uwo geo 2152 - missed terms

• causes of climate change: variation in sun's radiation, changes in composition of atmosphere, changes in earth's surface, variations in earth's orbit
• eccentricity: changes in earth's orbit from circular to elliptical - 100,000 year cycle
• precession: changes in the tilt of the earth's axis - 23,000 year cycle
• obliquity: changes in the wobble of the earth's axis - 14,000 year cycle
• ozone forms naturally in the stratosphere
• ozone forms in the troposphere due to chemical reactions with other gases
• acid precipitation: precipitation that combines with pollutants that turn the precipitation acidic
• main sources of acid precipitation: sulphur oxides, nitrogen oxides
• effects of acid precipitation: slowed tree growth, reduces fish population, erodes materials
• positive feedback: a process in a system that encourages the continuation of the original process
• climate models: solving a series of mathematical equations that includes greeenhouse gases, solar radiation and other climatological components
• climate change impact on humans: food production, tourism and human health
• impacts of climate change on biodiversity: bleaching of corals, loss of flora and fauna, extinction risk for polar bears
• relationship between humans and environment: humans are simply one component of the natural world, humans live separately from nature
• relationship with nature dictated our actions: living in harmony with nature, or exploiting nature for economic gain
• precautionary principle: when there is a risk involved to either humans or the environment, we must act even if there is still uncertainty about the risk. it is our social responsibility to protect people and the environment from harm
• issues preventing growth of wind farms: habitat disruption, appearance, noise
• implications of large hydroelectric projects: loss of land due to flooding, displaced population, leaching, destruction of habitats
• The Richter Scale was a measure of the strength of a wave 100 kms from the epicentre
• the moment magnitude scale (M) is determined by: area of rock ruptured along a fault, distance of movement along a fault, strength of rock at focus
• the modified mercalli intensity scale: qualitative scale based on damage to property and people
• earthquake processes: friction along plate exerts stress, when the stress exceeds the strength of the rocks there is sudden movement along a fault, this rupture starts at the focus and propagates as seismic waves
• fault types are distinguished by the direction of displacement of the rock
• two types of faults: strike slip and dip slip
• strike slip faults: displacement is horizontal
• dip slip faults: displacement is verticle
• best example of strike slip fault is: san andreas fault
• three types of dip slip faults: reverse fault, thrust fault, normal fault
• reverse fault: the hanging wall is moved up relative to footwall at an angle above 45 degrees
• thrust fault: the hanging wall moves up relative to the footwall but at an angle less than 45 degrees
• normal fault: the hanging wall has moved down relative to the footwall
• footwall: where miners place their feet
• hanging wall: where miners place their lanterns
• fault activity: active, potentially active, or inactive
• active: movement within the last 11,600 years
• potentially active: movement within the last 2.6 million years
• inactive: no movement during the past 2.6 million years
• tectonic creep: the extremely slow movement of rock along a fracture caused by stress
• body waves: P and S waves
• P waves: primary or compressional, move in push pull motion FAST - can travel through solids or liquids