Category: Geology

Sierra Nevada Earth Science Atlas

Published on by Jonathan Crowe
Geologic Map of the Sierra Nevada (CGS/USGS)

A collaboration between the California Geological Survey and the USGS, the Sierra Nevada Earth Science Atlas “provides the most detailed geologic framework mapping of California’s most iconic landscape to date. This web page hosts the numerous maps, data layers, and an associated report that make up the Atlas. Collectively, these layers and report show and describe the geology of the Sierra Nevada, a prominent mountain range that extends roughly north-south across eastern California and into a small portion of western Nevada, along with adjacent areas.” At the moment the Atlas consists of a geologic map plus appendices, along with a data package containing a number of map layers, with more to be added in the future.

Paleolatitude

Published on by Jonathan Crowe

Because of continental drift, the ground beneath your feet has occupied a different position on the Earth over the ages. Paleolatitude is a tool that shows the latitude of every location on earth was since the days of Pangaea. The Utrecht University news release explains why this matters:

Latitude determines the angle of the sun’s rays and thus also the local climate. Earth scientists who reconstruct the climate of the distant past from traces in rocks therefore need to know where those rocks were located at the time. And that is often not the same place as today, because the tectonic plates may have travelled considerable distances. For example, geoscientists from Utrecht are studying 245-million-year-old flora and fauna in Winterswijk (The Netherlands), which lived in an environment very similar to today’s Persian Gulf: desert and tropical sea. Is that because global climate was so much warmer back then? Or was the Netherlands situated at the same latitude as Arabia? Six years ago, they had already demonstrated that the latter was the case.

For example, according to Paleolatitude my location (45°N) has held more or less the same latitude since the Cretaceous, but in the Carboniferous it was south of the equator. PLOS One article. [Tara Calishain]

Who Gets to Digitize Colonial-Era Congolese Geological Maps?

Published on by Jonathan Crowe

Reuters: “A U.S. mining company backed by billionaires Jeff Bezos and Bill Gates is in a tangle with Belgium’s AfricaMuseum over who should digitise antique maps of what is now the Democratic Republic of Congo ‌in the museum’s archive.” The colonial-era records in question take up some 500 metres of shelving and are already being digitized under a separate project with the DRC. The AfricaMuseum says it can’t hand the records over to a private company; the mining startup, KoBold Metals, also has an agreement with the Kinshasa government to digitize the data. [Tara Calishain]

A New Map of Antarctica Suggests a Complex Landscape Under the Ice Sheet

Published on by Jonathan Crowe

A new, far more detailed map of the landscape underneath Antarctica’s ice sheet, generated “by applying the physics of ice flow to ice surface maps and incorporating geophysical ice thickness observations.” There’s an aspect of speculation, of inference, to this method—the map is predicated on our understanding of how ice flows, and that understanding may change. But in the meantime the new map is suggesting the existence of some under-ice landforms hitherto undiscovered. BBC News, Reuters.

Previously: A New Map of the Land Beneath Antarctica’s Ice.

USGS Announces New National Geologic Map

Published on by Jonathan Crowe
A screenshot of the Cooperative National Geologic Map (USGS).
USGS (screenshot)

The USGS announced a new, more detailed national geologic map last week.

The new USGS map, called The Cooperative National Geologic Map, was created using more than 100 preexisting geologic maps from various sources and is the first nationwide map to provide users with access to multiple layers of geologic data for one location. This feature allows users to access the multiple data sources included in the map to look at or beneath the surface to understand the ancient history of the nation recorded in rocks. 

Of note: the USGS cites automated processes to speed up the integration of data from its various sources (e.g., state geologic surveys), resulting in a new map after only three years of development.

Everything You Ever Wanted to Know About the 29 July 2025 M 8.8 Kamchatka Earthquake

Published on by Jonathan Crowe
A screenshot of the first slide of the USGS’s StoryMap about the July 2025 Kamchatka earthquake.
USGS (screenshot)

The USGS has posted a “geonarrative” (i.e., a StoryMap) that delves into great detail about the seismology of the magnitude 8.8 earthquake that took place on 29 July 2025 off the Kamchatka Peninsula, providing history, context and so many detailed maps about the event. [Ryan Hollister]

A New Map of the Land Beneath Antarctica’s Ice

Published on by Jonathan Crowe
An elevation map showing the topography of Antarctica underneath its ice sheet. Polar projection centred on the South Pole. Colour. From Pritchard et al., Bedmap3 updated ice bed, surface and thickness gridded datasets for Antarctica. Sci Data 12, 414 (2025).
From Pritchard et al., Bedmap3 updated ice bed, surface and thickness gridded datasets for Antarctica. Sci Data 12, 414 (2025).

The British Antarctic Society has announced the release of Bedmap3, the third and twice-as-detailed topographic model of the landscape beneath the Antarctic ice sheet.

Bedmap3, as the name suggests, is the third attempt to draw a picture of Antarctica’s rock bed that began in 2001, but this new effort represents a dramatic refinement. It includes more than double the number of previous data points (82 million), rendered on a 500 m grid spacing.

Big knowledge gaps have been filled by recent surveys in East Antarctica, including around the South Pole, along the Antarctic Peninsula and West Antarctic coastlines, and in the Transantarctic Mountains.

The outline of deep valleys is better represented. So too are those places where rocky mountains stick up through the ice. The latest satellite data have also more accurately recorded the height and shape of the ice sheet and the thickness of the floating ice shelves that push out over the ocean at the continent’s margin.

For crunchier details, see the article in Scientific Data.

Previously: Mapping Antarctica’s Bedrock.

Chinese Academy of Sciences Releases 1:2,500,000 Geologic Maps of the Moon

Published on by Jonathan Crowe
Chinese Academy of Sciences

Last month the Chinese Academy of Sciences released a set of geologic maps of the moon at 1:2,500,000 scale—twice the resolution of the USGS’s 1:5,000,000 scale maps. Available, it seems, as a geologic atlas as well as quadrangle maps—though it’s not immediately apparent from where. News: Nature, Popular Science, Universe Today.

Large-Scale Geologic Maps of Mars

Published on by Jonathan Crowe

Geologic Map of Olympus Mons Caldera, Mars (USGS)
Geologic Map of Olympus Mons Caldera, Mars. USGS SIM 3470.

The USGS’s Astrogeology Science Center highlights three geologic maps of Mars released in late 2021. The maps are large-scale, focusing on specific Martian features (e.g. Olympus Mons, above).

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.

The maps are of Olympus Mons Caldera, Athabasca Valles and Aeolis Dorsa. Interactive versions, with toggleable layers over spacecraft imagery, are also available: Olympus Mons Caldera, Athabasca Valles, Aeolis Dorsa.

Mapping the Watery Past of Mars

Published on by Jonathan Crowe

ESA

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.”

‘The People Who Draw Rocks’

Published on by Jonathan Crowe

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]

Cross-stitched Earth Science Maps

Published on by Jonathan Crowe

Kara Prior cross-stitches earth science maps; her work includes a series of state bedrock geology maps (see also Reddit) and a bathymetry map of the Great Lakes (above), among other things. She has an Etsy store.

VERITAS Mission to Map Venus Later This Decade

Published on by Jonathan Crowe

Artist's concept of the VERITAS mission to Venus (NASA/JPL-Caltech)
Artist’s concept of the VERITAS mission (NASA/JPL-Caltech).

VERITAS is one of two missions to Venus announced by NASA last week. Expected to launch between 2028 and 2030, VERITAS will produce an improved map of the Venusian surface with its two instruments: synthetic aperture radar to generate a high-resolution 3D topographic map, and a spectral emissions mapper to map rock types. News coverage: CNN, Global News, Slate, The Verge. Background from NASA; analysis from the Planetary Society.