Data Services Products: emc-AFRP20 An absolute P-wave speed tomographic model with focus on African mantle structure, provided with and without crustal correction

Summary

AFRP20 (Boyce et al., 2021), is an absolute P-wavespeed tomographic model with focus on African mantle structure, provided with and without crustal correction.

Description

Name AFRP20
Title An absolute P-wave speed tomographic model with focus on African mantle structure, provided with and without crustal correction
Type 3-D Tomography Earth Model
Sub Type P-wave velocity
Year 2021
Data Revision r.0.0 (revision history)
 
Short Description   AFRP20_RF_CR1 is an adaptively parameterized, global absolute P-wave tomographic model following the methodology of Li et al., (2008). The crustal correction implemented in this model is described in the manuscript and supplementary material. ak135 (Kennett et al., 1995) is used as the global reference model. New data has been added in Africa, so we provide only the African component of the model. While the adaptively parameterized grids at upper mantle depths can be found in the supplementary material of the manuscript, here we provide the model sampled at 0.25×0.25 degrees and 50km depth to facilitate smooth plotting. The 3D grid contains the columns: depth (km), latitude (deg), longitude (deg), dVp (percentage relative to ak135), vp (absolute vp in km/s).
 
AFRP20 is an identical tomographic model to that above but no crustal correction is implemented.
 
Also available is a resolution/illumination mask for the upper part of the model (AFRP20_MASK). Regions sampled by the ray paths added in the AFRP20 models are calculated following the procedure outlined in Section 12 of the supplementary material that accompanies the main paper. The global data set will of course further illuminate the mantle wave speed structure so this acts to show the areas better resolved using the new data. Regions where the mask is on (i.e. equal to 1) are regions of lower confidence or poor illumination. Regions where the mask is off (i.e. equal to 0) are regions of higher confidence or good illumination. The 3D grid contains the columns: depth (km), latitude (deg), longitude (deg), mask on (1/0).
 
Authors: A. Boyce:
University of Cambridge, Department of Earth Science, Bullard Laboratories, Madingley Road, Cambridge, CB3 0EZ, UK.
I.D. Bastow:
Department of Earth Science and Engineering, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2BP, UK.
S. Cottaar:
University of Cambridge, Department of Earth Science, Bullard Laboratories, Madingley Road, Cambridge, CB3 0EZ, UK.
R. Kounoudis:
Department of Earth Science and Engineering, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2BP, UK.
J. Guilloud De Courbeville:
Department of Earth Science and Engineering, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2BP, UK.
E. Caunt:
Department of Earth Science and Engineering, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2BP, UK.
S. Desai:
Department of Earth Science and Engineering, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2BP, UK.

 
Previous Model None
Reference Model ak135
Model Download AFRP20-MOD-3D.r0.0.nc (see metadata ), is the netCDF 3 Classic file for AFRP20.
AFRP20-RF-CR1-MOD-3D.r0.0.nc (see metadata ), is the netCDF 3 Classic file for AFRP20_RF_CR1.
AFRP20-MASK-3D.r0.0.nc (see metadata ), is the netCDF 3 Classic file for AFRP20_MASK.
AFRP20_Original_model.tar.gz is a bundle of the original model files in text format (more information)
Model Homepage https://alistairboyce11.github.io/
Depth Coverage From 50 km to 2850 km
Area Africa (latitude: -44° to 44°, longitude: -24° to 64°)
 
Data Set Description Our global dataset of absolute arrival-time picks includes P, PP, Pn, Pg, pP, PKP, PKiKP and PKIKP phases from the “EHB” database (Engdahl et al., 1998) spanning the period 1964−2007 (Li et al., 2008). We improve resolution in Africa by incorporating numerous smaller regional seismic networks. These total 87,184 P arrivals from 3089 earthquakes recorded in Africa at 1,254 stations over the period 1994-2019. Further details on analysis of these datasets can be found in the main manuscript.
 

AFRP20 African tomographic model
AFRP20 African tomographic model including the crustal correction at upper mantle depths of 50km, 100km, 200km and 300km (a-d) plotted as percentage deviation from ak135 (dVp = +/- 1.5%). Gray regions are not constrained by our new AARM-derived African data set (see Section 12 of the supplementary material that accompanies the main paper), only by the global data set (Li et al., 2008). Please see the referenced manuscript for further information.

Citations and DOIs

To cite the original work behind this Earth model:

  • Boyce, A. Bastow, I.D. Cottaar, S. Kounoudis, R. Guilloud De Courbeville, J. Caunt, E. Desai, S. (2021), AFRP20: New P-wavespeed Model for the African Mantle Reveals Two Whole-Mantle Plumes Below East Africa and Neoproterozoic Modification of the Tanzania Craton, Geochem. Geophys. Geosyst., https://doi.org/10.1029/2020GC009302.

To cite IRIS DMC Data Products effort:

  • Trabant, C., A. R. Hutko, M. Bahavar, R. Karstens, T. Ahern, and R. Aster (2012), Data Products at the IRIS DMC: Stepping Stones for Research and Other Applications, Seismological Research Letters, 83(5), 846–854, https://doi.org/10.1785/0220120032.

DOI for this EMC webpage: https://doi.org/10.17611/dp/emc.2021.afrp20bea.1

References

  • Engdahl, et al., (1998). Global teleseismic earthquake relocation with improved travel times and procedures for depth determination. Bull. Seismol. Soc. Am. 88, 722–743.

Credits

  • r.0.0 model provided by Alistair Boyce.

Revision History

revision r.0.0: uploaded February 1, 2021.

Timeline

2021-02-01
online

Categories

Page built 08:24:48 | v.b'108166