In geology, the K/T boundary represents the division between what and what?
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It is the division between the time periods of the Cretaceous and Tertiary ,about 65 million years ago when the main dinosaurs extinctions occurred
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What Is It?\nScientists have learned that the Earth's crust is fractured into a series of "plates" that have been moving very slowly over the Earth's surface for millions of years. Two of these moving plates meet in western California; the boundary between them is the San Andreas fault. The Pacific Plate (on the west) moves northwestward relative to the North American Plate (on the east), causing earthquakes along the fault. The San Andreas is the "master" fault of an intricate fault network that cuts through rocks of the California coastal region. The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth. In detail, the fault is a complex zone of crushed and broken rock from a few hundred feet to a mile wide. Many smaller faults branch from and join the San Andreas fault zone. Almost any road cut in the zone shows a myriad of small fractures, fault gouge (pulverized rock), and a few solid pieces of rock.
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Stratigraphic columns give the geologic history of an area. Faults & folding give a tectonic history. By examining the types of rocks that have been deposited, intruded, folded, turned over, etc. geologists have a "relative" idea (pun intended) of the workings of the earth in the past.\n\nI spend about a week teaching my 9th grade earth science students about stratigraphy. They love figuring out strat cross-sections. For them it's like doing a puzzle.
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Divergent Boundaries...\n\nContinental/Continental: rift valleys i.e. East African Rift Valley\n\nOceanic/Oceanic: new crust is being formed on the ocean floor at oceanic ridges. The Mid-Atlantic Ridge is an example. The U.S. moves about 5cm away from Europe each year b/c of this.\n\nConvergent Boundaries...\n\nContinental/Continental: Both are of the same density & both are less dense than the molten material beneath so neither will be subducted. They form folded mountain chains such as the Appalachians of the U.S. & the Alps of Europe.\n\nContinental/Oceanic: Ocean crust is much denser & will be subducted under the continental. Friction from plate movement underneath the crust will cause melt & the crust will thin causing some volcanic mountains to appear.\n\nOceanic/Oceanic: One of the oceanic crusts will be subducted & a trench will be created. Volcanic island arcs are associated w/ this type of boundary.
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mountains form when techtonic plate hit each other, sometimes one will go over the other. they can also both go up and form a mountain. if 2 techtonic plates both dig downward then u have a valley.
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Geologists state that 200 million years ago a series of 'bucklings' caused by shifting tectonic plates created the Appalachian chain of mountains, which run from Tennessee across the Canadian Border. The Catskills are a portion of this plateau which simply "refused to go along." Their bedrock refused to "buckle". Instead this bedrock rose up by easy stages from the shallow sea in which its rocks (sedimentary?) had been formed (deposited?) from ancient mountains to the east. Raised high in the air the plateau became easy prey to the cutting action of the streams which carried off the plateau's rainwater. The plateau was carved up over 100's of thousands of years...the tough, hardest parts remained while the softer material was disposed of by various erosion techniques and actions including frost, water action and wind. Geologists explain the Catskills are simply a tough part of the Allegheny Plateau which the streams, even with the help of frost and gravity have not yet cut down to size. Over vast geologic time, of course, these forces will do away with the whole thing. In the meantime, scientifically speaking, the Catskills should be described as 'a maturely dissected part of the Allegheny Plateau".
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mohorovicic is a "discontinuity zone" as the scientists name it.that means it's a zone "inside" Earth where the matter(materia) changes it's properties.there are more "discontinuity zones"inside the Earth .In mohorovicic's case, the matter(materia) is changing from solid(Earth's crust)to  liquid-the astenosphere(upper layer of the mantle where the temperatures are lower than in the rest of the mantle and the density of matter is smaller<the liquid is more"liquid" than in the rest>) containing the magma
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There is no boundary as such because there is "nothing" beyond the edge; but the Universe in not infinite.  Difficult to get your head around I know especially as "nothing" in this case does not mean nothing as you understand it now.  If I go on you might blow a fuse so I will stop there.\n\n[re: above - "The Milky Way" is the name of our Galaxy not our Solar system]
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An unconformity is a gap in time in rock layers, where erosion occurs while deposition slows or stops. The rocks above an unconformity are younger than the rocks beneath (unless the sequence has been overturned). An unconformity represents time during which no sediments were deposited and the local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area. The interval of geologic time not represented is called a hiatus. There are three types of unconformities: disconformity, nonconformity, and angular unconformity.\n\nDisconformity\nAn unconformity between parallel layers of sedimentary rocks which represents a period of erosion or non-deposition.\n\nNonconformity\nAn unconformity exists between sedimentary rocks and metamorphic or igneous rocks when the sedimentary rock lies above and was deposited on the pre-existing and eroded metamorphic or igneous rock.\n\nAngular Unconformity\nAn unconformity where horizontally parallel strata of sedimentary rock is deposited on tilted and eroded layers that may be either vertical or at an angle to the overlying horizontal layers. The whole sequence may later be deformed and tilted by further orogenic activity.\n\nRetrieved from "http://en.wikipedia.org/wiki/Unconformity"
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Tectonics, (from the Greek for "builder", tekton), is a field of study within geology concerned generally with the structures within the crust of the Earth (or other planets) and particularly with the forces and movements that have operated in a region to create these structures.
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A, because it's the division between two tectonic plates. the plates move apart and magma from inside the earth comes up and piles up in the form of mountains.
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According to Wikipedia:\n\n| The trench is the boundary where two tectonic \n| plates meet, a subduction zone where the Pacific \n| Plate is being subducted under the Philippine Plate.\n\nThe force of the one Pacific plate pushing/pulling under the other plate is causing the rift.
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Igneous, they tell us a lot about what the age of the Earth and location of the poles.\n\nSedimentary, tell us the climate of an area and preserve fossils.\n\nMetamorphic, they look cool but are hard to tell anything from.  Their general location tells us of orogenies and faults.\n\nAll rocks are important and different geologists study different things.  Oil bearing shale is important to some geologist since if we can figure out an economical method of extraction we wouldn't be dependent on other countries for oil.\n\nGeology is like a big puzzle, and it's interesting seeing how the pieces fit together.
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The geometric orientation of any planar geological feature (e.g., bedding planes, joints, or faults) is described in terms of the feature's strike and dip.  The strike is the compass direction of the line formed by the intersection of the planar feature with the Earth's surface, and the dip is the angle that the plane makes with respect to the surface.  \n\nIf you are making measurements in the field, one uses a compass and "clinometer" (a device that measures angles) to determine the strike and dip, respectively.  (by taking a compass bearing and measuring the dip angle).\n\nIf you are looking at a geologic map and trying to determine the strinke and dip of a feature, then this is indicated on the map by a special symbol that looks like a short line with another, shorter line on one side of the line at right angles to the first (i.e., a "tick mark").  There will be a number next to the shorter line.  The strike direction is given by the orientation of the longer line, and the dip direction by the shorter "tick mark".  The dip angle is given by the number next to the short "tick mark".\n\nSee sources.
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Is this a question?  I was confused by the lack of a complete sentince.  \n\nHowever, if the strata are flat, there is no special name for it.  It's just a bedding layer.  It's measured by the strike (horizontal direction) and the dip (amount it's sloping down).  If it folds and the youngest material is on the inside, it's a syncline (v shaped), but if the youngest material is on the outside, it's an anticline (A shaped)  Then, if the fold is not level, it's called a plunging anticline/syncline.
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(m)\n\nUsed in geology,building science and hydrogeology, the porosity of a rock or sediment is the proportion of the non-solid volume to the total volume of material, and is defined by the ratio: where Vp is the non-solid volume (pores and liquid) and Vm is the total volume of material, including the solid and non-solid parts. Both and are used to denote porosity.
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A layer of seperation between "things".