Hello people!!

Welcome to Peri Lithon! In this section you will find the author’s collection of photos that are directly and indirectly related to the magnificent terrestrial features that characterize our Earth as we know it. Most of these photos are taken directly from the author’s university-based field trips, but it is hoped that someday it will also host files from the numerous personal geology excursions that the author hopes and plans to undertake.

Just like Project: From Sea To Sea, Peri Lithon will be a constantly evolving page, changing over time to meet the author’s personal needs, interests and depth of resources at hand. As of now this location is still under construction, but keep checking back soon – I have lots of amazing course field trips planned on my academic schedule!!

On this page I will also endeavour to jot down some of the knowledge of geology that I have gained over the past few years of my life; to me, the earth sciences are a truly amazing subject as a whole, and I hope to share some of this infectious enthusiasm with my friends and readers. Trust me, all this will definitely allow you to appreciate our home planet even more, and marvel at the beauty and complexity of His creation.

I hope you’ll enjoy looking and reading about these geological features as much as I enjoyed studying them!

Cheers!

- Irving.

PERI LITHON 1:

Exhibit A -

Where is this?

This picture was taken at Victoria Island, which is a small isle on the Ottawa River; this photo was taken in the Fall of 2008.

What is that?

Those undulating and uneven lines that extend the length of the outcrop (N.B.: outcrop = rocks that are visible i.e they crop out above the ground) are actually a cross section of symmetrical ripples.  To help you grasp this concept, imagine that you have a physical wave undulating up and down on a flat bed; hold this wave, and then cut a line perpendicular to its direction of propagation – this is what you would see on the inside.

I should mention that the blue pen on the right is held by Rita Dali, one of my Geology coursemates. It – as you can probably tell – is for scale.

Why do I think they are cool?

Ripples are symmetrical subaerial structures that can be created by two forces – that of wind or water. The very fact that we are seeing them here – fifty meters from the nearest body of water, and at least ten feet above it – should make you go “Hey…that’s weird.”

Yup you got it right: we’re seeing wave marks, and they’re located way up high on dry land on rocks which are at least 500 million years old! What does that tell us? A hell lot actually – for one, it tells us that this area was actually flooded by considerable amounts of water thousands of years ago. Not only that, the size of the grains (small and fine) also tell us that the waters must have been reasonably calm, otherwise these light sediments would not have been able to come out of suspension and form the sedimentary outcrop that we are seeing here. Cool eh?

Exhibit B -

Where is this?

This picture was taken in the Fall of 2008 at Terry Fox Drive in Kanata, approximately half an hour’s drive from downtown Ottawa.

What is that?

So I showed you the cross-section of ripples earlier; this is how they look like from the top.

Why do I think they are cool?

For those of you based in Ottawa – and also those who have been to Terry Fox Drive or the nearby Centrum Mall – you would know that the area is NOWHERE near a body of water at all. So I showed you the ripples on Victoria Island; I guess it actuality it wasn’t that much of a stretch for the imagination to visualize massive amounts of water swamping around the area right (well, it WAS an island!!)? Take it from me – this set of ripples you see here is literally MILES away from any body of water.

Yet we see them here – again, proof that Ottawa once contained a massive marine environment once upon a time. We even know the name of the body of water that did this – modern geologists call it the Champlain Sea, and it is approximated to be around 12,000 years ago. Now how many generations away is that?

Exhibit C -

Where is this?

This is another shot from the Centrum Mall area; just opposite the mall, across Kanata Drive, sit several tonnes worth of sandstone rocks infused with carbonate cements.

What is that?

The Nepean Sandstone is perhaps one of the more prominent outcrops to be deposited in the National Capital Area; approximated to be about 500 million years old, the Nepean can be found stretching all around Ottawa, and even some regions of Hull and Gatineau – in Quebec. This particular sediment contains carbonate cements, which means it fizzes when acid is sprinkled on its calcite-possessing surfaces.

Why do I think it is cool?

I am going to recite one well known geological principle and then sign off for the night – hopefully you guys will be able to grasp the significance of the theory and how it applies to this rock formation!! Ready? Here goes -

“The Principle of Original Horizontality states that layers of sediment are always deposited horizontally, and any change in orientation implies that there has been tectonic movement in the area.”

Now look at how those rocks are oriented. Amazing eh?

Goodnight folks!! =)