Deep mantle seismic modeling and imaging

Annual Review of Earth and Planetary Sciences

Volumn 39, Issue , 2011, Pages 91-123

  Lay, Thorne ^a   Garnero, Edward J ^b  

^a UNIVERSITY OF CALIFORNIA   (United States)

^b ARIZONA STATE UNIVERSITY   (United States)

Author keywords

core mantle boundary; D ; lower mantle structure; superplumes; thermochemical anomalies; ultralow velocity zones

Indexed keywords

CORE-MANTLE BOUNDARY; LOWER-MANTLE STRUCTURE; SUPERPLUMES; THERMOCHEMICAL ANOMALIES; ULTRALOW VELOCITY ZONE;

ARRAY PROCESSING; PHASE EQUILIBRIA; SEISMIC WAVES; THREE DIMENSIONAL; TOMOGRAPHY; TRANSPORT PROPERTIES; VELOCITY CONTROL;

SEISMOLOGY;

ARRAY; CORE-MANTLE BOUNDARY; GEOPHYSICS; HEAT FLOW; IMAGE ANALYSIS; NUMERICAL MODEL; RESOLUTION; SEISMIC WAVE; SEISMOGRAM; THREE-DIMENSIONAL MODELING; TOMOGRAPHY; VELOCITY;

CALLUNA VULGARIS;

EID: 79955510265     PISSN: 00846597     EISSN: None     Source Type: Book Series    
DOI: 10.1146/annurev-earth-040610-133354     Document Type: Article

References (181)

1. Ammann MW, Brodholt JP, Wookey J, Dobson DP. 2010. First-principles constraints on diffusion in lower-mantle minerals and a weak D" layer. Nature 465:462-65
2. Antolik M, Gu YJ, Ekstrom G. 2003. J362D28: anew joint model of compressional and shear velocity in the Earth's mantle. Geophys.J. Int. 153:443-66 (Pubitemid 36632372)
3. Avants M, Lay T, Garnero EJ. 2006a. A new probe of ULVZ S-wave velocity structure: array stacking of ScS waveforms. Geophys. Res. Lett. 33:L07314
4. Avants M, Lay T, Russell SA, Garnero EJ. 2006b. Shear velocity variation within the D" region beneath the Central Pacific. J. Geophys. Res. 111:B05305
5. Bilek SL, Lay T. 1998. Lower mantle heterogeneity beneath Eurasia imaged by parametric migration of shear waves. Phys. Earth Planet. Inter. 108:201-18 (Pubitemid 28556159)
6. Brana L, Helffrich G 2004. A scattering region near the core-mantle boundary under the North Atlantic. Geophys. J. Int. 158:625-636 (Pubitemid 39131194)
7. Breger L, Romanowicz B, Ng C. 2001. The Pacific plume as seen by S, ScS, and SKS. Geophys. Res. Lett. 28:1859-62 (Pubitemid 32575933)
8. Buffett BA, Garnero EJ, Jeanloz R. 2000. Sediments at the top of Earth's core. Science 290:1338-42
9. BullenKE. 1949. Compressibility-pressure hypothesis and the Earth's interior. MNRAS Geophys. Suppl. 5:355-68
10. Burke K. Steinberger B, Torsvik TH, Smethurst MA. 2008. Plume generation zones at the margins of large low shear velocity provinces on the core-mantle boundary. Earth Planet. Sci. Lett. 265:49-60 (Pubitemid 350227236)
11. Burke K, Torsvik TH. 2004. Derivation of large igneous provinces of the past 200 million years from long-term heterogeneities in the deep mantle. Earth Planet. Sci. Lett. 227:531-38 (Pubitemid 39428200)
12. Cao A, Romanowicz B. 2007. Locating scatterers in the mantle using array analysis of PKP precursors from an earthquake doublet. Earth Planet. Sci. Lett. 255:22-31
13. Castle JC, Creager KC, Winchester JP, van der Hilst RD. 2000. Shear wave speeds at the base of the mantle. J. Geophys. Res. 105:21543-57
14. Castle JC, van der Hilst RD. 2000. The core-mantle boundary under the Gulf of Alaska: no ULVZ for shear waves. Earth Planet. Sci. Lett. 176:311-21 (Pubitemid 30234125)
15. Castle JC, van der Hilst RD. 2003. Using ScP precursors to search for mantle structures beneath 1800 km depth. Geophys. Res. Lett. 30(8):1422
16. Catalli K, Shim S-H, Prakapenka V. 2009. Thickness and Clapeyron slope of the postperovskite boundary. Nature 462:782-785
17. Chaloner J, Thomas C, Rietbrock A. 2009. P-and S-wave reflectors in D" beneath South-East Asia. Geophys. J. Int. 179:1080-92
18. Chambers K, Woodhouse JH. 2006a. Investigating the lowermost mantle using migrations of long-period S-ScS data. Geophys. J. Int. 166:667-78 (Pubitemid 44082256)
19. Chambers K, Woodhouse JH 2006b. Transient D" discontinuity revealed by seismic migration. Geophys. Res. Lett. 33:L17312.
20. Cormier VF. 1999. Anisotropy of heterogeneity scale lengths in the lower mantle from PKIKP precursors. Geophys.J. Int. 136:373-84 (Pubitemid 29199212)
21. Cormier VF. 2000. D" as a transition in the heterogeneity spectrum of the lowermost mantle. J. Geophys. Res. 105:16193-205
22. Deschamps F, Trampert J. 2003. Mantle tomography and its relation to temperature and composition. Phys. Earth Planet. Inter. 140:272-91
23. Dziewonski AM, Anderson DL. 1981. Preliminary reference Earth model. Phys. Earth Planet. Inter. 25:297-356
24. Fisher JL, Wysession ME, Fischer KM. 2003. Small-scale lateral variations in D" attenuation and velocity structure. Geophys. Res. Lett. 30(8):1435
25. Flores C, Lay T. 2005. The trouble with seeing double. Geophys. Res. Lett. 32:L24305
26. Ford SR, Garnero EJ, McNamara AK. 2006. A strong lateral shear velocity gradient and anisotropy heterogeneity in the lowermost mantle beneath the southern Pacific. J. Geophys. Res. 111:B03306
27. Forte AM, Mitrovica JX. 2001. Deep-mantle high-viscosity flow and thermochemical structure inferred from seismic and geodynamic data. Nature 410:1049-56 (Pubitemid 32391031)
28. Freybourger M, Chevrot S, Kruger F, Achauer U. 2001. A waveform migration for the investigation of P wave structure at the top of D" beneath northern Siberia. J. Geophys. Res. 106:4129-40
29. Gaherty JB, Lay T. 1992. Investigation of laterally heterogeneous shear velocity structure in D" beneath Eurasia. J. Geophys. Res. 97:417-35
30. Garnero EJ. 2000. Heterogeneity of the lowermost mantle. Annu. Rev. Earth Planet. Sci. 28:509-37
31. Garnero EJ, Jeanloz R. 2000. Fuzzy patches on the Earth's core-mantle boundary. Geophys. Res. Lett. 27:2777-80 (Pubitemid 32040261)
32. Garnero EJ, Lay T. 2003. D" shear velocity heterogeneity, anisotropy and discontinuity structure beneath the Caribbean and Central America. Phys. Earth Planet. Inter. 140:219-42 (Pubitemid 37507105)
33. Garnero EJ, Lay T, McNamara AK. 2007a. Implications of lower-mantle structural heterogeneity for existence and nature of whole-mantle plumes. Geol. Soc. Am. Spec. Pap. 430:79-91
34. Garnero EJ, McNamara AK. 2008. Structure and dynamics of Earth's lower mantle. Science 320:626-28 (Pubitemid 351928337)
35. Garnero EJ, Thorne MS, McNamara A, Rost S. 2007b. Fine-scale ultra-low velocity zone layering at the core-mantle boundary and superplumes. In Superplumes: Beyond Plate Tectonics, ed. DA Yuen, S Maruyama, SI Karato, BF Windley, pp. 139-58. New York: Springer
36. Garnero EJ, Vidale JE. 1999. ScP; a probe of ultralow velocity zones at the base of the mantle. Geophys. Res. Lett. 26:377-80 (Pubitemid 29321824)
37. Glatzmaier GA, Coe RS, Hongre L, Roberts PH. 1999. The role of the Earth's mantle in controlling the frequency of geomagnetic reversals. Nature 401:885-90
38. Grand SP. 2002. Mantle shear-wave tomography and the fate of subducted slabs. Philos. Trans. R. Soc. A 360:2475-91
39. Gu YJ, Dziewonski AM, Su W, Ekstrom G 2001. Models of the mantle shear velocity and discontinuities in the pattern of lateral heterogeneities. J. Geophys. Res. 106:11169-99
40. Havens E, Revenaugh J. 2001. A broadband seismic study of the lowermost mantle beneath Mexico: constraints on ultralow velocity zone elasticity and density. J. Geophys. Res. 106:30809-20
41. He Y, Wen L. 2009. Structural features and shear-velocity structure of the "Pacific Anomaly."J. Geophys. Res. 114:B02309
42. He Y, Wen L, Zheng T. 2006. Geographic boundary and shear wave velocity structure of the "Pacific anomaly" near the core-mantle boundary beneath western Pacific. Earth Planet. Sci. Lett. 244:302-14
43. Hedlin MAH, Shearer PM. 2000. An analysis of large-scale variations in small-scale mantle heterogeneity using Global Seismographic Network recordings of precursors to PKP.J. Geophys. Res. 105:13655-73
44. Helmberger DV, Lay T, Ni S, Gurnis M. 2005. Deep mantle structure and the postperovskite phase transition. Proc. Natl. Acad. Sci. USA 102(48):17257-63 (Pubitemid 41740854)
45. Helmberger DV, Ni S. 2005. Approximate 3D body-wave synthetics for tomographic models. Bull. Seismol. Soc. Am. 9:212-24 (Pubitemid 40621483)
46. Helmberger DV, Ni S, Wen L, RitsemaJ. 2000. Seismic evidence for ultralow velocity zones beneath Africa and eastern Atlantic. J. Geophys. Res. 105:23865-78
47. Helmberger DV, Wen L, Ding X. 1998. Seismic evidence that the source of the Iceland hotspot lies at the core-mantle boundary. Nature 396:251-55 (Pubitemid 28541386)
48. Hernlund JW, Thomas C, Tackley PJ. 2005. A doubling of the postperovskite phase boundary and structure of the Earth's lowermost mantle. Nature 434:882-86 (Pubitemid 40558998)
49. Hung SH, Garnero EJ, Chiao LY, Kuo BY, LayT. 2005. Finite-frequency tomography of D" shear velocity heterogeneity beneath the Caribbean. J. Geophys. Res. 110:B07305
50. Hutko A, Lay T, Garnero EJ, Revenaugh JS. 2006. Seismic detection of folded, subducted lithosphere at the core-mantle boundary. Nature 441:333-36 (Pubitemid 44050195)
51. Hutko AR, Lay T, Revenaugh J. 2009. Localized double-array stacking analysis of PcP: D" and ULVZ structure beneath the Cocos plate, Mexico, central Pacific, and north Pacific. Phys. Earth Planet. Inter. 173:60-74
52. Hutko A, Lay T, Revenaugh J, Garnero EJ. 2008. Anticorrelated seismic velocity anomalies from postper-ovskite in the lowermost mantle. Science 320:1070-74 (Pubitemid 351929547)
53. Idehara K, Yamada A, Zhao D. 2007. Seismological constraints on the ultralow velocity zones in the lowermost mantle from core-reflected waves. Phys. Earth Planet. Inter. 165:25-46 (Pubitemid 350002259)
54. Iitaka T, Hirose K, Kawamura K, Murakami M. 2004. The elasticity of the MgSiO3 postperovskite phase in the Earth's lowermost mantle. Nature 430:442-44
55. Ishii M, Tromp J. 1999. Normal-mode and free-air gravity constraints on lateral variations in velocity and density of Earth's mantle. Science 285:1231-36 (Pubitemid 29398603)
56. Ishii M, Tromp J. 2001. Even-degree lateral variations in the Earth's mantle constrained by free oscillations and the free-air gravity anomaly. Geophys.J. Int. 145:77-96 (Pubitemid 32282081)
57. Kaneshima S, Helffrich G. 1998. Detection of lower mantle scatterers northeast of the Mariana subduction zone using short-period array data.J. Geophys. Res. 103:4825-38
58. Kaneshima S, Helffrich G. 2009. Lower mantle scattering profiles and fabric below Pacific subduction zones. Earth Planet. Sci. Lett. 282:234-39
59. Kawai K, Geller RJ. 2010. Waveform inversion for localized seismic structure and an application to D" structure beneath the Pacific. J. Geophys. Res. 115:B01305
60. Kawai K, Geller RJ, Fuji N. 2007a. D" beneath the Arctic from inversion of shear waveforms. Geophys. Res. Lett. 34:L21305
61. Kawai K, Sekine S, Fuji N, Geller RJ. 2009. Waveform inversion for D" structure beneath northern Asia using Hi-net tiltmeter data. Geophys. Res. Lett. 36:L20314
62. Kawai K, Takeuchi N, Geller RJ, Fuji N. 2007b. Possible evidence for a double crossing phase transition in D" beneath Central America from inversion of seismic waveforms. Geophys. Res. Lett. 34:L09314
63. Kawai K, Tsuchiya T. 2009. Temperature profile in the lowermost mantle from seismological and mineral physics joint modeling. Proc. Natl. Acad. Sci. USA 106:22119-23
64. Kellogg LH, Hager BH, van der Hilst RD. 1999. Compositional stratification in the deep mantle. Science 283:1881-84
65. Kito T, Korenaga J. 2010. Cross-correlation weighted migration: towards high resolution mapping of mantle heterogeneities. Geophys.J. Int. 181:1109-27
66. Kito T, Kruger F. 2001. Heterogeneities in D" beneath the southwestern Pacific inferred from scattered and reflected P-waves. Geophys. Res. Lett. 28:2545-48 (Pubitemid 32704438)
67. Kito T, Kruger F, Negishi H. 2004. Seismic heterogeneous structure in the lowermost mantle beneath the southwestern Pacific. J. Geophys. Res. 109:B09304
68. Kito T, Rietbrock A, Thomas C. 2007a. Slowness-backazimuth weighted migration: a new array approach to a high-resolution image. Geophys.J. Int. 169:1201-9 (Pubitemid 46894901)
69. Kito T, Rost S, Thomas C, Garnero EJ. 2007b. New insights into the P-and S-wave velocity structure of the D" discontinuity beneath the Cocos plate. Geophys.J. Int. 169:631-45 (Pubitemid 46604998)
70. Kito T, Thomas C, Rietbrock A, Garnero EJ, Nippress SEJ, Heath AE. 2008. Seismic evidence for a sharp lithospheric base persisting to the lowermost mantle beneath the Caribbean. Geophys. J. Int. 174:1019-28
71. Konishi K, Kawai K, Geller RJ, Fuji N 2009. MORB in the lowermost mantle beneath the western Pacific: evidence from waveform inversion. Earth Planet. Sci. Lett. 278:219-25
72. Kruger F, Scherbaum F, Weber M, Schlittenhardt J. 1996. Analysis of asymmetric multipathing with a generalization of the double-beam method. Bull. Seismol. Soc. Am. 86:737-49
73. Kruger F, Weber M, Scherbaum F, Schlittenhardt J. 1993. Double beam analysis of anomalies in the core-mantle boundary region. Geophys. Res. Lett. 20:1475-78 (Pubitemid 24418863)
74. Kruger F, Weber M, Scherbaum F, Schlittenhardt J. 1995. Normal and inhomogeneous lowermost mantle and core-mantle boundary under the Arctic and Northern Canada. Geophys.J. Int. 122:637-58
75. Kuo BY, Garnero EJ, Lay T. 2000. Tomographic inversion ofS-SKS times for shear velocity heterogeneity in D": degree 12 and hybrid models. J. Geophys. Res. 105:28139-57 (Pubitemid 32184153)
76. Kuo C, Romanowicz B. 2002. On the resolution of density anomalies in the Earth's mantle using spectral fitting of normal-mode data. Geophys. J. Int. 150:162-79 (Pubitemid 34789250)
77. Kustowski B, Ekstrom G, Dziewonski AM. 2008. Anisotropic shear-wave velocity structure of the Earth's mantle: a global model. J. Geophys. Res. 113:B06306
78. Labrosse S, Hernlund JW, Coltice N. 2007. A crystallizing dense magma ocean at the base of the Earth's mantle. Nature 450:866-69 (Pubitemid 350231323)
79. Lay T. 2008. Sharpness of the D" discontinuity beneath the Cocos Plate: implications for the perovskite to postperovskite phase transition. Geophys. Res. Lett. 35:L03304
80. Lay T, Garnero EJ. 2004. Core-mantle boundary structures and processes. In The State of the Planet: Frontiers and Challenges in Geophysics, ed. RSJ Sparks, CJ Hawkesworth, Geophys. Monogr. 150:25-41. Washington, DC: AGU
81. Lay T, Garnero EJ. 2007. Reconciling the postperovskite phase with seismological observations of lowermost mantle structure. In Post-Perovskite: The Last Mantle Phase Transition, ed. K Hirose, J Brodholt, T Lay, D Yuen, Geophys. Monogr. 174:129-53. Washington, DC: AGU
82. Lay T, Garnero EJ, Russell S. 2004a. Lateral variation of the D" discontinuity beneath the Cocos Plate. Geophys. Res. Lett. 31:L15612
83. Lay T, Garnero EJ, Williams Q. 2004b. Partial melting in a thermo-chemical boundary layer at the base of the mantle. Phys. Earth Planet. Inter. 146:441-67 (Pubitemid 39039697)
84. Lay T, Heinz D, Ishii M, Shim S-H, Tsuchiya T, et al. 2005. Multidisciplinary impact of the lower mantle perovskite phase transition. Eos Trans. AGU86(1):1, 5
85. Lay T, Helmberger DV. 1983a. A lower mantle S-wave triplication and the velocity structure of D". Geophys. J. R. Astron. Soc. 75:799-837
86. Lay T, Helmberger DV. 1983b. The shear wave velocity gradient at the base of the mantle. J. Geophys. Res. 88:8160-70 (Pubitemid 14454298)
87. Lay T, Hernlund J, Buffett BA. 2008. Core-mantle boundary heat flow. Nat. Geosci. 1:25-32
88. Lay T, Hernlund J, Garnero EJ, Thorne MS. 2006. A postperovskite lens and D" heat flux beneath the central Pacific. Science 314:1272-76 (Pubitemid 44846395)
89. Lay T, Young CJ. 1996. Imaging scattering structures in the lower mantle by migration of long-period S waves. J. Geophys. Res. 101:20023-40
90. Li C, van der Hilst RD, Engdahl ER, Burdick W. 2008. A new global model for P wave speed variations in Earth's mantle. Geochem. Geophys. Geosyst. 9:Q05018
91. Luo SN, Ni SD, Helmberger DV. 2001. Evidence for a sharp lateral variation of velocity at the core-mantle boundary from multipathed PKPab. Earth Planet. Sci. Lett. 189:155-64 (Pubitemid 32710501)
92. Mao WL, Mao HK, Sturhahn W, Zhao J, Prakapenka VB, et al. 2006. Iron-rich postperovskite and the origin of ultralow-velocity zones. Science 312:564-65
93. McNamara AK, Garnero EJ, Rost S. 2010. Tracking deep mantle reservoirs with ultra-low velocity zones. Earth Planet. Sci. Lett. 299:1-9
94. McNamara AK, van Keken PE, Karato SI. 2003. Development of finite strain in the convecting lower mantle and its implications for seismic anisotropy. J. Geophys. Res. 108(B5):2230
95. McNamara AK, Zhong S. 2004. Thermochemical structures within a spherical mantle: superplumes or piles? J. Geophys. Res. 109:B07402
96. McNamara AK, Zhong S. 2005. Thermochemical structures beneath Africa and the Pacific Ocean. Nature 437:1136-39 (Pubitemid 41509348)
97. Megnin C, Romanowicz B. 2000. The three-dimensional shear velocity structure of the mantle from the inversion of body, surface and higher-mode waveforms. Geophys. J. Int. 143:709-28 (Pubitemid 32015444)
98. Miller MS, Niu F. 2008. Bulldozing the core-mantle boundary: localized seismic scatterers beneath the Caribbean Sea. Phys. Earth Planet. Int. 170:89-94
99. Murakami M, Hirose K, Kawamura K, Sata N, Ohishi Y. 2004. Postperovskite phase transition in MgSiO3. Science 304:855-58
100. Ni S, Ding X, Helmberger DV. 2000. Constructing synthetics from deep earth tomographic models. Geophys. J. Int. 14:71-82 (Pubitemid 30147586)
101. Ni S, Helmberger DV. 2003a. Seismological constraints on the South African superplume; could be the oldest distinct structure on earth. Earth Planet. Sci. Lett. 206:119-31 (Pubitemid 36137962)
102. Ni S, Helmberger DV. 2003b. Ridge-like lower mantle structure beneath South Africa. J. Geophys. Res. 108(B2):2094
103. Ni S, Helmberger DV, Tromp J. 2005. Three-dimensional structure of the Africa superplume from waveform modeling. Geophys. J. Int. 161:283-94 (Pubitemid 40706667)
104. Ni S, Tan E, Gurnis M, Helmberger DV. 2002. Sharp sides to the African superplume. Science 296:1850-52 (Pubitemid 34596267)
105. Niu F, Wen L. 2001. Strong seismic scatterers near the core-mantle boundary west of Mexico. Geophys. Res. Lett. 24:3557-60 (Pubitemid 32989805)
106. Ohta K, Hirose K, Lay T, Sata N, Ohishi Y. 2008. Phase transitions in pyrolite and MORB at lowermost mantle conditions: implications for a MORB-rich pile above the core-mantle boundary. Earth Planet. Sci. Lett. 267:107-17
107. Panning M, Romanowicz B. 2006. A three-dimensional radially anisotropic model of shear velocity in the whole mantle. Geophys. J. Int. 167:361-79 (Pubitemid 44489897)
108. Persch SE, Vidale JE, Earle PS. 2001. Absence of short-period ULVZ precursors to PcP and ScP from two regions of the CMB. Geophys. Res. Lett. 28:387-90
109. Reasoner C, RevenaughJ. 1999. Short-period P-wave constraints on D" reflectivity. J. Geophys. Res. 10:955-61
110. Reasoner C, Revenaugh J. 2000. ScP constraints on ultralow velocity zone density and gradient thickness beneath the Pacific. J. Geophys. Res. 105:28173-82 (Pubitemid 32184155)
111. Resovsky J, Trampert J. 2003. Using probabilistic seismic tomography to test mantle velocity-density relationships. Earth Planet. Sci. Lett. 215:121-34 (Pubitemid 37257174)
112. Revenaugh JS, Meyer R. 1997. Seismic evidence of partial melt within a possibly ubiquitous low-velocity layer at the base of the mantle. Science 277:670-73 (Pubitemid 27373909)
113. Ritsema J, Garnero E, Lay T. 1997. A strongly negative shear velocity gradient in the lowermost mantle beneath the Pacific. J. Geophys. Res. 102:20395-411
114. Ritsema J, Ni S, Helmberger DV, Crotwell HP. 1998. Evidence for strong shear velocity reductions and velocity gradients in the lower mantle beneath Africa. Geophys. Res. Lett. 25:4245-48 (Pubitemid 29178285)
115. Ritsema J, van Heijst HJ. 2000. Seismic imaging of structural heterogeneity in Earth's mantle: evidence for large-scale mantle flow. Sci. Prog. 83:243-59
116. Romanowicz B. 2001. Can we resolve 3D density heterogeneity in the lower mantle? Geophys. Res. Lett. 28:1107-10 (Pubitemid 32569218)
117. Rondenay S, Cormier VF, Van Ark EM. 2010. SKS and SPdKS sensitivity to two-dimensional ultralow-velocity zones. J. Geophys. Res. 115:B04311
118. Rondenay S, Fischer KM. 2003. Constraints on localized core-mantle boundary structure from multichannel, broadband SKS coda analysis. J. Geophys. Res. 108:2537
119. Rost S, Garnero EJ, Stefan W. 2010a. Thin and intermittent ultralow-velocity zones. J. Geophys. Res. 115:B06312
120. Rost S, Garnero EJ, Thorne MS, Hutko AR. 2010b. On the absence of an ultralow-velocity zone in the North Pacific. J. Geophys. Res. B04312
121. Rost S, Garnero EJ, Williams Q. 2006. Fine-scale ultralow-velocity zone structure from high-frequency seismic array data. J. Geophys. Res. 111:B09310
122. Rost S, Garnero EJ, Williams Q. 2008. Seismic array detection of subducted oceanic crust in the lower mantle. J. Geophys. Res. 113:B06303
123. Rost S, Garnero EJ, Williams Q, Manga M. 2005. Seismic constraints on a possible plume root at the core-mantle boundary. Nature 435:666-69 (Pubitemid 40825509)
124. Rost S, RevenaughJ. 2001. Seismic detection of rigid zones at the top of the core. Science 294:1911-14 (Pubitemid 33101584)
125. Rost S, Revenaugh J. 2003. Small-scale ultralow-velocity zone structure imaged by ScP. J. Geophys. Res. 108:2056
126. Rost S, Thomas C. 2002. Array seismology: methods and applications. Rev. Geophys. 40:1-27
127. Rost S, Thomas C. 2010. High resolution CMB imaging from migration of short-period core reflected phases. Phys. Earth Planet. Inter. 183:143-50
128. Russell SA, Reasoner C, Lay T, RevenaughJ. 2001. Coexisting shear-and compressional-wave seismic velocity discontinuities beneath the central Pacific. Geophys. Res. Lett. 28:2281-84 (Pubitemid 32596255)
129. Saltzer RL, van der Hilst RD, Karason H. 2001. Comparing P and S wave heterogeneity in the mantle. Geophys. Res. Lett. 28:1335-38 (Pubitemid 32579677)
130. Scherbaum F, Kruger F, Weber M. 1997. Double beam imaging: mapping lower mantle heterogeneities using combinations of source and receiver arrays. J. Geophys. Res. 102:507-22
131. Schimmel M, Paulssen H. 1997. Noise reduction and detection of weak, coherent signals through phase-weighted stack. Geophys. J. Int. 130:497-505
132. Sidorin I, Gurnis M, Helmberger DV. 1999. Evidence for a ubiquitous seismic discontinuity at the base of the mantle. Science 286:1326-31
133. Simmons NA, Grand SP. 2002. Partial melting in the deepest mantle. Geophys. Res. Lett. 29:1552
134. Stutzmann E, Vinnik L, Ferreira A, Singh S. 2000. Constraint on the S-wave velocity at the base of the mantle. Geophys. Res. Lett. 27:1571-74 (Pubitemid 32040488)
135. Sun D, Helmberger D. 2008. Lower mantle tomography and phase change mapping. J. Geophys. Res. 113:B10305
136. Sun D, Helmberger D, Gurnis M. 2010. A narrow, mid-mantle plume below southern Africa. Geophys. Res. Lett. 37:L09302
137. Sun D, Helmberger D, Ni S, Bower D. 2009. Direct measures of lateral velocity variation in the deep Earth. J. Geophys. Res. 114:B05303
138. Sun D, Song TRA, Helmberger D. 2006. Complexity of D" in the presence of slab-debris and phase changes. Geophys. Res. Lett. 33:L12S07
139. Sun D, Tan E, Helmberger DV, Gurnis M. 2007. Seismological support for the metastable superplume model, sharp features, and phase changes within the lower mantle. Proc. Natl. Acad. Sci. USA 104:9151-55 (Pubitemid 47185748)
140. Sun X, Song X, Zheng S, Helmberger DV. 2007. Evidence for a chemical-thermal structure at base of mantle from sharp lateral P-wave variations beneath Central America. Proc. Natl. Acad. Sci. USA 104:26-30 (Pubitemid 46067979)
141. Takeuchi N. 2007. Whole mantle SH velocity model constrained by waveform inversion based on three-dimensional Born kernels. Geophys. J. Int. 169:1153-63 (Pubitemid 46894898)
142. Takeuchi N, Morita Y, Xuyen ND, Zung NQ. 2008. Extent of the low-velocity region in the lowermost mantle beneath the western Pacific detected by the Vietnamese Broadband Seismograph Array. Geophys. Res. Lett. 35:L05307
143. Tan E, Gurnis M. 2005. Metastable superplumes and mantle compressibility. Geophys. Res. Lett. 32:L20307
144. TanE, Gurnis M, HanL. 2002. Slabs in the lower mantle and their modulation of plume formation. Geochem. Geophys. Geosyst. 3:11067
145. Tanaka S. 2002. Very low shear wave velocity at the base of the mantle under the South Pacific superswell. Earth Planet. Sci. Lett. 203:879-93 (Pubitemid 35250118)
146. Thomas C, Garnero EJ, Lay T. 2004a. High-resolution imaging of lowermost mantle structure under the Cocos Plate. J. Geophys. Res. 109:B08307
147. Thomas C, Heesom T, Kendall JM. 2002. Investigating the heterogeneity of the D" region beneath the northern Pacific using a seismic array. J. Geophys. Res. 107(B11):2274
148. Thomas C, Kendall JM, Helffrich G 2009. Probing two low-velocity regions with PKP b-caustic amplitudes and scattering. Geophys. J. Int. 178:503-12
149. Thomas C, Kendall JM, Lowman J. 2004b. Lower-mantle seismic discontinuities and the thermal morphology of subducted slabs. Earth Planet. Sci. Lett. 225:105-13 (Pubitemid 39122628)
150. Thomas C, Weber M, Wicks CW, Scherbaum F. 1999. Small scatterers in the lower mantle observed at German broadband arrays. J. Geophys. Res. 104:15073-88
151. Thorne MS, Garnero EJ. 2004. Inferences on ultralow-velocity zone structure from a global analysis ofSPdKS waves. J. Geophys. Res. 109:B08301
152. Thorne MS, Garnero EJ, Grand SP. 2004. Geographic correlation between hot spots and deep mantle lateral shear-wave velocity gradients. Phys. Earth Planet. Inter. 146:47-63 (Pubitemid 38889328)
153. Thorne MS, Lay T, Garnero EJ, Jahnke G, Igel H. 2007. Seismic imaging of the laterally varying D" region beneath the Cocos Plate. Geophys. J. Int. 170:635-48 (Pubitemid 47108400)
154. To A, Romanowicz B, Capdeville Y, Takeuchi N. 2005. 3D effects of sharp boundaries at the borders of the African and Pacific Superplumes: observation and modeling. Earth Planet Sci. Lett. 233:137-53
155. Torsvik TH, Burke K, Steinberger B, Webb SJ, Ashwal LD. 2010. Diamonds sampled by plumes from the core-mantle boundary. Nature 466:352-55
156. Torsvik TH, Smethurst MA, Burke K, Steinberger B. 2006. Large igneous provinces generated from the margins of the large low-velocity provinces in the deep mantle. Geophys. J. Int. 167:1447-60 (Pubitemid 44869729)
157. Trampert J, Deschamps F, ResovskyJ, Yuen D. 2004. Probabilistic tomography maps chemical heterogeneities throughout the lower mantle. Science 306:853-56 (Pubitemid 39446990)
158. Trønnes RG 2009. Structure, mineralogy and dynamics of the lowermost mantle. Mineral. Petrol. 99:243-61
159. Van Der Hilst RD, de Hoop MV, Wang P, Shim SH, Ma P, Tenoria L. 2007. Seismostratigraphy and thermal structure of Earth's core-mantle boundary region. Science 315:1813-17 (Pubitemid 46580134)
160. Van Der Hilst RD, Karason H. 1999. Compositional heterogeneity in the bottom 1000 kilometers of Earth's mantle: toward a hybrid convection model. Science 283:1885-88
161. Wallace M, Thomas C. 2005. Investigating D" structure beneath the North Atlantic. Phys. Earth Planet. Inter. 151:115-27 (Pubitemid 40696848)
162. Wang P, de Hoop MV, van der Hilst RD. 2008. Imaging of the lowermost mantle (D") and the core-mantle boundary with SKKS coda waves. Geophys.J. Int. 175:103-15
163. Wang P, de Hoop MV, van der Hilst RD, Ma P, Tenorio L. 2006. Imaging of structure at and near the core-mantle boundary using a generalized radon transform: 1. Construction of image gathers. J. Geophys. Res. 111:B12304
164. Wang Y, Wen L. 2004. Mapping the geometry and geographic distribution of a very low velocity province at the base of the Earth's mantle. J. Geophys. Res. 109:B10305
165. Wang Y, Wen L. 2007. Geometry and P and S velocity structures of the "African Anomaly." J. Geophys. Res. 112:B05313
166. Weber M, Davis JP, Thomas C, Kruger F, Scherbaum F, et al. 1996. The structure of the lowermost mantle as determined from using seismic arrays. In Seismic Modeling of the Earth's Structure, ed. E Boschi, G Ekstrom, AMorelli, pp. 399-442. Rome: Inst. Naz. Geophys.
167. Wen L. 2000. Intense seismic scattering near the Earth's core-mantle boundary beneath the Comoros hotspot. Geophys. Res. Lett. 27:3627-30
168. Wen L. 2001. Seismic evidence for a rapidly varying compositional anomaly at the base of the Earth's mantle beneath the Indian ocean. Earth Planet. Sci. Lett. 194:83-95 (Pubitemid 34119997)
169. Wen L. 2002. An SHhybrid method and shear velocity structures in the lowermost mantle beneath the central Pacific and South Atlantic Oceans. J. Geophys. Res. 107(B3):2055
170. Wen L. 2006. A compositional anomaly at the Earth's core-mantle boundary as an anchor to the relatively slowly moving surface hotspots and as source to the DUPAL anomaly. Earth Planet. Sci. Lett. 246:138-48 (Pubitemid 43793102)
171. Wen L, Helmberger DV 1998. Ultra-low velocity zones near the core-mantle boundary from broadband PKP precursors. Science 279:1701-3 (Pubitemid 28164462)
172. Wen L, Silver P, James D, Kuehnel R. 2001. Seismic evidence for a thermo-chemical boundary layer at the base of the Earth's mantle. Earth Planet. Sci. Lett. 189:141-53 (Pubitemid 32710500)
173. Wicks JK, Jackson JM, Sturhahn W. 2010. Very low sound velocities in iron-rich (Mg,Fe)O: implications for the core-mantle boundary region. Geophys. Res. Lett. 37:L15304
174. Wookey J, Stackhouse S, Kendall JM, Brodholt J, Price GD. 2005. Efficacy of the postperovskite phase as an explanation for lowermost-mantle seismic properties. Nature 438:1004-7 (Pubitemid 43093971)
175. Wright C, Kuo BY. 2007. The P-wavespeed structure in the lowermost 700 km of the mantle belowthe central part of the Indian Ocean. Phys. Earth Planet. Inter. 161:243-66 (Pubitemid 46657040)
176. Wysession ME, Fischer KM, Al-Eqabi GI, Shore PJ, Gurari I. 2001. Using MOMA broadband array ScS-S data to image smaller-scale structures at the base of the mantle. Geophys. Res. Lett. 28:867-70 (Pubitemid 32569260)
177. Xu Y, Koper KD. 2009. Detection of a ULVZ at the base of the mantle beneath the northwest Pacific. Geophys. Res. Lett. 36:L17301
178. Yamada A, Nakanishi I. 1996. Detection of P-wave reflection in D" beneath the south-western Pacific using double-array stacking. Geophys. Res. Lett. 23:1553-56
179. Yamada A, Nakanishi I. 1998. Short-wavelength lateral variation of a D" P-wave reflector beneath the southwestern Pacific. Geophys. Res. Lett. 25:4545-48 (Pubitemid 29212527)
180. Young CJ, Lay T. 1990. Multiple phase analysis of the shear velocity structure in the D" region beneath Alaska. J. Geophys. Res. 95:17385-402
181. Zhao D. 2004. Global tomographic images of mantle plumes and subducting slabs: insight into deep Earth dynamics. Phys. Earth Planet. Inter. 146:3-34 (Pubitemid 38889326)