About You Are a Geologist

You Are a Geologist is a free, browser-based educational game that places you in the role of a field geologist exploring California's iconic giant sequoia groves. Walk through eight real Sierra Nevada field sites, collect geological specimens, decode the forces that shaped the landscape, and test your knowledge with science-based quizzes rooted in peer-reviewed critical zone research.

Our mission is to make earth science accessible, engaging, and scientifically rigorous for students and curious learners at every level. Too often, geology is taught through textbooks and diagrams alone. The rocks, the soils, the slow drama of a granite dome dissolving over thousands of years — these things come alive only when you encounter them in the field, or in a simulation that faithfully represents what the field looks and feels like.

You Are a Geologist brings the Sierra Nevada into the classroom, the living room, and anywhere a student has a phone or a browser. No download. No specialised hardware. Just the geology, the science, and the landscape — free to explore.

Every geological story in You Are a Geologist is grounded in real research. The game's eight field sites — Mariposa Grove, Giant Forest, Grant Grove, Redwood Mountain, Calaveras North, Nelder Grove, Mountain Home, and Alder Creek — correspond to actual field research locations in the Sierra Nevada. The geological phenomena players investigate — deep saprolite weathering profiles, glacial erratics, volcanic tephra layers, mycorrhizal weathering, bark beetle disturbance — are drawn from published critical zone science and ongoing field research conducted in these watersheds.

The critical zone is the centerpiece of the game's scientific narrative. Defined as Earth's surface layer from the top of the forest canopy to the base of fresh groundwater, the critical zone is where rock, water, air, and life interact to create and sustain soil, regulate water flow, and release the mineral nutrients on which all terrestrial ecosystems depend. Sierra Nevada sequoia groves are world-class natural laboratories for studying this zone because the trees themselves are major geological agents — their root systems fracture rock, their root chemistry accelerates mineral dissolution, and their deep water extraction reshapes moisture regimes tens of metres below the surface.

Research conducted in the Sierra Nevada sequoia groves has measured the biological weathering contribution — the mass of rock material broken down by organisms rather than by water and frost alone — at approximately 24 tonnes per square kilometre per year. This rate is roughly 12 times higher than in comparable bare rock areas at the same elevation, illustrating how profoundly life shapes the geological landscape. The giant sequoias are not merely inhabitants of their geology: they are architects of it.

Climate change is now threatening these ancient groves and the geological processes they drive. At Alder Creek Grove, prolonged drought has contributed to bark beetle outbreaks that have killed thousands of trees, reducing the biological weathering flux and slowing the soil-formation engine that took millennia to build. Understanding these dynamics requires simultaneously thinking about geology, ecology, hydrology, and climate — which is exactly the interdisciplinary perspective that You Are a Geologist is designed to cultivate.

You Are a Geologist is designed to support earth science, environmental science, and physical geography curricula at the middle school, high school, and introductory university levels. Each of the eight grove field sites is built around a distinct geological theme, allowing educators to select groves that align with the units they are currently teaching:

The in-game quiz system provides 10 field-calibrated questions per grove, covering mineral identification, weathering mechanisms, geological time, and the interplay between geology and ecology. Each answer explanation connects the question to a real-world field observation — reinforcing that geology is not an abstract classroom subject but a living science written into every landscape.

Institutional licenses are available for K–12 schools, colleges, universities, national parks, and government agencies, providing unlimited student accounts at a one-time cost. Institution purchasers may also enquire about our graduate student outreach programme, through which geology and earth science graduate researchers are available for in-person classroom visits and field trip preparation.

Giant sequoias are the largest living organisms on Earth by volume — but their significance goes far beyond their size. These trees exist at the intersection of geology, ecology, hydrology, and climate science in ways that make them uniquely valuable as a teaching subject.

The sequoia groves of the Sierra Nevada span a gradient of elevations, geologies, and climate histories, yet they share a common underlying parent material: the Sierra Nevada Batholith, one of the largest bodies of granite on Earth. This geological unity makes it possible to compare and contrast different weathering environments, different glacial histories, and different climate stresses — all against a controlled geological backdrop. For a student learning about weathering and soil formation, the sequoia groves offer an almost ideal natural classroom.

The groves are also a vivid and emotionally resonant setting. Trees that were alive during the Roman Empire and have survived dozens of ice age cycles command attention in a way that a rock sample on a laboratory bench does not. Students who engage with giant sequoias — with their scale, their age, their chemistry, their vulnerability — tend to remember the geology that explains them. That is why we chose this landscape.

We welcome questions, feedback, and collaboration proposals from students, educators, researchers, and anyone with an interest in Sierra Nevada geology or science education.

Stephen and Brooklyn Oni

YouAreAGeologist

We aim to respond to all enquiries within 2–3 business days.