Cadom

ian

T imania

60°S

Australia

India

LaurentiaBaltica

SiberiaEast

Antarctica

Amazonia

WestAfrica

SouthChina

Kalahari

RioPlata

NorthChina

Seychelles

Madagascar

Congo Ava

lonia

n

30°N

30°S

n

The Supercontinent Rodinia750 Million Years Ago...

g thn ei r Ou rd d op va icM i ad nlr Po eW riod

Geology of the Kingston Area1.1 Billion Years of Earth History

Pangaea

Gondwana

Laurentia

Baltica

SouthChina

NorthChina

Australia

EastAntarctica

IndiaCongo

Siberia

60°S

Kalahari

Subduction zones Seafloor spreading axis

Amazonia

Rio

Plata

West

Afr

ica

Neotethys

Palaeotethys

Equator

30°N

30°S

250 million years ago

GeoEngineering Centre Field Trip 2013

Miller Museum of Geology,Miller Hall, Queen’s University

Field Trip Background Info: Minerals and Rocks

Rocks are made up of different kinds of minerals. The types of minerals, and the way that the rock formed, can be used to determine the environment in which the rock formed.

SedimentaryMetamorphic

Igneous

Magma/Lava

Changes dueto Heat and Pressure

Chemical and/orMechanicalSediments

The Rock Cycle

weath

erin

g o

r chem

ical d

eposition and lithification

c red ryn sa tagn lli iztl ae tioM n

gnit

ae

h ro/

dna l ai r uB

Igneous Rocks: Rocks formed from cooling molten liquids either intruded into the Earth’s crust or extruded on the surface of the Earth.

Sedimentary Rocks: Rocks formed from cementing of mechanically weathered sediments, or from chemically precipitated sediments.

Metamorphic Rocks: Rocks formed under tremendous heat and/or pressure.

The Earth is the ultimate recycler, and the rocks are converted from one type to another by natural geological processes over long time periods. Although nothing much seems to happen to the rocks in our lifetimes, if we could watch them over millions of years we would see tremendous changes in the rocks.

Classification of Rocks

Rock-forming Minerals and their Properties

Although there are thousands of different kinds of minerals, many rocks are only made up of a few common rock-forming minerals. Quartz, feldspar, and mica are common silicate minerals that are found in the igneous, sedimentary, and metamorphic rocks that we will see on the field trip in the afternoon. Calcite is a common carbonate mineral that we will see in several rocks as well.

The 8 most abundant elements in the Earth’s crust by weight % are:

Oxygen (O) 46.6%Silicon (Si) 27.7%Aluminum (Al) 8.1%Iron (Fe) 5.0%Calcium (Ca) 3.6%Sodium (Na) 2.8%Potassium (K) 2.6%Magnesium (Mg) 2.1%

Most of the common rock-forming minerals of the crust are silicates (based on silicon and oxygen compounds).

The Mohs Hardness Scale of Minerals

1. Talc2. Gypsum3. Calcite4. Fluorite5. Apatite6. Orthoclase7. Quartz8. Topaz9. Corundum10. Diamond

(Hardness of fingernail: ~2.5)

(Hardness of glass plate ~5.5)

Mica: Microcline Feldspar:

Quartz: Calcite:

Hematite:

– Page 1–

Amphibole:

Field Trip Preparation: Geological History of Kingston

1.8 - 1.3 billion years ago

Eroding mountains near present-day Sudbury, Ontario, deposit sediments in a shallow sea near present-day Kingston. Limestone forms in the ocean offshore.

Laurentia(Proto-North America)

Cadom

ian

T imania

60°S

Australia

India

LaurentiaBaltica

SiberiaEast

Antarctica

Amazonia

WestAfrica

SouthChina

Kalahari

RioPlata

NorthChina

Seychelles

Madagascar

Congo Ava

lonia

n

30°N

30°S

n

Shallow Sea(Covering present-day Kingston area)

Sandstone, conglomeratemudstone, Limestone

Erosion

1.3 billion - 950 million years ago

Collisions with other ancient continents produced the Grenville Mountains, folding and metamorphosing the pre-existing sediments. Igneous rocks intrude forming plutons, dykes and sills.

Laurentia(Proto-North America)

Grenville Orogeny

IgneousPlutonsIgneous

Dykes

Metamorphic gneiss, schist,quartzite, and marble

Ocean

Approximate Major Plate Boundaries

500 million years ago

By 500 million years ago, the Grenville Mountains wereeroded to their roots.

Laurentia(Proto-North America)

Grenville Province

IgneousPlutonsIgneous

Dykes Metamorphic gneiss, schist,quartzite, and marble The Supercontinent Rodinia

around 750 million years ago.

The oldest rocks in the Kingston area are the metamorphic and igneous rocks of the Grenville Province of the Canadian Shield. They started out as sediments in an ocean over 1.3 billion years ago, and they were metamorphosed during the formation of a supercontinent called Rodinia. The eroded roots of the mountain range that formed in this area due to continental collisions at that time underlie the entire Kingston region.

During the Cambrian and Ordovician Period, ocean levels were high on the Earth. Periodically during these times, North America was covered by water forming a distinctive sequence of rocks.

The geography of the Earth was quite different during the Ordovician, as shown by the paleogeographic reconstructions of Dr Ron Blakey of Northern Arizona University.

Water World: Kingston in the Ordovician

The Grenville Mountains of Kingston: 1.3 Billion Years Ago.

Ice Age: Kingston 18 000 years ago

The Earth’s climate began to cool dramatically around 1.6 million years ago. At least 4 times in the last one million years, the Kingston area has been completely covered by glacial ice. The last major ice sheet, the Wisconsin advance, covered this area until only about 10 000 years ago.

– Page 2–

Pacific Plate

North AmericanPlate

Indian-AustralianPlate

EurasianPlate Eurasian

Plate

AfricanPlateSouth American

Plate

Antarctic Plate

Cocos Plate

Nazca Plate

AtlanticMid-Ocean

Ridge

Oceanic Crust

Continental Crust

Island ArcVolcano

Trench Trench

“Hot Spot”Volcano

Continental Rift Zone(Newly-Forming Plate Boundary)

Mid-Ocean Ridge(Divergent Plate Margin)

Subduction Zone(Convergent Plate Margin)

“Hot Spot”

The movement of the plates is related to heat flow inside of the Earth. At mid-ocean ridges, underwater volcanoes add new ocean crust. At trenches, the ocean crust sinks down into the mantle again. “Hot spots” may be the cause of isolated volcanic island chains in the middle of the ocean (like the Hawaiian Islands).

Simplified Summary of Plate Tectonic Activity

Rising magmaadds new oceancrust at ridges

At subduction zones,the crust melts as it sinks back into the Earth again.

Field Trip Preparation: Plate Tectonics

Outline of the Major Tectonic Plates of the Earth

– Page 3–

2

3

4

6

5

1 Geology of KingstonField Trip RouteSeptember 2013 Version

LegendPALEOZOIC

ORDOVICIAN Period Sedimentary Rocks

Black River & Trenton GroupsLimestone.

Beekmantown GroupDolomite and sandstone.†

LOWER ORDOVICIAN OR CAMBRIAN Sedimentary

Potsdam or Nepean Formation

Sandstone.

PRECAMBRIAN

Granitic gneiss, migmatite, granitizedgneiss, hybrid granite gneiss, granitepegmatite.

Granite and syenite.

Grey granite, granite gneiss,granodiorite, tonalite.

Diorite, gabbro, anorthosite, meta-gabbro, amphibolite.

INTRUSIVE CONTACT

METASEDIMENTARY ROCKS (Metamorphic Rocks formed from Sediments)

Quartzite, quartzo-feldspathic rocks.

Paragneiss, pelitic and psammo-peliticschists and gneisses.

Marble, lime silicate rocks, skarn.

Para-amphibolite, biotite-amphiboleschists and gneisses.

13

12

11

10

9

8

7

5

4

3

2

UNCONFORMITY

Diabase or porphyritic andesite dikes.

PLUTONIC ROCKS (Igneous Rocks)

– Page 4–

Barriefield Hill Roadcut.Sea Level Rise.

– Page 5–

Stop #1

Barriefield Hill is a gentle limestone anticline - an arch made of dipping sedimentary layers which have the youngest layers at the top of the crest and the oldest layers in the core of the arch. An upside down arch with the oldest layers on the bottom is called a syncline.

One of the principles of stratigraphy (the study of sedimentary rock layers) says that sedimentary beds are originally deposited in flat, horizontal layers. So how did these layers become curved? Two possibilities exist: 1/ the flat layers were subjected to a force that folded or bent them; or 2/ the layers were deposited over a “bump” in the older basement rock and subsequent compaction over the basement high has accentuated the draping effect. There is evidence for both possibilities in this outcrop. In the south-side ditch halfway up the hill near the core of the anticline, there is an exposed “knob” of billion year old quartzite and gneiss. This resistant rock could be the basement high that the limestone layers draped over as mud was deposited from the seawater 470 million years ago. Since nothing is simple in geology however, there is evidence further up the hill (in the form of pressure-solution produced stylolites) that shows that there could have been pressure directed in an east-west sense that may have also slightly folded the sedimentary layers into the present anticlinal form.

Stylolites are surfaces in the rock where it has dissolved due to high directed pressure. When viewed from the side, the dissolutionsurface line resembles blocky “turret” shapesin the rock.

1 cm

Stylolites

Pressure Direction

Gentle Anticline

Quartzite/Gneiss Coreat the base of the anticline.

A mole-hill out of a mountain...Abbey Dawn Roadcut.

Stop #2

– Page 6 –

The oldest rocks in the Kingston area (the “basement rocks”) are approximately 1.1 billion year old metamorphic rocks of the Canadian Shield. They formed when our part of North America (Laurentia) collided with part of South America (Amazonia). The collision produced a Himalaya-scale mountain range called the Grenville Mountains running through this area around a billion years ago. Pre-existing sedimentary rocks were changed (metamorphosed) due to the heat and pressure: sedimentary limestone became metamorphic marble, sandstone became quartzite, and impure mixtures of mud and sand became gneiss.

As tectonic forces changed, the mountain-building pressures eased and weathering took over. By about 500 million years ago, the mountain range was completely eroded away leaving a barren rocky surface covered with sand, gravel and boulders. Land plants had not yet appeared on the Earth, and the land would have been bleak and barren. Harder rock ridges and knobs made up predominantly of quartzite would have been more resistant to erosion, and so some topographic relief would have been present in the area. Today, these resistant rocks are responsible for the area’s world famous 1000 Islands Region.

The outcrop at the Abbey Dawn Road illustrates beautifully the response of different rock types to erosion, and shows the sequence of events in the region between 1 billion and 500 million years ago. At the north end of the outcrop, the rock is a very resistant quartzite, which stands higher than the south end which is predominantly softer gneiss that more easily eroded away. At the very south end of the outcrop is a prominent angled layer of boulders, overlain by flat-lying layers of limestone from about 470 million years ago. The fact that the limestone beds are still horizontal indicates that it hasn’t been disturbed since being deposited as layers of mud on an ocean floor around 470 million years ago. This implies that the whole outcrop shows the original orientation of the rocks when sea levels rose. The quartzite to the north was a “hill” left over from the erosion of the Grenville Mountains. Boulders rolled down the hill to the south, creating a talus slope of angular boulders against the south slope of the hill. Finally, as sea levels rose, layers of lime mud were deposited against the boulder layer, eventually becoming limestone.

Since the quartzite and gneiss is around 1 billion years old, and the limestone is about 470 million years old, the 1-2 metre layer of boulders represents an erosional time gap (an unconformity) of at least 500 million years!

Undisturbed flat-lying limestone

Talus-slope boulder layer(conglomerate)

Gneiss (south end) nextto quartizite “hill” (north end)

500 million yearsof erosion!

Unconformity surface (a “non-conformity”)

Can you handle the pressure...Hwy 15 and Sunbury Road Roadcut.

Stop #3

Rivers flowing across a barren land...Sunbury Road.

– Page 7 –

During the mountain building episode, pre-existing limestone was metamorphosed to marble. Just as rocks respond differently to weathering (as seen at the Abbey Dawn roadcut) rocks also respond differently to the heat and pressure of metamorphism. In this outcrop, the marble behaved like wax, easily bending and flowing under the pressure. Pieces of brittle gneiss behaved differently, first folding and then breaking into pieces that are now seen “floating” in the surrounding marble.

Within the marble, grey-metallic grains of graphite can be found, which formed during the metamorphism from organic carbon that was buried in the original limestone.

Folded gneiss

Fragments of brittlegneiss surroundedby softer marble

The world of 500 million years ago was a much different place. Permanent land life had not yet appeared on the Earth (neither plants nor animals) and the continents were barren and wind-swept. Sands from the weathering of the Grenville Mountains would have been blown by winds, and washed by streams meandering across the landscape. Here, the sandstone is thinly bedded and cemented partially with the mineral hematite (red iron oxide) indicating that it was probably deposited on land in a river system. Pebble layers possibly indicate floods that winnowed away the finer sand, leaving only the heavier sediments. Other sandstones in the Kingston area were originally deposited in huge dunes, or on tidal-flat beaches near the slowly rising oceans from 470 million years ago.

Stop #4

Dykes and Plutons...Sunbury Road.

Stop #5

Crosscutting RelationshipsInverary.

Stop #6

Fault MovementDyk

e

Dyke

Limestone

Rideau Grit (Arkose Sandstone)

Precambrian Quartzite/Gneiss

Number the rocks and the from oldest (1) to youngest (7) on thisschematic diagram of the outcrop.

events

Sketch a normal fault and a reverse fault.

Nonconformity ( )Erosion

Disconformity ( )Sea Level Rise

– Page 8 –

In addition to metamorphism, the mountain building episode was accompanied by volcanism as well. Cracks opened up by the pressures of continental collision were filled with hot magma from below. At this outcrop, black basaltic magma filled cracks in the white quartzite forming numerous diabase dykes cutting through the rock.

At the west end of the outcrop, a larger intrusive white granite can be found. Even larger intrusions (plutons) of pink granitic rock can be seen throughout the area, forming features such as Foley Mountain in Westport, Ontario.

Black diabase dyke in white quartzite