Skip to main content
SpringerLink
Log in

Magnetic investigation and 2½ D gravity profile modelling across the Beattie magnetic anomaly in the southeastern Karoo Basin, South Africa

  • Research Article
  • Published:
Acta Geophysica Aims and scope Submit manuscript

Abstract

The southeastern Karoo Basin is considered to be one of the most prospective areas for shale gas exploration in South Africa. An interesting magnetic anomaly, the Beattie magnetic anomaly (BMA), and geologic intrusions are seen on the magnetic map. To date, the source of the BMA and interconnectivity of the igneous intrusions are not well understood. In this study, we investigate the interconnectivity of the igneous intrusions and possible location of the source of the BMA using gravity and magnetic methods. The gravity model results showed that igneous intrusions are interconnected at depth, which probably pose threat by increasing the risk of fracking the Karoo for shale gas exploration. The magnetic results revealed that the BMA becomes stronger with depth. The average depths to the top of the shallow and deep magnetic sources were estimated to be approximately 0.6 and 15 km, respectively.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18

Similar content being viewed by others

References

  • Beattie JC (1909) Report of a magnetic survey of South Africa. R Soc Lond Publ 76:1–35

    Google Scholar 

  • Catuneanu O, Hancox PJ, Rubidge BS (1998) Reciprocal flexural behaviour and contrasting stratigraphies: a new basin development model for the Karoo retroarc foreland system, South Africa. Basin Res 10:417–439. doi:10.1046/j.1365-2117.1998.00078.x

    Article  Google Scholar 

  • Catuneanu O, Hancox PJ, Cairncross B, Rubidge BS (2002) Foredeep submarine fans and forebulge deltas: orogenic off-loading in the underfilled Karoo Basin. J Afr Earth Sci 35:489–502. doi:10.1016/S0899-5362(02)00154-9

    Article  Google Scholar 

  • Catuneanu O, Wopfner H, Eriksson PG, Cairncross B, Rubidge BS, Smith RMH, Hancox PJ (2005) The Karoo basins of south-central Africa. J Afr Earth Sci 43:211–253. doi:10.1016/j.jafrearsci.2005.07.007

    Article  Google Scholar 

  • Chevallier L, Woodford AC (1999) Morpho-tectonics and mechanism of emplacement of the dolerite rings and sills of the western Karoo, South Africa. S Afr J Geol 102:43–54

    Google Scholar 

  • Chevallier L, Goedhart M, Woodford AC (2001) The influences of dolerite sill and ring complexes on the occurrence of groundwater in Karoo fractured aquifers: a morpho-tectonic approach. Water Res Comm Rep 37(1):4–146

    Google Scholar 

  • Cook FA, White DJ, Jones AG, Eaton DW, Hall J, Clowes RM (2010) How the crust meets the mantle: lithoprobe perspectives on the Mohorovicić discontinuity and crust–mantle transition. Can J Earth Sci 47:315–351. doi:10.1139/E09-076

    Article  Google Scholar 

  • Council for Geoscience (1995) Geological map of South Africa 1:250000, Sheet 2922, Prieska. Geological Survey of South Africa, Pretoria

    Google Scholar 

  • De Beer JH, Gough DI (1980) Conductive structures in southernmost Africa: a magnetometer array study. Geophys J R Astron Soc 63:479–495. doi:10.1111/j.1365-246X.1980.tb02633.x

    Article  Google Scholar 

  • De Beer JH, Meyer R (1983) Geo-electrical and gravitational characteristics of the Namaqua–Natal mobile belt and its boundaries. Spec Publ Geol Soc S Afr 10:91–100

    Google Scholar 

  • De Beer JH, Meyer R (1984) Geophysical characteristics of the Namaqua–Natal mobile belt and its boundaries, South Africa. J Geodyn 1:473–494. doi:10.1016/0264-3707(84)90020-6

    Article  Google Scholar 

  • De Beer JH, Van Zijl JSV, Gough DI (1982) The southern cape conductive belt (South Africa): its composition, origin and tectonic significance. Tectonophysics 83:205–225. doi:10.1016/0040-1951(82)90019-1

    Article  Google Scholar 

  • De Wit MJ, Horsfield B (2006) Inkaba yeAfrica Project surveys sector of Earth from core to space. EOS Trans Am Geophys Union 87(11):113–117. doi:10.1029/2006EO110002

    Article  Google Scholar 

  • De Wit MJ, Ransome IG (1992) Regional inversion tectonics along the southern margin of Gondwana. In: De Wit MJ, Ransome IG (eds) Inversion tectonics of the cape fold belt, Karoo and Cretaceous Basins of Southern Africa. Balkema, Rotterdam, pp 15–22

    Google Scholar 

  • Du Plessis A, Simpson ESW (1974) Magnetic anomalies associated with the southeastern continental margin of South Africa. Mar Geophys Res 2:99–110. doi:10.1007/BF00340028

    Article  Google Scholar 

  • Flint SS, Hodgson DM, Sprague AR, Brunt RL, Van Der Merwe WC, Figueiredo J, Prélat A, Box D, Di Celma C, Kavanagh JP (2011) Depositional architecture and sequence stratigraphy of the Karoo basin floor to shelf edge succession, Laingsburg depocentre, South Africa. Mar Petrol Geol 28:658–674. doi:10.1016/j.marpetgeo.2010.06.008

    Article  Google Scholar 

  • Fuller BD (1967) Two-dimensional frequency analysis and design of grid operators. In: Hansen DA, Heinrichs WE, Holmer RC, MacDougall RE, Rogers GR, Sumner JS, Ward SH (eds) Society of exploration geophysicists' mining geophysics, vol 2. pp 658–708

  • Geel C, Schulz HM, Booth P, De Wit M, Horsfield B (2013) Shale gas characteristics of Permian black shales in South Africa: results from recent drilling in the Ecca Group (Eastern Cape). Energy Procedia 40:256–265. doi:10.1016/j.egypro.2013.08.030

    Article  Google Scholar 

  • Gough D, De Beer JH, Van Zijl J (1973) A magnetometer array study in southern Africa. Geophys J R Astron Soc 34:421–433. doi:10.1111/j.1365-246X.1973.tb02405.x

    Article  Google Scholar 

  • Gunn PJ (1972) Application of Wiener filters to transformations of gravity and magnetic data. Geophys Prospect 20:860–871. doi:10.1111/j.1365-2478.1972.tb00671.x

    Article  Google Scholar 

  • Hälbich IW (1983) A tectogenesis of the Cape Fold Belt (CFB). In: Söhnge APG, Hälbich IW (eds) Geodynamics of the Cape Fold Belt. Special publications of the geological society of South Africa, vol 12. pp 165–175

  • Hälbich IW (1993) The Cape Fold Belt—Agulhas Bank transect. In: Hälbich IW (ed) Cape Fold Belt—Agulhas Bank transect across Gondwana suture, Southern Africa. American Geophysical Union, Washington, pp 3–18. doi:10.1002/9781118668016.ch1

    Chapter  Google Scholar 

  • Harvey JD, De Wit MJ, Stankiewicz J, Doucouré CM (2001) Structural variations of the crust in the Southwest Cape, deduced from seismic receiver functions. S Afr J Geol 104:231–242. doi:10.2113/1040231

    Article  Google Scholar 

  • Hynes A, Snyder DB (1995) Deep-crustal mineral assemblages and potential for crustal rocks below the Moho in the Scottish Caledonides. Geophys J Int 123(2):323–339. doi:10.1111/j.1365-246X.1995.tb06857.x

    Article  Google Scholar 

  • Johnson MR, van Vuuren CJ, Hegenberger WF, Key R, Shoko U (1996) Stratigraphy of the Karoo Supergroup in southern Africa: an overview. J Afr Earth Sci 23:3–15. doi:10.1016/S0899-5362(96)00048-6

    Article  Google Scholar 

  • Johnson MR, van Vuuren CJ, Visser JNJ, Cole DI, Wickens HV, Christie ADM, Roberts DL, Brandl G (2006) Sedimentary rocks of the Karoo Supergroup. In: Johnson MR, Anhaeusser CR, Thomas RL (eds) The geology of South Africa. Geological Society of South Africa, Johannesburg/Council for Geoscience, Pretoria, pp 461–500

    Google Scholar 

  • Li X (2006) Understanding 3D analytic signal amplitude. Geophysics 71(2):13–16. doi:10.1190/1.2184367

    Article  Google Scholar 

  • Lindeque A, Ryberg T, Weber M, Stankiewicz J, De Wit MJ (2007) Deep crustal seismic reflection experiment across the Southern Karoo basin, South Africa. S Afr J Geol 110:419–438. doi:10.2113/gssajg.110.2-3.419

    Article  Google Scholar 

  • Lindeque A, De Wit MJ, Ryberg T, Weber M, Chevallier L (2011) Deep crustal profile across the Southern Karoo basin and Beattie magnetic anomaly, South Africa: an integrated interpretation with tectonic implications. S Afr J Geol 114:265–292. doi:10.2113/gssajg.114.3-4.265

    Article  Google Scholar 

  • Maus S, Dimri V (1996) Depth estimation from the scaling power spectrum of potential fields. Geophys J Int 124(1):113–120. doi:10.1111/j.1365-246X.1996.tb06356.x

    Article  Google Scholar 

  • Mjelde R, Goncharov A, Müller RD (2013) The Moho: boundary above upper mantle peridotites or lower crustal eclogites, a global review and new interpretations for passive margins. Tectonophysics 609:636–650. doi:10.1016/j.tecto.2012.03.001

    Article  Google Scholar 

  • Pángaro F, Ramos VA (2012) Palaeozoic crustal blocks of onshore and offshore central Argentina: new pieces of the southwestern Gondwana collage and their role in the accretion of Patagonia and the evolution of Mesozoic south Atlantic sedimentary basins. Mar Petrol Geol 371:145–162. doi:10.1016/j.marpetgeo.2012.05.010

    Google Scholar 

  • Pitts B, Mahler M, de Beer J, Gough D (1992) Interpretation of magnetic, gravity and magnetotelluric data across the Cape Fold Belt and Karoo Basin. In: De Wit M, Ransome I (eds) Inversion tectonics of the Cape Fold Belt, Karoo and Cretaceous basins of southern Africa. Balkema, Rotterdam, Netherlands, pp 27–32

  • Rabeh T, Abdallatif T, Mekkawi M, Khalil A, El-Emam A (2008) Magnetic data interpretation and depth estimation constraints: a correlative study on magnetometer and gradiometer data. NRIAG J Geophys Spec Issue 6:185–209

    Google Scholar 

  • Rowsell DM, De Swardt AMJ (1976) Diagenesis in Cape and Karroo sediments, South Africa, and its bearing on their hydrocarbon potential. Trans Geol Soc S Afr 79:81–145

    Google Scholar 

  • Rust IC (1973) The evolution of the Paleozoic Cape Basin, southern margin of Africa. In: Nairn AEM, Stehli FG (eds) The ocean basins and margins, vol 1, the South Atlantic. Springer, New York, pp 247–276. doi:10.1007/978-1-4684-3030-1_6

    Google Scholar 

  • Scheiber-Enslin SE, Webb SJ, Ebbing J (2014) Geophysically plumbing the Main Karoo Basin, South Africa. S Afr J Geol 117(2):275–300. doi:10.2113/gssajg.117.2.275

    Article  Google Scholar 

  • Schreiber-Enslin S, Ebbing J, Eberle D, Webb S (2013) 3D Geophysical modelling of the Beattie magnetic anomaly and Karoo Basin, South Africa. Geophys Res Abstr 15:EGU2013-4407

    Google Scholar 

  • Smith RMH, Erickson PG, Botha WJ (1993) A review of the stratigraphy and sedimentary environments of the Karoo-aged basins of Southern Africa. J Afr Earth Sci 132:143–169. doi:10.1016/0899-5362(93)90164-L

    Article  Google Scholar 

  • Spector A, Grant FS (1970) Statistical models for interpreting aeromagnetic data. Geophysics 35(2):293–302. doi:10.1190/1.1440092

    Article  Google Scholar 

  • Stankiewicz J, De Wit MJ (2013) 3.5 billion years of reshaped Moho, southern Africa. Tectonophysics 609:675–689. doi:10.1016/j.tecto.2013.08.033

    Article  Google Scholar 

  • Stankiewicz J, Ryberg T, Schulze A, Lindeque A, Weber MH, De Wit MJ (2007) Initial results from wide-angle seismic refraction lines in the Southern Cape. S Afr J Geol 110:407–418

    Article  Google Scholar 

  • Stollhofen H, Stanistreet IG, Bangert B, Grill H (2000) Tuffs, tectonism and glacially related sea-level changes, Carboniferous–Permian, southern Namibia. Palaeogeogr Palaeoclimatol Palaeoecol 161(1–2):127–150. doi:10.1016/S0031-0182(00)00120-6

    Article  Google Scholar 

  • Svensen H, Planke S, Chevallier L, Malthe-Sorenssen A, Corfu F, Jamtveit B (2007) Hydrothermal venting of greenhouse gases triggering Early Jurassic global warming. Earth Planet Sci Lett 256(3/4):554–566

    Article  Google Scholar 

  • Tankard AJ, Jackson MPA, Eriksson KA, Hobday DK, Hunter DR, Minter WEL (1982) Crustal evolution of Southern Africa. 3.8 billion years of earth history. Springer, New York, p 523

    Book  Google Scholar 

  • Tankard A, Welsink H, Aukes P, Newton R, Stettler E (2009) Tectonic evolution of the Cape and Karoo basins of South Africa. Mar Petrol Geol 26:1379–1412. doi:10.1016/j.marpetgeo.2009.01.022

    Article  Google Scholar 

  • Tankard A, Welsink H, Aukes P, Newton R, Stettler E (2012) Geodynamic interpretation of the Cape and the Karoo basins, South Africa. In: Regional geology and tectonics: phanerozoic passive margins, cratonic basins and global tectonics maps. Elsevier, pp 868–945. doi:10.1016/B978-0-444-56357-6.00022-6

  • Tedla GE, Van Der Meijde M, Nyblade AA, Van Der Meer FD (2011) A crustal thickness map of Africa derived from a global gravity field model using Euler deconvolution. Geophys J Int 187:1–9. doi:10.1111/j.1365-246X.2011.05140.x

    Article  Google Scholar 

  • Thybo H, Artemieva IM (2014) Moho and magmatic underplating in continental lithosphere. Tectonophysics 609:605–619. doi:10.1016/j.tecto.2013.05.032

    Article  Google Scholar 

  • Turner BR (1999) Tectono-stratigraphical development of the upper Karoo foreland basin: orogenic unloading versus thermally-induced Gondwana rifting. J Afr Earth Sci 28:215–238. doi:10.1016/S0899-5362(99)00025-1

    Article  Google Scholar 

  • Van Der Voort I (2001), Risk based decision tool for managing and protecting groundwater resources. Ph.D. Thesis, University of the Free State, Bloemfontein

  • Veevers JJ, Cole DI, Cowan EJ (1994) Southern Africa: Karoo Basin and Cape Fold Belt. GSA Mem 184:223–280. doi:10.1130/MEM184-p223

    Google Scholar 

  • Visser JNJ (1987) The palaeogeography of part of south-western Gondwana during the Permo-Carboniferous glaciation. Palaeogeogr Palaeoclimatol Palaeocol 61:205–219. doi:10.1016/0031-0182(87)90050-2

    Article  Google Scholar 

  • Visser JNJ (1995) Post-glacial Permian stratigraphy and geography of southern and central Africa: boundary conditions for climatic modelling. Palaeogeogr Palaeoclimatol Palaeocol 118:213–243. doi:10.1016/0031-0182(95)00008-3

    Article  Google Scholar 

  • Visser JNJ, Praekelt HE (1996) Subduction, mega-shear systems and Late Palaeozoic basin development in the African segment of Gondwana. Geol Rundsch 85:632–646. doi:10.1007/BF02440101

    Article  Google Scholar 

  • Weckmann U, Ritter O, Jung A, Branch T, De Wit M (2007a) Magnetotelluric measurements across the Beattie magnetic anomaly and the Southern Cape Conductive Belt, South Africa. J Geophys Res 112:416. doi:10.1029/2005JB003975

    Article  Google Scholar 

  • Weckmann U, Jung A, Branch T, Ritter O (2007b) Comparison of electrical conductivity structures and 2D magnetic modelling along two profiles crossing the Beattie Magnetic Anomaly, South Africa. S Afr J Geol 110:449–464. doi:10.2113/gssajg.110.2-3.449

    Article  Google Scholar 

  • Woodford AC, Chevallier LP (2002) Regional characterization and mapping of Karoo fractured aquifer systems—an integrated approach using a geographical information system and digital processing. Water Res Comm Rep 653/1/02:40–55

Download references

Acknowledgements

Thanks to Govan Mbeki Research and Development Centre (GMRDC) for supervisory link bursary and NRF bursary to Mr C. Baiyegunhi (UID: 101980). The authors are grateful to Fugro Airborne Surveys, Council for Geoscience for supplying the geophysical data. Geosoft is also appreciated for providing the “Extended GM-SYS” that was used for the modelling. We thank the editors and anonymous reviewers for their constructive comments, which helped us to improve the manuscript.

Author information

Authors and Affiliations

  1. Department of Geology, Faculty of Science and Agriculture, University of Fort Hare, Alice, Eastern Cape Province, South Africa

    Christopher Baiyegunhi & Oswald Gwavava

Authors
  1. Christopher Baiyegunhi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Oswald Gwavava
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Christopher Baiyegunhi.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Baiyegunhi, C., Gwavava, O. Magnetic investigation and 2½ D gravity profile modelling across the Beattie magnetic anomaly in the southeastern Karoo Basin, South Africa. Acta Geophys. 65, 119–138 (2017). https://doi.org/10.1007/s11600-017-0011-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11600-017-0011-3

Keywords

Search

Navigation