Seismosaurus Size Comparison
Seismosaurus 3D Viewer pairs revised Morrison figures with a 1.8 m person - length about 33 m (Size vs human uses 33 m), mass about 21-23 tonnes - so the diplodocid scale gap stays readable without discarded mega-estimates.
Seismosaurus published figures
The facts panel and this table disclose revised published figures; Size vs human uses 33 m:
| Measure | Figure | Vs a 1.8 m person |
|---|---|---|
| Length | about 33 m revised (Gillette-era 39-52 m estimates rejected after caudal reappraisal; Lucas et al. / GSA 2004); Size vs human uses 33 m | ~18.3x a person end-to-end at the 33 m scale figure |
| Standing height | about 6-8 m at the hips (proportionate estimate) | ~3.3-4.4x adult standing height at the hips |
| Weight | about 21-23 tonnes (not the old popular 100-tonne figures) | shown as a revised range, not discarded mega-mass |
| When it lived | ~155-145 million years ago (Late Jurassic), Morrison Formation, New Mexico type; herbivore; Gillette 1991; often D. hallorum | compare broader genus via Diplodocus viewer |
How the Seismosaurus size-vs-human toggle stays honest
The Seismosaurus model is drawn to a fixed on-screen length so it fits the canvas; the Size vs human control then places a 1.8 m person at the true revised length ratio used by the viewer (33 m). Tap Size vs human under the canvas to show or hide the scale figure - the comparison is proportional, not a decorative sticker. The page does not scale to discarded 39-52 m estimates.
What a person would see beside a Seismosaurus
On Seismosaurus Size Comparison, What a person would see is a Late Jurassic Morrison diplodocid - turn on the person in the viewer and orbit beside the hip or mid-body to feel how the long neck and tail sit relative to the scale figure. A license-clean CC-BY-SA 4.0 glTF may swap in after first paint; soft-tissue color remains an artistic choice if the model load fails. This model is not a fossil-accurate skeleton. For the broader genus see the Diplodocus 3D Viewer.
What the Seismosaurus size numbers are not
What these size numbers are not is an endorsement of discarded Gillette-era mega-estimates: the size comparison discloses revised about 33 m / 21-23 tonnes figures and uses 33 m only for the Size vs human scale; it does not invent soft-tissue color accuracy, and this is not a win/lose game. For the control walkthrough see how to view Seismosaurus in 3D. For trade-offs versus phone AR apps see Seismosaurus 3D viewer vs AR apps.
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