G10 Tectonic Plates Flashcards
Blocks that are primarily sturdy, with margins that trace earthquake zones lying along the network of ridges and trenches
Tectonic Plates
Models for Plate Movement
Kinematics and Dynamics
structures are examined and compared to the movements of blocks of Earth’s surface, ignoring underlying forces.
Kinematics
forces and processes resulting in material movement throughout Earth
Dynamics
is the continental drift hypothesis and seafloor spreading hypothesis combined.
Plate Tectonic Theory
Argues close kinship among sets of continents, as well as their geological characteristics.
Continental Drift Theory
The Earth’s ancient supercontinent
Pangaea
Explains the formation of new oceanic crust which leads to the movement of plates.
Seafloor Spreading
There are only seven major plates which include
North America, South America, Pacific, African, Eurasian, Australian-Indian, and Antarctic plates.
Factors Affecting Plate Movements
Solid-state flow model, Hotspots
Relies on temperature and phase changes.
Solid-state flow model
Areas with abnormally high volcanic activity hat have remained stationary for a very long time.
Hotspot
radioactivity causes magma to rise where it expands to produce the plates above Earth’s surface.
Solid-State Flow Model
The _, _ plates descend, replacing the hotter material below.
Can be likened to a kettle.
(Solid-State Flow Model)
older, denser
gravitational factors
ridge push, slab pull
This is a force that causes hotter, less dense material to force itself up through a ridge.
Ridge push
This is the pulling of oceanic lithosphere downward at subduction zones.
Slab pull
3 main processes that affect mantle convection
heating at the bottom caused by the heat loss from Earth’s core.
heating due to radioactive decay
cooling on the surface creating thick, cold lithospheric slabs denser than the mantle.
is the supercontinent of ancient Earth.
Pangaea
The northern landmass was
Pangaea
Laurasia
The southern landmass(Pangaea)
Gondwana
Evidence that Supports Plate Movement
Continental Fit, Fossil Evidence, Paleomagnetic Data,
Some continents’ shapes fit each other.
Scientists believe, with evidence, that these continents were once connected to each other.
Continental Fit
can be found in separate continents even though they are from the same species.
Fossils of animals and plants
Fossil evidence
Specific deposits also provide _ _ _ in conditions across continents.
(Fossil Evidence)
evidences of similarities
a series of rock deposits that provides evidence for these assemblages
(Fossil Evidence)
Gondwana Rock Succession
has an influence of patterns in rocks, which coincide with shifts in the _ _ _
(Paleomagnetic Data)
Earth’s magnetic pole
The Earth’s magnetic pole has an influence of patterns in rocks, which coincide with shifts in the Earth’s magnetic pole.
This serves as evidence because their magnetic north was found to be _.
discordant
Can rock patterns be founf in Reykjanes Ridge?
Yes
implications of Plate Tectonics
rate of plate movements, geologic history of localities, mineral explorations, hazard predictions, and urban planning
Plate tectonics elucidates the geologic history of localities by providing an explanation for the regional settings and processes of an area, painting a more vivid picture of the geologic record.
(Geologic History)
-
As a result of tracing an area’s geologic history, mineral explorers
(Mineral Explorations)
can more easily trace and quantify deposits
Geologic maps show these features.
-
Most of the seismicity can be found
Hazard Prediction
along plate boundaries
Studying these boundaries can allow humans to
Hazard Prediction
predict any hazards within the area.
Only _ was connected to other landmasses in the past.
The rest of the Philippines emerged from the ocean.
Palawan
Other crustal movements that are not related to seismic activities.
These are usually less intense compared to seismic activity.
Aseismic Activity
As a result of hazard predictions, humans can also properly plan the arrangement of urban settlements.
Urban Planning
Institutes in the Philippines that study seismology
DOST, PHIVOLCS
DOST
The Department of Science and Technology
PHIVOLCS
The Philippine Institute of Volcanology and Seismology, an arm of DOST.
Fossil assemblages among the continents possess differences, indicating that the fossilized organisms had to have crossed the continents via _ _.
land bridges
is a specific temperature at which materials change or lose their magnetism
Curie point
is not static, rather, it frequently switches polarities. These changes are referred to as magnetic reversals.
Earth’s magnetic field
Earth’s magnetic field frequently switches polarities. These changes are referred to as
magnetic reversals
Plates move extremely slowly most of the time for extended periods of time. This slow movement is referred to as
creep
Crustal movements having less intensity than those related to tectonic belts are classified as
aseismic
is in charge of reducing the impacts of natural disasters.
Philippine Institute of Volcanology and Seismology (PHIVOLCS)
developed,
was widely advocated by Alfred
Wegener in 1915.
Continental Drift Theory
developed,
was widely advocated by Alfred
Wegener in 1915.
Continental Drift Theory
In 1962, Harry Hess pioneered the concept of
seafloor spreading
a specific
point
where three plate boundaries converge
triple junction
arm of the triple junction that failed to
produce an ocean basin, it is referred to as an
aulacogen
In the 1930s, Arthur
Holmes
heavily
advocated
solid-state flow model
moves material underneath the plates
sideward, but its effect is so small that it is considered negligible
Mantle drag
are rising columns of hot
rocks from the lower mantle and cause
melting as they reach the surface, hence
another mechanism for plate motion
Mantle plumes
mantle is divided into two zones of
convection which is a thin layer in the upper mantle at a depth of 660 kilometers
and a thick layer located below. This model is known as
layer cake model
where denser oceanic
lithosphere sinks and may even reach the core-mantle boundary. This material
eventually melts and rises toward the surface of Earth.
whole mantle convection
indicate a large ice sheet encompassing broad areas of
today’s southern continents
Glacial deposits
marked an
ancient desert
evaporites and sandstones
rates of continental advancement and seafloor spreading are determined by
measuring the _ _ _ _ _ _ _ _. In fact, the locations
of the continents prior to Pangaea’s breakup were also accurately pinpointed
through this method
widths of the magnetic stripes on the seafloor
rates of continental advancement and seafloor spreading are determined by
measuring the
widths of the magnetic stripes on the seafloor
oceanic plate’s speed
6-9cm
oceanic plate’s speed
6-9cm/year
continental plate’s speed
2 cm/year
elucidates the geologic history of localities by providing an
explanation for the regional settings and processes of an area, painting a more
vivid picture of the geologic record
Plate tectonics
an essential material in
mineral explorations. It provides various
information that is important in locating for new mineral deposits. It makes use of the morphology of rocks bodies as well as age relationships between rock units.
geologic map
use surface modifications that are being recorded with time which can be used to make three or four-dimensional geologic models.
Tectonic processes
areas where
settlements must not be built
permanent danger zones
