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While the receiver function technique has been successfully applied to high‐resolution imaging of sharp discontinuities within and across the lithosphere, it suffers from severe limitations when applied to seafloor seismic recordings. This is because the water and sediment layer could strongly influence the receiver function traces, making detection and interpretation of crust and mantle layering difficult. This effect is often referred to as the singing phenomena in marine environments. We demonstrate, using analytical and synthetic modeling, that this singing effect can be reversed using a selective dereverberation filter tuned to match the elastic property of each layer. We apply the dereverberation filter to high‐quality earthquake records collected from the NoMelt seismic array deployed on normal, mature Pacific seafloor. An appropriate filter designed using the elastic properties of the underlying sediments, obtained from prior studies, greatly improves the detection of Ps conversions from the Moho (∼8.6 km) and from a sharp discontinuity (<∼5 km) across the lithosphere asthenosphere transition (∼72 km). Sensitivity tests show that the dereverberation filter is mostly sensitive to the two‐way travel time of the shear wave in sediment and is robust to seismic noise and small errors in the sediment properties. Our analysis suggests that selectively filtering out the sediment reverberations from ocean seismic data could make inferences on subsurface structure more robust. We expect that this study will enable high‐resolution receiver function imaging of the oceanic plate across the growing ocean bottom seismic arrays being deployed in the global oceans. Key Points: A dereverberation filter is proposed to eliminate the sediment reverberation effects on receiver functions of ocean bottom seismological dataThe proposed filter is proven effective and robust to small errors in sediment properties using synthetic modelingA Moho of 8.6 km depth and a sharp discontinuity of the lithosphere asthenosphere transition of 72 km depth is observed [ABSTRACT FROM AUTHOR]

The stable continents have a puzzling structure. Recent seismological studies have revealed a marked drop in seismic velocity at middle-lithosphere depths, but a generally small velocity drop at the lithosphere-asthenosphere boundary. The mid-lithosphere discontinuity has previously been attributed to changes in composition and/or crystal alignment (anisotropy) caused by metasomatic alteration, as well as to partial melting and/or accretion of intruded materials that occurred after the formation of the continents. We show that these models cannot easily explain the global presence of a large seismic velocity drop in the middle lithosphere and a small velocity change at the lithosphere-asthenosphere boundary. These models are also difficult to reconcile with long-term continental stability and, in particular, observations of nearly depth-invariant ages of rocks in the continental lithosphere that do not support the notion of late alteration events. Instead, we propose an elastically accommodated grain-boundary sliding model that predicts a substantial velocity drop at the mid-lithosphere discontinuity and a weak seismic signal at the lithosphere-asthenosphere boundary, as observed, without invoking late-stage modifications to the lithosphere. In this model, the mid-lithosphere discontinuity is a general feature of the stable continents, the precise depth of which depends primarily on temperature and water content. Consequently, the depth of the mid-lithosphere discontinuity may provide clues to the evolution of continents. [ABSTRACT FROM AUTHOR]

Seismic imaging with converted body waves has been used to infer layering within the globallithosphere leading to observations of a globally ubiquitous boundary known as themid-Lithosphere discontinuity (MLD). Explanatory models include partial melt/chemicalstratification, anisotropy, and elastically-accommodated grain-boundary sliding; each withunique implications for the geological evolution of continents. We present a new method forinvestigating these hypotheses, using a parametric approach which involves stacking ofthree-component earthquake-source deconvolved- receiver function traces.We conduct a statistical parameter search to determine the lithospheric discontinuity depth(H), the wave-speed ratio (κ), and order,φ, of harmonic back-azimuth variations, whichcan distinguish conversions from sub-crustal layers with anisotropic media. We demonstratethe procedure with a pilot study of synthetic waveforms and long-running seismic stationslocated in the Precambrian region of the US. We target sub-crustal depths, and distinguishbetween free surface reverberations, using a suite of high-resolution crustal 1D (PREM,IASP91, AK135) and 3D models (Crust1.0, LITHO1.0, and EMC-US.2016) velocity models.The results have important implications for the origin of the MLD and the approach can beused to study other cratonic regions globally. [ABSTRACT FROM AUTHOR]