The Kitsilano Foreshore is an excellent location to view the geology of the Vancouver area. The low cliffs along the shore show layers of rocks that were deposited in ancient river channels, and low tides reveal flat beds of mud and clay that preserve fossil plant remains and thin seams of coal.
The rocks and sediments exposed are part of the Kitsilano Formation, which is the upper of two continental sedimentary formations which dominate the local geology. These layers are tilted at about 10 degrees to the northwest into the Whatcom Basin, a topographic and structural low that is about 75 kilometres across (stretching from the Coast Mountains north or Vancouver to Bellingham in the south). The sediments that create the rocks here were deposited in the late Eocene or possibly early Oligocene, so about 40 million years ago.
The layers are around 760m thick, so what we see exposed on the shore is only around 1% of the total formation. The very lowest part of the Kitsilano Formation was observed by the Second Narrows Bridge and consisted of imbricated conglomerates which suggested a westerly flowing river. The primary rock type are coarse-grained sandstone which are often cross-bedded and occasionally contain small lenses of lignitc coals. Shales are also common and preserve fossil leaves.
Fossilized remains of leaves and pollen are common in the Kitsilano Formation. Formal papers on this site have not been written since the 1960’s, but in that work many recognizable species were named. The gallery below shows some of the key species found in the foreshore deposits.
Fossil evidence can be used to help determine what the ancient environment was like. Plants are especially good indicators as, unlike animals, they cannot migrate with changing conditions and so tend to die off and get replaced by more suitable species in that area.
Modern species of the plant assemblage tend to live in warm temperate to subtropical areas. Many of the species are found today in low ground which is moist and poorly drained coastal areas. Others exist in ponds or lakes indicating standing water.
Other plants, such as the pines and oaks, would prefer higher and drier ground, and so were likely not living in this area, but their leaves were being transported by rivers along with the sediments and getting buried and preserved. They could have been living on the edges of the Whatcom Basin to the north, east or south of the modern foreshore.
The rocks and sediments we find on the foreshore suggest a terrestrial environment passing into shallow water, such as a river mouth where there were multiple stream channels passing over a sandy alluvial plain, with quiet lagoonal, pond or marshy zones where mud could accumulate, passing into more sandy deltaic zones, perhaps looking something like the image below:
Taxodium sp. trees with ferns in a drier forest setting with low lying shrubs, broad leaf trees and other vegetation (photo credit University of Delaware)
One of the mysteries of the Kitsilano Foreshore deposits is that, so far, no animal fossils have been found. This is unusual for several reasons:
1) The environment was productive and would have supported a wide variety of animal life, from fish to insects and even small mammals.
2) Leaves only preserve under very special circumstances, such as rapid burial, fine sediments and anoxic conditions. Teeth, bones and insects are much more resilient than plant matter and so would usually preserve well
3) Other similar deposits in British Columbia such as the Cache Creek (McAbee) Fossil Beds produce fossil plants and animals in layers of mud and silt.
We do think we have found evidence of animals in the form of “leaf mines” where a mite or some other plant eating animal grazed on broad deciduous leaves.
So why do we think we have not found any animal fossils? It is likely down to the ‘sampling size’ of specimens collected from the foreshore. The leaf-bearing layers are restricted in size and collection is from loose blocks. These layers are also thin and inter-bedded with the sandstone, which is much less likely to preserve animal remains due to the coarse grain size, high energy deposition and acidic nature that can dissolve organic material upon burial.
Many of the animals we would expect such as freshwater fish and flying insects such as mayflies could be so mixed with the leaves that they are hard to distinguish.
Finding animal fossils on the Kitsilano Foreshore would be an important discovery and we hope that one day soon they will be found!
Large ant fossil from the McAbee Fossil Beds (photo credit Simon Fraser University)
The foreshore at Kitsilano represents a great location to explore the geology of the Vancouver area, with many types of geology and even fossils exposed in the low cliffs and outcrops.
The map shows key locations and provides links to additional information.
Below BC has built up a range of data and virtual experiences for this site that can be used for teaching geological basics. Please refer to the sections below the map for full details.
Use the links below to access more information for class exercises, data and other useful information.
Field Data: Excel spreadsheet of all field data points (Last updated 15th May 2020)
Drill Data: Basic downhole information from BC Hydro drilling at Nelson Park, West End Vancouver
Basemaps: Series of blank maps of the foreshore for students to plot data
Rock Chips: Images of representative rock chips listed in the Field Data Sheet
Fossil Material: Images of fossils collected from the foreshore
Paleochannel Slider: Further information about the channel sections
The following material refers to geotechnical data donated to Below BC by BC Hydro. The drilling took place in Nelson Park, West End area of Vancouver.
Palynology Paper: Palynology of the Eocene Kitsilano Formation, sw British Columbia (Hopkins, 1969)
Collection of Fossils: The button below links to the Provincial laws and regulations governing the collection and use of fossil material. We encourage all users to familiarize themselves with these guidelines!