| Abstract: | We present stacked record sections of Global Seismic Network data that image the average amplitude and polarization of the high-frequency Pdiff coda and investigate their implications on the depth extent of fine-scale (~10 km) mantle heterogeneity. The extended 1-Hz coda lasts for at least 150 sec and is observed to a distance of 130??. The coda‘s polarization angle is about the same as the main Pdiff arrival (4.4 sec/deg) and is nearly constant with time. Previous studies show that multiple scattering from heterogeneity restricted to the lowermost mantle generates an extended Pdiff coda with a constant polarization. Here we present an alternative model that satisfies our Pdiff observations. The model consists of single scattering from weak (~1%) fine-scale (~2 km) structures distributed throughout the mantle. Although this model is nonunique, it demonstrates that Pdiff coda observations do not preclude the existence of scattering contributions from the entire mantle. |
| Genre: | Article |
| ProdID: | 70023499 |
| Citation Author: | Earle, P. S.; Shearer, P. M. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 1881 |
| Citation Issue: | 6 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Bulletin of the Seismological Society of America |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 7 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda; 2001; Article; Journal; Bulletin of the Seismological Society of America; Earle, P. S.; Shearer, P. M. |
| Citation Start Page: | 1875 |
| Citation Volume: | 91 |
| Citation Year: | 2001 |
| Type: | citation/reference |
| Text: | Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda; 2001; Article; Journal; Bulletin of the Seismological Society of America; Earle, P. S.; Shearer, P. M. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.1785/0120000285 |
| Date Other: | Mon, 1 Jan 2001 00:00 -0600 |
| Publisher: | |
