1. DISCOVERY

The team found fossils on a prior trip to the Irhazer Plain,

preserving them from erosion with a plaster cap. In 2022,

they returned to excavate the mysterious animals.

2. MAPPING WITH PHOTOS

Hundreds of photos from drones and handheld

cameras recorded the excavation’s progress.

Anchor points common to the images allowed

photogrammetry software to connect them.

3. EXCAVATION

The team carefully brushed and chipped away

rock and dirt surrounding fossils, using hand and

power tools. Fossil measurements and positioning

data could be gleaned from the digital models.

4. FOSSIL PREPARATION

Fossils freed from most of their surrounding

rock were wrapped in casts, called jackets.

Wooden braces helped protect brittle or

fractured fossils during transport.

5. FOSSIL MODELING

Photogrammetry also let the team make 3D models

of individual fossils for virtual study—and to envision

how an animal might have looked.

Graphic: Fernando G. Baptista, Patricia Healy, and Lucas Petrin, NGM Staff.

3D renders by Daniel Vidal. Sources: Paul Sereno, University of Chicago;

Daniel Vidal, UNED & University of Chicago

MAPPING DINOS

IN THE DESERT

For decades, the standard means of

documenting a dig site required

patient field drawing and laborious

measurement. Now photogramm-

etry can accomplish in minutes what

otherwise takes days (and in 3D).

DIGITAL SITE MODELING

In Niger, Sereno and his team relied

on tools that stitch together photos

to make spatially accurate 3D site

models. Less manual mapping

meant more time for digging.

TRADITIONAL SITE MAPPING

Paleontologists set up a grid to

plot fossil locations, measuring

and drawing by hand. But an

artist’s angle of view is limited,

and the method is time-

consuming and less detailed.

1. DISCOVERY

The team found fossils on a prior trip

to the Irhazer Plain, preserving them

from erosion with a plaster cap.

In 2022, they returned to excavate

the mysterious animals.

2. MAPPING WITH PHOTOS

Hundreds of photos from drones

and handheld cameras recorded the

excavation’s progress. Anchor points

common to the images allowed

photogrammetry software

to connect them.

3. EXCAVATION

The team carefully brushed and

chipped away rock and dirt surroun-

ding fossils, using hand andpower

tools. Fossil measurements and

positioningdata could be gleaned

from the digital models.

4. FOSSIL PREPARATION

Fossils freed from most of their

surroundingrock were wrapped in

casts, called jackets.Wooden braces

helped protect brittle orfractured

fossils during transport.

Graphic: Fernando G. Baptista,

Patricia Healy, and Lucas Petrin,

NGM Staff. 3D renders by Daniel Vidal.

Sources: Paul Sereno, University of

Chicago; Daniel Vidal, UNED & University

of Chicago