Midterm: Environmental Geology Cont.1 Flashcards
This refers to the amount of biologically productive land/sea area needed to support the lifestyle of human beings
Ecological Footprint
Based on the standards set by PHIVOLCS, permanent structures must be at least _ meters awat from a known lineament/active fault.
5 meters
Between what geologic era was the Chicxulub Impact Crater in Yucatan Peninsula , Mexico formed?
Mesozoic to Cenozoic
these are pentagonal/hexagonal volcanic features that are formed through rapid cooling of lava (usually mafic in composition) and subsequent formation of shrinkage cracks.
Columnar Joints
average thickness of oceanic crust
5-7 km
it is a process involving dislodgement and subsequent incorporation of country rock to the upwelling magma
stoping
what feature is formed when incorporated country rocks survive melthing in the upwelling magma?
xenolith
these are low angle faults (<30 degrees) characterized by upward movement of the hanging wall relative to the footwall.
thrust faults?
An alert level _ is issued by Phivolcs if there is low to moderate seismic activity. Volcanic unrest is probably magmatic in origin and could eventually lead to eruption.
Level 2
palm structures (positive flower structures) are formed through what mechanism?
transpression
it is the point in the orbit of the moon or a satellite at which it is furthest from the Earth
Apogee
alternate term for left-lateral strike-slip faults
sinistral fault
the Philippine Fault Zone accommodates the stress created by the subduction of the Philippine Sea Plate beneath the Philippone Mobile Belt. It has an average length of_ and is classified as a _.
1200 km ; left lateral fault
what specific volcanic hazard is responsible for the casualties of the 79 AD Mt. Vesuvius eruption in Pompeii, Italy
Pyroclastic Flow
these are volcanic conduits that manly expel carbon dioxide into the Earth’s atmosphere
mofette
a lava flow that exhibits rough and splintery texture
aa lava flow
what volcano erupted in 1815 and resulted a maximum of 3 degrees Celsius drop in temperature. this particular event was also dubbed as “the year without summer”
Mount Tambora
it is a specific type of stony meteorite containing 75-90% silicon based minerals, 10-25% nickel-iron alloy, and trace amounts of iron sulfide. it contains nearly spherical silicate-rich particles
chondrite
this refers to the paper record of the Earth’s vibration. particularly, it is the medium where the arrival of seismic waves are plotted
seismogram
these are relatively stable, and broad interior parts of ancient contintents that are composed of crystalline basement rocks
Craton
Magnitudee 1 earthquakes release _ times less energy compared to magnitude 4 earthquakes
82,000 (?)
identify the (1) class of the earthquake based on the given magnitude and (2) classification based on the depth to focus, respsectively: Magnitude=6.5 ; Depth= 77 km below ground level
Strong
These are low angle reverse fault
thrust fault
the point directly below the epicenter is called as
hypocenter
it is the process involving movement of magma towards the Earth’s surface
volcanism
it is a property of an earth material to go back to its original shape once the stress is removed. however, earth materials have specific thresholds for this property.
elastic
average density of the earth is
5513 kg/m^3
mean density (NASA)
the climatic conditions in the Philippines favor relatively fast weathering and erosion rates of landforms. technically, climate as defined by PAGASA is the average weather condition for _ years
30 years
these are seismic waves that move the ground from side to side in a horizontal plane, but at right angles to the direction of propagation.
love waves (surface waves)
a term referring to a collection or network of components that interact and affect one another.
system
This had been the long-accepted theory since 15 AD which explains the relative position of celestial bodies in the solar system i.e., Sun is located at the core of the solar system
Heliocentric Model
True or False.
Volcanic activity may be correlated to the electrial resistivity of subsurface materials. Particularly, continued upwelling of magma causes fracturing of overlying rocksm thereby causing electrical resistivity of near surface rocks to decrease relative to its normal value.
True
True or False.
The minimum permanent danger zone of active volcanoes in the Philippines, as set by PHIVOLCS, is 3 kilometers
False ; 6km
True or False
The Earth has* seven major tectonic plates*
True
true or false
Passive contintental margins are also called Antarctic type margin as they possess relief features such as contintental shelf, continental slope, and continental rise, all are formed away from subduction zones
False ; Atlantic
true or false
If a star is massive, during the end of its life, it explodes and forms a neutron star where light nor matter cannot escape
False ; black hole
true or false
the principal/maximum stress acting along the Philippine Fault Zone is oriented vertical downward relative to the two shearing fault blocks.
False ; horizontaly perpendicular
true or false
This marks the seismic anomaly existing between the lower crust and upper mantle
Mohorovicic Discontinuity
usually formed due to oceanic-oceanic convergence
volcanic island arc
generally occur when contintents or island arcs crash into one other, but tend to resist subduction
collision
true or false
ground shaking and magnitude are directly correlated
True
true or false
joints and faults are generally considered as fractures
true
true or false
The Mount Apo is classified as a dormant/potentially active volcano based on PHIVOLCS classification
false ; potentially active
this will occur if the natural vibration frequency or period of a manmade structure matches that of an earthquake
Resonance
PHIVOLCS Earthquake ranges from? with the last scale classified as completely devastating
I - X
