Monday, 1 June, 2026/Edition 113

June 5 is World Environment Day, a celebration that dates back to the United Nations Stockholm Conference on the Human Environment in 1972.

This week, we will look at the biosphere in geoscience, examine geothermal systems in the Rocky Mountains, and end with the origin of the term Wolfcamp Formation.

Rasoul Sorkhabi

Editor, Core Elements

Two Recent Papers on the Biosphere in the Anthropocene

Me Dia/Shutterstock.com

A recent edition of the Philosophical Transactions of the Royal Society of London includes interesting studies on the biosphere in the Anthropocene. Let’s take a look at key points from two articles in this issue.

The biosphere over time: Mark William and colleagues in an introductory article review the evolution of the biosphere concept.

• James Hutton, a founding father of geology, a farmer, and a non-practicing physician, viewed Earth as a super-organism.
• The Austrian geologist Eduard Suess in 1875 coined the term “biosphere.”
• Russian geochemist Vladimir Vernadasky popularized “biosphere” in a book of the same title in 1926. It was translated to English in 1986.
• British geochemist James Lovelock proposed the Gaia theory, arguing that Earth and life are an integrated, self-regulating system.

Age of the biosphere: Earth’s biosphere is about four billion years old.

New roles for paleontology: In another paper, Williams and colleagues discuss the roles of paleontology and the fossil record in discourses on the Anthropocene.

Stories and science: The authors suggest two frontiers of action for paleontologists—stories and science.

• Storytelling is an impactful approach to sharing paleontology findings with the public.
• For the science portion, the authors suggest paleontologists look at:
  • Extinctions: There have been five main mass extinctions during the past 540 million years of Earth’s history. Understanding their triggers, processes, and consequences is of paramount importance for humanity’s own future.
  • Rates of environmental change: Paleontologists could examine which geological events alter the global environment and how we can compare the rates of these environmental changes for past and present times.

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Structural Controls on Geothermal Systems in the Rockies

South Canyon Hot Springs in the Rockies/Her Endless Journey/Shutterstock.com

The April issue of RMAG Outcrop has an interesting article on a quantitative analysis of fault-controlled permeability in geothermal systems in the Rocky Mountains.

Data distribution: Moones Alamooti, from the University of North Dakota, conducted this study on 47 documented geothermal systems in 11 states:

• Nevada (18), Utah (5), New Mexico (3), Idaho (4), Montana (3), Wyoming (3), Colorado (3), Arizona (2), North Dakota (3), South Dakota (2), and Minnesota (1)
• Temperatures in these geothermal fields range from 50 to 240 degrees Celsius.

Data input in the study included:

• Location, temperature, heat flow, and production data of geothermal systems
• Strike, dip, displacement, and stresses of faults

What researchers found:

Faults: 91 percent of systems are associated with mapped faults consisting of:

• Normal faults (74 percent), strike-slip faults (19), and reverse faults (7)
• Normal faults cluster within plus/minus 20 degrees perpendicular to the minimum horizontal stress with preferred dip angles of 60 to 70 degrees.

Fault intersection: Forty-five percent of the systems occur at fault intersections.

• High temperatures occur at intersection angles of 40 to 80 degrees.

Slip and dilation tendency: Slip and dilation tendencies were estimated from fault stresses.

• Slip tendency measures how close a fault is to frictional failure.
• Dilation tendency measures fracture opening tendency.
• Geothermal systems have a high slip tendency (0.68) when compared to background faults (0.43).
• High temperatures (more than 120 degrees C) exhibit the highest slip tendency values (0.73).
• Dilation tendency values average 0.42 for high-temperature systems.

Permeability and displacement: Data from 23 systems yielded a strong power-law correlation between permeability and fault displacement.

• Normal faults show higher permeability than other faults.
• Systems with active seismicity plot above the regression line.

Why it matters:

• Fracture permeability is a key contributor to geothermal systems.
• This paper is a first-step comprehensive assessment of fracture and tectonic controls on the efficiency of geothermal fields in the Rockies.

Introducing: The Lighthearted Layer

The Wolfcamp Formation was named for a camp frequented by wolves. Paarsad/Shutterstock.com

For such an important source rock in the Permian Basin, the Wolfcamp Formation got its name in a strange way… and it’s a name that’s not even accepted in American stratigraphy!

Did you know that…

• The Wolfcamp Formation was named for an abandoned settlement in the southern part of the Glass Mountains, which was said to be frequently visited by wolves.
  • The name was coined in 1917 for the shale formation of Lower Permian age that outcropped on the Glass Mountains in southwest Texas.
  • The accepted names for the outcrop formation in American stratigraphy are the Neal Ranch (lower) and Lenox Hill (upper) formations.
  • Wayne Camp in AAPG Bulletin suggested formalizing the stratigraphic term Wolfcamp Formation in the Permian Basin.

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