large-scale, small-area maps are starting to steal the limelight. These large-scale, small-area maps provide highly detailed views of the surface and allow scientists to investigate complex geologic relationships both on and beneath the surface. These types of maps are useful for both planning for and then conducting landed missions.
A new map of Mars reveals the abundance of aqueous minerals—clays and salts that form in the presence of water—that were created during the planet’s distant watery past. “The big surprise is the prevalence of these minerals. Ten years ago, planetary scientists knew of around 1000 outcrops on Mars. This made them interesting as geological oddities. However, the new map has reversed the situation, revealing hundreds of thousands of such areas in the oldest parts of the planet.”
Melting glaciers are keeping a special team of cartographers at Swisstopo, Switzerland’s national mapping agency, busy: they’re the ones charged with making changes to the Swiss alps on Swisstopo’s maps. The New York Times reports:
“The glaciers are melting, and I have more work to do,” as Adrian Dähler, part of that special group, put it.
Dähler is one of only three cartographers at the agency—the Federal Office of Topography, or Swisstopo—allowed to tinker with the Swiss Alps, the centerpiece of the country’s map. Known around the office as “felsiers,” a Swiss-German nickname that loosely translates as “the people who draw rocks,” Dähler, along with Jürg Gilgen and Markus Heger, are experts in shaded relief, a technique for illustrating a mountain (and any of its glaciers) so that it appears three-dimensional. Their skills and creativity also help them capture consequences of the thawing permafrost, like landslides, shifting crevasses and new lakes.
The article is a fascinating look at an extraordinarily exacting aspect of cartography. [WMS]
It shows the movement of Earth’s tectonic plates over the past billion years, and it was posted by one of the co-authors of this study proposing a new, single model of plate tectonic activity that covers the past billion years of Earth’s existence. (Previous models, if I understand the abstract correctly, covered shorter periods—for several-hundred-million-year values of short—and didn’t line up with each other.)
Out last month from Princeton Architectural Press: A Slice Through America: A Geological Atlas by David Kassel. This is a history of stratigraphic illustrations, which Kassel has been collecting for decades. “Historic stratigraphic illustrations depict the earth beneath our feet in captivating hand-drawn diagrams. Each drawing tells a unique geologic story, exquisitely rendered in colors from pastel palettes to brilliant bolds that show evolving scientific graphic conventions over time. Created by federal and state geologists over the course of one hundred years, the maps reveal sedimentary rock layers that present an unexpected view of our treasured public lands, making this collection an important record of natural resources, as well as a beautiful display of map design.” Amazon (Canada, UK), Bookshop.
Two geological maps of Venus have been published in Earth and Space Science. Produced by Vicki L. Hansen and Iván López, they each cover a 60-million-square-kilometre section of Earth’s twin: the Niobe Planitia Map Area geologic map (above, top) ranges from the equator to 57° north, and from 60° to 180° east longitude; the geologic map of the Aphrodite Map Area (above, bottom) is the Niobe Map Area’s southern hemisphere equivalent, covering the area from 60° to 180° east longitude, but from the equator to 57° south.
Zealandia (Te Riu-a-Māui) is the name given to a proposed, and largely submerged eighth continent, of which New Zealand (Aotearoa) is the largest above-water remnant. Explore Zealandia is geoscience company GNS Science’s web portal to their maps of this largely submerged continent, including bathymetry, tectonics, and other data; the data is also available for download. [WAML]
A new unified geologic map of the Moon, based on digital renovations that updated 1970s-era geologic maps to match more recent topographic and image data gathered by lunar orbiters, was released by the USGS last month. The map is “a seamless, globally consistent, 1:5,000,000-scale geologic map”; the paper version (25 MB JPEG) provides azimuthal projections beyond the 55th parallels and an equirectangular projection between the 57th parallels. [Geography Realm]
The map legend colors represent the broad types of geologic units found on Titan: plains (broad, relatively flat regions), labyrinth (tectonically disrupted regions often containing fluvial channels), hummocky (hilly, with some mountains), dunes (mostly linear dunes, produced by winds in Titan’s atmosphere), craters (formed by impacts) and lakes (regions now or previously filled with liquid methane or ethane). Titan is the only planetary body in our solar system other than Earth known to have stable liquid on its surface—methane and ethane.