The Geologist is a character in The Precursor Legacy. She is a young woman studying the geology of Rock Village and the neighboring Precursor Basin. She is distinguished for being the discoverer of the lightning mole. Her subsequent research involved "studying the burrowing habbits" of the moles for several years prior to the events in The Precursor Legacy. When a band of robbers invaded the Basin and scared the lightning moles out of their nesting holes, the Geologist tasked Jak and Daxter with the mission "Herd the moles into their hole", during which Jak had to chase the moles back underground using the A-Grav Zoomer, as they were too blind to find their own way. She offered Jak a power cell in exchange, and additionally asked them to bring her ninety Precursor orbs for research supplies.
The Geologist speaks with a distinct English accent much like the Explorer, and has an evident love of wildlife. She has red hair and wears clothing typical to the outdoors, with a large torchlight helmet, a teal-blue aviation helmet, gray tunic with a teal-blue vest, and brown pants.