Review of the Earth Science Curriculum

FROM McGUIREEquations*Density= mass/volumeunits: g/mL = g/cm3 Density of water= 1g/ml=1g/cm3*Diameter of Earth = 8000 miles -> nearly spherical (oblate spheroid)*Earth rotates at 15 degrees/hour*Gradient = change in field value/distance = Difference in elevation between A&B /distance between A&B (m/km)*23.5 degrees = Capricorn (south) and Cancer (north)*Deviation (%)= (Difference from accepted value/accepted value) x 100*Eccentricity= distance between foci/length of major axis e=d/l …. No units!

Information to Remember*Graphs: x-axis is independent variable (time, distance) and y-axis is dependent variable (Temp., height, population)*Earth bulges due to rotation-> about 40 km at the equator (oblate spheroid)*The farther an object is from Earth’s center, the less it weighs (weighs more at poles than equator)*Diameter at poles = 12,714 km Circumference at Poles = 40,076 km*Diameter at equator = 12,756 km Circumference at equator = 40,076 km*Structure of Earth: Lithosphere (solid), hydrosphere (liquid) and atmosphere (gas)*Layers of Atmosphere: troposphere (12 km), stratosphere, mesosphere and thermosphere*Pressure decreases as you go up into the atmosphere*Latitude north of equator is almost equal to the angle of Polaris (North Star)*Two Stars at the end of the bowl of Big Dipper point to Polaris*End of handle of Little Dipper is North Star/Polaris*Magnetic field is within about 12 degrees of Earth’s axis*Topo maps: V’s point upstream

Astronomy*Celestial objects tend to rise in an easterly direction and set in a westerly direction*Celestial objects tend to move along a curved path*Moon revolves around Earth in about 27 days and as a result, the moon rises about 50 minutes later each evening*The moon’s path through the sky is higher or lower, depending on the season*Each planet has its own characteristic motion-> wandering motion*Earth spins counterclockwise on its axis*Earth takes 365.5 days to revolve around the sun; approximately 1 degree/day*At the poles, the Foucault Pendulum appears to rotate in a complete circle in 24 hours*Period of rotation increases when pendulum is located at lower latitudes*At the equator, the pendulum does not appear to rotate at all*Coriolis effect is the result of inertia acting on a rotating planet

*Autumnal equinox: sun rises due east and sets due west- sunlight lasts for 12 hours -> can last longer but doesn’t due to refraction*Sun is higher in the summer than in the winter in NY, but never overhead- can only be overhead between 23.5 degrees south and 23.5 degrees north latitude*Seasons are caused by a combination of the 23.5 degree tilt of the axis and Earth’s revolution around the sun*12 hours of daylight at the equator throughout the year*In NY: 9 hours of daylight, 15 hours of darkness -> winter solstice… opposite for summer solstice*Earth is 95 million miles from the sun when farthest, 91 million miles when closest*Moon phases are due to the changing relative positions of Earth, the sun and the moon*Moon revolves around the Earth in 27 days, but it takes 29.5 days to complete a cycle of phases- this is because the Earth orbits the sun- the moon must move 30 degrees to compensate for Earth’s orbital motion around the sun*The moon rotates and revolves like other celestial objects*The moon’s period of rotation and revolution are equal, so the same side of the moon always faces Earth*Half of the moon is always lit*Moon’s orbit is tilted at an angle of about 5 degrees with respect to Earth’s orbit*Seasonal variations in temperatures result from parallelism, the tilt of Earth’s axis and Earth’s shape*In most places, the difference between high tide and low tide is less than 1 meter*The cause of the tides is the gravitational attraction of the moon and the sun*The highest high tides and the lowest low tides, called spring tides, occur about twice a month near the full and new moon phases, when both the sun and moon pull in the same line*When the sun and moon are at right angles at the first and last quarter phases of the moon, the changes in water level are more modest- these are called neap tides*Moon has bigger effect than sun because it’s so much closer to Earth*The orbits of all planets are ellipses with the sun at one focus*The paths of many comets are long and narrow*The orbits of the sun’s planets are very close to circular, with the two foci close together*The force of gravity depends on the mass of each object and the distance between them. Increase mass, increase force of gravity. Increase distance, decrease the force of gravity*Weight changes, mass stays the same*The object a satellite orbits is called the primary*Planets move fastest in their orbit when they are closest to the sun and the slowest when they are farthest from the sun*The elliptical path of any satellite is the result of inertia and gravity*Gravity causes the direction to change continuously as the satellite moves in a circle; gravity causes speed to change also*Orbital velocity of a planet depends only on its distance from the sun*Solar system is about 4.6 billion years old, which is only about 1/3 the age of the universe*We are all made of “star-stuff”- explosive deaths of giant stars produced heavy elements such as carbon, iron, silicon and oxygen

*Rock planets: Mercury, Venus, Earth, Mars, and Pluto*Gas Giants/Jovian Planets: Jupiter, Saturn, Uranus and Neptune- mostly compressed gases surrounding a tiny liquid and/or solid core*Pluto is no longer considered to be a planet. It is thought that Pluto originated as a moon and escaped from another planet*Venus is a little warmer than Mercury because Venus has dense atmosphere of CO2.*Pluto is 40 times farther from the sun than Earth*Mars has a thin atmosphere of mostly CO2, so greenhouse effect isn’t as great*Jupiter’s moons have abundant water in the form of ice and Mars has evidence of past erosion by water*Earth has liquid water and an abundance of free oxygen -> both needed to support life*An asteroid can have an orbit that crosses Earth’s orbit. There is evidence of an asteroid that hit 65 m.y.a. Some believe that this asteroid sent tons of dust into the atmosphere, cooling Earth dramatically and blocking out the sun.*Meteor impacts were more common early in the history of the solar system- most of the debris has been swept up by planets*Heating of the sun causes comets to partially vaporize, producing a tail*Halley’s Comet has a period of 75 years, and it should be coming back around in 2061*The sun is an average star*Hertzsprung-Russell diagram (h-r diagram) groups stars by color (indication of temp) and luminosity. Most stars can be classified as dwarfs, main sequence (like our sun), giants and supergiants*Very large stars move beyond the main sequence relatively quickly then become unstable and explode as supernovas*”Life Cycle” of a star: gas cloud (nebula)->proto-star->red giant->explosion -> white dwarf ->black dwarf*The sun gets energy from nuclear fusion*The sun rotates on its axis every 27 days*Sun spots come and go in cycles of about 11 years*The Milky Way is a spiral galaxy*The Earth, sun, and other nearby stars move in an orbit around the center of the Milky Way galaxy- 1 revolution takes about 220 million years*The Andromeda galaxy is our twin neighbor*Galaxies are clustered in large groups with large, relatively empty spaces between them – super clusters*Evolution of Galaxies: Barred spirals -> elliptical galaxies -> spiral galaxies*Dark lines (missing wavelengths) replace colors absorbed by elements. Each element in the stars adds its own unique signature of dark lines.*The more distant the galaxy, the greater the red shift- this shows that the universe is expanding*Red = long wavelengths Blue/Violet=Short wavelengths*Age of the universe (Based on Hubble space telescope and other instruments) = 13.7 billion years*Light takes about 1.5 seconds to get to the moon and 8 minutes to get from the sun to Earth*Light from the nearest star takes about 4 years to reach us

*The universe is thought to be about 25 billion light-years in diameter*The ultimate fate of the universe depends on the balance between the rate of expansion and the escape velocity- This is determined by the mass and density of the universe*Possible fate of the universe: Accelerating expansion, continuous expansion, balance or collapse. *Gravity is thought to hold the universe together

Geology*Rocks are made up of minerals*Fossil fuels are found in naturally occurring underground deposits and form from the remains of living things.*Some minerals are chemical elements whereas others are compounds or are mixtures*Minerals made up of mixtures do not have exact chemical formulas*Graphite and Diamond are different forms of elemental carbon*Feldspar contains potassium, calcium, and/or sodium in varying proportions along with Si, O2, and Al*Clay, feldspar, quartz and calcite make up the bulk of rocks found near Earth’s surface*Pyroxene, amphibole and olivine are common deep underground*Pyrite = fool’s gold*White or colorless minerals often have impurities that change the color. Impurities are less visible with darker minerals*Metallic: shiny, polished metal look, caused by almost all of the light being reflected*Quartz: hexagonal crystals Calcite: Rhombohedral crystals (rectangular) Halite and Pyrite: cubic*Mica crystals grow in thin, flexible sheets*The Mohs’ scale is a relative scale that measures hardness. Talc is the softest mineral with a hardness of 1 and the diamond is the hardest natural substance. A fingernail is around 2.5, a penny around 3.5, an iron nail around 4.5, window glass around 5.5, steel file is 6.5 and a porcelain streak place is around 7.*Quartz breaks along curved surfaces, a property known as conchoidal fracture.*Gold is the densest substance we commonly see, at about 19 g/cm3*Density can be measured by dividing the mass by volume, or by floatation.*A substance will sink in a liquid that is less dense than it is and float in a liquid that is denser than it is*A clear calcite crystal will show a printed line or word double when it is viewed through the sample. Calcite also bubbles when acid it dropped on it*Uranium is radioactive, which can be detected with a G-M counter.*Some samples of magnetite are so magnetic they will pick up paper clips or small nails.*Rocks are classified according to their origin*When magma cools to about 600 to 1000 degrees Celsius, it crystallizes, or becomes a solid.*At the temperature of solidification, molecules arrange themselves into an ordered pattern and form crystals.*Slow cooling allows molecules enough time to form large crystals, such as granite and gabbro*In general, igneous rocks that cool slowly deep within the Earth, where temperatures are just below the melting temperature, are composed of large crystals.*A lack of layering is a characteristic of igneous rocks, however, successive lava flows can form a layered igneous rock structure.

*The most common igneous rocks are classified using crystal size and color.*Most sedimentary rocks are composed primarily of weathered remains of other rocks.*Sedimentary rocks usually form by the compression and cementing of sediment particles or grains.*Sedimentary rocks are common at the surface, while igneous and metamorphic rocks are more abundant within Earth*Shale is made of tiny clay particles that are not visible to the unaided eye.*Siltstone is composed of particles between the size of sand and clay.*Unlike igneous rocks, metamorphic rocks never quite melt*Metamorphic rocks are the only rocks that form directly from another rock*The process of metamorphism may cause structures to become distorted or to disappear. It may cause new minerals to form and/or crystal to grow.*Most metamorphic rocks are formed deep (up to 20 km) within Earth. These rocks are pushed to the surface when mountains form and erosion takes place.*Because contact metamorphism does not involve high temperatures and pressures found deep inside Earth, the rocks are usually not changed as much as they would in regional metamorphism*When siltstone comes in contact with a molten igneous rock, the sand and clay is baked, forming hornfels*Changes from one rock one rock type to another may require thousands or even millions of years*Although conglomerate is a sedimentary rock, some of the rock fragments within it may not be sedimentary.*The fossil fuels (coal, oil and natural gas) were formed millions of years ago from the remains of ancient organisms. Fossil fuels are nonrenewable resource*Coal is the most abundant fossil fuel, it is estimated that worldwide coal reserves will only last 200 years*Most of the world’s petroleum is in the countries of the Persian Gulf. The U.S> only has about 2% of oil reserves or 22 trillion estimated barrels.*Petroleum is also used to make plastics, synthetic fabrics, medicines, insecticides, fertilizers and detergents.*When the stress on the crust is greater than it can resist, the crust shifts and breaks, suddenly releasing energy.*The Mercalli scale is a scale that measures the intensity of an earthquake, and is based on observations of those who experienced the earthquake or the damage.*Structures built on solid bedrock are more likely to survive an earthquake, and structures built on sediments and landfill are more likely to have intensified shaking.*The Richter scale records the magnitude of an earthquake.*Magnitude scales are logarithmic. Each increase of one unit means a 10-fold increase in shaking.*P-Waves travel the fastest.*A third category of seismic waves is the surface waves. These waves include both push-pull and side-to-side motion. Surface waves cause the most damage as they travel along the Earth’s surface.*As seismic waves travel outward from the focus, the time delay between the P-waves and S-waves increases.

*Finding epicenter: subtract P-wave arrival time from S-wave arrival time, make two marks on the edge of a paper, line the marks up with the p- and s-curves on the reference tables, and then follow the edge straight down to the horizontal axis to find the distance to the epicenter. Use a compass to draw a circle around the reporting station for the distance found using the p- and s- wave arrival times. Repeat twice to find the epicenter.*To find the origin time, you need to know the arrival time of the p-waves. You also need to know the amount of time that the p-waves took to get there. To determine the origin time subtract the travel time from the arrival time.*In most places, a thin layer of sedimentary rocks covers the granite-like (granitic) rocks of the continental crust. The deep continental crust as well as the oceanic crust, which is under the layers of the marine sediments, is composed mostly of darker and denser mafic rocks similar to basalt (basaltic).*As earthquake waves travel toward Earth’s center, they reach a layer in which their speed suddenly increases: the Moho (or the Mohorovicic) discontinuity is the layer between the crust and the mantle.*Scientists have calculated the average density of Earth to be about 5.5 times the density of water. That is about twice the density of most rocks found at Earth’s surface.*The composition of magmas from deep within Earth includes a high proportion of the dense, mafic minerals (mostly olivine and pyroxene).*A large portion of the meteorites that fall to Earth are composed of the mafic minerals. Perhaps, meteorites are the remains of the material from which Earth formed billions of years ago.*The outer and inner cores are thought to be mostly iron mixed with a smaller amount of nickel. These materials are relatively dense, so it is logical that these densest materials would have moved into Earth’s center.*The part of Earth opposite the side where the earthquake occurs receives P-waves, but no direct S-waves.*The zone where no waves are received is called the shadow zone. Refraction of the waves at the mantle-core boundary causes this ring-shaped region. It extends from an angle of 102 degrees to 143 degrees from the epicenter.*In general, the deeper rocks are more rigid, and this causes seismic waves to travel faster and bend down within Earth.*Subsidence is when land sinks, and landslides damage buildings, roads, municipal services and communications.*Earthquakes in or near the oceans may cause tsunamis or tidal waves. When tsunamis reach land, they can increase in size and cause devastation in local areas.*Fire is also a hazard in earthquakes as gas lines rupture and sparks from damaged power lines may ignite the gas.*Water pipes may be broken, which stops the flow of water, making fighting fires difficult.*Sediments saturated with groundwater can actually become like a fluid when they are shaken. This process is called liquefaction*When volcanoes erupt they often spew hot lava, ash, and/or toxic gases. Lava and ash can bury things, and toxic fumes can flow down the volcano’s slopes to suffocate living things.*Other dangers from volcanoes can result from landslides, mudflows, and floods from melted snow pack, especially from high volcanic mountains

*Volcanoes can also be helpful by providing some of the most fertile soil and geothermal energy.*Seismic events shape the land and thereby influence climate*Continental drift: Wegener proposed that the opening of the Atlantic Ocean broke apart an ancient supercontinent that he named Pangaea.*Wegener looked at ancient mountain ranges, similar continental rock formations, and evidence of ancient glaciers. There were also similar fossils on both sides of the Atlantic.*Ocean ridges: where the ocean floor is opening up or spreading out from. The age of the rock increases as you move away from the ridge.*Scientists have found stripes of rock with normal magnetic polarity alternating with stripes of rock that had reversed polarity. While the rock was still molten, the iron particles lined up with Earth’s magnetic field.*Crust is being swallowed back into the Earth at the ocean tranches.*Sea-floor spreading is the creation of the ocean floor by divergence at the ocean ridges.*The margins along which plates meet and interact are called plate boundaries. As plates move, major geologic activity, like volcanoes, earthquakes, and mountain building occurs.*A pluton is an underground chamber of magma.*Earthquake foci occur where the oceanic plate dives beneath the continent. Only in subduction zones do seismologists find foci to a maximum depth of about 700 km. This is where relatively cool and brittle (rigid) lithosphere is being drawn into the more plastic asthenosphere.*There are many shallow earthquakes (less than 70 km) at the ocean ridges where hot material rises toward the surface.*The collision of two continental plates leads to folding, faulting and mountain building (i.e. India crashing into Asia, Appalachian Mountains)*The Atlantic Ocean is widening at a rate of about 3 centimeters (1 inch) a year.*In general, the plates move away from the mid-ocean ridges and toward the trenches.*Earth’s temperature increases with depth. Since heat always flows from places of high heat to areas of low heat, heat flows from the center of the Earth toward the surface.*Heat from ongoing radioactive decay along with heat left over from Earth’s formation billions of years ago rises toward the surface in convection currents. These currents drive plate motions*Under the conditions of extreme heat and pressure found within Earth, the mantle behaves as a fluid, and it is able to flow very slowly.*The plates move because they are driven by convection within the mantle.*The rigid portion of the plates includes Earth’s crust as well as a small part of the upper mantle. This is known as the lithosphere.*The plates float on a more fluid and partially molten portion of the mantle called the asthenosphere.*When rocks are uplifted and exposed to wind, water and biological processes, their new environment changes them.*Plant roots that grow in the cracks of rocks and animals that burrow beneath the ground and expose new rock surfaces are agents of physical weathering.*The five major natural agents of abrasion are: flowing water, moving ice, waves, wind and gravity*Harder minerals, like quartz (silica) and feldspars resist physical weathering, but softer minerals, such as mica and clay are quickly broken apart by physical weathering.

*Deep within Earth’s crust, most minerals remain stable under the conditions in which they were formed. However, when these rocks are uplifted to the surface and exposed to the atmosphere and hydrosphere, they often undergo chemical weathering.*The rusting of iron is an example of chemical weathering. Iron atoms combine with oxygen atoms to form rust (iron oxide).*When feldspar is uplifted to the surface, it weathers, and the amount of feldspar and quartz in the sample decreases, being replaced by clay and iron oxide.*Quartz is relatively stable and resistant to chemical weathering, however, olivine, a mineral that is common deep within Earth, quickly weathers to clay when it is exposed to the atmosphere and hydrosphere.*Limestone is a fairly hard rock that resists physical weathering until its calcite is decomposed by exposure to acids. Rainwater absorbs carbon dioxide from the atmosphere and organic acids from soil to become slightly acidic. Atmospheric pollutants, such as the oxides of sulfur and nitrogen, can make rainwater unnaturally acidic. Calcite reacts with the acid. The product of the reaction is soluble in water and is carried away.*In cold dry areas, there is a faster rate of physical weathering. In warm and wet climates, there is a faster rate of chemical weathering.*Under natural conditions, biological, physical and chemical weathering processes are usually involved in the development of soils.*The decay of organic remains produces organic acids, which accelerate chemical weathering.*Burrowing animals, such as earthworms, insects and rodents, help air and water circulate through the soil and mix mineral and organic matter.*Soils contain mineral content, air, water, and organic matter in highly variable percentages.*The gradual formation of soil in place produces layers known as soil horizons. This is a residual soil. The top layer is usually the best for growing crops because it is rich in dark-colored organic matter called humus. The lowest layer of the soil is generally composed of broken bedrock, which may merge into solid bedrock.*Continental glaciers strip the soils from where they originally form and move them.*It may take hundred of years for a single centimeter of topsoil to form.*Mining, farming, running water and wind quickly carry away exposed soil, which leads to loss of soil.*Salt used to remove ice from roads can be washed into the soil. If the salt concentration is high enough, plants won’t grow there. Plants hold the sediments in place, so without plants, erosion can rapidly carry away the soil.*The force of gravity drives most forms of erosion.*Water can act as a lubricating agent that makes mass movement more likely. Alternate freezing and thawing also accelerates this process.*Mass movement includes slow creep, slumping, landslides and even the falling of individual rocks.*Running water is the main agent of erosion in moist areas.*Particles of low density, especially organic matter, are carried along the surface by flotation*Particles rolled along the bottom of the stream require faster stream velocities to move them.*The slope (gradient) and the amount of water flowing in the stream (discharge) control the stream’s velocity.

*Velocity is increased by an increase in the amount of water flowing in the stream.*Most erosion caused by running water takes place when streams are in flood because the amount of water and the velocity of the floodwaters are increased.*Water usually flows fastest near the center of the stream away from the stream banks and the streambed. There is even a small amount of friction with the air above the water. The fastest flow is commonly found at midstream just below the water’s surface.*At a bend in a stream, the fastest flowing water swings to the outside of the bend, causing erosion along the outer bank of the meander. The slowest moving water stays to the inside of the bend, causing deposition along the inner bank of the meander.*Wind erosion occurs mainly in areas, such as deserts and beaches, where there is little plant life to hold soil in place.*Infrequent thunderstorms that occur in most desert areas cause more erosion than wind.*As a glacier moves it carries, pushes and drags loose rock material. The glacier, with pieces of rock embedded in its ice, acts like a huge abrasion system. It smoothes, striates (scratches), and grooves bedrock. When the ice melts, unsorted rocks and boulders are left scattered around on hilltops and the sides of valleys.*A continental glacier deepens and widens valleys parallel to its movement. It grinds down hills, leaving them polished and rounded.*As a glacier moves, it scours away the rock to make a U-shaped valley.*Valleys eroded by streams are more often V-shaped with narrow valley floors.*Glacier ice may move forward less than 1 meter a day. The ice in a valley glacier moves the fastest near the center of the flowing ice.*Rocks eroded by wind develop smooth, flat surfaces, or facets, with distinct edges. These angular rocks are called ventifacts. Wind-worn rocks are often pitted where softer minerals have been scoured by the wind.*Rocks transported by a glacier are usually partially rounded by abrasion and are often scratched (striated) on some faces as a result of being dragged along the bottom of the glacier.*Agents of erosion, such as gravity, water, ice and wind, are also agents of deposition.*The rate of deposition depends on the size, shape, and density of the sediment particles and the speed of the transporting medium.* Sediments that settle at a faster rate require less settling time.*The largest, roundest, and densest particles are deposited first near the ocean’s shoreline. The smallest, flattest, and least dense particles are carried farthest out from shore.*When particles settle in calm water, the roundest, largest, and densest particles quickly settle at the bottom of a layer, while the flattest, smallest and least dense settle out later at the top of the same layer. This may occur when a landslide suddenly dumps particles of many sizes into still water.*Where a river or steam enters a lake or ocean, the water slows and drops its load of sediment, often in a fan-shaped deposit. This is called a delta because it resembles the Greek letter delta.*With sand dunes, sand is blown up the windward side of the dune and deposited along a steeper slope on the lee (downwind) side.*Layers that meet at different angles, a feature known as cross-bedding, are common in sediments deposited by wind.

*Glacial sediments can be divided into two kinds of deposits. Material deposited directly by moving ice contains a wide range of particle sizes without sorting or layering. Sediments deposited by streams of melt-water usually contain layers in which sediments are sorted by particle size. *Unlike water deposits, sediment left by melting glacial ice usually contains clay, sand, cobbles and boulders mixed together. These are unsorted deposits.*Continental ice covered most of NYS 20,000 years ago. The ice was a mile or more thick.*When ice forms under the weight of accumulating layers of snow, it will begin to flow downhill or away from its thickest accumulation. *Terminal moraines dammed the valleys that became the Finger Lakes*A glacier that is not advancing or retreating is said to be in a state of dynamic equilibrium. The ice itself continues to advance. However, the ice front stays in the same place because the rate of forward motion is equal to the rate at which the ice is melting back.*Seawater covers almost 71 percent of our planet. *The oceans are also very deep, with an average depth of about 4km (2.5 miles)*The deepest part of the Pacific Ocean could submerge the world’s tallest mountain with another mile of ocean above its peak*Ocean currents help distribute heat energy over the whole Earth.*Because of Earth’s rotation, all major ocean currents curve to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is due to the Coriolis Effect.*Although ocean waves appear to be carrying water along, surface water usually moves in little circles or ellipses as the wave passes. The waves actually carry energy. The energy is released as the waves slow and break.*The topography and composition of the landscape are determined by the climate, local bedrock, geologic structures, and human activities.*Tectonic forces within Earth push up mountains.*Mountains are especially common where converging tectonic plates collide. *In mountainous regions, stream gradients are high and the fast-moving streams quickly erode deep valleys between the mountain peaks.*Flat layers of sedimentary rock form the base of plateaus and plains.*Plateaus have more topographic relief than plains and less topographic relief than mountains.*Landscapes in moist climates are generally rounded. Plant cover protects the soil from rapid runoff and erosion and produces the rounded slopes characteristic of humid climates.*Landscapes in arid climates are characterized by sharp angles and steeper slopes. These climates produce thin soils with little humus. Physical wreathing is a dominant form of weathering*Even in the same climate, locations with different rock types or different structures can develop very different landscape features.*Durable, or competent, rocks form the higher portions of a landscape- the plateaus, mountains and escarpments (cliffs). The softer rocks and rocks that have been fractured usually lie beneath valleys and other low areas.*Drainage patterns are determined by the way small streams, or tributaries, join to form larger streams.*If two very different rock types occur in the same area, the harder rock will form the hills and ridges. Erosion of the weaker rocks will form the major valleys.

*If the bedrock is uniform or made of flat-lying layers, a branching drainage pattern forms, which is called dendritic (Ex. Appalachian Plateau near Oneonta)*Radial: A circular volcano or dome mountain. *Rectangular: Faulted, tilted, or folded strata (Ex. Finger Lakes; Central Adirondacks)*Annular: Dome with upturned layers*Deposits of till blocked the natural outlets of what are now the Finger Lakes. The Finger Lakes were originally valleys that were deepened and widened by the glaciers.*Poor drainage cause by glacial deposits and abundant winter snowfall makes the Tug Hill Plateau one of the least-inhabited and least used areas of the state.*Lowlands = Plains*An intrusion of basaltic magma (sill) cooled, solidified, and later was eroded by the Hudson River. This sill forms the high cliffs, called the Palisades, seen on the NJ side of the River.*Along the north shore and the center of Long Island are two terminal moraines left by the last great glacier that covered the state during the Pleistocene Epoch. The land south of these moraines is composed of sorted material washed out of the glaciers.*Agricultural and construction projects can increase erosion and affect landscape development.*It is estimated that humans currently move more rock and soil than do all rivers combined.*Planet Earth probably formed about 4.6 billion years ago from an accumulation of rock, dust, and gases drawn together by its own gravity.*There are occasional exceptions to the law of superposition, such as the effects of folding and faulting.*A unit of rock is always older than the processes that changed it.*An extrusion is younger than the rock below it and the rock will contain a zone of contact metamorphism where the hot lava baked the older rock.*Any rock above the intrusion will not show contact metamorphism. *With an intrusion, hot, molten rock changes the surrounding rock directly above, below and next to it by contact metamorphism. Therefore, an intrusion can be identified by the narrow zones of metamorphism that surrounds it.*Sometimes molten magma surrounds pieces of older rock. Later the magma becomes solid rock without melting the older rock fragments. These fragments of older rock (inclusions) must therefore be older than the igneous rock in which they are found.*Extreme heat from metamorphism and melting usually destroy fossils, so fossils are usually found only in sedimentary rock.*Sometimes, minerals brought in by groundwater replace the original compounds that made up the preserved body part. The remains are then said to be petrified.*Fossils that do not contain the remains of organisms are said to be trace fossils and include the impressions of shells, dinosaur footprints, oddly shaped formations resulting from sediments filling an animal’s burrow and petrified animal droppings (coprolites)*Trace fossils show more about lifestyle than what prehistoric organisms looked like.*Erosion causes gaps in the geologic record. When a rock outcrop shows an unconformity, it indicates that the area, at some time in the past, was uplifted above water level and then eroded. Later the area subsided below water level and new layers of sediment were deposited on top of the eroded surface.

*The gap in geologic record is sometimes indicated by an uneven interface or by gaps in the fossil record in the strata.*Faulting offsets layers*Scientists can match the rock strata in one location with the strata in a more distant location by comparing the properties of the rocks, such as color, texture, or composition. It is more helpful to match the sequence of rock layers, such as from limestone to sandstone then shale. However, even if the sequence of rock layers in two locations is the same, the layers may not have formed at the same time.*If layers lack a specific index fossil, they can sometimes be tentatively correlated by the kinds of fossils they contain.*A relative time scale indicates whether the object in question is older or younger than something else. Each of these groups of fossils was named for a location where its characteristic fossils could be readily observed in the rocks. For example, fossils characteristic of Devon, in the south of England, were named Devonian.*The time scale is divided into eras, which are divided into periods that are further divided into epochs.*Paleozoic = “ancient animals”, Mesozoic= “middle animals”, and Cenozoic= “recent animals”*The Precambrian was the dawn of life. For the most part, organisms had no hard parts that were easily fossilized.*The Cenozoic Era is sometimes called the Age of Mammals, which we are living at the end of.*Theory of Organic Evolution by Charles Darwin says that individuals that have traits that better adapt them to their environment will survive longer and have more offspring. By natural selection, the number of those who do not have the desirable traits will decrease. This eventually leads to the extinction of some species and the gradual formation of new species.*Some link mass extinctions to asteroid, comet or meteoroid impact events. A prime example is a recently investigated and largely buried crater in southern Mexico. This crater may have been caused by the impact of a massive object from outer space at the end of the Mesozoic Era. Global climatic change resulting from debris thrown into the atmosphere by the impact, preventing sunlight from reaching Earth’s surface and disrupting the whole food chain, is most likely the cause.*When life first developed on Earth about 4 billion years ago, the atmosphere probably consisted of a mixture of carbon monoxide, carbon dioxide, hydrogen, nitrogen, ammonia, and methane. Today, the mixture of gases in the air is very different: 78% nitrogen and 21% oxygen. Scientists now understand that organisms that developed photosynthesis more than 3 billion years ago caused this dramatic change.*Over time, the oxygen built up in the atmosphere to the point that the earliest, anaerobic (do not need oxygen to survive) organisms could not survive.*Carbon-12 has 6 protons and 6 neutrons in its nucleus, and carbon-14 has 6 protons and 8 neutrons in its nucleus.*If the nucleus of an isotope has more or fewer than the number of neutrons in its most stable form, the isotope may be radioactive.*Carbon-14, with two extra neutrons in its nucleus, is unstable. Carbon-14 will change into its stable decay product, nitrogen-14

*Since atoms decay at random, scientists cannot predict when a particular atom will decay. However, even a small sample of a radioactive element contains millions of atoms, from which scientists can predict a rate of decay.*At the end of one half-life, a sample contains equal amounts of the radioactive element and its decay product. In each succeeding half-life, half of the remaining atoms decay.*The half life of carbon-14 is 5.7 x 103 years.*The half-life for any element is not affected by environmental conditions, such as temperature, pressure, or chemical combinations.*A sample containing the remains of living organisms is likely to contain radioactive carbon-14.*Carbon-14 can only go back to organisms younger than about 50,000 years.*Uranium-238 with a half-life of 4.5 x 109 can measure samples of the oldest rocks on our planet. For very recent samples of rocks, however, too little uranium-238 would have decayed to lead-206 to make the decay product measurable.*Potassium-40 and Rubidium-87 are other radioactive decay elements… rubidium having the longest half-life and potassium being between carbon and uranium.

Environmental Awareness*Earth’s distance from the sun is just right to sustain temperatures that favor higher life-forms.*Only Earth has an atmosphere that is dense enough to protect us from harmful radiation and yet allows solar energy to penetrate to its solid surface.*Earth alone has the right mix of gases to support higher forms of life.*Organic pollution is common around cities that have inadequate ways to dispose of human and industrial wastes. It also occurs in farming areas where animal wastes and fertilizers are left on the land.*CFCs (chlorofluorocarbons) made air conditioning more affordable, but satellite-based instruments showed that CFCs were drifting into the upper atmosphere where they were destroying Earth’s protective ozone layer. CFCs convert ozone into oxygen, which does not protect us from ultraviolet radiation. *Polychlorinated biphenyls (PCBs) disperse waste heat and do not evaporate easily. They were used with transformers. The waste was dumped into the Hudson River, causing major pollution issues and the PCBs are now in the food chain (i.e. fish). *PCBs in high concentration can cause birth defects, cancer, liver damage and nerve disorders.*Photochemical smog is a big concern in LA. The mountains and the Pacific Ocean traps the pollutants by reducing the free flow of winds from the ocean. One component of photochemical smog is ozone, which is a concern for those with respiratory problems.*When fossil fuels are burned without proper pollution controls, oxides of nitrogen and sulfur are released into the atmosphere.*When nitrous and sulfuric oxides mix with water, they form acids.*Acid precipitation is a special problem in locations such as New York’s Adirondack Mountains where the bedrock has little calcite (limestone or marble), which can help neutralize acid in surface water.*The Colorado River picks up salts from the soil as it travels through the desert area in the Southwest. By the time the river reaches Mexico, very little water is left and that water is seriously contaminated with salts and other residue washed from the irrigated fields upstream.

*Pollution also includes noise, heat and nuclear (ionizing) radiation*Exposure to loud sounds can cause hearing loss.*Power plants (nuclear and fossil fuel) produce large amounts of excess heat. They use cooling towers that pump water from a nearby river to dispose of the heat. The heated water is discharged into the water, changing its ecology.*Excess heat sent into the atmosphere may cause changes to the climate, such as the formation of a heat island around a city.*Radioactive emissions given off by nuclear power plants, hospitals, and some industries can cause cancer, birth defects, and even death.*Radioactive radon gas from the decay of uranium in bedrock can seep into homes built over natural uranium deposits.*Advances in medicine and food technology caused an explosion of the human population. There are now about 6.5 billion people on Earth. It is now predicted that the population of the planet will stabilize at a sustainable number in the range of 10-15 billion.*Soil is a critical and nonrenewable resource. As more land is cleared for agriculture, more soil is exposed to erosion.*Many resources are not clearly renewable or nonrenewable, such as groundwater. It is renewable in some places but not others (like deserts)*Is fresh air a renewable resource? Could humans pollute it so badly that fresh air would no longer be available?*Throughout history, as one source of energy has been depleted, another has been developed to take its place. Solar technology, which is nearly pollution free, may provide a large part of our energy in years to come.*Our goal should be to use resources wisely and with the greatest possible awareness of our future needs.*First, scientists need to conduct scientific investigations to find the best ways to use and conserve resources. Second, scientists must explore alternative ways to provide for future needs. Third, we need to educate ourselves and our decision-makers about the need for conservation planning and scientific research.*”We do not inherit the Earth from our ancestors; we borrow it from our children”

Vocabulary*Oblate spheroid: Slightly flattened at poles, bulge at equator*Density: density of an object will always be the same, regardless of how much you have of it*Lithosphere: Solid portion of Earth, approximately 100 km thick, mostly made of oxygen and silicon*Hydrosphere: liquid portion of Earth, approximately 3-5 km thick, 70 percent of Earth, mostly made of oxygen and hydrogen*Atmosphere: gaseous portion of Earth, mostly made of nitrogen and oxygen*Troposphere: 12 km, most dense, water vapor -> clouds, temperature decreases with height*Stratosphere: ozone layer is part of this one*Latitude: North (+) and South (-). Equator is o degrees. AKA parallels*Longitude: West (-) and East (+). Prime meridian is equal to zero.

*Navigation: Science of identifying your position on Earth*Noon: When the sun reaches the highest point in the sky*Scale: Ratio of the dimensions of the real object to its model*Field: Region of space in which a similar quantity can be measured at every point or location*Isotherm: Connect points of equal temperature*Isobar: Points of equal air pressure*Contour lines: connect points of equal elevation*Topographic (contour) map: Shows the shape of the Earth’s surface*Contour interval: The difference in height between 2 adjacent contour lines*Escarpments: Cliffs*Index contour: bolded, labeled contour line*Topographic profile: cross-sectional view that shows elevation*Relief: local difference between highest and lowest elevations

Astronomy*Zenith: The point on a celestial sphere that is directly above the observer*Celestial sphere: Imaginary sphere encircling Earth on which all objects in the night sky appear*Celestial object: Object in the sky outside Earth’s atmosphere; sun, moon, stars and planets*Terrestrial: Refers to objects that are a part of Earth; i.e. rocks, clouds and oceans*Planet = wanderer*Constellations: Observed pattern people use to mark the position of stars in the sky; one of the 88 regions of the night sky each associated with a particular constellation*Geocentric (Earth centered) Model: Early model of the solar system and universe in which the Earth is stationary, located at the center of the universe and around which all celestial objects revolve*Heliocentric Model: Modern model of solar system and universe in which the planets revolve around the sun and Earth undergoes daily rotation*Phases: apparent change in shape of the lighted portion of a celestial object*Umbra: The inner and darker part of a shadow*Penumbra: The outer and less dark part of a shadow*Lunar eclipse: Occurs when the full moon moves into Earth’s shadow*Solar eclipse: occurs when the new moon briefly moves between Earth and the sun*Angular diameter: The angle formed between the sides of an object and your eye- depends on the size of the object and how far away the object is-> the closer the bigger*Ellipse: Closed curve around two fixed points known as the foci*Major axis: Line through the widest part of an ellipse*Gravity: Force of attraction between objects*Satellite: Object that moves elliptically around another object (Earth is a satellite of the sun. The moon is a satellite of Earth)*Inertia: The tendency of an object to remain at rest, or if it is moving, to move at constant speed in an unchanging direction*Big Bang: Theory that the universe began as the rapid expansion of an infinitesimal object of incredible mass and density

*Asteroids: One of the tens of thousands of rocky objects mostly located in a belt between the orbits of Mars and Jupiter. Most hit Earth’s atmosphere and burn producing streaks of visible light at night- “shooting stars”*Meteorite: Natural object that has fallen to Earth from space*Meteoroid: Potential meteors in space*Comet: Icy celestial objects, most of which originate in a region beyond the planets’ some travel in highly elliptical orbits*Star: A large, self-luminous body in space that creates its own radiant energy*Luminosity: How much light an object gives off*Nuclear fusion: Under conditions of extreme heat and pressure in the sun, the nuclei of 2 hydrogen atoms join to form 1 helium nucleus, which creates a huge amount of energy*Nuclear fission: Large nuclei from elements such as uranium are split to form smaller nuclei- does not create as much energy as fusion and creates dangerous waste products*Sun spots: Temporary storm on the visible surface of the sun- they are a little cooler and dimmer than the normal surface of the sun and they often occur in pairs with opposite magnetic polarity*Galaxy: A huge body of stars and other matter in space*Spectroscope: an instrument that separates light into its component colors*Red shift: Displacement of spectral lines of distant stars toward the red end of the spectrum; Doppler shift*Light year: Distance light travels in one year which is about 10 trillion km*Escape velocity: The speed an object needs to overcome Earth’s gravitational pull

Geology*Fossil fuels: Coal, oil and natural gas- naturally forming but not minerals because lack crystalline structure*Minerals: Natural, homogeneous crystalline inorganic substances of which rock is made*Inorganic: A substance that was not formed by or from living things such as plants or animals*Luster: Way the surface of a mineral reflects light*Crystal: regularly shaped solid formed by an ordered pattern of atoms*Cleavage: Comes from a Latin word meaning to cut; The way that a mineral splits between layers of atoms that are joined by weak bonds*Cleavage planes: Flat surfaces along which some minerals break naturally*Fracture: Uneven splitting of a mineral sample*Specific gravity: a ratio of the density of a substance to the density of water.*Igneous rocks: form when molten rock, known as magma (or lava, when it reaches the surface), cools and solidifies.*Sedimentary rocks: Typically form as a result from the compaction and cementing of layers of sediment.*Metamorphic rocks: Form when igneous, sedimentary or other metamorphic rocks are changed by heat and/or pressure.*Texture: The result of the size and arrangement of particles in a rock

*Plutonic (intrusive) rocks: Usually composed of large, readily visible mineral crystals. Pegmatite is an igneous rock with exceptionally large crystals that does not follow this rule. The large crystals in pegmatite are thought to be due to the abundance of water in the magma, and not just because of slow cooling.*Extrusive rocks: Fine-grained igneous rocks that cool quickly at or near Earth’s surface.*Felsic: Light-colored rocks compose mostly of feldspar and silica*Mafic: Composed of dark minerals rich in iron and magnesium*Vesicular: Contain many holes created by expanding gas as the magma rose to Earth’s surface. Examples: scoria and pumice*Fragmental (clastic) rocks: Most common group of sedimentary rocks, made up of different sized particles*Organic or Bioclastic: Sedimentary rock, such as coal and some types of limestone, formed by the accumulation of plant and animal remains*Fossils: The remains of prehistoric life; almost always found in sedimentary rocks.*Crystalline sedimentary rocks: Deposited by chemical precipitation of materials from solution in seawater. This occurs during the evaporation of seawater and when chemical reactions in the water form insoluble compounds that settle. Rock salt is the most common. Another example is gypsum*Foliation: Alignment or segregation of minerals in a metamorphic rock, producing a layered appearance*Banding: Type of foliation found in some metamorphic rocks that is caused by the movement or growth of minerals into homogenous layers*Regional metamorphism: The process by which rocks are transformed by pressure and heat deep within Earth*Contact metamorphism: Rocks that are altered at or near Earth’s surface as the result of nearby magma or lava*Parent rock: original rock*Natural resources: Substances that come from Earth*Renewable resources: Can be replaced after being used (Ex. trees, freshwater)*Non-renewable resources: After they are used, cannot be replenished for millions of years if at all.*Earthquake: Natural vibrations, sometimes destructive, that radiate from a sudden movement along a fault zone within Earth or from sudden movements of magma (molten rock) under a volcano.*Faults: break in the rock of the Earth’s crust along which there has been displacement (movement)*Focus: An earthquake’s point of origin within Earth*Epicenter: Location along the Earth’s surface that is directly above the focus of an earthquake.*Seismometers: Instrument that detects vibrations of the ground*Seismologist: Scientist who studies earthquakes*Seismograph: Instrument designed to measure and record the magnitude of an earthquake.*P-Wave: Compression (longitudinal) wave that is the fastest of the seismic waves that radiate from an earthquake (P-waves can travel through solids and liquids; also known as primary waves)*S-Wave: Transverse earthquake waves that arrive after the P-waves and that cannot travel through a liquid such as the Earth’s outer core; secondary or shear waves (up, down, side to side)*Origin time: Time an earthquake occurs at its epicenter

*Crust: The outermost layer of our planet, varying in thickness from about 5 kilometers under the oceans to about 60 km under the largest mountain ranges on the continents.*Mantle: Extends to a depth of about 2900 km, so it includes most of Earth’s volume.*Outer core: Outside portion of Earth’s core thought to consists mostly of liquid iron and nickel because S-waves cannot pass through it*Inner core: Central portion of Earth’s core thought to be composed mostly of solid iron and nickel*Ring of Fire: Zone of volcanoes, earthquakes, and mountain building that surrounds the Pacific Ocean.*Mid-ocean ridges: System of submerged mountain ranges that encircles Earth and often connects with mountain ranges on the continental; new crust forms here*Plate tectonics: Unified theory of crustal motion that incorporates continental drift and seafloor spreading; theory that Earth’s surface is composed of about a dozen large, rigid plates that diverge and converge, carrying the continents*Convergent boundary/Subduction zone: Region in which Earth’s crust is destroyed as it is pulled down into the mantle*Trenches: Ocean floor depression that marks the zone where crust is subducted. These are the deepest parts of the oceans.*Island arcs: Islands formed by rising magma plumes at a convergent boundary*Transform boundary: Plate boundary at which crustal plates slide past each other (ex. San Andreas Fault in CA)*Divergent boundary/Rift zone/Ridge: Plate boundary at which the plates move apart; an upwelling of material that forms new crust that moves away from the boundary*Rift zone: Linear feature of Earth where new crust is being created.*Radiation: Emission and transfer of energy by means of electromagnetic waves, and the only way that energy can travel through empty space. Radiation can only flow through the vacuum of space and through transparent materials such as air and glass*Conduction: The way heat energy is transferred through matter by the direct contact of molecules (solids; slow process)*Convection: Circulation of a heated fluid (a liquid or a gas) caused by density currents; a form of heat flow in which the heated material moves*Convection cells: Circular path of convection flow*Hot spot: Location at which a stationary hot plume of magma breaks through the crust*Weathering: The breakdown of rock due to physical or chemical changes*Physical weathering: Changes the size and/or shape of a rock without changing the rock’s chemical composition*Frost action: Important agent of physical weathering in climates that undergo seasonal temperature changes alternately above and below 0 degrees Celsius. Water seeps into cracks in rocks and as the volume of water increases as it freezes, the force makes the cracks in the rock a little larger each time the water freezes.*Abrasion: Collisions that wear down rock particles. For example, abrasion takes place when a stream that carries rock particles and they bump and rub against one another and the streambed.*Chemical weathering: Changes the mineral composition of rock, thereby forming new substances.*Soil: The mixture of weathered rock, microorganisms, and organic remains that usually covers bedrock.

*Sediments: Rocks that have been broken down into fragments, regardless of the size of the fragments*Erosion: The transportation of sediments most often by water, wind, or glaciers.*Talus: Broken rock from a cliff*Mass movement/Mass wasting: The downhill movement of rock or sediment without being carried by water, wind or ice. Material can slide, flow, or fall to its resting place.*Glacier: A large mass of slowly flowing ice.*Deposition/Sedimentation: When an agent of erosion stops transporting particles and fragments of earth materials.*Precipitates: Salt crystals that form and settle out of solution*Precipitation: Sedimentary process that involves substances settling out of a saturated solution*Horizontal sorting: Gradual change in the size, density, and shape of particles deposited when a stream slows on reaching calm water.*Glacial erractics: Large rocks that have been transported by glacial ice without being broken into small particles. They often rest high above stream valleys, which shows that they could not have been deposited by running water.*Alpine glaciers: Also known as valley glaciers, occur in mountain regions, and often carve out U-shaped valleys during their steady advance.*Continental glaciers: Also known as ice sheets, are the type of glacier responsible for most of the glacial features found throughout NYS. *Glacial polish: Bedrock surface smoothed by the passage of a glacier*Till: Unsorted glacial sediment*Drumlins: Teardrop-shaped hills. The round end of the hill faces the direction from which the glacier advanced.*Moraines: Piles of unsorted soil and rock left where the ice front stopped its southward advance*Kettles: Low spots in the glacial deposits and places where large, buried ice blocks melted leaving dry depressions.*Kettle Lakes: Lake formed when a block of glacial ice melts.*Kame: Delta deposited by a steam at the end of a glacier*Esker: A ridge made by water deposition within a tunnel under the ice*Sandbars: Ridges sometimes submerged that run parallel to the shore*Barrier Islands: A long, relatively narrow island running parallel to the mainland, built up by the action of waves and currents and serving to protect the coast from erosion by surf and tidal surges.Sand Spits: A type of bar or beach that develops where a re-entrant occurs, such as at a cove, bay, ria or river mouth. Spits are formed by the movement of sediment along a shore by a process known as longshore drift.*Landscape: A region on Earth’s surface in which various landforms, such as hills, valleys, and streams are related by common origin.*Topographic relief: The change in elevation between the highest and the lowest places.*Mountain: Has the greatest relief between the highest peaks and the deepest valleys. A great variety of rock types are common in mountain landscapes.*Plateau: Relatively flat or rolling uplands in which streams have cut deep valleys.

*Plains: Have the least topographic relief. Although there may be a few small hills, they are generally flat and at a low elevation.*Outwash plain: A relatively flat area, it is formed by layered deposits left by water from a glacier.*Uniformitarianism: “The present is the key to the past”; Principal that most geologic events of the past are similar to processes that occur in the present. For example: volcanoes, earthquakes, deposition and erosion.*Law of Superposition: Rocks at the bottom of an undisturbed exposure are usually the oldest.*Original horizontality: It is assumed that sedimentary layers that are tilted were deposited horizontally, and that the layers were tilted after they had turned into sedimentary rock.*Extrusion: Molten, liquid rock (lava) flowing out onto Earth’s surface; a fine-grained igneous rock formed by the rapid crystallization of lava at or near Earth’s surface*Intrusion: Molten, liquid rock (magma) pushed into cracks within Earth’s crust; a body of coarse-grained igneous rock formed by slow cooling within Earth.*Fossils: The preserved remains or traces of living things, tell scientists a great deal about the life forms and environments that existed in Earth’s past.*Relative age: Comparative age; age expressed as before or after other events without specifying the age in units.*Unconformity: Gap in the geologic record caused by the erosion of sediments or rock followed by new deposition. *Correlation: Matching rock layers in different locations by age or by rock types*Index fossil: Fossil found over a large geographic area but which existed for a brief period of geologic time*Orogeny: The process of mountain building.*Mass extinction: Extinction of a large number of species*Absolute time: Geologic time that uses numerical time units (years)*Isotopes: Form of an element with more or fewer neutrons in their atomic nuclei than other forms of the same element.*Decay product: Element produced by the decay of a radioactive isotope*Half-life: Time needed for half the atoms in a radioactive sample to change to the decay product.*Decay-product ratio: The ratio between the mass of a radioactive element and its decay product in a sample.

Environmental Awareness*Pollution: Any substance or form of energy in sufficient concentration to harm living things or the natural environment.*Organic pollution: Adding too many nutrients to water*Greenhouse gas: Gases, such as carbon dioxide and methane, that affects Earth’s climate