# Which component in a 3-component Sp receiver function is the actual Sp RF?

In a 3-component Sp RF I have the green's function in P,SV, and SH. The actual component to the RF that shows the Sp conversion (the one always published in the literature), which would represent as a negative phase around the LAB and a big positive one over the Moho, would have to be the P component...right? I have three components to these RFs, but they were never labeled, two of them have the zero lag arrival at the same exact time while the third has its zero lag arrival occur about 3 seconds before the other two. Remember this is an Sp RF!

As an S wave in an non-isotropic (i.e. Earth) media would have some level of energy in two components, SV and SH (albeit the SH is always a lower SNR given the Earth is not actually isotropic), it completely makes sense that the two components in the receiver function that happen to have the zero lag direct arrival of the wave at the EXACT same time would have to be the SV and SH components.

Given that one of these two has a much lower SNR I could also argue which one is SV and which one is SH. Furthermore, since the only remaining component has its direct arrival occur BEFORE the other two I should naturally conclude this to be the P component! ....but this is where it gets complicated....this supposed P component does not have a clear positive spike where the Moho should be and a clear negative spike where the LAB should be.....the supposed SV component does....

I feel like I am just standing at the door before I walk in and learn an incredibly powerful lesson about the Earth, but I also feel like I want someone to walk through with me and tell me I'm on the right track in terms of my thinking....so am I??

• Hello, and welcome to Stack Exchange. Your question is phrased such that only an expert in seismology would understand it, let alone be able to answer it, which is perhaps why you only have one answer (which you'll note starts "I am not sure I clearly understand the question"). You might want to edit it to make it clearer, not the least by spelling out some of the acronyms. Commented Dec 14, 2015 at 1:51