Recent content by AlecYates

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    Amplitude decrease with geometrical spreading

    Hey, I'm looking at amplitude decrease of a seismic pulse as a result of geometrical spreading. Starting with I = E / (4 * pi * r2) where E = original energy from source, we know that energy falls off as 1/r2, thus amplitude falls off as 1/r. From wikipedia: "The energy or intensity...
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    Absorption of energy in a seismic pulse

    "Not sure of your level of knowledge in seismology" low I imagine, it's only been a recent attempt at moving beyond a surface level knowledge of seismology in an attempt to pursue a career in it. Currently doing some pre-study before beginning a graduate course in geophysics. checked up on...
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    Absorption of energy in a seismic pulse

    Hey, Just doing some reading on this and I'm a little confused as to why absorption produces a progressive lengthening of a seismic pulse. Quote from the textbook "In general, the effect of absorption is to produce a progressive lengthening of the seismic pulse". I understand how the...
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    What is the ratio of wave amplitudes at two sites with 5dB attenuation?

    Okay sweet, so this is where I'm at (there are no solutions provided unfortunately). The change in dB between site A and site B is 5dB. A change in power ratio by a factor of 10 corresponds to a change of 10dB. Therefore the power ratio would be 10^(5/10) = 3.16 (2.d.p) since P = A^2 the...
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    What is the ratio of wave amplitudes at two sites with 5dB attenuation?

    Homework Statement Doing my own independent study, and I've come across a textbook question I'm rather lost on. Problem: Over the distance between two seismic recording sites at different ranges from a seismic source, seismic waves have been attenuated by 5dB. What is the ratio of the wave...
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    How Do You Resolve Negative Indices in Convolution Calculations?

    "Now as an exercise, make sense of that with the i and k indexes and your original formula to make sure you understand what the formula is saying." Awesome feedback. It's actually the 'exercise' I was having the most issue with, though I appreciate the strong explanation of the method of...
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    How can I obtain the convolution output for an input function and operator?

    Yup seems to be. Guess I'll assume it an error within the text and move on. Cheers
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    How can I obtain the convolution output for an input function and operator?

    Yeah they have a demonstration of this on the next page of the textbook, which is easy enough to follow (although it didn't mention anything about the reversed filter which is helpful, I had wondered if it was a mistake originally). It's just frustrating I can't get the same result using the...
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    How Do You Resolve Negative Indices in Convolution Calculations?

    Hey, I've begun going through a book called "An introduction to geophysical exploration" by Phillip Kearey and Michael Brooks and I've come across a problem I can't for the life of me see how they got their answer. Essentially, given an input function gi (i = 1,2... m), and a convolution...
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    How can I obtain the convolution output for an input function and operator?

    Just realized this should be in the homework/CW area (by the rules listed in the pinned thread). Reposting.
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    How can I obtain the convolution output for an input function and operator?

    Hey, I've begun going through a book called "An introduction to geophysical exploration" by Phillip Kearey and Michael Brooks and I've come across a problem I can't for the life of me see how they got their answer. Essentially, given an input function gi (i = 1,2... m), and a convolution...
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