Geology of the Canadian Museum for Human Rights: Part 3

By Dr. Graham Young, past Curator of Palaeontology & Geology

Columnar jointing is a term used to describe the polygonal columns seen in many volcanic rocks. These developed as a result of stresses, when lava cools from a molten form. Famous columnar basalts can be seen in places like the Giant’s Causeway in Northern Ireland, and at many sites around the Bay of Fundy in eastern Canada (columnar-jointed bedrock in the Lake Nipigon area of Ontario has a similar appearance, though much of it may have actually formed from magma that was intruded between other rocks, rather than erupted onto the Earth’s surface).

By Dr. Graham Young, past Curator of Palaeontology & Geology

Having received a tour of the interior construction site in April, followed up more recently by careful examination of the building’s exterior, I have to respond to this question with a full-voiced “yes.” The CMHR does not contain as great a variety of building stones as some older buildings in downtown Winnipeg, but some of the materials are of types not readily seen in other structures, and the immense scale of the structure permits a geological experience that may be unparalleled elsewhere in this town.

The following descriptions are based largely on my brief observations of a building still very much under construction, along with what I could glean from the web and some information received from helpful staff at CMHR. Since a thorough examination is not possible at this stage, and since surfaces were still being installed when I saw them, it is entirely probable that I have missed or misinterpreted some of the geological materials. I am also, for the moment, ignoring the site geology and materials other than stone. At some point in the future I hope that we can write a detailed consideration of CMHR’s geology, comparable to our work on the Manitoba Legislative Building (a pdf can be found here).

To a Winnipegger walking outside the CMHR, the immense surfaces of Manitoba Tyndall Stone are both familiar and obvious. Since this stone is locally ubiquitous, I will instead begin with the more unusual materials in the museum’s interior. As you enter the building, some of the introductory areas seem dark and low, walled largely with ochre-coloured concrete along with feature walls of other materials. Passing upward into more open spaces, you have your first glance of the extensive ramp system that allows visitors to walk through the many museum areas.

The walking surfaces of the ramps are concrete, but the sides are Spanish alabaster, quarried in Zaragoza, Aragon, Spain. Alabaster is a translucent, lustrous stone, long used by humans because it is beautiful and easy to work with. The CMHR alabaster is cut quite thin, about 2 cm (or 3/4″), and with the natural light it glows magically when backlit.

Geologically, two major types of material are considered as “alabasters”: gypsum (hydrous sulfate of calcium) and calcite (calcium carbonate). Neither kind of alabaster is resistant to rain and moisture, so both are only suitable for indoor use. The CMHR alabaster is of the gypsum sort; it is quite a soft material, but the crystals are tiny and tightly bound together, permitting both the polish and the translucent quality. Pure alabaster is white, and the beautiful colours and patterns actually come from impurities such as clays.

The Aragonese alabaster was quarried from near-horizontal beds in the Ebro Basin of northeastern Spain. It formed during the Oligocene and Miocene epochs (roughly 34 to 5 million years ago). During this interval, the Ebro Basin was endorheic (i.e., it had internal drainage and was not connected to the sea). As a result the water often became very saline (briny), and salts were precipitated out to form bedded chemical rock, most notably the gypsum that makes up this alabaster. The Aragonese alabaster is quarried by Alabaster New Concept.

Manitoba also has considerable gypsum deposits in our Jurassic sedimentary rocks. These can be seen at places such as Gypsumville and Amaranth, but as far as I know there is none of alabaster grade.

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Part 2 of this geological tour will follow soon, with an explanation of the dark stone that can be seen in the spectacular Garden of Contemplation and other places in the museum’s interior.

By Dr. Graham Young, past Curator of Palaeontology & Geology

Looking through my window at the still-snowy, still-wintry Winnipeg streetscape, I have to remind myself that spring is not far away. Soon the snow will leave and we will again be able to begin one of the most pleasurable of the Museum’s activities: fieldwork. Last year, between various other projects, I worked with Bob Elias (University of Manitoba) and Ed Dobrzanski on gathering information that we could use in a field guidebook for this spring’s Winnipeg GAC-MAC meeting (Geological Association of Canada – Mineralogical Association of Canada).

The first trip, in late May, was after several days of rain. We found the right roads, we located the property on which the site should be located, and we met and received help from the very kind owners of the property. But the roads were continuous mud in places, and we were told that the field track to the site would be impassable that day. We would need to come back later when the weather had been dry for a while.

The second day was one of those hot, dry, breezy July days. The air motion was sufficient to cool us and to keep mosquitoes and flies from being too much of a nuisance. We drove through fields almost to the site, without even getting dirt on the car! Tucking trousers into socks to keep the nasty wood ticks from climbing our legs (this may look goofy, but it works), we pushed through the dense brush. We rapidly discovered four nice scarp sections in the trees. The farthest of these looked promising because it showed the best exposure of the Stonewall Formation, which lies under the Fisher Branch. This site, however, turned out to be already occupied: a bear grunted and huffed from the underlying crevice when we got too close!

We quickly decided to measure the next section along instead. Data and rock samples were easily gathered, but we could not get decent photos of the rocks because the view was blocked by foliage whichever way we turned. We would need to return in the autumn, after the trees had lost their leaves.

By mid October the leaves were all gone and the weather was still lovely; ideal for our final “day out” near Fisher Branch. We stopped at Stony Mountain and Stonewall to check out conditions at those localities, then drove north to Fisher Branch by lunchtime. In the field beside the sites we were met by a large herd of cows (perhaps the Interlake should be advertised as “Land of Cows”?), some of which became very interested in our Jeep. The bear was apparently no longer in residence at the farthest scarp, so we were free to examine the rock, take photographs, and gather a set of isotope samples. Later in the afternoon, we tramped up over the hill above the scarp, just to make sure that there was no further unexamined outcrop.

It was a perfect autumn day; the last perfect field day of the year, as it turned out. Our drive to Grand Rapids under rather less pleasant conditions was to follow just a couple of days later.

By Dr. Graham Young, past Curator of Palaeontology & Geology

Winnipeg has a long and complicated history of museums featuring natural history collections. Our current museum was a centennial project, opened in 1970, but we are very fortunate that we possess vestiges of those earlier museums, such as minerals from the Carnegie Library collection and mounted animals from some of the early taxidermists. The most visible and best-documented of these “inheritances” are pieces that were exhibited in the old Manitoba Museum, which occupied part of the Winnipeg Civic Auditorium from 1932 until about 1970.

In a way, though, we have kept some of that old Museum, in the specimens and artifacts we inherited. It is intriguing that, even after all this time, many of those fossils are still the best examples we have for particular groups, and several of them are in the Earth History Gallery or have been selected for temporary exhibits. The most obvious of these is our mounted Cretaceous plesiosaur, Trinacromerum kirki.

This specimen, collected from the Manitoba Escarpment near Treherne in 1932, was a highlight of the old museum. After several re-mountings (including a more accurate replica skull), it remains a focus of our Earth History Gallery today. Skeletons of large extinct creatures never go out of style, but what other fossils can also be traced to the old museum?

The exhibits there featured some beautiful specimens of cephalopods (relatives of octopus and squid) of Ordovician age (about 450 million years old). Ordovician cephalopods are familiar to many Winnipeggers because cut sections through these fossils are often seen in Tyndall Stone walls. Although the cut fossils are common, complete cephalopods are very rarely found nowadays, because the stone is cut directly out of the quarry walls.

In the early years of quarrying, however, the work was done by hand. Three-dimensional fossils were extracted more commonly, and as a result many of our best large Tyndall Stone fossils come from the old collections. This is particularly striking in the Ancient Seas exhibit, where the finest endocerid cephalopod is one that was on exhibit in the old museum, and where some of the other fossils also came from old collections.

Other specimens from the old museum make appearances almost every time we do a temporary exhibit in the Discovery Room, featuring  geology or paleontology pieces. Right at the moment, the cephalopod case in our Marvellous Molluscs exhibit includes a pair of fossils from that source. Looking at the old photographs, I was fascinated to discover that two “old friends” that shared a case in the old museum are right beside one another in this current exhibit!

There is something very pleasing about seeing them together like this, 70 years or so after that previous photo. In this way at least, the old museum lives on.

By Dr. Graham Young, past Curator of Palaeontology & Geology

When I started this blog a couple of years ago, one of my main intentions was to share the various items and phenomena that are within close reach of my desk, here on the 4th floor of the Museum tower. With that in mind, and since at lunchtime on New Year’s Eve we have reached a point in the year where serious and scholarly content should not be expected, I have decided to provide you with an annotated view of my office door.

In general, this curator’s door is far from curated, in the sense of having organized content. Rather, it is an odd mixture of items that I have randomly decided to exhibit, pieces that other people decided should be placed on my door, and things that seem to have flown in and stuck there all by themselves. With that in mind, the following is an annotated pictorial guide to items that can be seen on my door right now.

10. The definition of forthwith came from the brain of my friend Dave Rudkin. With this in mind, I am always happy to state that I will produce a document “forthwith.”

11. This lovely pen-and-ink sketch of the Ordovician branching coral Pragnellia arborescens is by Museum artist and preparator Debbie Thompson. It depicts the holotype of this species, specimen I-206.

12. A photo of the head (cranidium) of a Silurian trilobite from the Gaspé Peninsula of Québec is there to remind me of two things. First, it is an image I took 30 years ago using what is now ancient technology (a large-format film camera), and its tone and beauty demonstrate that new methods are not always the best methods. Second, since it is from a research project that I never completed, it is a reminder not to keep taking on new projects that I will not be able to finish!

13. The obligatory dinosaur cartoon.

14.  This is a Velociraptor-free workplace, and there have been no incidents since this sign was put up almost a month ago.

15. I produced this version of the Canadian flag for my other blog a couple of years ago, after reading Michael Flanders’ pronouncement from the 1960s that our flag looked like a dinosaur footprint.

16. This was a nice poster of a pyrite crystal, but it is sadly becoming greenish and tattered, and I really should replace it!