From the Beginning
Approx. 600 + million years ago on the South Pole there was a large continent that Geologists call Amazonia. Erosion of the highlands of this continent carried sediment out to the ocean and eventually built up deep layers of sedimentary rock (sandstone) over hundreds of square miles on the continental shelf. Now we have what’s called a Terrane. Terrane is the name given to things like volcanic Islands, Sea Mountains and sedimentary basins that stand alone in an ocean. When a continent moves across an ocean these terranes are scraped off of the ocean floor & pushed along with the bigger continent.
When the continent of Amazonia began to drift northward, the Terrane was scrapped off the ocean floor and was pushed along by the big continent. This Terrane is known as the Miramichi-Bras d’Or Terrane. As it was pushed along, its sediments were infiltrated by molten rock from deep with in the earths crust. This liquid rock pushed its way up through the sandstones & other sediments, causing molten rock to flow out over the surface of the Terrane in many places. This was caused by pressures that are associated with the moving of continents.
Now we have a Terrane made originally of sandstones, partly covered with molten rock. At this point most of the original sediments (sandstones) were altered, or changed in to much harder rock from the heat & pressure provided by the molten rock.
At the same time the Miramichi terrane was being deposited , There was another terrane being built up in a different ocean. The Avalon terrane was of volcanic origin. Geologists figure the Avalon terrane was dominated by huge volcanoes, similar in size to Mount St. Helens. Rocks from the Avalon have been dated from 550 to 740 Million years. The Miramichi Bras d’Or terrane was formed near the coast of the former Continent Amazonia, which now makes up present day South America. The Avalon Terrane was formed off the coast of the former continent ProntaGondwana which makes up present day Africa
About 350 to 400 million years ago all of the continents and terranes on earth assembled in to one big super Continent (Pangea) surrounded by one super ocean.
The Miramiche Bras d’or & Avalon terranes ended up together and sandwiched between big continents, (along with several other terranes). Former oceans closed as the continents met, and one of the biggest mountain chains on earth was formed as the continents collided with each other. The Appalachians may have been as high as the modern Himalayas. They stretched from Alabama to Europe. (The Atlantic Ocean did not yet exist).
The region that would later become the Maritimes was now pretty much in tact. We had drifted from near the south pole to the equator & were deep within the super continent Pangea, no where near the ocean.
As the mountain building continued there were also deep depressions developing in the maritime region.
At one point sea levels rose & sea waters invaded the region about 330 million years ago. This lasted about 15 million years and when it was over there were large deposits of salt , potash & gypsum left behind from the evaporation of this sea. Windsor Sea. (hence the name Windsor salt.)
Salt deposits from this episode lie deep beneath Queens & Kings County’s.
Most of Prince County is thought to have been above sea level during the time of the Windsor sea.
315 Million Years Ago
The beginning of the final episode for what was to become PEI. The Appalachians were eroding away, the sediment carried down stream by huge fresh water rivers and deposited in the lowlands as the rivers lost there momentum. The Caladonia hills of N.B. & the Cobiquid Mountains of N.S. also supplied sediment to parts of PEI.
90 Million Years Ago
The next 40 million years would build up sediments from 8,000 to 30,000 feet thick on top of parts of the Miramiche Bras d’Or & Avalon terranes .
Desert conditions were the norm with sand dunes similar to the present day Sahara during the dry season & floods in the rainy season. (Referred to as the Mega Monsoons.)
248 Million Years Ago
PEI is now pretty much intact. Still near the equator & still far from any ocean. This huge pile of sediments had already started its transition from soft sediments to sedimentary rock.
Remember that large layers of salt lie beneath many parts of queens & kings county. The weight of the sediments on top of the salt caused the salt to form diapers, and these salt diapers would push the bedrock upward in some places. Some of the hills in Queens & kings were formed in this way.
Other hills were formed by a process called folding. This is when a particular spot on the earths crust comes under pressure, for whatever reason, and simply pushes the bedrock up in one place. Usually in a line causing a row of hills. At least 5 different folds have been identified on PEI.
100 To 200 Million Years Ago
The Supercontinent is breaking up into pieces. A crack thru the region turns into a valley and continues to open into what is now the North Atlantic Ocean.
About 100 million years ago Europe & Newfoundland were split and the continents drifted to our present position at a rate of approx. an inch or two per year. The Merimiche Bras d’Or & Avalon terranes were split in two in the process.
Prince County & western Queens County are underlain by the Merimiche Brad or terrane. Also the east end of PEI, from east point toward the west for about 40 or 50 Kilometres, is underlain by the Merimiche Brador Terrane .
Therefore it could be argued that Summerside & Tignish and East point are an ancient part of South America.
Most of Queens and Kings County are underlain by the Avalon Terrane and it could be argued that Charlottetown and Wood Islands are an ancient part of Africa.
The boundary where the Miramiche Bras d’Or terrane meets the Avalon terrane can be seen at the Reversing Falls Bridge in St. John NB.
Most of this information was taken from a book written by the Atlantic Geoscience Society. The Last Billion Years.
Other sources are Understanding Earth, a Dalhousie text book & The Changing Earth, Former Dalhousie text book, written by Clinton Milligan. Clinton is from Tyne Valley PEI.
PEI Bedrock
The bedrock on PEI began to form roughly 300 million years ago and was pretty much completed about 250 million years ago. Throughout this time the Maritimes were not a coastal region, but were far inland within the former Super Continent (Pangea), at or near the equator.
When the bedrock of PEI was being formed, it was a desert, complete with sand dunes in the dry seasons and floods in the wet seasons. (Scientists believe that the greatest mass extinction of life also took place approx. 250 million years ago when 90% of all species in the oceans perished, and on land 60% of the reptiles and 30% of the insects disappeared.)
Underneath Queens and kings county bedrock lies large salt deposits, left behind by the evaporation of an ancient ocean (the Windsor sea).
One of the events that led up to the building of P.E.I. started about 380 million years ago. Around this time two continents had collided together. The ocean that separated them, the lapetus, was closed off, and as the continents met they formed what was then the highest mountain chain on earth, the Appalachian's. Similar to the modern Himalaya. Much of our P.E.I bedrock was formed as huge rivers carried sediment down from these mountains and deposited it in the lowlands.
In some areas,( Irishtown & Governors Island) the bedrock reaches depths of 14,000 feet. The bedrock in Southeastern PEI is estimated to be 30,000 feet deep. Samples taken from deep bore holes indicate plant and animal life did exist here over the ages, including dinosaurs.
The speed at which the rivers ran determined what size of sediment they were capable of carrying with them. As a river would lose its speed, it would deposit finer material, which would become a clay or silt stone.
These layers of claystone play an important roll in PEI ground water. They deflect migrating ground water and act as horizontal partitions within an aquifer. The ground water above and below these claystone partitions can be of different ages, and quality. The water above the layer of claystone probably entered the ground locally, whereas the water below the claystone layer probably entered the ground at a point up hill and beyond the lateral extention of the claystone layer.
When oil companies do seismic work prior to drilling, they look for claystone layers to act as oil and gas traps. If the clay/silt stone layer is cracked then the oil or gas may have escaped to the atmosphere millions of years ago. This is one of the reasons that drilling for oil or gas, at best has a 90 % risk of failure.
There were so many rivers over such a long period of time, depositing fine and course sediment in different directions, that it is practically impossible to follow any one ancient river for any distance. This makes well drilling a real challenge as the rock formation can change dramatically in a very short distance, as can water quality and quantity. ( See The Ice Age & PEI and Ancient Geological History of PEI)
The Ice Age & PEI
When the last of the Glaciers melted back toward the north approx. 10,000 years ago, it left PEI covered in a blanket of loose till. This makes it hard for Geologists to say with any certainty, what kind of bedrock lies under any one spot, without actually drilling down to it
The type of till that was deposited by the melting ice influences both the quantity and quality of PEI ground water.
For example: If the ice melts in place, as stagnant ice, and the debris was dropped in a pile. Then water spent a longer time getting through the fine sediments and reaching the bedrock. If there were active rivers and streams which sorted out the sediment from course sand to fine sand to clay. The area with course sand would then allow water to pass through to the bedrock almost immediately, with little or no filtering, but allowing large volumes of a poorer quality water to reach bedrock.
It is thought that much of the ice that covered PEI came from Labrador. And when it melted, PEI rose up at least 75 feet when the weight of the ice was gone.
The largest rock ever recorded to have been moved by a glacier was in Germany. The rock was 4 km. long, 2 km wide & 120 meters high.
During the 3 million years of ice advances and retreats the sea levels rose and fell as much as 460 feet.
Approx. 600 + million years ago on the South Pole there was a large continent that Geologists call Amazonia. Erosion of the highlands of this continent carried sediment out to the ocean and eventually built up deep layers of sedimentary rock (sandstone) over hundreds of square miles on the continental shelf. Now we have what’s called a Terrane. Terrane is the name given to things like volcanic Islands, Sea Mountains and sedimentary basins that stand alone in an ocean. When a continent moves across an ocean these terranes are scraped off of the ocean floor & pushed along with the bigger continent.
When the continent of Amazonia began to drift northward, the Terrane was scrapped off the ocean floor and was pushed along by the big continent. This Terrane is known as the Miramichi-Bras d’Or Terrane. As it was pushed along, its sediments were infiltrated by molten rock from deep with in the earths crust. This liquid rock pushed its way up through the sandstones & other sediments, causing molten rock to flow out over the surface of the Terrane in many places. This was caused by pressures that are associated with the moving of continents.
Now we have a Terrane made originally of sandstones, partly covered with molten rock. At this point most of the original sediments (sandstones) were altered, or changed in to much harder rock from the heat & pressure provided by the molten rock.
At the same time the Miramichi terrane was being deposited , There was another terrane being built up in a different ocean. The Avalon terrane was of volcanic origin. Geologists figure the Avalon terrane was dominated by huge volcanoes, similar in size to Mount St. Helens. Rocks from the Avalon have been dated from 550 to 740 Million years. The Miramichi Bras d’Or terrane was formed near the coast of the former Continent Amazonia, which now makes up present day South America. The Avalon Terrane was formed off the coast of the former continent ProntaGondwana which makes up present day Africa
About 350 to 400 million years ago all of the continents and terranes on earth assembled in to one big super Continent (Pangea) surrounded by one super ocean.
The Miramiche Bras d’or & Avalon terranes ended up together and sandwiched between big continents, (along with several other terranes). Former oceans closed as the continents met, and one of the biggest mountain chains on earth was formed as the continents collided with each other. The Appalachians may have been as high as the modern Himalayas. They stretched from Alabama to Europe. (The Atlantic Ocean did not yet exist).
The region that would later become the Maritimes was now pretty much in tact. We had drifted from near the south pole to the equator & were deep within the super continent Pangea, no where near the ocean.
As the mountain building continued there were also deep depressions developing in the maritime region.
At one point sea levels rose & sea waters invaded the region about 330 million years ago. This lasted about 15 million years and when it was over there were large deposits of salt , potash & gypsum left behind from the evaporation of this sea. Windsor Sea. (hence the name Windsor salt.)
Salt deposits from this episode lie deep beneath Queens & Kings County’s.
Most of Prince County is thought to have been above sea level during the time of the Windsor sea.
315 Million Years Ago
The beginning of the final episode for what was to become PEI. The Appalachians were eroding away, the sediment carried down stream by huge fresh water rivers and deposited in the lowlands as the rivers lost there momentum. The Caladonia hills of N.B. & the Cobiquid Mountains of N.S. also supplied sediment to parts of PEI.
90 Million Years Ago
The next 40 million years would build up sediments from 8,000 to 30,000 feet thick on top of parts of the Miramiche Bras d’Or & Avalon terranes .
Desert conditions were the norm with sand dunes similar to the present day Sahara during the dry season & floods in the rainy season. (Referred to as the Mega Monsoons.)
248 Million Years Ago
PEI is now pretty much intact. Still near the equator & still far from any ocean. This huge pile of sediments had already started its transition from soft sediments to sedimentary rock.
Remember that large layers of salt lie beneath many parts of queens & kings county. The weight of the sediments on top of the salt caused the salt to form diapers, and these salt diapers would push the bedrock upward in some places. Some of the hills in Queens & kings were formed in this way.
Other hills were formed by a process called folding. This is when a particular spot on the earths crust comes under pressure, for whatever reason, and simply pushes the bedrock up in one place. Usually in a line causing a row of hills. At least 5 different folds have been identified on PEI.
100 To 200 Million Years Ago
The Supercontinent is breaking up into pieces. A crack thru the region turns into a valley and continues to open into what is now the North Atlantic Ocean.
About 100 million years ago Europe & Newfoundland were split and the continents drifted to our present position at a rate of approx. an inch or two per year. The Merimiche Bras d’Or & Avalon terranes were split in two in the process.
Prince County & western Queens County are underlain by the Merimiche Brad or terrane. Also the east end of PEI, from east point toward the west for about 40 or 50 Kilometres, is underlain by the Merimiche Brador Terrane .
Therefore it could be argued that Summerside & Tignish and East point are an ancient part of South America.
Most of Queens and Kings County are underlain by the Avalon Terrane and it could be argued that Charlottetown and Wood Islands are an ancient part of Africa.
The boundary where the Miramiche Bras d’Or terrane meets the Avalon terrane can be seen at the Reversing Falls Bridge in St. John NB.
Most of this information was taken from a book written by the Atlantic Geoscience Society. The Last Billion Years.
Other sources are Understanding Earth, a Dalhousie text book & The Changing Earth, Former Dalhousie text book, written by Clinton Milligan. Clinton is from Tyne Valley PEI.
PEI Bedrock
The bedrock on PEI began to form roughly 300 million years ago and was pretty much completed about 250 million years ago. Throughout this time the Maritimes were not a coastal region, but were far inland within the former Super Continent (Pangea), at or near the equator.
When the bedrock of PEI was being formed, it was a desert, complete with sand dunes in the dry seasons and floods in the wet seasons. (Scientists believe that the greatest mass extinction of life also took place approx. 250 million years ago when 90% of all species in the oceans perished, and on land 60% of the reptiles and 30% of the insects disappeared.)
Underneath Queens and kings county bedrock lies large salt deposits, left behind by the evaporation of an ancient ocean (the Windsor sea).
One of the events that led up to the building of P.E.I. started about 380 million years ago. Around this time two continents had collided together. The ocean that separated them, the lapetus, was closed off, and as the continents met they formed what was then the highest mountain chain on earth, the Appalachian's. Similar to the modern Himalaya. Much of our P.E.I bedrock was formed as huge rivers carried sediment down from these mountains and deposited it in the lowlands.
In some areas,( Irishtown & Governors Island) the bedrock reaches depths of 14,000 feet. The bedrock in Southeastern PEI is estimated to be 30,000 feet deep. Samples taken from deep bore holes indicate plant and animal life did exist here over the ages, including dinosaurs.
The speed at which the rivers ran determined what size of sediment they were capable of carrying with them. As a river would lose its speed, it would deposit finer material, which would become a clay or silt stone.
These layers of claystone play an important roll in PEI ground water. They deflect migrating ground water and act as horizontal partitions within an aquifer. The ground water above and below these claystone partitions can be of different ages, and quality. The water above the layer of claystone probably entered the ground locally, whereas the water below the claystone layer probably entered the ground at a point up hill and beyond the lateral extention of the claystone layer.
When oil companies do seismic work prior to drilling, they look for claystone layers to act as oil and gas traps. If the clay/silt stone layer is cracked then the oil or gas may have escaped to the atmosphere millions of years ago. This is one of the reasons that drilling for oil or gas, at best has a 90 % risk of failure.
There were so many rivers over such a long period of time, depositing fine and course sediment in different directions, that it is practically impossible to follow any one ancient river for any distance. This makes well drilling a real challenge as the rock formation can change dramatically in a very short distance, as can water quality and quantity. ( See The Ice Age & PEI and Ancient Geological History of PEI)
The Ice Age & PEI
When the last of the Glaciers melted back toward the north approx. 10,000 years ago, it left PEI covered in a blanket of loose till. This makes it hard for Geologists to say with any certainty, what kind of bedrock lies under any one spot, without actually drilling down to it
The type of till that was deposited by the melting ice influences both the quantity and quality of PEI ground water.
For example: If the ice melts in place, as stagnant ice, and the debris was dropped in a pile. Then water spent a longer time getting through the fine sediments and reaching the bedrock. If there were active rivers and streams which sorted out the sediment from course sand to fine sand to clay. The area with course sand would then allow water to pass through to the bedrock almost immediately, with little or no filtering, but allowing large volumes of a poorer quality water to reach bedrock.
It is thought that much of the ice that covered PEI came from Labrador. And when it melted, PEI rose up at least 75 feet when the weight of the ice was gone.
The largest rock ever recorded to have been moved by a glacier was in Germany. The rock was 4 km. long, 2 km wide & 120 meters high.
During the 3 million years of ice advances and retreats the sea levels rose and fell as much as 460 feet.