Transcript Landscapes - Red Hook Central School District

Drainage Patterns, Landscapes of NY
and the Affects of Human Activites
 Rocks
that are durable resist
weathering and erosion
 Durable rocks form the higher
portions of a landscape (ex.
plateaus, mountains, and cliffs)
 Softer
rock erodes faster than
harder, durable rock
 If layers of a hill differ in
durability, the softer rocks
will wear away faster, giving
the hill an uneven or stepped
appearance
 Drainage
patterns are
determined by the way
tributaries join to form larger
streams
 Streams tend to follow zones
of weaker rock because they
erode into valleys

Dendritic/ Random: Develops in
horizontal rock layers with little
difference in resistance
 Rectangular/Trellis:
Observed in folded, faulted
and jointed rocks with much
difference in resistance

Radial- occurs on domed
landscapes with little difference
in resistance, like volcanoeslooks like spokes of a wheel

Annular: A pattern of concentric
circles found in areas of domed
structure with much difference
in rock resistance
Farming and construction
projects can increase erosion
 Contour plowing curves around
a hill, rather than up and down
the hillside, helping to slow
water runoff and erosion.

Strip mining removes layers of
soil to dig up minerals found in
bedrock.
 When finished, engineers can
even out the land, replace the
soil and add plants
 People move more soil and rock
than all rivers combined!




St. Lawrence/Champlain Lowlands: low-lying
plain along the St. Lawrence River and Lake
Champlain
Adirondack Mountains: only true mountain
region in NYS made up of resistant rocks
Appalachian Uplands: NY’s largest region that
is mostly flat layers of sedimentary rocks. Used
to be the bottom of an ocean, pushed up over
the years


The Finger Lakes: formed by a continental
glacier which deepened and widened preexisting valleys. As the glaciers melted, the till
blocked outlets to the south forming the lakes
The Erie-Ontario Lowlands: lie south of the
Great Lakes with NY borders. Although it is a
plains landscape, these lowlands have many
hills composed of unsorted glacial till. Good
soil, deposited and mixed by glaciers, and a
climate moderated by the lakes makes this an
important agricultural area



Tug Hill Plateau: small region of elevated
sedimentary rock layers. Poor drainage caused
by glacial deposits and abundant winter
snowfall make this one of the least-inhabited
areas in the state
Hudson-Mohawk Lowlands/Plains: Follows a
zone of easily eroded limestones and shales
New England Highlands: a region of intensely
folded and faulted metamorphic rocks.


Triassic Lowlands: a section of sandstones and
shales deposited in a fault basin. This region is
geologically younger than the surrounding
highlands. An intrusion of basaltic magma was
eroded by the Hudson River, forming the high
cliffs of the Palisades.
Atlantic Coastal Plain: largely composed of
glacial sediments. The land south of the
moraines of LI is composed of sorted material
wasted out of glaciers.