The Geology ground

In the 3D view, choose Geology in the ground picker (Map, Tint, Plain, Geology). The block takes the geologic map of its ground from Macrostrat, a geologic map of the world put together from published maps: each unit in its own map’s color, glaciers and permanent snow in white, the boundaries between units and the faults drawn over them. Relief, the sun and Gloss light it as they light any ground.

A spinner shows beside the numbers under the controls while the map loads, and the credit “Geology © Macrostrat (CC BY 4.0)” stays there as long as Geology is the ground.

Geo Elevation on the Mac in 3D: Mount Rainier on the Geology ground, its glaciers white and the old volcanic rocks around it in yellow, green and brown, two paths crossing the summit; the 3D controls at the top with Geology chosen and the Macrostrat credit; the Geology legend on the left, from Garda Drift and Andesite of Mount Rainier down to Glaciers and permanent snow, Lakes and rivers and Fault, with the source map, Washington Interactive Geologic Map: 1:100,000 scale, 2010; the panel with the area's numbers on the right — Mount Rainier on the Geology ground, with its legend at the top left.

The legend

The Geology card is the key to the colors:

The units on the ground, up to fourteen, grouped as geologic maps group them (sedimentary and volcanic rocks, then intrusive rocks, then metamorphic rocks) and the youngest first in each group. Each has its color, its name, and its rocks and age (“andesite flows · Quaternary”).
Glaciers and permanent snow, Not mapped (glaciers, water or ground the source map leaves blank), Lakes and rivers and Fault, when the map has them.
The source maps at the foot, with their years.

Point at the block and the unit under the pointer is marked in the legend; a long legend scrolls to it.

Choose the title to fold the card to its name, and again to open it. On the Mac and iPad it stands at the top left, across from the panel, open at first, and you can drag it out of the way. On iPhone it sits above the card, folded at first; the 3D controls, the legend and the card open one at a time there.

Where no geologic map covers the ground, the legend says “No geologic map covers this ground.” If the map could not be loaded, it says “The geologic map could not be loaded. Choose Geology again to try again.”

Geo Elevation on iPhone in 3D: Mount Rainier on the Geology ground with its two paths, the height slider at ×1.5 with Export and the chevron at the top, the Geology legend folded to its title above the card, and the card with the area's numbers: 293,260 ac, lowest 1,694 ft, highest 14,365 ft

The rock under the pointer

Hover on the Mac, or press and hold on iPhone and iPad, and the readout beside the pointer names the rock first (“Andesite flows”), then the unit and its age, then the height and the coordinates of the nearest sample.

Slope and contours

The slope bands stay off on Geology: two codes of color on one ground would mix into mud. With Slope on, the line under the controls says “No slope bands on Geology”, and the bands come back on the other grounds. Contours stay on Geology.

In the exports

Image (TIFF) and Image (PDF) show the geology as the 3D view does; the PDF’s caption carries the Macrostrat credit.
Plate (PDF) adds the explanation: the units in their groups, each with a map symbol, its color, its rocks and its age, and the source maps in the credits.
3D Model (USDZ) and Blender Scene carry the geology’s colors.

The exports draw the geologic map again at full size. If it cannot be loaded, the export stops with “Couldn’t Export” rather than make a plate without the explanation of its rocks: try again when the connection is back.

On Apple Vision Pro

In the object’s volume, the legend stands under the controls at the block’s side. Pinch the ground and the label at the pin names the rock there, and its entry in the legend is marked.

Where it comes from

The geologic map is Macrostrat’s (macrostrat.org, CC BY 4.0), made from many source maps at their own scales: the units, their names and their boundaries are the source maps’. The colors show the rocks at the surface. The unit names come as the maps give them, in English. The map is fetched for the block’s ground when you choose Geology, so it needs a connection; see Privacy.