Geologic Tour to the Goblin Colony

Spend a day exploring the diverse geology of the Southeast Jemez Mountains and a “secret” basin called the Goblin Colony with PEEC and local geologists Fraser and Cathy Goff. We will first look at the southern lip of Valles Caldera (1.23 Ma), enjoying a beautiful view of Redondo Peak. Then we’ll head south to an exposure of pre-caldera andesite lava (about 8 Ma) and next examine a faulted deposit of Santa Fe Group sediments (about 15 Ma). We’ll then continue south and end with a 2.2-mile round trip hike into the Goblin Colony, a very unusual deposit of altered Tshirege Member, Bandelier Tuff. We’ll pass a basalt lava flow and two intrusions of dacite along the way. We guarantee that your cameras will be buzzing while varied explanations for the deposit are discussed.

The field trip is limited to 25 people, and carpooling may be necessary. Participants will meet at the Los Alamos Nature Center at 8:30 AM on Saturday, June 27th, and drive west along NM Highway 4 to Forest Service Road 10. All stops will be along the improved gravel and dirt road (no high-clearance or 4WD required). We’ll eat lunch (not provided by PEEC) in the shade of the ”goblins” and return to our cars around 3:15 PM. The elevation rise at the “goblins” is 140 feet in moderately steep terrain covered by pumice and pines. Bring light boots, hiking sticks (optional), appropriate layered clothing, hat, sunscreen, sunglasses, small pack, camera, 1-2 quarts of water, lunch, and additional beverages and snacks (optional). We should be back at the nature center parking lot at around 4:30 PM. Registration is required to participate in this tour.

Admission: $60 for PEEC Members and $75 for Non-Members

About Trip Leaders:

Fraser Goff is the author of Valles Caldera: A Geologic History and is the lead author of the recently published Geologic Map of the Valles Caldera (2011). He worked at Los Alamos National Laboratory for 26 years. He has worked extensively in the Valles Caldera and other volcanic sites around New Mexico, and on about 40 geothermal systems and 15 active volcanoes worldwide during his career.

Cathy Goff is also an accomplished geologist/geochemist and has worked on geothermal and volcanic projects throughout the western USA (including Alaska and Hawaii), Latin America, Italy, and Japan. Most recently, Fraser and Cathy worked for the New Mexico State Map Program and helped produce the color Geologic Map of the Mount Taylor volcano area, New Mexico (2019).