ch 9-12

  1. magma
    molten material works its way to the crust and it might not reach the surface befor it hardens.
  2. lava
    magma that reaches the ground surface
  3. viscosity
    mobility of the lava is influenced by high temp (more fluid) lower temp mobility of lava decreases
  4. more silica in the lava
    more viscous ( less fluid)
  5. disolved gases
    the gases (volatiles) which provide the forces that erupt molten rock from vent
  6. basaltic magmas
    very fluid and allows expanding gases to bubble upwards and excape from vent. Produces lava fountains
  7. highly viscous lava
    lava moves up but gases are restricted. It increases in size till they explode
  8. lava flows
    flow in thin sheets or ribbons
  9. gases
    contain disolved gases held within molten rock.
  10. composition of gases
    70% water vapor, 15% carbon dioxide 5% nitrogen 5% sulfur
  11. pyroclastic materals
    form at the surface and are are considered extrusive
  12. pyroclasts
    green, pyro, fire clastss broken fragments
  13. anatomy of a valcano
    begin with a crack onto the surface of the earth as magma moves strongly towards it
  14. conduit
    path or corridor that the magma travels through before it erupts on the surface opening called the vent
  15. crater
    deep walled depression situated at the summit of calcanoes
  16. caldera
    large more or less circular depression
  17. shield valcanoes
    • Broad gently sloping volcanoes made of solidified lava flows.
    • have grown up from deep ocean floors to form islands.
    • ex hawaiian island
  18. cinder cones
    • made of pyroclastic fragments ejected froma central vent .Slopes steeper but not as large than shield valcanoes
    • Found in flanks and calderas of hawaiian shield valcanoes
  19. composit valcanoes
    • made of alternating layer of pyroclastic materals and lava flows.
    • Slopes intermedient between shield and cinder
    • ex andes mountains
  20. ** essay Living with Valcanoes
    • supernatural belief
    • growth of an island
    • geothermal energy
    • effects on climate
    • volvanic catastrophies
  21. supernatural belief
    • In Iceland, Loki of Norse mythology is thought to have been imprisoned underground and blows
    • lavas and steams through fissures.
    • Native Americans of the Pacific Northwest
    • regarded volcanoes as warrior gods, who would throw red hot boulders.
  22. growth of an island
    Volcanoes are at times, thought to be associated with destruction, but some effects can be beneficial. Hawaii would not have existed without volcanic activity.
  23. geothermal energy
    underground heat generated can be helpful if harnessed to power turbines for electricity
  24. effects on climate
    valcanoes spewing large amounts of gas and material in atmosphere, reduses solar radiationa and drop in temperature offsetting global warming
  25. ** valcanic catastrophies
    Pompeii, Italy; Krakatoa, Western Pacific; Mt. Etna, Italy; Mt. St. Helens, U.S. of A.; Fujiama, Japan.
  26. plutons
    Structures that form from the positioning of the igneous material at depth. They can only be studied after uplifting and erosion
  27. dikes
    Tabular features that are produced when the magma is injected into fractures.
  28. sills
    Tabular features when magma is injected along sedimentary bedding surfaces.
  29. Laccolith
    similar to sills but the magma is less fluid
  30. batholith
    Largest of intrusive igneous body, when magma was formed at depth and then exposed by upliftment and/or erosion
  31. role of heat
    Heat increases with depth. Change in temperature with depth is know as the geothermal gradient.
  32. role of pressure
    increases with depth as well and is an important factor in melting the rock.
  33. role of volatiles
    • gases (volatiles) cause the rock to melt at a lower
    • temperature, similar to salt for melting ice. Their effect is magnified by increased pressure as earlier discussed
  34. Partial Melting and Magma Compositions
    • Minerals have different melting points as we studied from Bowen’s Reaction Series. As the temperature increases, the minerals with lower melting temperatures in the rock start melting and after they have melted they start rising towards the surface.
    • Slowly the composition of the magma approaches the composition of the rock from which it was formed and often the melting is not complete. This is known as partial melting
  35. deformation
    refers to all changes in the original size and or shape of the rock
  36. elastic
    rocks return to their original shape and size after the releaase of pressure
  37. plastic
    rocks do not return to their original shape and size after the release of pressure
  38. temperature
    at the surface the temperature and pressure is low
  39. brittle
    materials once the forces exceed their strength. This type of deformation
  40. ductile
    where the temperature and pressure is high at dephts, involve changing the size and shape of the rocks without fracturing
  41. rock type
    The mineral composition of the rock establishes its strength. Rocks, like basalt, granite, and quartzite that are composed of minerals break by brittle fracture, as opposed to sedimentary rocks which have zones of weakness break by ductile fracture.
  42. Time
    rocks are like a book shelf they will break and deform
  43. folds
    are formed as a result of volcanic rocks that are bent into series of wavelike undulations
  44. axial plane
    three dimensional plane which divides the limbs of the folds into more or less two equal halfs
  45. Essay 2 types of folds 3 type faults
    • anticline
    • Syncline
    • normal faults
    • reverse faults
    • slip strike fault
  46. anticline
    when the limbs of the fold dip away from the axial plane, the fold is an
  47. Syncline
    when the limbs of the fold dip towards the axial plane, the fold is a
  48. Dome
    a rough circular upfoleded structure similar to an anticline
  49. basin
    a roughly circular downfolded structure
  50. faults
    are fractures in which movement has taken place
  51. dip-slip fault
    vertical movements between the fault plane has taken place
  52. *normal faults
    is where the hanging side of the fault move down is relation to the footwall side of the fault
  53. *reverse fault
    is where the hanging wall side of the fault moves up in relation to the footwall side of the fault.
  54. *strike-slip faults
    • where horizontal movements between the fault plane has taken place.
    • two types being Right Lateral Fault and Left Lateral Fault
  55. joints
    If there is no shear displacement then the fracture in the rock is called a
  56. columnar join
    the direction of compress stress of a volcanoes
  57. sheets jointing
    expansion result of tension
  58. orogeny
    process of mountain building
  59. oros
    meanign of mountain
  60. genesis
    coming to being
  61. island arcs
    Form when two oceanic plates converge and one is subducted beneath the other
  62. mountain building along andean-type margins
    convergence of an oceanic plate and a continental plate because of subduction of the contiental plate
  63. Collisional Mountain Ranges-Continental Collisions
    • When two continental plates come together and the are separated by the ocean floor
    • the ocean floor subducts and brings the two continental plates together which then collide
    result of normal faulting where one block is thrust up and the other thrust down.
  65. Isostasy
    is defined as the balance or equilibrium of blocks floating on the upper mantle
  66. Isostatic Adjustment
    The erosion of sediments due to weathering may lower the weight of the rocks and they rebound back as the pressure is released. (like removing the weight from a pillow).
  67. geology time scale observed by
    major john wesley powell
  68. where did john wesley powell explor that earth is consealed in its rocks
    colorado river
  69. Uniformitarianism
    • present is the key to the past,
    • the processes operation on the earth today (earthquakes, volcanoes, erosion, etc.) have been operating on the earth thorough its history
  70. actualism
    he reverse of uniformitarianism, which means that the processes operating in the past are operating today.
  71. radio activity principles
    can establish the age of rocks
  72. ages of rock in the field
    based on comparison
  73. relative time
    the sequence of events that took place
  74. relative dating
    putting rocks in their proper sequence of formation
  75. numerical correlation
    the study of 2 items
  76. Essay 5 Principles Used to Determine Relative Time
    • original horizontality
    • superposition
    • lateral continuity
    • cross-cutting
    • Inclusion
    • Intrusion
  77. Original Horizontality
    that when material was initially deposited on the surface of the earth, it was deposited in a horizontal fashion. The folding-faulting observed in the rocks, was after its deposition.
  78. superposition
    • the layers below are older than the layers deposited on
    • top of them. The oldest is at the bottom and the youngest is at the top.
  79. Lateral Continuity
    the original sedimentary layer extends laterally until it tapers or thins out at the edges.
  80. Cross-Cutting
    • the disrupted pattern is older than the disruption which
    • caused it. When a fault cuts across layers of rocks the fault is younger than the layers that it cuts across.
  81. Inclusion
    • the fragments included in the host rock are older than
    • the host rock.
  82. * Intrusion
    abody of rock intrudes another one, the intruding body of rock is younger than the host rock
  83. Unconformities
    a surface that represents the gaps in geologic record.
  84. Disconformity
    Is the contact representing missing rock strata. The older rocks were eroded away which were parallel to the bedding surface.
  85. Angular Unconformity
    • a contact in which the younger strata lie over the older
    • ones that are tilted or folded.
  86. Nonconfomity
    erosion surface on a plutonic or metamorphic rock has been covered by younger sedimentary or volcanic rock.
  87. corelation
    by which rocks are similar against one another, can be within reagon a contient or between continent.
  88. physical continuity
    able to trace physically the course of a rock unit.
  89. Similarity of Rock Types
    Correlation between two rock types can be made on the assumption that the two rock types in two different regions were formed at the same time.
  90. Correlation by Fossils
    The fossils succeed one another in a predictable order.
  91. principle of faunal succession
    • If the same fossils are found between two rock types then a correlation between then can be
    • established
  92. marrie carrie
    discovered radioactivity
  93. Only after the discover of radioactivity have scientists been able to establish
    the age of rocks
  94. isotopic dating
    Establishing the age of the rock using radioactive elements is
  95. radioactive decay
    the spontaneous necular decay of certain isotopes
  96. isotopes
    Atoms of the same element having different number of neutrons but the same amount of protons.
  97. Half-life Period
    The time taken by a given amount of radioactive isotope to be reduced by one half.
  98. 100g uranium decays to
    50g uranium and 50g lead
  99. 2 radio activity of a person
    how long exposed and intense was exposure
  100. The different isotopic dating methods include
    U/Pb, Rb/Sr, K/Ar, Radiocarbon
  101. Curves Used to Establish the Age of the Rock by Comparing The Amount of Radioactive Isotope Remaining in Time to the
    orignal amount
  102. Combining relative and numerical ages gives
    better perspective regarding the occurrence of geologic events and the ages of materials
  103. numerical dating can also confirm or deny the
    observations made by relative dating.
  104. earths age of 4.5 billions years old is much older than
    the oldest rock found.
  105. earths age was made on basis of
    meteorites and lunar rocks
  106. that the planets and other bodies of the earth solar
    system, earth including formed at about the
    same time
  107. atmosphere
    thin gaseous veil which surrounds the earth and is held together by forces of gravity
  108. weather
    Is the state of the atmosphere at any given time.
  109. climate
    what the weather comditions are
    composition of the air is not constant. It varies from location to location and from time to time.
  111. Major Components of the atmosphere
    nitrogen 78% oxygen 21%
  112. atmosphere variable compoents
    include water vapor, aerosol, and ozone
  113. Atmospheric pressure
    is the weight of the air above. As the altitude increases pressure decreases.
  114. The atmosphere is divided into four layers based on
  115. thermosphere
    above the mesosphere and regions of increasing temperatures owing to the absorption of solar energy, outermost layer
  116. mesosphere
    • above the stratosphere and characterized by
    • decreasing temperatures
  117. stratosphere
    layer immediately above the troposphere and a region with high temperature owing to the concentration of ozone.
  118. troposphere
    lowermost layer and is characterized by decreasing temperatures with height.
    all of earth’s energy comes from the sun
  120. the sun is what
    The weather at any time during the year is dependent upon
  121. SSP sub solar point
    recieves direct energy from the sun
  122. rotation
    The earth rotates (or spins) on its own axis
  123. revolution
    the earths journey around the sun
  124. axial parallelism
    the eath is tilted at an angle of 23.5 degrees
  125. how long does it take the earth to orbit the sun
  126. how many people live in the northorn hemphere
  127. the shortest and longest shortest day
    dec 21-22
  128. conduction
    the molecule to molecule transfer of heat
  129. convection
    physical mixing involving vertical motion
  130. radiation
    the transfer of heat to space via electromagnetic radiation
  131. type of light that is used for security systems
  132. reflection
    is a process where light bounces back from an object like a mirror
  133. scattering
    produces weaker rays that travels in all directions
  134. albedo
    reflecting property of a surface ex jewlery snow asphalt
  135. greenhouse effect
    light reaches the earth’s surface and the earth radiates energy back into the atmosphere
  136. greenhouse effect
    Very little of that energy escapes and the energy is trapped in the atmosphere
    Data compiled by meteorologists involve minimum, maximum and ranges of temperatures
  138. Daily Mean Temperatures
    Temperatures-Maximum and minimum temperatures / 2
  139. Daily Ranges of Temperatures
    Daily difference between min and max temp.
  140. monthly mean
    averagin daily means
  141. annual mean
    average of monthly means
  142. annual temperature range
    differenes of highest and lowest monthly means
  143. Essay Controls of temperature
    • latitude
    • altitude
    • cloud cover
    • land
    • water
  144. latitude
    as it increases the differences in yearly range of temperatures increases. The seasons are more pronounced.
  145. altitude
    • If two cities are at the same location, however, if one is at a higher location than the other, then the city with the higher location, has a more range of temperature. It
    • could be much colder or warmer.
  146. cloud cover
    have a moderating effect on the weather. They can act as beach umbrellas during the summer and as blankets during the winter.
  147. ** need examples Land and water
    • Even though two places are almost at the same latitude, but if one is situated close to a body
    • of water (Vancouver) and the other is landlocked (Winnepeg), then the one that is situated close to a body of water (Vancouver) will have a mild climate as opposed to the one that is landlocked (Winnepeg), which will have climatic extremes (very cold and extremely warm). E.g. San Francisco (next to an ocean) and Wichita (landlocked
Card Set
ch 9-12