Struggle Points:

Classification - The grouping of items based on common characteristics

Density - Amount of mass per unit of volume. Density has the units: g/cm^3 or g/mL

Mass - The amount of matter in an object. The unit for mass is grams (g).

Volume - The amount of space an object occupies. The units for volume are cubic centimeters (cm^3) and milliliters (mL). 1 cm^3 = 1mL

Density Triangle - M/D = V, M/V = D, D*V=M

Density of an object doesn’t change if it is cut. It will change if it is compressed, expanded, heated up, or cooled down.

If the volume of an object increases, the density will decrease.

Objects that are heated up expands and objected that cool down contracts.

y axis = dependent variable

x axis = independent variable

Four types of relationships in line graphs:

Direct relationship - as x increases, y increases

Indirect/inverse relationship - as x increases, y decreases

Cyclic relationship - as x increases, y increases and decreases in a predictable rate

Static (no relationship) - As x increases, y does not change

Bar graphs - Represent data that has been counted

Longitude lines - These lines increase by 15 degrees when it moves to the east or the west. When it comes to constellations, the constellations will always move counterclockwise or to the east.

International Date Line - The Line opposite of the Prime Meridian at 180 degrees longitude, which is also the starter point for time zones. When you cross the line heading west, it is a day later. If you cross the line heading east, it is a day earlier.

Minutes (when it comes to degrees) - The smaller units that degrees are divided into. A degree is divided into 60 minutes or 60’.

Polaris (North Star) - Used to determine the latitude you’re on in the Northern Hemisphere. It is found right above the North Pole.

Altitude of Polaris - The angle of Polaris above your horizon. By measuring the altitude of Polaris, we can determine the latitude we are standing on in he Northern Hemisphere. Usually the altitude of Polaris is the same as the latitude of the observer

Sextant - instrument that measures angles of celestial objects.

Celestial Objects - objects in space.

Horizon - the line where the Earth’s surface and sky appears to meet.

Locating Polaris - The 2 stars at the end of Ursa Major (Big dipper) points to Polaris which is the star at the end of the handle of Ursa Minor (Little dipper)

Foucault Pendulum - Used to prove that the Earth rotates.

Earth’s rotation - The Earth rotates 360 degrees in 24 hours which means each line of longitude measures 15 degrees and there are 24 time zones, 1 for each line of longitude. There is a 1 hour time difference for each 15 degrees change in longitude.

Difference in Time zone - East Increase, West Less.

Sea level - Always has an elevation of 0

Index contour line - A contour line that is slightly darker than the others and it has its elevation labeled on it.

Rivers/streams flow from higher elevation to lower elevation.

Depression - Topographic feature where the land dips to lower elevation. Craters or the inside of the top of a volcano are examples of depressions and usually we use hachure marks (small tick marks).

Gradient - The value for the slope of the land. High gradient represents a steep slope. A low gradient represents a gentle slope. Calculate rise/run for gradient or change in field value/distance.

Isoline - Line that connects points of equal value on a map.

Continental Drift theory - Theory that states that the continents used to be joined together but they split and moved into the position they are now. Wegener called it Pangaea.

The lithosphere - Top layer of Earth which the crust is a part of. This is made out of tectonic plates. The lithosphere follows the movement of material in the asthenosphere.

Asthenosphere - Top part of the mantle. It is unevenly heated by Earth’s core which causes the tectonic plates to move. The mantle rock is somewhat fluid since it’s partially melted which makes the asthenosphere able to transfer heat through convection.

Divergent Plate Boundary - Two oceanic plates move apart from each other, causing a mid-ocean ridge to form, filled with magma creating new crust.

Transform Plate Boundary - Two continental crusts will slide past each other, causing earthquakes to form.

Oceanic Oceanic Convergence - Two oceanic plates move towards each other, causing a ocean trench (deep depression) to form.

Using sonar and submersibles, scientists were able to gather data of rocks from the ocean floor. This revealed that the ocean floor wasn’t flat but actually made up of mid-ocean ridges and oceanic trenches.

Sea Floor Spreading - New crust or lithosphere is created at a divergent plate boundary. The new crust is hot and less dense, causing it to have a higher position than the older crust which leads to a mid-ocean ridge to form.

Rift valley - The part between the two diverging plates where new crust has been created.

Magnetic Reversal - The Magnetic North Pole and Magnetic South Pole has switched positions throughout Earth’s history. This is seen on the lithosphere where a mid-ocean ridge has formed. As it switches positions, the crust will align iron-bearing minerals in the rock based on where the magnetic North and South pole is at.

Convection - Transfer of heat from one place to another by movement of a fluid that carries thermal energy and creates a circulation motion of warm and cold fluid (Convection current).

Convection in Earth’s mantle - Heat from inside Earth’s core is transferred to the asthenosphere which causes the mantle rock to heat up. It then rises since its less dense than cooler mantle rock. The heated rock then cools down and spreads out and sinks into the lower asthenosphere.

Affect of Convection on tectonic plates - The magma rises through the asthenosphere and some of it pushes through the lithosphere (crust) at a mid-ocean ridge.

Mantle material at convergent plate boundaries - The mantle material sinks and pulls the subducting tectonic plate with it, causing the plate to eventually melt.

Planets developed layers due to the pull of gravity on materials of different densities. The more dense material would sink into the center and the less dense material would stay at the surface.

Seismic waves - shockwaves of energy released from earthquakes that change speed and direction as they pass through different layers with different compositions.

Stiffer mantle - The lower layer of the mantle composed of solid rock.

Outer core - Composed of liquid iron and nickel. Seismic waves cannot pass through liquids.

Inner core - Composed of solid iron and nickel.

Earth’s magnetic field - thought to exist because the solid iron core is surrounded by liquid hot iron metal. The flow of liquid iron metal creates electric currents which creates the magnetic field which protects the Earth from the most radiation given off by the Sun.

Inferior temperature line - Actual temperature of a layer.

Melting point line - The temperature necessary for the material in that layer to completely melt.

Fault - fracture in Earth’s crust.

Focus - The point under the surface where the earthquake starts. The epicenter is directly above this.

Seismometer - the instrument used to detect and measure seismic waves.

Body waves - P Waves move straight and flat and S Waves moves wavy.

Surface waves - Love waves move up and down continuously and Rayleigh waves moves up on a surface.

Refraction - The differences in density for each layer of Earth would cause the waves to change direction. P-waves refract when passing through a solid inner core which caused them to show up in only some areas.

S-waves don’t appear at all when passing through a liquid outer core.

Determine the Epicenter distance - Subtract S-wave arrival time minus P-wave arrival time.

Determine arrival time of P-wave and S-wave - Determine the travel time for the seismic wave using the distance provided and add it to the earthquake origin time.

Determine Origin time of the Earthquake - Determine the time difference between the seismic waves and determine the epicenter distance using the time difference. Using the epicenter distance, find the travel time for one of the waves and subtract it from the arrival time. Another way is to use the epicenter distance to find the travel time for the seismic wave provided and subtracts the seismic wave arrival time and the seismic wave travel time.

Triangulation - We use the distance information from three seismic stations to locate the epicenter of an earthquake. To do it we calculate the difference in arrival time between the seismic waves then we determine the epicenter distance. The distance will be the radius of a circle drawn around the seismic station. Draw the circle for the epicenter distance around the seismic station using a compass and map scale. Where the circles intersect represents the epicenter.

Magnitude - Strength of an earthquake. We measure it using the Richter scale. This scale measures from 1 to 9+, the higher the number, the greater the strength of an earthquake.

How to calculate the magnitude on the Richter Scale - Determine the distance to the epicenter of the earthquake. Measure the maximum wave height of the S-wave recorded on the seismogram. Place a straightedge between the distance to the epicenter and the height of the largest s-wave on the appropriate scales. Draw a line connecting the two points. The line will intersect the magnitude.

Earthquake can cause a landslide and a tsunami to form. Earthquakes with an epicenter in the ocean can trigger a tsunami. The shaking during an earthquake can loosen the ground on a hill and gravity will cause it to rush down the hill.

Isoseismal lines - Identify areas of equal intensity

Matter - Anything that takes up space and has mass. They’re also made up of atoms made from protons, neutrons, and electrons.

Element - A substance (an atom) that can’t be broken down into smaller, stable parts by physical or chemical means.

Physical properties - Can be observed without changing the composition of a substance. (Ex - color, hardness, and density)

Chemical properties - Can be observed when a substance reacts with other substance. (Ex - iron reacts with oxygen to form rust)

Mineral - Naturally occurring, pure chemical substance

Physical and Chemical Properties of minerals - Color, Streak, Luster, Hardness, Dominant form of breakage. This is determined by the internal arrangement of the atoms that make up its chemical composition.

Luster - The way light is reflected off the surface of a mineral.

Hardness - a mineral’s resistance to being scratched

Cleavage - when a mineral breaks smoothly (in a box shape or flat sides)

Fracture (opposite of cleavage) - When a mineral breaks without any shapes forming. There is no pattern to how it breaks.

Streak - The color of the powder of the mineral when scratched on a streak plate.

Ore - Naturally occurring solid material from which a metal or valuable mineral can be profitably extracted.

Minerals form in areas once covered by salt water, where magma is cooling, where rock is undergoing metamorphosis, and where crystals precipitate out of hot water solutions from groundwater.

Transpiration - The process by which liquid water is carried through plants from the roots to small pores on the leaves, where it changes to water vapor and is released to the atmosphere (Evaporation).

Aquifer - the saturated rock or sediment layer that stores water and allows it to flow as groundwater.

Watershed - an area where all the precipitation, runoff and groundwater drains to the same place.

Carbonation - Carbonic acids dissolves minerals. Carbon dioxide in the air or soil can dissolve in water and this produces a weak acid that can dissolve rock. Any rock made of the minerals with CaCO3 in their composition, are carbonate rocks.

Hydrolysis - Occurs when water reacts with the mineral in rocks. Sometimes rocks absorb water, swell, and become softer. This makes it easier to break apart. When water contains salt, salt crystals can form in rock pores causing the rock to further break apart.

Oxidation - When oxygen reacts with some minerals that contain iron, the mineral will break down and rust.

Differential weathering - the process by which the softer parts of a rock wear away faster than the harder parts because they’re less resistant.

Surface area - The total amount of surface an object has.

Soil consists of weathered rock material, decayed organic material, air, water, and living things (that live in the soil).

Horizon - Soil formation continues over a long period and gradually develops layers.

Temperature and moisture influence the speed of chemical reactions which helps control how fast rocks weather and dead organisms decompose. Soils develop faster in warm, moist climates.

Soil conservation - the management of soil to prevent its destruction and loss. Examples are strip cropping, terracing, windbreaks, contour cropping, cover crops, and no till planting.

Porosity - The total amount of open space between the particles in the soil. This is determined by the shape of the particles, tightly packed they are, and if they’re sorted in size.

Permeability - the ability of a liquid to pass through. Permeability increases as the particle size increases and the rate of permeability increases as the time it takes the water to infiltrate decreases.

Capillarity - the movement of a liquid upward against gravity. This increases when the particle size decreases.

Horizontal sorting occurs as the stream slows down and deposits sediment as the inside of the meander bends.

Graded bedding (vertical sorting) occurs when a stream enters a deep lake. The biggest densest and roundest sediments would settle at the bottom.

Streams form v-shaped valleys while glaciers form u-shaped valleys

Water and wind deposit sediments that are sorted and layered. Gravity and glaciers deposit sediments that are unsorted and unlayered.

Humid climate will lead to smooth landscape with rounded slopes while arid climate will lead to steep slopes with sharp angles as an landscape.

Plains landscape - Horizontal sedimentary rock layers at low elevations.

Plateau landscape - Horizontal sedimentary rock layers at high elevations.

Mountainous landscape - Consists of folded, faulted, tilted igneous and metamorphic rock layers at very high elevations.

The Catskills is a plateau.

Relative age - The age of a rock layer based on its position compared to other rock layers.

Principle of Original Horizontality - Sediments are deposited in horizontal layers parallel to the earth’s surface.

Law of superposition - The oldest layer is on the bottom and the youngest is at the top.

Law of Intrusive Relationships - Intrusions are always younger that the rock layers that it goes through/intrudes.

Law of cross cutting relationships - A fault is younger than the rocks it cuts through.

Folds and tilts - All deformations are younger than the rocks that are deformed.

Inclusions - All fragments in a rock are older than the rock in which they appear in.

Unconformity - A buried erosional surface. This means that uplift, weathering and erosion, and subsidence has occurred.

Volcanic Time Markers - Layers of ash that had been buried under more rock layers that can also be used to find out the absolute age.

The Sun’s energy is absorbed by the earth’s surface and reradiated out as infrared energy.

Greenhouse gases - Carbon dioxide (CO2), Water vapor (H2O), Nitrous oxide (N2O), and Methane (NH4) absorb infrared radiation in the atmosphere.

Good absorbers of radiation are good radiators.

As the temperature and/or moisture increases, air pressure decreases.

Air pressure decreases with altitude. The higher the altitude, the more colder the temperature is which means the air pressure would be low.

Hottest part of the year is the end of July and the hottest part of the day is after 1:00PM.

Wind - The movement of air. It formed due to differences in air pressure. High pressure areas would move to low pressure areas with wind.

High Pressure System - They are cool and dry and the wind blows clockwise out from the center.

Low Pressure System - They are warm and wet and the wind blows counterclockwise towards the center.

Weather moves from west to east in the U.S. due to the prevailing winds between 30 degrees North and 60 degrees South blowing from the south west.

Fronts form when air masses meet.

Cold fronts move the fastest.

Stationary Front – a front that does not move or barely moves, behaves like a warm front.

Triangles represent cold while semicircles represent warm.

The direction of the shape is where the air mass is moving to. If the cold air mass is moving south, the triangles will be on the south side of the front, pointing southward.

Sling psychrometer - Measures the dewpoint temperature and relative humidity

Anemometer - Measures windspeed.

Wind vane - Measures wind direction.

Barometer - Measures atmospheric pressure (barometric pressure).

Rain gauge - Measures the precipitation rate.