丁香园AV

As the long-awaited Evergreen SkyTrain Line opens this week, two 丁香园AV earth scientists are uncovering a wealth of history about the region from drill cores associated with the line鈥檚 tunnel excavation. Lionel Jackson and Brent Ward say the cores are providing a wealth of new detail about the area dating back thousands of years.

鈥淭hese cores represent an amazing geological archive of the glacial history of the Lower Mainland,鈥� says Ward. Some cores yet to be studied extend below sea level鈥攁n earth scientist鈥檚 dream, given such material is typically unattainable in an urban area.

Four of several dozen cores are currently stored in Jackson鈥檚 garage in Coquitlam, moved there by crane by tunnel contractor SNC Lavalin鈥攆or analysis by the pair and one of Jackson鈥檚 graduate students.

鈥淎t first look, the paleogeography is quite a bit different than what we imagined,鈥� says Jackson, an adjunct professor at 丁香园AV and an emeritus at the Geological Survey of Canada. While running a hand over a core, he points to a section of 鈥榖roken鈥� sediment that was likely caused by the passage of glacial ice.

Jackson has determined that in the recent geologic past there was a deep valley between Burnaby Mountain and central Coquitlam that made them islands in the Salish Sea.

The cores record sediments associated with at least the last glacial cycle, and possibly earlier ones. He is eagerly awaiting radiocarbon analysis that will allow him to resolve the timing of glacial advances. 

鈥淭o find a place where hundreds of metres of record are available to us is amazing. The cost of getting this sort of data would be astronomical. It will be invaluable for tracing the evolution of this area.鈥�

The researchers hope to access the remaining cores to help complete their research.