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Recent XMM-Newton observations of the cooling flow gas in M87 indicatesharply decreasing oxygen, iron and silicon abundances within $\sim 5$ kpc ofthe galactic center. This result is unexpected since stellar mass loss and TypeIa supernovae are expected to produce pronounced central abundance maxima forall three elements. However, it has been suggested that many of the strongX-ray lines are optically thick and diffuse to larger radii in the cooling flowbefore escaping, falsifying the central abundances. We verify with radiationtransfer calculations that this effect does indeed occur in the M87 coolingflow, but that it is insufficient to account for the M87 observations. Wesuggest that some source of continuous opacity is required to reduce thecentral X-ray line emission, perhaps by warm gas at $T \sim 10^5 - 10^6$ K. Theradial surface brightness profiles of X-ray resonance lines are also sensitiveto turbulence in cooling flows which reduces the line center optical depthsconsiderably. Turbulence may provide sufficient energy to continuously heat thewarm absorbing gas.Comment: 4 pages (emulateapj5) with 2 figures; accepted by Astrophysical  Journal Letter

Spatial Diffusion of X-Ray Emission Lines in the M87 Cooling Flow; Evidence for Absorption