Fossils on Burnaby Mountain

April 20, 2023

Biological Sciences professor Rolf Mathewes and colleagues recently published a paper in the International Journal of Plant Sciences focussed on the fossils under our feet at the SFU campus. The results of their plant fossil analysis were recently published in the International Journal of Plant Sciences. Read more in SFU News, and listen to Rolf's interview with Nil Köksal on the April 17 episode of CBC Radio's "As It Happens". The interview starts at around 57:38 mins.

The study has interesting connections to the history of the campus, since the collection of plant fossils described in this paper were originally collected in the late 1960s during early construction of SFU.  The fossils were collected by Biological Sciences professor Robert C. Brooke (deceased), and by Rolf Mathewes as a charter undergraduate student working in Dr. Brooke's lab.  The fossils have been stored at SFU since collection and never analyzed until now.

Since becoming a paleobotanist, and starting at SFU as an Assistant Professor in 1975, Rolf inherited this small collection of fossils, and only started to seriously work on them a few years ago. He finally published the Burnaby Mountain collection and its environmental details, with colleagues David R. Greenwood (Brandon University) and Tammo Reichgelt (University of Connecticut).

Hydrangea flower. Photo: Rolf Mathewes
Leaf of oak family. Photo: Rolf Mathewes
Sabalites SFU palm leaf fragment. Photo: Rolf Mathewes

There are some beautiful and interesting fossils, including flowers and fruits as well as leaves, and a fragment of a palm leaf!  All the fossils were formed when there was no mountain here, closer to sea level on an ancient floodplain.  They are now at the top of Burnaby Mountain and tilted south due to uplift from the early Coast Mountains to the north.  Palm fossils were common in older sediments near the Stanley Park sea cliffs, during a particularly warm period about 10 million years before the Burnaby Mountain fossils were formed.

The climate during the estimated age of the fossils around 40 million years ago (estimated only based on the fossils) was warmer than today, similar to present day warm temperate to marginally subtropical climate around Wilmington North Carolina on the eastern USA coast, where palms are still native today.

During this study, Rolf noted an extension of the original fossil bed in the excavation for the new Student Union building (Photo Fig.3), and compared it to the 1960s excavation, located behind the current Mackenzie Cafeteria. That is why there are no windows in the wall at the back of the cafeteria.

Fig.3 Rolf Mathewes as an undergraduate student in 1967 holding a 0.5-m ruler against the shale bed; Rolf again in 2016 beside the SFU Student Union excavation.