This earthcache is on private property and placed with permission.
Please be respectful, limit your visits to daytime only and do not visit during mass times which are available on the church's website - St.Boniface Mass Times
This earthcache involves visiting some rocks used in construction, taking some photos and sending your observations to the CO. No science degrees or complicated answers are necessary and I hope you learn something new and see something neat. I've included the tasks with the description, as well as a list at the end and attached to each waypoint to make it easier in your preferred approach.
Maryhill is a quiet, rural community that's topography had been modified by glacial and post-glacial activity. It was originally called New Germany, renamed Maryhill in 1941 since the church was on the hill (drumlin) and the people wished to place the village under the patronage of the Blessed Virgin Mary. Two glaciers, one from the Grenville Province in the northeast, and the other from the Superior Province in the northwest met in this region.
Construction
The longer side walls of the church are made of what is known as fieldstone. Fieldstone is simply a random assortment of rocks from farmer’s fields and streams around the area. These are referred to as glacial erratic’s, which were carried here by the glacier and are not native to this area. Most of these come from Eastern Ontario, from the Grenville province, where the rocks are about 1 billion years old.
Using local fieldstone in the 1877 construction of the church was an alternative to quarrying stones or manufacturing bricks. It provided a ready source of construction material.
Two main styles of construction by stone masons were common: Scottish immigrants preferred to refashion the stone into regular, rectangular blocks; other immigrants, largely of German origin, split the stones, but otherwise did not refashion their shape. In this second case, a large amount of mortar was required.
The side wall buttresses, window frames, and front of the church are constructed from local bedrock. The Guelph formation (calcium magnesium carbonate) dolostone was quarried locally and contains preserved fossils dating back to the Silurian Period.
The church sign, cairn of the historic bell across the street, rock wall along the cemetery north of the church and the pillars of the newer cemetery across the road were built much later and contain fieldstones and erratics from the Superior Province, including the Canadian Shield, and Lake Huron via a different glacial delivery route
Tasks
From the parking lot, go to the rear of the church building and walk around to the north side of the building.
Stage 1 - Gneiss Garnets - N 43 32.199 W 080 23.549 ( descriptions and instructions have also been added to waypoints)
A characteristic rock of the Grenville Province is a gneiss. There are a great variety of these rocks, depending on the variability of its mineral content. Layers in the rock have been warped and pressed and squeezed by crustal forces. When the rock was softened by heat and plastic it could be moved, squeezed, and bent in various shapes. The bands in the rock are different mineral concentrations: light bands could include feldspar or quartz; dark bands may include hornblende or various kinds of mica. In general, a mix of various minerals form a rock called gneiss.
One of them here has a concentration of garnet, which are reddish colour; they can be a semi-precious stone that is used in jewellery. You may see examples of various combinations of mineral colours in gneiss here. The rock you are looking for here, has two colours, a yellowish beige and a darker grey and placed under the third window from the front of the building.
Take a picture of a personal item - GPS, your thumbs up, your geocaching name, you etc , and garnets in gneiss rock and include it with your log. HINT - rock is two coloured, under 3rd window from front of building. The rock might resemble a Pac Man with it's mouth wide open.
Stage 2 - Crinoids, Crinoids, Crinoids - N 43° 32.198′ W 80° 23.551′
Three of the most interesting specimens of the rock wall in this section are full of fossils. These fossils, which almost the entire rocks are made of, are called crinoids. Crinoids sometimes are called sea-lilies but in fact are animals. Some still live in the ocean, in warm tropical waters. Their root system on the sea floor extends upward. This stem is mainly what is seen in fossils as stick-like. At the top of what can be a long stem is where the creature that resembles a starfish lives. It collects food from the water with its long arms.
1. Take a picture of a personal item - GPS, your thumbs up, your geocaching name, you, etc. with of one of the three stones with many fossils and include it with your log. HINT - 1 to 2 m high, under and to the right of 2nd window from front of church.
2. Do you think these came from the Grenville province or were local rocks? Include your answer in an email or GC message to the CO.
Stage 3 - Building Construction - N 43 32.195 W 080 23.559
From here you can see a side wall and the front wall of the church.
1. Do you think the church, in particular the side walls were built using the German or Scottish style of fieldstone construction? What are two reasons for your answer? email or message these answers to the CO.
2. Why is the front of the church, buttresses, window frames constructed of a different material? What are two reasons? Are they constructed in the German or Scottish style? email or message these answers to the CO.
Stage 4 - Stromatolites - N 43 32.182 W 080 23.553
The front of the church is constructed of rectangular blocks of stone. Some of these rocks appear to be calcium magnesium carbonate (dolostone), which probably comes from the local bedrock. The bedrock here is similar in composition, all the way to the city of Guelph. It is called the Guelph Formation, and it’s of Silurian age. The rock often has fossils in it due to its sedimentary nature. There are three sets of doors at the front of the church. Near the right set of doors of the church we can find some fossils that may look like a cross section of a cabbage with little layers going round to the middle. These fossils are stromatolites, which are a type of an algal structure. Even now, Stromatolites are found in the sea, and form these characteristic cabbage-like structures.
1. Take a photo of the larger Stromatolites with an identifiable object, include with your log.
2. Do you see other fossils in the dolomite stones on the front wall of the church? If you do, most are from clams. No need to message CO.
HINT - to the right of the right set of double doors.
Stage 5 - Old Walled Cemetery Wall - N 43° 32.202′ W 80° 23.579′
Built in 1862 at a cost of $1002.92 this wall has many more excellent samples of fieldstone. It includes boulders of Paleozoic age as well as of Precambrian age. We can see some fine examples of quartzite, which began as a sand deposit. Over time, this sandy deposit was turned into sandstone. Then, through heat and pressure, the sandstone was metamorphosed to form quartzite, one of the toughest kinds of rock. Interestingly, quartzite has been used by First Nation people to create projectile points from quartzite deposits up on Manitoulin Island. Chert is used instead in southern Ontario too, but is commonly referred to by archaeologists as flint. The rock that looks like Swiss cheese is marble with pitting. (pictured below)
The pictured below stone is an example of boudinage. It is named for the French word for sausage - Boudain. The rock layer was stretched out, and then squeezed to appear as links of sausage. There are three "links" in this photo.
In your log, include a photo of your favourite rock in the wall, and if you would like, what was interesting about it.
Logging Requirements - please send your answers to the CO via email or message through the Geocaching website. You are welcome to log your find and I will contact you if there is an issue with your answers. Answers can be found in the cache description, online and your observations on site.
Stage 1 – Gneiss Garnets
1. Take a picture of a personal item - GPS, your thumbs up, your geocaching name, you etc , and garnets in gneiss rock and include it with your log. HINT - Rock is two coloured, under 3rd window from front of church.
Stage 2 – Crinoids, Crinoids, Crinoids
1. Take a picture of a personal item - GPS, your thumbs up, your geocaching name, you, etc. with of one of the three stones with many fossils and include it with your log. HINT - 1 to 2 m high, under and to the right of 2nd window from front of church.
2. Do you think these came from the Grenville province or were local rocks? Include your answer in an email or GC message to the CO.
Stage 3 – Building Construction
1. Do you think the church, in particular the side walls were built using the German or Scottish style of fieldstone construction? What are two reasons for your answer?
2. Why is the front of the church, buttresses, window frames constructed of a different material? What are two reasons? Are they constructed in the German or Scottish style?
Stage 4 – Stromatolites
1. Take a photo of the larger Stromatolites with an identifiable object, include with your log.
2. Do you see other fossils in the dolomite stones on the front wall of the church?
HINT - to the right of the right set of double doors.
Stage 5 – Old Walled Cemetery Wall
1. In your log, include a photo of your favourite rock in the wall, and if you would like, what was interesting about it.
Sources:
Peter Russell, retired curator of the Earth Sciences Museum at the University of Waterloo
https://uwaterloo.ca/wat-on-earth/news/maryhill-near-kitchener-ontario-glacial-landforms
https://stboniface-maryhill.ca/history/
https://www.ontariobeneathourfeet.com/ice-age-glacial-erratic
https://www.raisethehammer.org/article/1491/use_of_fieldstone_in_southern_ontario_buildings
https://maryhillroots.com/wp-content/uploads/2020/11/glacial-features-of-maryhill-by-peter-russell.pdf
https://planetrocks.utsc.utoronto.ca/
https://geology.com/rocks/
Fun facts – you might notice houses in town that are constructed of yellow brick. These were formed using local area clay. The lime (calcium carbonate) is responsible for the yellow colour. Adding colouring material could make red bricks at an extra cost. Some people would do red brick at the front of their houses for prosperity and yellow on the sides.
Most of the rocks in the south side of the church contain mica and therefore sparkle in the bright sunshine.
In the timeline of a rock, humans are but a flash.
To the left of the significant stromatolites there are numerous small fossils of clams. They appear as irregularly shaped holes in the dolostone
The entrance pillars to the cemetery across the road, the church sign monument, and the historical bell monument across the road have great samples of rocks that you can examine up close as well.