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Core In The Earth Definition Essay

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The Earth Essay Research Paper Did u

The Earth Essay Research Paper Did u

The Earth Essay, Research Paper

Did u know that our planet, Earth wasn?t always thought of as a planet? Until the sixteenth century when Capernicus figured out that the Earth was another planet, which revolved around the sun, Greek astronomers thought the Earth was the center of the solar system. Also Earth is the only planet that its name didn?t come from Greek/Roman mythology.

When earth was first discovered, astronomers were only able to study it with out spacecraft. It was not until the twentieth century that we had maps of the entire planet. Pictures taken of the planet are very important, not only because they aid in weather predictions, but they are also very beautiful.

The Earth is divided into seven layers: the crust, upper mantle, transition region, lower mantle, D? layer, outer core, and inner core. The crust varies considerably in thickness; it is thinner under the oceans, and thicker under the continents. (Arnett1) The inner core and crust are solid, and the outer core and mantel layers are plastic or semi-fluid. Most of Earth?s mass is in its mantle and the rest is in its core.

Most of the core is made of iron, but there may be lighter elements in it too. Temperatures at the center of the core can be as high as 7500K, which is hotter than the surface of the sun.

Unlike the other rocky planets, Earth?s crust is divided into several separate plates, which float around independently on top of the hot mantle below. (Arnett1) This is called the plate tectonics theory. This is created by two processes. The first is spreading which occurs when two plates move away form each other and magma gets in, creating a new crust. The second is subduction, which is the opposite. When this happens two plates collide and one ends up being destroyed in the mantle. There are eight major plates: The North American Plate, South American Plate, Antarctic Plate, Eurasian Plate, African Plate, Indian-Australian Plate, Nazca Plate, and Pacific Plate. Other than these plates are about twenty small plates.

The surface of the Earth

4.6 billion years old, although the oldest rocks are about 4 billion years old. This is said to be rare because they are older then 3 billion years old.

Water makes up 71 percent of the Earth?s surface. Earth is also the only planet that can have water as a liquid on its surface. Water is very important on Earth because we need it to live, and without it we would be non-existent.

The Earth?s atmosphere is made up mostly of nitrogen and oxygen, but also has argon, carbon dioxide, and water. The reason there isn?t as much carbon dioxide in the Earth today is because it has turned into carbonate rocks, was dissolved into the oceans, and consumed by living plants. The carbon dioxide that remains is very important for the Earth?s surface temperature via the greenhouse effect. The greenhouse effect raised the average surface temperature about 35 degrees C above what it would otherwise be (form a frigid -21C to a comfortable +14C); without it the oceans would freeze and life as we know would be impossible. (Arnett1)

The free oxygen on Earth is outstanding. Oxygen is good because under normal circumstances it could combine in a quick manner with other elements. If we were not in existence then free oxygen wouldn?t be either.

The electric currents in the core produce Earth?s magnetic field. When the Earth?s magnetic field and upper atmosphere interact with the solar wind an auroras takes place. An aurora is a glow in a planet?s ionosphere caused by the planet?s magnetic field and charged particles form the sun. The Earth?s magnetic field and its interaction with the solar wind also produce the Van Allen radiation belts, a pair of doughnut shaped rings of ionized gas (or plasma) trapped in orbit around the Earth.

The Earth?s satellite, the moon, is its only natural satellite, but placed in orbit around the Earth are thousands of small artificial satellites.

From this report I have learned many facts about the Earth that I didn?t know before. I hope to learn as much about the other planets as I did about Earth.

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Реферат на тему The Earth Essay Research Paper Did u

The Earth Essay, Research Paper

Did u know that our planet, Earth wasn?t always thought of as a planet? Until the sixteenth century when Capernicus figured out that the Earth was another planet, which revolved around the sun, Greek astronomers thought the Earth was the center of the solar system. Also Earth is the only planet that its name didn?t come from Greek/Roman mythology.

When earth was first discovered, astronomers were only able to study it with out spacecraft. It was not until the twentieth century that we had maps of the entire planet. Pictures taken of the planet are very important, not only because they aid in weather predictions, but they are also very beautiful.

The Earth is divided into seven layers: the crust, upper mantle, transition region, lower mantle, D? layer, outer core, and inner core. The crust varies considerably in thickness; it is thinner under the oceans, and thicker under the continents. (Arnett1) The inner core and crust are solid, and the outer core and mantel layers are plastic or semi-fluid. Most of Earth?s mass is in its mantle and the rest is in its core.

Most of the core is made of iron, but there may be lighter elements in it too. Temperatures at the center of the core can be as high as 7500K, which is hotter than the surface of the sun.

Unlike the other rocky planets, Earth?s crust is divided into several separate plates, which float around independently on top of the hot mantle below. (Arnett1) This is called the plate tectonics theory. This is created by two processes. The first is spreading which occurs when two plates move away form each other and magma gets in, creating a new crust. The second is subduction, which is the opposite. When this happens two plates collide and one ends up being destroyed in the mantle. There are eight major plates: The North American Plate, South American Plate, Antarctic Plate, Eurasian Plate, African Plate, Indian-Australian Plate, Nazca Plate, and Pacific Plate. Other than these plates are about twenty small plates.

The surface of the Earth is about 4.5

4.6 billion years old, although the oldest rocks are about 4 billion years old. This is said to be rare because they are older then 3 billion years old.

Water makes up 71 percent of the Earth?s surface. Earth is also the only planet that can have water as a liquid on its surface. Water is very important on Earth because we need it to live, and without it we would be non-existent.

The Earth?s atmosphere is made up mostly of nitrogen and oxygen, but also has argon, carbon dioxide, and water. The reason there isn?t as much carbon dioxide in the Earth today is because it has turned into carbonate rocks, was dissolved into the oceans, and consumed by living plants. The carbon dioxide that remains is very important for the Earth?s surface temperature via the greenhouse effect. The greenhouse effect raised the average surface temperature about 35 degrees C above what it would otherwise be (form a frigid -21C to a comfortable +14C); without it the oceans would freeze and life as we know would be impossible. (Arnett1)

The free oxygen on Earth is outstanding. Oxygen is good because under normal circumstances it could combine in a quick manner with other elements. If we were not in existence then free oxygen wouldn?t be either.

The electric currents in the core produce Earth?s magnetic field. When the Earth?s magnetic field and upper atmosphere interact with the solar wind an auroras takes place. An aurora is a glow in a planet?s ionosphere caused by the planet?s magnetic field and charged particles form the sun. The Earth?s magnetic field and its interaction with the solar wind also produce the Van Allen radiation belts, a pair of doughnut shaped rings of ionized gas (or plasma) trapped in orbit around the Earth.

The Earth?s satellite, the moon, is its only natural satellite, but placed in orbit around the Earth are thousands of small artificial satellites.

From this report I have learned many facts about the Earth that I didn?t know before. I hope to learn as much about the other planets as I did about Earth.

FREE Reaction Paper - The Core Essay

Topics in this paper Popular Topics

The Core is a science-fiction and somehow apocalyptic film that shows how the world encounters a disastrous dilemma because the Earth's core stops rotating and loses its electromagnetic field. The Earth becomes vulnerable and tremendous disasters appear all over the world. Birds lose their ability to navigate, direct rays from the sun, electrical super storm and many more takes place when the Earth's core stops spinning. The only way to save the Earth and the people is to drill down to the core, release series of nuclear explosions and set it spinning again. A group of scientists build a ship that can overcome extreme heat in the core and accommodate them in their mission. After a lot of struggles and mishaps, losing some of their co-scientists, their mission was a success and the Earth is back to what it should be.

The Core is a sci-fi movie which means, it can be plausible or not, in this movie, I can say that it is fundamentally impossible but they make me believe that impossible can be possible. It is tricky yet its concept was well-explained in the movie. It is also an adventure with the usual thrills but with the touch of knowledgeable and more sober twist. I also acquired further learning about Earth and different scientific concepts even though sometimes, I admit that it is hard to fully accept it given that I do not have sufficient knowledge about it. I give props to those who create the scientific ideas, like the laser, the vehicle and suits that can withstand the extreme heat in the core, because it is something that I did not expect and it is refreshing in some way. The movie unfolds what science can do that hardly makes sense and allows the imagination of the audience to work and stretch. This movie makes me imagine what does the core really looks like and left me wondering what could truly be inside the Earth. In some part, scientific flaws are blatantly obvious. Example is when the people experienced sudden heat in

Essays Related to Reaction Paper - The Core

The Earth Essay Research Paper Did u

The Earth Essay Research Paper Did u

The Earth Essay, Research Paper

Did u know that our planet, Earth wasn?t always thought of as a planet? Until the sixteenth century when Capernicus figured out that the Earth was another planet, which revolved around the sun, Greek astronomers thought the Earth was the center of the solar system. Also Earth is the only planet that its name didn?t come from Greek/Roman mythology.

When earth was first discovered, astronomers were only able to study it with out spacecraft. It was not until the twentieth century that we had maps of the entire planet. Pictures taken of the planet are very important, not only because they aid in weather predictions, but they are also very beautiful.

The Earth is divided into seven layers: the crust, upper mantle, transition region, lower mantle, D? layer, outer core, and inner core. The crust varies considerably in thickness; it is thinner under the oceans, and thicker under the continents. (Arnett1) The inner core and crust are solid, and the outer core and mantel layers are plastic or semi-fluid. Most of Earth?s mass is in its mantle and the rest is in its core.

Most of the core is made of iron, but there may be lighter elements in it too. Temperatures at the center of the core can be as high as 7500K, which is hotter than the surface of the sun.

Unlike the other rocky planets, Earth?s crust is divided into several separate plates, which float around independently on top of the hot mantle below. (Arnett1) This is called the plate tectonics theory. This is created by two processes. The first is spreading which occurs when two plates move away form each other and magma gets in, creating a new crust. The second is subduction, which is the opposite. When this happens two plates collide and one ends up being destroyed in the mantle. There are eight major plates: The North American Plate, South American Plate, Antarctic Plate, Eurasian Plate, African Plate, Indian-Australian Plate, Nazca Plate, and Pacific Plate. Other than these plates are about twenty small plates.

The surface of the Earth is about 4.5

4.6 billion years old, although the oldest rocks are about 4 billion years old. This is said to be rare because they are older then 3 billion years old.

Water makes up 71 percent of the Earth?s surface. Earth is also the only planet that can have water as a liquid on its surface. Water is very important on Earth because we need it to live, and without it we would be non-existent.

The Earth?s atmosphere is made up mostly of nitrogen and oxygen, but also has argon, carbon dioxide, and water. The reason there isn?t as much carbon dioxide in the Earth today is because it has turned into carbonate rocks, was dissolved into the oceans, and consumed by living plants. The carbon dioxide that remains is very important for the Earth?s surface temperature via the greenhouse effect. The greenhouse effect raised the average surface temperature about 35 degrees C above what it would otherwise be (form a frigid -21C to a comfortable +14C); without it the oceans would freeze and life as we know would be impossible. (Arnett1)

The free oxygen on Earth is outstanding. Oxygen is good because under normal circumstances it could combine in a quick manner with other elements. If we were not in existence then free oxygen wouldn?t be either.

The electric currents in the core produce Earth?s magnetic field. When the Earth?s magnetic field and upper atmosphere interact with the solar wind an auroras takes place. An aurora is a glow in a planet?s ionosphere caused by the planet?s magnetic field and charged particles form the sun. The Earth?s magnetic field and its interaction with the solar wind also produce the Van Allen radiation belts, a pair of doughnut shaped rings of ionized gas (or plasma) trapped in orbit around the Earth.

The Earth?s satellite, the moon, is its only natural satellite, but placed in orbit around the Earth are thousands of small artificial satellites.

From this report I have learned many facts about the Earth that I didn?t know before. I hope to learn as much about the other planets as I did about Earth.

Overview of Geothermal Energy - #1 - Free Online Essays and Research Papers, Term Papers

Overview of Geothermal Energy

As we look to alternative energy sources for our power hungry world, geothermal energy is getting attention. Here is a brief overview of geothermal energy.

Overview of Geothermal Energy

There are many different types of energy available to power our world. For years, people have used the power of burning fossil fuels, such as coal (also used to produce steam power) to create energy. In recent times, there has been a shift to using renewable resources to create the energy we need. These resources include hydroelectric power, solar power, wind power, biomass energy and geothermal energy. While many people know about the first four of these resources, geothermal energy is less well-known.

The word geothermal comes from two Greek words, “geo” and “therme”. These words mean “earth” and “heat”, which pretty much describes what geothermal energy is. Geothermal energy is energy that comes from the heat of the Earth, deep underground. The Earth's core, where chemical reactions create massive amounts of heat, is 4,000 miles below the Earth's surface. In this core, temperatures can reach up to 9,000 degrees Fahrenheit, and this extreme heat can be used to produce energy.

While these are the basics of geothermal energy, there are many other parts in the process to make this sort of energy usable. We can't tap directly into the Earth's core to receive this heat, for many reasons. So instead, people must create systems that harness the residual heat that is in the magma (molten rock) under the Earth's crust. This heat is able to be used by tapping into the water reservoirs that are within the magma – these water stores can reach up to 700 degrees Fahrenheit. Think of Old Faithful in Yellowstone.

A well can be drilled down into the superheated water contained within the Earth's magma - the geothermal reservoir. Once these geothermal reservoirs are tapped into, the heated water and steam can rise to the surface, and be used to power geothermal power plants as well as in smaller scale projects for personal household use. When used in geothermal power plants, the steam from the heated underground water is often used to power turbines, which then generate energy which can be harnessed as electricity.

By using the Earth's own heat and water, energy can be created that can be used on a small or large scale. This renewable resource (you can't deplete the Earth's heat!) is also cleaner and safer than many other types of energy, making it a great type of ecologically sound energy source.

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Structure_of_the_Earth: definition of Structure_of_the_Earth and synonyms of Structure_of_the_Earth (English)

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definition - Structure_of_the_Earth Structure of the Earth

Earth cutaway from core to exosphere. Left picture is not to scale.

The interior structure of the Earth is layered in spherical shells, like an onion. These layers can be defined by either their chemical or their rheological properties. The Earth has an outer silicate solid crust. a highly viscous mantle. a liquid outer core that is much less viscous than the mantle, and a solid inner core. Scientific understanding of Earth's internal structure is based on observations of topography and bathymetry. observations of rock in outcrop. samples brought to the surface from greater depths by volcanic activity, analysis of the seismic waves that pass through the Earth, measurements of the gravity field of the Earth, and experiments with crystalline solids at pressures and temperatures characteristic of the Earth's deep interior.

Contents Assumptions

The force exerted by Earth's gravity can be used to calculate its mass, and by estimating the volume of the planet, its average density can be calculated. Astronomers can also calculate Earth's mass from its orbit and effects on nearby planetary bodies. Observations of rocks, bodies of water and atmosphere allow estimation of the mass, volume and density of rocks to a certain depth, so the remaining mass must be in the deeper layers.

Structure

Earth's radial density distribution according to the preliminary reference earth model (PREM).

Earth's gravity according to the preliminary reference earth model (PREM). Comparison to approximations using constant and linear density for Earth's interior.

The structure of Earth can be defined in two ways: by mechanical properties such as rheology. or chemically. Mechanically, it can be divided into lithosphere. asthenosphere. mesosphere. outer core. and the inner core. The interior of the earth is divided into 5 important layers. Chemically, Earth can be divided into the crust, upper mantle, lower mantle, outer core, and inner core. The geologic component layers of Earth [ 1 ] are at the following depths below the surface:

Mapping the interior of the Earth with earthquake waves.

The layering of Earth has been inferred indirectly using the time of travel of refracted and reflected seismic waves created by earthquakes. The core does not allow shear waves to pass through it, while the speed of travel (seismic velocity ) is different in other layers. The changes in seismic velocity between different layers causes refraction owing to Snell's law. Reflections are caused by a large increase in seismic velocity and are similar to light reflecting from a mirror.

Core

The average density of Earth is 5,515 kg /m 3. Since the average density of surface material is only around 3,000 kg/m 3. we must conclude that denser materials exist within Earth's core. Further evidence for the high density core comes from the study of seismology .

Seismic measurements show that the core is divided into two parts, a solid inner core with a radius of

1,220 km [ 2 ] and a liquid outer core extending beyond it to a radius of

3,400 km. The solid inner core was discovered in 1936 by Inge Lehmann and is generally believed to be composed primarily of iron and some nickel. In early stages of Earth's formation about 4.5 billion (4.5 × 10 9 ) years ago, melting would have caused denser substances to sink toward the center in a process called planetary differentiation (see also the iron catastrophe ), while less-dense materials would have migrated to the crust. The core is thus believed to largely be composed of iron (80%), along with nickel and one or more light elements, whereas other dense elements, such as lead and uranium. either are too rare to be significant or tend to bind to lighter elements and thus remain in the crust (see felsic materials ). Some have argued that the inner core may be in the form of a single iron crystal. [ 3 ] [ 4 ]

On August 30, 2011, Professor Kei Hirose, professor of high-pressure mineral physics and petrology at the Tokyo Institute of Technology, became the first person to recreate conditions found at the earth's core under laboratory conditions, subjecting a sample of iron nickel alloy to the same type of pressure by gripping it in a vise between 2 diamond tips, and then heating the sample to approximately 4000 Kelvins with a laser. The sample was observed with x-rays, and strongly supported the theory that the earth's inner core was made of giant crystals running north to south. [ 5 ] [ 6 ]

The liquid outer core surrounds the inner core and is believed to be composed of iron mixed with nickel and trace amounts of lighter elements.

Recent speculation suggests that the innermost part of the core is enriched in gold. platinum and other siderophile elements. [ 7 ]

The matter that comprises Earth is connected in fundamental ways to matter of certain chondrite meteorites, and to matter of outer portion of the Sun. [ 8 ] [ 9 ] There is good reason to believe that Earth is, in the main, like a chondrite meteorite. Beginning as early as 1940, scientists, including Francis Birch. built geophysics upon the premise that Earth is like ordinary chondrites, the most common type of meteorite observed impacting Earth, while totally ignoring another, albeit less abundant type, called enstatite chondrites. The principal difference between the two meteorite types is that enstatite chondrites formed under circumstances of extremely limited available oxygen, leading to certain normally oxyphile elements existing either partially or wholly in the alloy portion that corresponds to the core of Earth.

Dynamo theory suggests that convection in the outer core, combined with the Coriolis effect. gives rise to Earth's magnetic field. The solid inner core is too hot to hold a permanent magnetic field (see Curie temperature ) but probably acts to stabilize the magnetic field generated by the liquid outer core. The average magnetic field strength in the Earth's outer core is estimated to be 25 Gauss, 50 times stronger than the magnetic field at the surface. [ 10 ] [ 11 ]

Recent evidence has suggested that the inner core of Earth may rotate slightly faster than the rest of the planet. [ 12 ] In August 2005 a team of geophysicists announced in the journal Science that, according to their estimates, Earth's inner core rotates approximately 0.3 to 0.5 degrees per year relative to the rotation of the surface. [ 13 ] [ 14 ]

The current scientific explanation for the Earth's temperature gradient is a combination of heat left over from the planet's initial formation, decay of radioactive elements, and freezing of the inner core.

Mantle

Schematic view of the interior of Earth. 1. continental crust – 2. oceanic crust – 3. upper mantle – 4. lower mantle – 5. outer core – 6. inner core – A: Mohorovičić discontinuity – B: Gutenberg Discontinuity – C: Lehmann–Bullen discontinuity

Earth's mantle extends to a depth of 2,890 km, making it the thickest layer of the Earth. The pressure. at the bottom of the mantle, is

140 GPa (1.4 Matm ). The mantle is composed of silicate rocks that are rich in iron and magnesium relative to the overlying crust. Although solid, the high temperatures within the mantle cause the silicate material to be sufficiently ductile that it can flow on very long timescales. Convection of the mantle is expressed at the surface through the motions of tectonic plates. The melting point and viscosity of a substance depends on the pressure it is under. As there is intense and increasing pressure as one travels deeper into the mantle, the lower part of the mantle flows less easily than does the upper mantle (chemical changes within the mantle may also be important). The viscosity of the mantle ranges between 10 21 and 10 24 Pa·s. depending on depth. [ 15 ] In comparison, the viscosity of water is approximately 10 −3 Pa·s and that of pitch is 10 7 Pa·s.

Crust

The crust ranges from 5–70 km in depth and is the outermost layer. The thin parts are the oceanic crust. which underlie the ocean basins (5–10 km) and are composed of dense (mafic ) iron magnesium silicate rocks. like basalt .The thicker crust is continental crust. which is less dense and composed of (felsic ) sodium potassium aluminium silicate rocks, like granite. The rocks of the crust fall into two major categories – sial and sima (Suess,1831–1914). It is estimated that sima starts about 11 km below the Conrad discontinuity (a second order discontinuity). The uppermost mantle together with the crust constitutes the lithosphere. The crust-mantle boundary occurs as two physically different events. First, there is a discontinuity in the seismic velocity, which is known as the Mohorovičić discontinuity or Moho. The cause of the Moho is thought to be a change in rock composition from rocks containing plagioclase feldspar (above) to rocks that contain no feldspars (below). Second, in oceanic crust, there is a chemical discontinuity between ultramafic cumulates and tectonized harzburgites. which has been observed from deep parts of the oceanic crust that have been obducted onto the continental crust and preserved as ophiolite sequences .

Many rocks now making up Earth's crust formed less than 100 million (1 × 10 8 ) years ago; however, the oldest known mineral grains are 4.4 billion (4.4 × 10 9 ) years old, indicating that Earth has had a solid crust for at least that long. [ 16 ]

Historical development of alternative conceptions

In 1692 Edmund Halley (in a paper printed in Philosophical Transactions of Royal Society of London ) put forth the idea of Earth consisting of a hollow shell about 500 miles thick, with two inner concentric shells around an innermost core, corresponding to the diameters of the planets Venus, Mars, and Mercury respectively. [ 17 ] Halley's construct was a method of accounting for the (flawed) values of the relative density of Earth and the Moon that had been given by Sir Isaac Newton. in Principia (1687). "Sir Isaac Newton has demonstrated the Moon to be more solid than our Earth, as 9 to 5," Halley remarked; "why may we not then suppose four ninths of our globe to be cavity?" [ 17 ]

See also

Inaccurate Definitions - Responding To Creationism

Inadequate and Contradictory Definitions and Descriptions of Actualism and Other Terms in Oard and Reed (2009)

Kevin R. Henke, Ph.D.

A Few Examples from the Deficient Glossary in Oard and Reed (2009)

If geologists and young-Earth creationists (YECs) are ever going to effectively communicate their ideas to each other, they must agree on appropriate definitions for actualism, uniformitarianism and other geologic terms. One of the major problems with Oard and Reed (2009) is that this document misdefines or defines terms differently than the mainstream geologic literature. In particular, Oard and Reed (2009) contains a glossary with definitions that are often deficient or inaccurate. In other cases, key YEC terms (such as diluvialism and supernaturalism) are not even included in the Oard and Reed (2009) glossary. "Diluvialist" is present (Oard and Reed 2009, p. 263), but the definition is woefully inadequate:

“a person who accepts the historical reality of the Genesis Flood as a presupposition to earth science studies.”

Under this poor and vague definition, the famous catastrophist Georges Cuvier would be considered a “diluvialist.” Yet, Cuvier was a “heretic” by modern young-Earth creationist (YEC) standards. He advocated an ancient Earth and believed in multiple worldwide floods in the Earth's past, where the last one was Noah's (Young 1982, p. 50). Since the Oard and Reed (2009) definition also does not indicate that Earth science studies need to be global rather than regional or local, or that all or nearly all of the Earth's sedimentary rocks need to have been deposited by the Flood, this poor definition of diluvialist could include individuals that believe that Genesis teaches an historical and geologically significant, but regional, Noah's Flood. That is, this vague definition of diluvialist could include theistic evolutionist and evangelical Christian Glenn Morton. who is frequently criticized in Oard and Reed (2009). I don't think that Mr. Oard and Dr. Reed would want Mr. Morton in their “diluvialist” group. Furthermore, the definition says nothing about natural or supernatural processes being involved in the “Genesis Flood.” Was the supernatural involved? If not, why not? If so, how common were miracles and what's the scientific evidence for them? The Bible claims that God miraculously parted the sea for Moses (Exodus 14) and that Jesus walked on water (Mark 6:45-52), so why wouldn't YECs expect God to miraculously create and move the Flood waters? Now, YECs might shy away from advocating miracles if these miracles are not specifically mentioned in the Bible. However, a total lack of biblical references to a post-Flood "ice age" and many other supposed events does not keep most YECs from advocating their existence. Young-Earth creationism is hopelessly inconsistent and subjective.

Inadequate Definition of Actualism in Oard and Reed (2009) Glossary

Oard (2009a, p. 114) accuses me of not providing a precise definition of actualism in my 1999 essay. However, I would argue that the discussions and examples in my 1999 essay were suitable and far more detailed than the brief two sentence “precise” glossary definition of actualism given in Oard and Reed (2009, p. 262). Because Oard (2009a) wants more details from me on actualism, I further describe what actualism is and is not in “Actualism (Modern Uniformitarianism) and its Assumptions. ”

Rather than appropriately basing their definition of actualism on the geologic literature (e.g.. Dott and Batten 1988, p. 39; Strahler 1999 and more recent references) and how geologists actually perform their field and laboratory work, the Oard and Reed (2009, p. 262) definition of actualism reads:

“the modification of the principle of uniformitarianism that accepts the rates of some processes might have been higher at times in the past, or that environmental conditions may have been different. Although these processes are not observed today, they still must be 'plausible natural process'“[sic ].

Although glossaries are nice, sometimes complex concepts (such as actualism) cannot be adequately summarized in two sentence definitions. Although Oard (2008b, p. 6) and Oard (2009a, p. 111) derided my “definition” (description) of actualism in my 1999 essay as "unusual" and weak, he and Dr. Reed obviously thought enough of it to try to incorporate some of its concepts into their grammatically awkward glossary definition. Overall, however, their definition of actualism is still woefully inadequate and inaccurate. For example, Oard and Reed (2009, p. 262) claim that actualism is a “modification” of uniformitarianism. While actualism is a modification of Lyell uniformitarianism, I don't see geologists widely proclaiming that actualism is a modification of modern uniformitarianism. To the contrary, most geologists essentially equate modern uniformitarianism with actualism (Judson and Richardson 1995, p. 2; Mintz 1977, p. 5, 7; McGeary et al. 2004, p. 190, etc.), and that is the approach that I take. When Oard and Reed (2009, p. 262) state that natural “processes are not observed today”, this is not always correct. Under actualism, geologists do not expect modern analogs for every ancient process that formed the geologic record, but we still look for modern analogs and use them if they are found. That is, depending on the situation, modern analogs may or may not exist. Furthermore, while the Oard and Reed (2009) definition of actualism correctly states that the rates of some processes may have been higher in the past than today, why couldn't the rate of a natural process (such as erosion) have been lower at a given time in the past or varied in intensity over geologic time? Why is the possibility of lower and variable rates not mentioned in the Oard and Reed (2009) definition? In reality, the geologic record is the product of both natural catastrophes and long and slow natural processes. Furthermore, the rate of a natural process at a given location could have been much higher or lower at a given time in the past.

Inaccurate Definition of Modern Uniformitarianism in Oard and Reed (2009): Modern Uniformitarianism (Actualism) does NOT Require Modern Analogs

Rather than equating actualism with modern uniformitarianism as is commonly done in geology textbooks and other geology documents (Judson and Richardson 1995, p. 2; Mintz 1977, p. 5, 7; McGeary et al. 2004, p. 190, etc.), Oard and Reed (2009, p. 266) derive a separate and inaccurate definition for modern uniformitarianism that is significantly different than their definition of actualism:

“the fundamental doctrine of modern geology that believes that the rock record can be interpreted by reference to observed modern processes. In its earlier forms, advocates insisted on a strict uniformity of rates as well as processes.”

So, under this definition, what would Oard and Reed (2009) say to the “uniformitarians” if no “observed modern processes” (modern analogues) could be found to interpret an outcrop? Statements in Reed and Oard (2009a, p. 13), Silvestru (2009, p. 47) and elsewhere in Oard and Reed (2009) indicate that these YECs believe that “modern uniformitarianism” requires the presence of modern analogs to function. As further discussed below, the authors of Oard and Reed (2009) have deliberately set up invalid and inconsistent strawperson definitions of “uniformitarianism” and “actualism” that are so flawed that they hope that people will readily reject them and embrace young-Earth creationism. A common tactic by some individuals is to try to discredit their opponents' procedures by misdefining the procedures and weighing them down with unnecessary, outdated and easily refuted "requirements." T he Oard and Reed (2009) definition of modern uniformitarianism is also not any better than the following extremely vague definition given in Oard (2005, p. 167):

“The principle that processes similar to those observed today are responsible for the rocks and fossils.”

Contrary to the definitions in Oard and Reed (2009, p. 266) and Oard (2005, p. 167), and discussions in Oard (1997), Oard (2009a, p. 113-114), Silvestru (2009, p. 47) and elsewhere in Oard and Reed (2009), modern uniformitarianism (= actualism) does not require the use of “observed modern processes” (modern analogs) to derive explanations for the geologic record. The traditional saying "The presence is the key to the past" is not an absolute rule. Certainly, geologists using modern uniformitarianism will always seek modern analogs to better understand past events. However, if modern analogs are not available, geologists can still decipher past environments by carefully looking for clues in the outcrops and using logical deductions, setting up experimental replicas, performing other laboratory experiments, studying conditions on other planets and moons, and/or through computer modeling. The gross mischaracterization of modern uniformitarianism in Oard and Reed (2009) is clearly refuted by the following statements from YEC Austin (1979, p. 39), where he summarizes the long ago realizations of Shantser (1970), Dott and Batten (1971) and Valentine (1973):

“The geologist's technique in deciphering ancient processes, they [Shantser (1970), Dott and Batten (1971) and Valentine (1973)] affirm, relies not only on analogies with products from experimental replicas and other non-geological systems, and on logical deductions from theories or scientific laws. Proper interpretations of ancient processes should, they say, involve complex techniques of inference, not just simple one-to-one association of products of modern and ancient processes. By using complex inference techniques, the geologist retains the maximum flexibility when conception of which is probably the crucial step in the act of scientific discovery.” [my emphasis]

Yet, Oard (1997, pp. 25, 38, 55, 84, etc.), Oard (2009a, p. 114), Oard (2009b, p. 138) and elsewhere in Oard and Reed (2009) contain many examples of trying to discredit pre-Pleistocene iceberg scour marks and other features in the geologic record by invoking fallacious strawperson definitions of modern uniformitarianism that obviously involve “simple one-to-one associations of products of modern and ancient processes.” Contrary to what Oard and Reed (2009) suggest, geologists do not believe that ancient geological processes should be cookie-cutterreplicas of modern processes.

The following are some additional quotations from a few common geology textbooks that Mr. Oard and Dr. Reed should review. These quotations argue that modern uniformitarianism does not require and cannot always develop hypotheses based on “observed modern processes”:

Levin (2010, p. 19) states:

“At the same time, we must be constantly aware that in the past, the rates of change and intensity of processes often varied from those we are accustomed to seeing today, and that some events of long ago simply have no modern counterpart .” [my emphasis]

Press and Siever (2001, p. 4) conclude:

“We now know that many important geologic processes are not observable in action today, yet the evidence that they took place is undeniable. For example, there have been asteroid impacts that no human witnessed but that greatly modified the Earth's crust and climate in the past. Neither has humankind seen the vast volcanic outpourings of the past in which lava covered areas of continental dimensions and volcanic gases poisoned the global atmosphere [i.e. the end of the Permian].”

Strahler (1999, p. 215) argues:

“Mainstream geologists do not claim that the world of today contains examples of recent formation of everything that has ever happened in all of geologic time.”

Furthermore, the natural processes that occur today may not always be detected in the geologic record either because they left no discernible evidence or they did not always occur in the past. For example, the widespread presence of subtropical vegetation at high latitudes during at least parts of the Eocene indicates that glaciers and glacial processes may have been totally absent from the Earth at those times.

If Mr. Oard and Dr. Reed are really familiar with these statements from Strahler (1999), the references in Austin (1979) and even more recent textbooks that are used to train future geologists, then what justification do they have for arguing that modern uniformitarianism requires the use of “observed modern processes” to interpret the geologic record? Since modern analogs don't exist for banded iron formations, how would geologists ever understand the formation of these rocks without relying on laboratory experiments and computer modeling? How can Oard (2009a, p. 113) dare to claim that YECs “understand uniformitarian arguments quite well” when the geology literature shows that he and other YECs commonly do not? I think that Mr. Oard and Dr. Reed in Oard and Reed (2009) are simply attempting to discredit modern uniformitarianism by weighing it down with an unnecessary assumption for modern analogs so that they and other YECs can more easily ridicule it whenever no obvious modern analogs are available.

Examples of Mistaken Demands for Modern Analogs in Mr. Oard's Documents

Oard (1997) and Oard and Reed (2009) contain many erroneous claims about modern uniformitarianism (actualism) requiring modern analogs. Mr. Oard’s mischaracterizations of actualism are classic examples of strawperson fallacies, where he attempts to put invalid restrictions on modern uniformitarianism (actualism) so that it can be more easily ridiculed and somehow made to look inferior to Flood geology, a 6,000 year old Earth and stories involving a talking snake and magic fruit trees. For example, Oard (2009a, p. 114) still cannot accept the fact that iceberg scour marks, debris flow deposits, and other features in pre-Pleistocene glacial deposits may have had different sizes or poorer preservation than the same types of features in Pleistocene and modern glacial deposits. He refers to my protests against Oard (1997) in my 1999 essay as “special pleading” because he just can't accept the idea that other geologists and I don't expect pre-Pleistocene glacial deposits to be cookie-cutter replicas of modern glacial features. Oard (2009a, p. 114) also calls my reliance on actualism as an “excuse” when he states:

“He [Dr. Henke in his 1999 essay] (p. 69) uses the same excuse to avoid the absence of huge debris flow deposits in pre-Pleistocene strata, while large debris flows are common in Pleistocene and modern sediments.”

Mr. Oard is probably referring to this paragraph from my 1999 essay.

“According to Oard ([1997], p. 38), large debris flows are common in modern sediments, but are nearly absent in the pre-Pleistocene record. Oard ([1997], p. 38) claims that this observation somehow violates 'uniformitarianism.' Oard has created an invalid 'no lose' situation for himself. If modern debris flows are generally larger than ancient analogs, he can attack the strawperson doctrine of Lyell uniformitarianism and claim that modern deposits are not good analogies of ancient ones. If the modern deposits happened to be generally absent or smaller than the ancient examples, Oard could always invoke Noah's Flood as the unique cause of the larger scale, ancient features. In reality, Oard is simply failing to realize that ancient deep marine debris flows would most likely be subducted or deeply buried under more marine sediments rather than obducted and preserved on continents where geologists could readily find them.”

As long as no natural laws were violated, there is no reason why one or more debris flow deposits, iceberg scour marks or other surviving pre-Pleistocene glacial features may not be significantly smaller or larger than those in Pleistocene and modern deposits. Differences in the sizes of modern and ancient sedimentary features do not eliminate pre-Pleistocene glaciations, invalidate the investigative approach of actualism or in any way indicate that supernatural events or a nonglacial global Noah's Flood was involved. The sizes of these features would depend upon local conditions and the amount destruction from erosion. Rather than trying to understand the diversity of the geologic record, Mr. Oard obviously mistakenly believes that he can somehow promote Flood geology and invalidate actualism and pre-Pleistocene glaciations by relying on inconsequential differences between modern and pre-Pleistocene deposits.

There are also numerous examples in Oard (1997), where he mistakenly believes that actualism demands that features found in modern environments must also occur in ancient environments (e.g.. pockmarks on the ocean floor; Oard, 1997, p. 26) or that actualism somehow requires that that every process that produced a rock type in the geologic record must also be present in modern environments (e.g.. thick dolostone beds, Oard, 1997, p. 28). Strahler (1999), Levin (2010), Press and Siever (2001), and other geologic literature clearly show that Mr. Oard is only punching a strawperson in a fruitless and desperate attempt to attack actualism.

Oard (2009a) Inconsistently Uses His Own Definition of Uniformitarianism

As stated above, I along with many other geologists (e.g. Judson and Richardson 1995, p. 2; Mintz 1977, p. 5, 7; McGeary et al. 2004, p. 190) equate actualism with modern uniformitarianism. In contrast, Oard and Reed (2009, pp. 262, 266) went to the unusual effort to create incompatible and erroneous definitions for these two terms. After deriving separate definitions for actualism and uniformitarianism, Oard (2009a, p. 111, 112, 113, 117, 119, 120, etc.) repeatedly ignores his own definitions and uses the words actualism and uniformitarianism interchangeably when referring to me and my work! Although Oard (2009a, pp. 113-114) recognizes that I endorse actualism as the basis of modern geology, Oard (2009a) refers to me as having an “uniformitarian position” (p. 111), that Rampino is my “fellow uniformitarian” (p. 119), and he states “uniformitarian scientists, including Henke” (p. 120). These references to me would be fine, if Oard and Reed (2009) had properly defined actualism and modern uniformitarianism as synonyms as other geologists and I do. However, how can I be an “uniformitarian” under Mr. Oard's definition of the term in Oard and Reed (2009, p. 266) when I clearly stated in my 1999 essay that the geologic record is not always “interpreted by reference to observed modern processes”? The unwillingness of Oard (2009a) to consistently rely on the very glossary definitions that he helped to create firmly shows how muddled his thinking is about geology and how little confidence he really has in his own definitions of geologic terms.

References (Note: Lettering with reference years is consistent with the references in other essays at this website.)

Austin, S.A. 1979. “Uniformitarianism- A Doctrine that Needs Rethinking”, The Compass. v. 56, n. 2, pp. 29-45.

Dott, R.H. and R. L. Batten. 1971. Evolution of the Earth. McGraw-Hill Book Co. New York, 649pp.

Dott, R.H. and R. L. Batten. 1988. Evolution of the Earth. 4th edition, McGraw-Hill Book Co. New York, 684pp.

Judson, S. and S.M. Richardson. 1995. Earth: An Introduction to Geologic Change. Prentice Hall, Englewood Cliffs, New Jersey, USA, 551pp.

Levin, H. 2010. The Earth through Time. 9th edition, John Wiley & Sons, Inc. New York, 606pp.

McGeary, D. C.C. Plummer, and D.H. Carlson. 2004. Physical Geology: Earth Revealed. 5th edition, McGraw Hill, Boston, 574pp.

Mintz, L.W. 1977. Historical Geology: The Science of a Dynamic Earth. 2nd edition, Charles E. Merrill Publishing Company, Columbus, Ohio, USA, 588pp.

Oard, M.J. 1997. Ancient Ice Ages or Gigantic Submarine Landsides? Creation Research Society, Monograph No. 5, Chino Valley, AZ.

Oard, M.J. 2005. The Frozen Record: Examining the Ice Core History of the Greenland and Antarctic Ice Sheets. Institute for Creation Research, Santee, California, USA, 199pp.

Oard, M.J. 2008b. "The Eocene Ice Age - Example of a Geological Challenge," Creation Matters. v. 13, n. 6, Nov.-Dec. pp. 1, 6-8.

Oard, M.J. 2009a. “Landslides Win in a Landslide over Ancient 'Ice Ages'“, chapter 7 in M.J. Oard and J.K. Reed (editors). 2009. Rock Solid Answers: The Biblical Truth Behind 14 Geological Questions. Master Books: Green Forest, AR, pp. 111-123.

Oard, M.J. 2009b. "Do Varves Contradict Biblical History?", chapter 8 in M.J. Oard and J.K. Reed (editors). 2009. Rock Solid Answers: The Biblical Truth Behind 14 Geological Questions. Master Books: Green Forest, AR, pp. 125-148.

Oard, M.J. and J.K. Reed (editors). 2009. Rock Solid Answers: The Biblical Truth Behind 14 Geological Questions. Master Books: Green Forest, AR, 272 pp.

Press, F. and R. Siever. 2001. Understanding Earth. 3rd edition, W.H. Freeman and Company, New York, USA, 625pp.

Reed, J.K. and M.J. Oard. 2009a. "A Context for the Flood Geology Debate," chapter 1 in M.J. Oard and J.K. Reed (editors). 2009. Rock Solid Answers: The Biblical Truth Behind 14 Geological Questions. Master Books: Green Forest, AR, pp. 11-17.

Shantser, Y.V. 1970. “On the Methodology of Research in Historical Geology”, Geotectonics. v. 4, pp. 69-74.

Silvestru, E. 2009. “Karst and the Age of the World”, chapter 4 in M.J. Oard and J.K. Reed (editors). 2009. Rock Solid Answers: The Biblical Truth Behind 14 Geological Questions. Master Books: Green Forest, AR, pp. 45-61.

Strahler, A.N. 1999. Science and Earth History- The Evolution/Creation Controversy. Prometheus Books, Amherst, New York, USA, 552pp.

Valentine, J.W. 1973. Evolutionary Paleoecology of the Marine Biosphere. Prentice Hall, Englewood Cliffs, NJ, 511pp.

Young, D.A. 1982. Christianity & The Age of the Earth. Zondervan Publishing House, Grand Rapids, Michigan, USA, 188pp.