Geologic Time
The era of "visible life", encompassing the last ~550 million years.
What is the Phanerozoic?
This type of volcano has low viscosity lava, usually lava flows as the main hazard, and gently sloping sides over a large area.
What is a shield volcano?
The point on the Earth's surface, closest to where an earthquake occurred.
What is an epicenter?
This type of landslide usually involves hard rocks, occurs on very steep slopes, and is driven by gravity.
What is rock fall?
The lack of what defines a desert?
What is precipitation?
The "Age of Dinosaurs", with three sub ages.
What is the Mesozoic?
This type of volcanic hazard is incredibly fast moving, is a mix of ash, gas, and other debris, and is responsible for tragedies such as Pompeii.
What is a pyroclastic flow?
The physical point where as earthquake occurred on a fault, often deep underground.
What is a hypocenter?
A glacier is defined by, and differs from a permanent snow or ice field in this way.
What is moves?
The most common cause of a tsunami.
What is an earthquake?
The last period of time in the Precambrian (era prior to the Phanerozoic), named for mysterious fossils.
What is the Ediacaran?
This type of volcanic hazard is characterized by my water or melted snow and ice mixed with ash, gas, soil, and volcanic debris, and can travel great distances following river channels.
What is a lahar?
These compressional waves, rather that the undulating shaking waves, are the first to arrive in an earthquake.
What are p-waves?
A type of landslide that is very fast moving, incorporates water, soil, rocks, a hazard in the greater LA area.
What is a debris flow?
The highest and lowest point of a wave are known respectively as.
What is the crest and trough?
This Paleozoic animal lived in the oceans, had a long straight shell, and a squid-like animal living inside that shell.
What is a nautiloid?
Knowing that Mt. St Helen's had an explosive eruption in 1980, what prediction could you make about the relatively high or low silica content in the magma?
What is high silica content?
Books falling over on a bookshelf are an example of this type of fault.
What is a normal fault?
A very slow moving type of landslide, mostly responsible for curved tree trunks and fences tilting downhill.
What is creep?
A layer of impermeable clay in the earth's subsurface, with groundwater trapped below is this type of aquifer.
What is a confined aquifer?
This time period is marked by the largest mass extinction of all time, when ~99% of all species on Earth went extinct.
What is the Permian?
About how much ash is needed to start collapsing roofs on human habitation?
What is 2cm?
Which type of earthquake wave can travel through the liquid core?
What is p-waves?
The gravel deposits left at the toe of a glacier.
What is a moraine?
When a tsunami reaches shallow water near shore, this happens to the wavelength and to the speed.
What is shortens and slows?