2 earth science questions?
951858
Evaporites (IPA: /iˈvapərʌɪt/) are water-soluble, mineral sediments that result from the evaporation of bodies of surficial water.\n\nEvaporites are formed by evaporation of restricted bodies of water at the Earth's surface.\n\nAlthough all water bodies on the surface and in aquifers contain dissolved salts, in order to form minerals from these salts, the water must evaporate into the atmosphere in order to precipitate the minerals.\n\nIn order for this to happen the water body must enter a restricted environment where water input into this environment remains below the net rate of evaporation. This is usually an arid environment with a small basin fed by a limited input of water.\n\n--> http://en.wikipedia.org/wiki/Evaporite#Evaporitic_formations\n\nSedimentary rocks are laid down in layers called beds or strata. Each new layer is laid down horizontally over older ones. There are usually some gaps in the sequence called unconformities. These represent periods in which no new sediments were being laid down, or when earlier sedimentary layers were raised above sea level and eroded away.\n\n--> http://en.wikipedia.org/wiki/Sedimentary_rocks
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Try http://www.geo.lsa.umich.edu/~crlb/COURSES/270/Lec12/Lec12.html\nIt helped me do my homework! Also, it has pictures of plate boundries and plate tectonics. Hope it helps!
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1. Continental drift or plate tectonics.\n\n2. Horizontal fault line.
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1. Water (surface run-off, streams, rivers, sea currents, etc), Wind and Gravity\n2. Seas, lakes, rivers, estuaries etc\n3. Compaction.\n4. Cementation.
652500
Answer A) Small size & rocky surfaces
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1) Widespread Terratoriality.\n2) Global Warming.\n\n#1 is like going places man wasn't supposed to go..like space, and the deep ocean, and even underground..\n#2 is very self-explainatory.\n\nNitrogen.
164527
2 points to me for foolish questions!
195201
i think u typed the question wrong, can u please correct it and if u have 2 unknowns, please give 2 equations, else u cant get a definite solution
110846
Particulates from 'smoke'.\nSoil that has been eroded by the wind.\nSalt crystals lifted off the sea.\nPollen\nSeeds from plants such as dandelionor orchids.\nWindborne microbes or their spores.\nAnimals, mainly birds and insects, but also spiders and other animals that are blown from place to place.\n\n\n________\n\n>>>> none they are all gases\n\nYeah, like all the material in the ocean is a liquid, right? And all the material in the ground is a solid?\n\nDid you even stop to think before answering?
556019
thats 2 questions & i dont understand either of them
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Here's a nice explanation:\nhttp://www.4to40.com/QA/index.asp?counter=382&category=science
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try http://earth.google.com
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Okay I think the other 2 answers you already had when I started this misunderstood your question so I'll get it right for you.\n\nTwo things happen in the 16 seconds.\n1. rock falls s meters\n2. sound travels back up s meters from water surface to well opening\n\nFirst let's deal with the #1 part, the rock's fall.  For this let's use a variable called t1 for time.\n\nWe need to use this formula: s = (v1)(t) + ½(a)(t)²\ns = displacement, v1 = initial velocity, t=time, a=acceleration\n\nSince the rock is dropped it has no initial velocity.  Let down be positive.\n\ns = (v1)(t1) + ½(a)(t1)²\ns = (0)(t1) + ½(a)(t1)²\ns = ½(a)(t1)²\n\nOkay so we figured out what we can in this step about t1.  Now let's go to step 2 and see what we can figure out about t2.\n\nThe sound travelled from the water up to the well opening (s meters) in some amount of time we don't know yet (t2).  We can describe the sound's movement with this formula:\n\ns = (v)(t) (we use this because the sound is not accelerating)\n\ns = displacement, v = velocity, t = time\n\nNow let's use our variables (t2, our s) and use v2 for the sound's velocity and see what we can put together with the sound.\n\ns = (v2)(t2)\n\nOkay so we know something about the sound and rock now, let's gather what we found and look at it.\n\n1. s = ½(a)(t1)²\n2. s = (v2)(t2)\n\nThere is something else we know too and can write down as an equation.  We know that the time it took for the rock to hit the water and the time it took for the sound of the splash to travel back up to the opening add up to a total of 16 seconds.  So we can write it as:\n\nt1 + t2 = 16s (let's isolate the t2 and call it equation 3)\n3. t2 = 16 - t1\n\nSo all together we have:\n\n1. s = ½(a)(t1)²\n2. s = (v2)(t2)\n3. t2 = 16 - t1\n\nWe have enough equations now to solve for the number of variables we have.  Start by substituting t2 from #3 into #2 to get equation #4.\n\n4. s = (v2)(16 - t1)\n\nNow set 1. and 4. equal to each other (because they are both s so they are equal so we can do that)\n\n(v2)(16 - t1) = ½(a)(t1)²       (expand it out now)\n\n16(v2)-(t1)(v2) = ½(a)(t1²)\n\nNow put in what we know (v2 = 345m/s, a = 9.8m/s)\n\n16(345)-(t1)(345) = 4.9(t1²)   (move it all to one side and it should look familiar)\n\n4.9t1²+345t1-5520=0  (it's a quadratic equation and we can solve those, stick it in your calculator)\n\nt1 solves to\nt1 = 13.436\nor\nt1 = -83.844 (forget this one, the rock didn't hit before you dropped it)\n\nSo t1 = 13.436m (we only know this to 2 significant digits)\n\nNow we can finally solve for s by using equation #1\n1. s = ½(a)(t1)²\ns = ½(9.8)(13.436)²\ns = 884.57m (only to two sig. digits)\n\ns = 880 meters
509040
The Earth is not Hollow. Below the 60 Km crust is the semi-liquid Mantle. The core at the center is Solid.
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1.27 X 1022 KG (0.0021 Earths)
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It's widely believed in the scientific community that the earth has a liquid mantle (that's where magma/lava comes from) and a solid super-hot iron core.  Good luck digging through that.
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4600 Formation of the approximately homogeneous solid Earth by planetesimal accretion  \n4300 Melting of the Earth due to radioactive and gravitational heating which leads to its differentiated interior structure as well as outgassing of molecules such as water, methane, ammonia, hydrogen, nitrogen, and carbon dioxide  \n4300 Atmospheric water is photodissociated by ultraviolet light to give oxygen atoms which are incorporated into an ozone layer and hydrogen molecules which escape into space  \n4000 Bombardment of the Earth by planetesimals stops  \n3800 The Earth's crust solidifies--formation of the oldest rocks found on Earth  \n3800 Condensation of atmospheric water into oceans  \n3500-2800 Prokaryotic cell organisms develop  \n3500-2800 Beginning of photosynthesis by blue-green algae which releases oxygen molecules into the atmosphere and steadily works to strengthen the ozone layer and change the Earth's chemically reducing atmosphere into a chemically oxidizing one  \n2400 Rise in the concentration of oxygen molecules stops the deposition of uraninites (since they are soluble when combined with oxygen) and starts the deposition of banded iron formations  \n2000 The Oklo natural fission reactor in Gabon goes into operation  \n1600 The last reserves of reduced iron are used up by the increasing atmospheric oxygen--last banded iron formations  \n1500 Eukaryotic cell organisms develop  \n1500-600 Rise of multicellular organisms  \n580-545 Fossils of Ediacaran organisms are made  \n545 Cambrian explosion of hard-bodied organisms  \n528-526 Fossilization of the Chengjiang site  \n517-515 Fossilization of the Burgess Shale  \n500-450 Rise of the fish--first vertebrates  \n430 Waxy coated algae begin to live on land  \n420 Millipedes have evolved--first land animals  \n375 The Appalachian mountains are formed via a plate tectonic collision between North America, Africa, and Europe  \n375 Appearance of primitive sharks  \n350-300 Rise of the amphibians  \n350 Primitive insects have evolved  \n350 Primitive ferns evolve--first plants with roots  \n300-200 Rise of the reptiles  \n300 Winged insects have evolved  \n280 Beetles and weevils have evolved  \n250 Permian period mass extinction  \n230 Roaches and termites have evolved  \n225 Modern ferns have evolved  \n225 Bees have evolved  \n200 Pangaea starts to break apart  \n200 Primitive crocodiles have evolved  \n200 Appearance of mammals  \n145 Archaeopteryx walks the Earth  \n136 Primitive kangaroos have evolved  \n100 Primitive cranes have evolved  \n90 Modern sharks have evolved  \n65 K-T Boundary--extinction of the dinosaurs and beginning of the reign of mammals  \n60 Rats, mice, and squirrels have evolved  \n60 Herons and storks have evolved  \n55 Rabbits and hares have evolved  \n50 Primitive monkeys have evolved  \n28 Koalas have evolved  \n20 Parrots and pigeons have evolved  \n20-12 The chimpanzee and hominid lines evolve  \n10-4 Ramapithecus exist  \n4 Development of hominid bipedalism  \n4-1 Australopithecus exist  \n3.5 The Australopithecus Lucy walks the Earth  \n2 Widespread use of stone tools  \n2-0.01 Most recent ice age  \n1.6-0.2 Homo erectus exist  \n1-0.5 Homo erectus tames fire  \n0.3 Geminga supernova explosion at a distance of roughly 60 pc--roughly as bright as the Moon \n0.2-0.03 Homo sapiens neanderthalensis exist  \n0.05-0 Homo sapiens sapiens exist  \n0.04-0.012 Homo sapiens sapiens enter Australia from southeastern Asia and North America from northeastern Asia  \n0.025-0.01 Most recent glaciation--an ice sheet covers much of the northern United States  \n0.02 Homo sapiens sapiens paint the Altamira Cave \n0.012 Homo sapiens sapiens have domesticated dogs in Kirkuk, Iraq  \n0.01 First permanent Homo sapiens sapiens settlements  \n0.01 Homo sapiens sapiens learn to use fire to cast copper and harden pottery  \n0.006 Writing is developed in Sumeria\n\n\nFor a Visual representation of all this go here:\nhttp://www.lpi.usra.edu/education/timeline/