Joeri Witteveen on Golden Spikes

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The geological timescale is organized as a hierarchy of time spans. When we talk about the ages of rocks, or when certain events in the geological past took place, we need to use a system that unambiguously defines a time in geological history. This is by no means a trivial problem. In the podcast, Joeri Witteveen describes the various approaches that have been adopted in the past, and explains the system based on golden spikes that we use today.

Witteveen is Associate Professor of History and Philosophy of Science at the University of Copenhagen.

A man with curly dark hair wearing a light blue dress shirt, smiling, in an indoor setting with large windows in the background.
An international chronostratigraphic chart displaying the geological time scale from the Precambrian to the Quaternary period, divided into various epochs, ages, and stages with color-coded sections and numerical age estimates.

The December 2024 version of the international chronostratigraphic chart. The right-hand part of each column lists the stages/ages. Each stages is a specific, formally defined interval of rock strata that represents a corresponding interval of time called an age. Golden spikes are marked at the base of the stages they define.

Golden Spike at the Base of the Selandian Stage, Zumaia, Spain

Photos courtesy of Stanley Finney

Group of people exploring a cliffside and beach, examining geological formations and taking part in geological or archaeological activities.

(A), (B) Participants of the 2006 conference at which the golden spike for the base of Selandian Stage in the Paleocene was dedicated in Spain. (C) Unveiling of an interpretive panel. (D) Golden spike created for the dedication ceremony. (E) Officials placing the golden spike. (F) Representatives of the local government, local scientists, and members of the International Commission on Stratigraphy.

Title page of a scientific report titled 'Zumaia Section,' discussing the global stratotype for the base of the Selandian Stage, including coordinates, a brief description, and logos of the International Commission on Stratigraphy, International Union of Geological Sciences, and Gipuzkoa Foro Aldundia, with a date of 06/05/2010.

Marker plaque for the golden spike at the base of the Selandian Stage.

Students taking part in a boat trip with a spectacular view of the Zumaia section Geopark.

close-up view of a rocky surface with an orange marker that has the letters 'GSSP' engraved on it, indicating a specific geological point.

Golden spike at the base of the Selandian Stage, Zumaia, Spain.

Group of people on a boat ride near rocky shoreline.
An image of a riverbank with geological markings and annotations, showing the highest water level at 3 meters above a point, GSSP markers, Laibin Limestone, and the Heshan Formation with labeled rock layers and fossils.

Relocation of the golden spike at the base of the Wuchiapingian Stage necessitated by flooding of the Hongshui River caused by construction of a dam 80 km downstream on the Pearl River. The original golden spike is now about 5 m below the surface. The new location was placed at a slightly different stratigraphic level with the potential for greater correlation of the boundary around the globe. As Witteveen points out in the podcast, a strictly local event resulted in the global redefinition of the base of the Wuchiapingian Stage.

Shu-zhong Shen, et al. (2023), Episodes 47, 147

A monument with a tall, white, obelisk-like structure topped with a swan figure, situated against a rocky, green hillside, featuring inscriptions and an open book sculpture at the base.

Locations of golden spikes as of early 2020. The circles are color-coded according to the colors of their corresponding stages on the chronostratigraphic chart.

Gradstein, F. M., et al. (2020), The Chronostratigraphic Scale, Elsevier

Monument at the golden spike at Meishan, China, marking the boundary between the Permian and the Triassic.

Interior of a modern exhibition or science center with colorful lighting, a circular ceiling fixture, and interactive display stations.

Geological museum at Meishan includes a hall on the golden spike and an enlarged model of a conodont species, which makes its first appearance above this golden spike and is key to the definition of the base of the Triassic.

World map showing locations used to calibrate M-sequence and C-sequence, with different colored dots across continents.

Further Reading

Witteveen, J. (2024), Golden spikes, scientific types, and the ma(r)king of deep time, Studies in History and Philosophy of Science 106, 70

Gradstein, F. M. and Ogg, J. G. (2020), The Geologic Time Scale, Elsevier BV

Finney, S. C. and Hilario, A. (2018), Geoheritage, Chapter 10 GSSPs As International Geostandards and as Global Geoheritage, Elsevier BV