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Geologic Illustrations and Maps

Geology is one of those things that is always happening around us, but sometimes it can be difficult to imagine the processes at work. That’s why we as geologists and geoscience educators rely heavily on the use of figures, diagrams, and maps (in addition to photos of features) to describe what is going on. Figures and diagrams work great for depicting really REALLY big scale processes and features all the way down to things taking place on an atomic level. I’ve spent a lot of time creating and editing geologic illustrations and figures, this page has a small sample.

If you are interested in higher-resolution versions or want to discuss creating other figures, please get in contact!

BIG-scale processes and features

Click on the thumbnail images below for a larger version.

Block diagram illustrating the 3 main types of tectonic plate boundaries: Convergent (plates moving towards each other), Divergent (plates moving away from each other), and Transform (plates sliding laterally past each other). Also shown are features associated with convergent and divergent boundaries.
Block diagram of plate boundaries (specific to a subduction zone)
Block diagrams illustrating each individual type of plate boundary. From top to bottom: Divergent (plates spreading apart) Convergent (continent- continent) Convergent (continent- ocean) Convergent (ocean- ocean) Transform
Block diagrams of each of the types of plate boundaries. Arrows indicate direction of motion of the Earth’s lithosphere
Plate Tectonic map of the Pacific Northwest, showing the major plate boundaries and locations, as well as the major volcanoes of the Cascade Range
Plate Tectonic map of the Pacific Northwest
Cartoon-style diagram of the Rock Cycle, showing how Earth materials cycle between being igneous rocks, rock fragments (sediment), sedimentary rocks, metamorphic rocks, and melt (molten rock)
The Rock Cycle!

Smaller-scale processes and features

Below: Block diagrams of different types of faults

Block diagrams showing the 3 main types of faults- Normal faults (produced by extension; Reverse faults (produced by compression); and Strike-Slip faults (produced by shear)
Block diagrams of fault types

Below: Cartoon diagram showing how airborne lidar (LIght Detection And Ranging), a.k.a. ALSM (Airborne Laser Swath Mapping) data is collected. An airplane flies at a specified altitude, and shoots a laser at the ground underneath. An on-board computer records how long it takes the laser pulse to go from the plane, to the ground, and back- and does this at a rate of roughly 30,000 pulses per second! This can create an incredibly detailed digital topographic model of the Earth’s surface.

Cartoon showing the collection of airborne laser swath mapping data to create detailed digital topographic models
Cartoon showing collection of ALSM topographic data

Maps and other diagrams

Geologic maps are a wonderful tool that we use to display the spatial distribution of different rock types, structures, hazards, etc. at the Earth’s surface. We can use data on these maps to make inferences about what the geology is doing at depth- which is just as important to understand as the geology at the surface!

I’ve been making and using geologic maps for almost 20 years, here are a couple examples:

(1) Simplified geologic map of the central Mojave Desert, California; with balanced geologic cross-sections. From my 2015 Ph.D. dissertation (UC Davis)

Central Mojave Geologic Map and Cross-Sections

(2) My poster presentation at the 2017 Geological Society of America Cordilleran Section Meeting- much of the work was done by myself and a group of students as part of a Neotectonics class I taught at the University of Minnesota- Duluth