Thursday, September 13, 2012

The Rising of South America, Part VIII—Barely Above Sea Level


Brazilian Highlands—mostly the Mato Grosso plateau in the southern part of the country, covers a large swatch of the landscape with its synclines (concave upward folds) and anticlines (concave downward folds) emerging among cerrado vegetation (savanna) that covers a fifth of the country. The Brazilian Highland plateaus in the southern part of the country are notable for their beauty.
Brazil Highlands, an eroded plateau region of central and southeastern Brazil, rising to an average of 3,300 feet above sea level, and characterized by low mountains, hilly uplands, and tabular plateaus
However, it is the lowland basins that mark the upper South American continent’s interior. There are over 350 known drainage basins all over the world with the three largest ones being the Mississippi, Congo and the Amazon. The river that drains the largest amount of water from the largest drainage basin–the Amazon Drainage Basin–is the Amazon river. This drainage basin, combined with more than a dozen other major drainage basins in South America cover millions of square miles of relatively flat, swampy, and flooded wetlands, catchment lowlands, and moist forests.
While drainage basins are essential and definitely necessary, the Amazon Draining Basin is quite different from most others. First of all, the basin sits very close to sea level throughout its 2.7 million square miles, as do other nearby draining systems of South America (see the earlier post).
The problem this creates is seen in the difficulty of people living within the Basin area. The Amazon River, and its numerous tributaries, overflow during the wet season that lasts about six months of the year. This is not an occasional occurrence, like the flooding of the Mississippi River—but an annual event that is both predictable and well understood. During these floodings, the Amazon River water level and its surrounding basin area rises between thirty and forty feet. When we consider that the entire Amazon Basin drops only about 400 feet in 4000 miles, we see how a slight rise can effect hundreds, even thousands of square miles. As a result, people living within the Basin are faced with building houses that can handle such changes in water level and flooding.
Floating houses along the Amazon at Iquitos, Peru, the largest city in the Peruvian rainforest, it is the most populous city in the world that cannot be reached by road

In Iquitos, Peru, where the Amazon begins its nearly level flow from 348 feet to the Atlantic Ocean 3400 miles away, houses are built to float on the water so when it rises, the houses move upward naturally. It rains here all year round and Iquitos becomes an island during the really heavy rainy season, surrounded on three sides by rising waters of the rivers and the flood plain.

At high tide some houses are built around pylons that allow them to move up an down as the flood level changes
A peculiarity of the Brazilâs Amazon is the lack of settlements along the river's banks, compared to the usual large ports, transport networks and industrialized cities found along important waterways. Among the only three sizable cities settled on the Amazon banks are Iquitos in Peru at the beginning of the Basin, and Manaus about in the middle and Belen at its mouth.
In the Basin, the forest areas are described by amount of flooding that occurs: 1) not flooded, 2) occasionally flooded, or 3) regularly flooded, and houses built off the water or away from the rivers, are built on stilts for when the river rises 30 or 40 feet in height

Even houses built off the water or some distance inland are flooded during the wet season for about five to six months and are built on stilts to keep them above the water line when it floods
When the Basin is flooded, there is nowhere to go unless you have a dugout canoe, which 90% of the travel by locals is by small boat--very old and rickety open boats which leak and require constant bailing to keep afloat, often by mothers holding babies with little kids.
With so much water it is not unusual that the main mode of transportation throughout the area is by boat. The smallest and most common boats used today are still made out of hollowed tree trunks, whether they are powered by outboard motors or more often by man-powered paddles. Almost 14,000 miles of Amazon waterway are navigable and several million miles through swamps and forests are penetrable by canoe. The enormous Amazon River carries massive amounts of silt from run-off from the rainforest floor. Massive amounts of silt deposited at the mouth of the Amazon river has created the largest river island in the world, Marajo Island, which is roughly the size of Switzerland. 
Houses that are built in the lowlands far away from the river are still flooded when the water rises throughout the Basin.
Top Pics: These houses were built in the lowland plains far from the river, but the six month flood season isolates them on an inland sea; Bottom Left: It is wet so much of the year that the ground is typically muddy nearly all year long; Bottom Right: House built far from the river but during the wet season, it is at river’s edge
Some houses are built on logs directly on the water, with pylons anchored in the depths so the houses can ride up and down looped to the pylon when the water level rises and falls.
Some settlements are permanently built on the water since there is no way to get far enough above the flood line in many places to avoid the rising waters
The Amazon River, and the Basin surrounding it, slopes from Iquitos to Manaus, 906 miles distant, dropping only 204 feet, which is a drop of less than 3” every mile.
The city of Iquitos (nicknamed the Capital de la Amazolnia Peruana--Capital of the Peruvian Amazon) in the Andean (Peru) jungle is the first city along the Amazon River (known as the Gateway to the Amazon jungle) and is located at 343 feet elevation
From Manaus to the mouth of the Amazon is 2500 miles, with a drop of 144 feet in elevation, which is an elevation drop of 1” per 1.5 miles. So in over 3400 miles, the Amazon river and surrounding lowlands drop one inch per eight-tenths of a mile. The entire river and Basin drops only 1" per ¾ of a mile over a 4000 mile distance. This obviously shows that the entire 2.7 million square mile Amazon Drainage Basin, which averages a mere 300 feet above sea level is actually a true lowland basin. This is why the Basin is flooded six months out of the year, with floating houses along the waterways, or others built on poles for when the tides rise.
The city of Manaus along the Amazon sits at 144 feet above sea level, with numerous bustling boat docks which look more like bus stations along the floating docks of this city of approximately 2 million people, which has over a 1000 miles of forest in every direction around it
Believe it or not, there are even numerous huge floating fueling stations for the river/swamp traffic needing gasoline or propane fuel, in an area where water covers most of the earth around Manaus
For those who think they know South America and dismiss it out of hand as a location for the Land of Promise simply show their ignorance of the uniqueness of this land that is not only barely above sea level throughout much of its interior, but the entire continent tilts downward to the east as the western edge of the South American tectonic plate continues to rise above the subducting Nazca Plate. Within the Andean area can be found matches to every single description written by Mormon and other prophets who wrote about their land.
(See the next post, "Rising Lands Around the Globe," to see how islands are appearing from beneath the sea in different parts of the world in not so unique events)

No comments:

Post a Comment