How is seismic tomography used in the exploration of kimberlite pipes?
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The first thing to understand is that no geophysical method can tell what  rock exist in the subsurface. The geophysical methods are basically the response of the rocks to some invading signal or  measurements of some physics-chemical attributes. This information or data is correlated with the known geological information of the area.\n Now ur question to know kimberlites through seismic methods - due to density contrast and disposition of kimberlites the seismic waves response would indicate an anomaly. Now if the kimberlite pipe is not exposed or does not have a show, it would be difficult to come to a definite conclusion about the presence of kimberlite pipe. The imp. query would be what is the country or enveloping rock of the kimberlite pie and what is its depth? But an experienced geophysicist  with available geological information can at least say that a pipe like feature is expected. Normally for such targets a single method is seldom useful, multiple methods are normally employed in exploration to arrive at a definite interpretation. Gravity method could be very useful for kimberlite pipes in areas with density contrast.
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simply go search for crustal earhquakes,it's that easy.The search bar can pull up anything imaginable.
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well i really don't recall the actuall machine that does it, but basically you need to make a 3d map of the underground arround your house. Using a hyped version of an ultrasound there is a machine that lets you "see" the underground by interpretting the density of the object below so an object thats more dense than the ground (a wall of a secret room, a skull, a bag of golden coins) would be spottable
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Seismic waves from earthquakes behave differently in different mediums.  Using data from seismometers (devices that measure earthquake energy) around the world, you can study the seismic waves generated from major earthquakes.  The types of waves, and their travel times tell geophysicists a lot of information about the interior of the earth.  The most recent development in this science is called Mantle Tomography - they can even resolve the presence of cold subducting plates!
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The deepest research borehole ever drilled was in Russia, on the Kola peninsula. Over a period of more than a decade a huge purpose-built rig drilled to over 12 kilometres to investigate the structure of the Continental Crust (sorry about the units, I'm in Australia and we're metric here - so are the Russians). \n\nThe results showed unexpected fractures and fissures and water-bearing zones deep in the crust, where conventional wisdom expected the pressure of rock above to close up all cracks. \n\nThe deepest oil wells that I know are drilled to about 6km, say 20,000ft. Most normal oil wells are drilled to about 3000 to 5000 metres -10,000 to 16,000 ft.
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P Waves are compressional waves that vibrate in the same direction as they are traveling, and travel about 5000 meters/second (16,000 feet/second).  S-waves are shear waves which vibrate perpendicular to the direction they are traveling, and move only about 58% as fast as the P waves. The difference in arrival times of the two waves can be used to determine the distance they have traveled from the epicenter. By using two or more seismic stations the direction of travel can be determined and the epicenter pinpointed.
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P Waves are compressional waves that vibrate in the same direction as they are traveling, and travel ABOUT 5000 meters/second (16,000 feet/second). S-waves are shear waves which vibrate perpendicular to the direction they are traveling, and move only about 58% as fast as the P waves. The difference in arrival times of the two waves can be used to determine the distance they have traveled from the epicenter. By using two or more seismic stations the direction of travel can be determined and the epicenter pinpointed. \n\nOf course there are many variables that affect the velocity of seismic waves. Seismic velocity increases with increasing density, so variations in lithology, pore fluid (gas, oil, water), depth, temperature, and distance of travel (especially over global distances) all require modeling in order to process the data and image both time and depth properly. Examples of these types of problems are seismic waves that travel through the deep mantle from earthquakes. Because the distance, temperature, and density all have variations, this requires compensation. Seismic data acquired by the oil industry over ocean floor deposits which contain layers of salt requires that the salt be modeled in order to compensate for the different density of the salt from surrounding rock. For many years it was almost impossible to image under salt, but with improved technology it is now done routinely in 3 dimensions. All of this processing is aimed at obtaining accurate time and depth images of the subsurface.
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To characterize and identify electrofacies groups, we perform a multivariate analysis of the well-log data using PCA, MCA, and discriminant analysis.8,9,12-16 Such electrofacies classification does not require any artificial subdivision of the data population: it follows naturally based on the unique characteristics of welllog measurements reflecting minerals and lithofacies within the logged interval.
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There are several other mnemonics for these types of logs, depending on the company who is logging the well. These include FMI and FMS (Schlumberger), EMI (Halliburton), HMI, OBMI (Schlumberger), STAR (Baker Atlas), CAST, UBI (Shlumberger),FMS, EarthImager (Baker Atlas), and FAC-40. They are generically referred to as electrical borehole images and are essentially sophisticated dipmeter logs. It is a map of the shallow resistivity. Both UBI and OBMI are Schlumberger logs for application in oil-base mud. Schlumberger’s product brochure is here (link to pdf):\n\nhttp://www.slb.com/media/services/evaluation/geology/obmi.pdf\n\nA good introduction is in “Basic Well Log Analysis” by George Asquith and Daniel Krygowski published by AAPG. ISBN 0891816674  If you can’t find this in your library you can get it from AAPG directly (the link is below) and by joining AAPG can get a discount on books. \n\nIn my experience using these logs I have found them incredibly useful for detailed facies analysis, yielding detailed information such as paleoflow direction. Baker Atlas in Houston has a team that is dedicated to this type of depositional analysis. Another excellent application for these logs is in fracture analysis. It is possible to determine frequency and orientation of macro-fractures and use them for directional drilling or other applications such as reservoir evaluation. My experience with oil-based mud image logs has been that they are not as good as water-based logs, however, when oil-base mud is needed, the quality of the image log is not likely to be a priority. Another difficulty you will encounter researching these logs is that they are almost never in the public domain. Unlike common logs such as Gamma Ray and Resistivity, these logs are not required to be turned over to the state (in the US) so they remain locked up in oil company libraries and are not shared with the common suppliers of well logs such as A2D and IHS Energy. In some countries this may be different, but because these logs are expensive to produce they have not been used in many places.   \n\nTo find detailed information I suggest using GeoRef. Most university libraries have access. \nhttp://www.agiweb.org/georef/\nOther resources were you will find information on these logs will be the Society of Petroleum Engineers:\nhttp://www.spe.org/\nSWPLA (Society of Professional Well Log Analysts):\nhttp://www.spwla.org/\nAAPG (American Association of Petroleum Geologists):\nhttp://www.aapg.org/\nA2D is at:\nhttp://www.a2d.com/\nIHS Energy is at:\nhttp://energy.ihs.com/\n\n\nOne resource I found:\nhttp://www.spe.org/elibinfo/eLibrary_Papers/spe/2004/04ADIPEC/00088688/00088688.htm
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Try this website for information on transverse and longitudinal waves:\n\nhttp://www.kettering.edu/~drussell/Demos/waves/wavemotion.html
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Go the web-page below, u will almost all the details:-\n\nhttp://en.wikipedia.org/wiki/Seismic_retrofit
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You should read the following papers published by Gus Archie who worked for Shell Oil Company. Archie was credited with coining the term petrophysics. \n\nHis papers that describe the empirical relationship between resistivity and porosity:\n\nThis is the key paper by Archie:\n\nArchie, G.E., 1942, The electrical resistivity log as an aid in determining some reservoir characteristics, Journal of Petroleum Technology, V 5, pp 54-62    (you may find this as Transactions of American Institution of Mining, Metallugical, and Petroleum Engineers or just as Trans. AIME. )\n\nOthers:\nArchie, G.E., 1947, Electrical Resistivity an aid in Core-Analysis Interpretation, Bulletin of the American Association of Petroleum Geologists, Vol 31, No 2, pp 350-366\n********************************************\nHis paper that describes the relationships between pore distribution and porosity/permeability, and fluid distribution:\n\nG.E. Archie, 1950, Introduction to Petrophysics of Reservoir Rocks, Bulletin of the American Association of Petroleum Geologists, Vol 34, No 5, pp 943-961\n\n***********************************\nArchie's paper for carbonates was the first attempt to relate rock fabrics to petrophysical properties in carbonates, which is of limited usefulness today. If you are specifically interested in carbonates I would recommend reading the book "Carbonate Reservoir Characterization" by F. Jerry Lucia, 1999, that describes the Lucia transform methods for carbonates, or read some of Lucia's other publications.\n\nG.E.Archie, 1952, Classification of Carbonate Reservoir Rocks and Petrophysical Considerations, Bulletin of the American Association of Petroleum Geologists, Vol 36, No 2, pp 278-298\n**********************************************\n\nArchie's work can be summarized in the following relationship:\n\nR sample ~ Ro = F Rw\n\nR is resistivity, F is formation factor\n\nArchie eventually admited that a relationship between formation factor and permeability did not exist, but one did seem to exist for porosity. It can be expressed as a power law of the form:\n F ~ 1/phi^m \n\n(m is the cementation exponent)\n\nUnder conditions of constant saturation, the lower the porosity, the higher the apparent resistivity will be. \n\nHere is a list of key petrophysical papers:\nhttp://www.petrophysics.net/papers.htm\n\nThe AAPG Bulletin papers can be downloaded from \nhttp://www.aapg.org/ if you are a member. If not, most university libraries carry this publication. A major university library should have the Journal of Petroleum Technology paper as well.
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look up plate tectonics
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for starters\n\n0) Digging/going down mines, though that doesn't get very far!!!\n\n1) Seismic waves from earthquakes - they spread through the Earth and are picked up by seismographs all over the world - there are 2 types that travel through, p-waves and s-waves, but the 2 types are not picked up all over; s-waves don't travel through liquids.\n\n2) Lab investigations of the materials that are likely to be within the earth, under appropriately high temperatures and pressures\n\nPutting the results of these together has built up a model of a thin crust, mantle, liquid outer core and solid inner core.\n\nYou may want to search for terms like:\nseismology, body wave, shadow zone, p-wave (promary wave), s-wave (secondary wave)
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It is a complex process, so I will try to hit on the most important factors. \n\nIn past years oil exploration was done based on the observation of oil seeps at the surface. In many areas oil seeps out of the ground naturally, so these were likely places to drill. As geologic understanding grew, geologists realized that certain structures were likely to contain oil. The first geologist going into Saudi Arabia identified drilling sites from the deck of the ship before he even landed. He could see the structures that were likely to contain oil. As the easy finds have been drilled, the process has gotten much more scientifically rigorous. \n\nOften oil exploration starts with an exercise called basin modeling. Geologists look at ancient basins and use available evidence to determine \n1) if there is adequate source rock of sufficient organic content and of the proper organic content to generate oil\n2) if the burial and subsidence history of the basin was such that at some time in the past the source rock was forced to a depth where the temperature and pressure were ideal for petroleum generation \n3) the oil expelled from the source rock had a migration path that allowed it to escape from the source rock\n4) there were traps created by structure (anticlines, synclines, fault blocks, etc) or stratigraphy (variations in rock composition) that existed at the same time as the migration took place \n5) there was a seal on the trap that prevented escape of the oil or gas over the long period of time that the oil resided there\n6) the past heat gradient of the basin was such that the temperature of the source rock reached the ideal temperature range and did not get too hot or stay too cold. \n\nAs you can guess, a good understanding of a basin's geologic history is necessary, including it's deposition, burial, subsidence, uplift, and faulting history. Misunderstanding or incomplete evidence of any one of these factors results in more risk of failure. \n\nThe efficiency of the kitchen (the area where the organic material in the source rock is being 'cooked' into oil) can be evaluated with several different kinds of data. Certain organic compounds known as vitrinite can be examined and can give visual evidence of the maximum temperature they have reached. These samples are taken from well cuttings so the approximate depth of the sample is known. Bottom hole temperatures of existing wells are commonly measured and plotted on maps, as well as the temperature gradient coming up through the well. Apatite fission track analysis is another method for determining the thermal history of a sample and can tell the story of the burial history. \n\nIf there is adequate organic material of the proper makeup and if it can be predicted that it reached a temperature of more than 140 degrees F, then it was likely to generate oil. While it was between 140 F and 320 F it would have been generating oil, and beyond about 200 F, it would have started generating natural gas. If it stayed in the high end of that range long enough, the oil would have changed to natural gas. Beyond about 390 F both oil and natural gas will break down and change to graphite. Understanding this thermal history will lead to predictions about the existence and the potential quantity of oil and gas in a basin. \n\nPressure is also a factor in this process. When the hydrostatic or lithostatic pressure reaches a certain point, oil will begin cracking to form natural gas. Quite often this change can generate what is called overpressure in the reservoir, where the reservoir pressure actually is higher than lithostatic pressure and it can be dangerous for drilling if not anticipated.\n\nOne of the most fascinating parts of this basin modeling process is that different oil reservoirs can be identified by a geochemical signature that can be traced back to the original source rock. Often when working in a basin there is more than one source rock, and more than one possible mig
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http://www.hydrocarbons-technology.com/projects/snohvit/snohvit1.html
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3 dim seismic vibrations