Skip to main content
SpringerLink
Log in

Scattering of magnetic fabrics in the Cambrian alkaline granite of Meruoca (Ceará state, northeastern Brazil)

  • Review Article
  • Published:
International Journal of Earth Sciences Aims and scope Submit manuscript

Abstract

Anisotropy of magnetic susceptibility (AMS) applied to an alkaline granite from Meruoca (NE Brazil) recorded weak anisotropies, typically below 4%, and a considerable dispersion of the AMS axes. Red-clouded feldspars and clots of metasomatic minerals enclosed in magmatic crystals indicate that hydrothermal fluids altered the granite. U–Pb isotopic data show high-common Pb on zircons but allowed the calculation of a mean SHRIMP age of 523 ± 9 Ma attributed to the magmatic crystallization. Growth of fine oxides by late fluid–rock interactions was responsible for the scattering of AMS. Rock magnetic data indicate they consist mainly of an oxidized magnetite and (titano)hematite. Shape preferred orientation of mafic aggregates measured in granite quarries shows that the pluton preserves a gently dipping magmatic foliation. AMS in some quarries with a well-defined magmatic fabric, however, remains highly dispersed. When AMS mimics the mafic shape fabric, only magnetic foliations share a common orientation. Locally, AMS grounded in coarse Ti-poor magnetite associated with titanite develops a consistent subhorizontal oblate fabric that agrees with tectonic models suggesting that the cupola of the pluton has been exposed by erosion.

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

Similar content being viewed by others

References

  • Archanjo CJ, Bouchez JL, Corsini M, Vauchez A (1994) The Pombal granite pluton: magnetic fabric, emplacement and relationships with the Brasiliano strike-slip setting of NE Brazil (Paraíba State). J Struct Geol 16:323–335. doi:10.1016/0191-8141(94)90038-8

    Article  Google Scholar 

  • Archanjo CJ, Trindade RIF, Bouchez JL, Ernesto M (2002) Granite fabrics and regional-scale partitioning in the Seridó belt (Borborema Province, NE Brazil). Tectonics 21(1):3-1–3-14. doi:10.1029/2000TC001269

    Google Scholar 

  • Bonin B (2007) A-type granites and related rocks: evolution of a concept, problems and prospects. Lithos 97:1–29. doi:10.1016/j.lithos.2006.12.007

    Article  Google Scholar 

  • Bouchez JL (1997) Granite is never isotropic: an introduction to AMS studies of granitic rocks. In: Bouchez JL, Hutton DHW, Stephens WE (eds) Granite: from segregation of melt to emplacement fabrics. Kluwer, Dordrecht, pp 95–112

    Google Scholar 

  • Baumgartner R, Romer RL, Moritz R, Sallet R, Chiaradia M (2006) Columbite-tantalite bearing granitic pegmatites from the Seridó belt, northeastern Brazil: genetic constraints from U-Pb dating and Pb isotopes. Can Mineral 44:69–86. doi:10.2113/gscanmin.44.1.69

    Article  Google Scholar 

  • Corsini M, Lambert de Figueiredo L, Caby R, Féraud G, Ruffet G, Vauchez A (1998) Thermal history of the Borborema Province deduced from 40Ar/39Ar analysis. Tectonophysics 285:103–117. doi:10.1016/S0040-1951(97)00192-3

    Article  Google Scholar 

  • Compston W, Williams IS, Kirschvink JL (1992) Zircon U-Pb ages for the Early Cambrian time-scale. J Geol Soc London 149:171–184. doi:10.1144/gsjgs.149.2.0171

    Article  Google Scholar 

  • Day RM, Fuller M, Schmidt VA (1977) Hysteresis properties of titanomagnetites: grain size and composition dependence. Phys Earth Planet Inter 13:260–267

    Google Scholar 

  • Dunlop DJ (1972) Magnetic mineralogy of unheated and heated red sediments by coercivity spectrum analysis. Geophys J R Astron Soc 27:37–55

    Google Scholar 

  • Dunlop DJ (2002) Theory and application of the Day plot (Mrs/Ms versus Hcr/Hc) 2. Application to data for rocks, sediments and soils. J Geophys Res 107(B3). doi:10.1029/2001JB0000487

  • Ferré EC, Wilson J, Gleizes G (1999) Magnetic susceptibility and AMS of the Bushveld alkaline granites, South Africa. Tectonophysics 307:113–133. doi:10.1016/S0040-1951(99)00122-5

    Article  Google Scholar 

  • Geoffroy L, Olivier P, Rochette P (1997) Structure of a hypovolcanic acid complex inferred from magnetic susceptibility anisotropy measurements: the Western Red Hills granites (Skye, Scotland, Thulean Igneous Province). Bull Volc 59:147–159. doi:10.1007/s004450050182

    Article  Google Scholar 

  • Goraieb PSS, Abreu FAM, Corrêa JAM, Moura CAV (1988) Relações estratigráficas entre o granito Meruoca e a sequência Ubajara-Jaibaras. XXXV Congr Bras Geol 6:2678–2688

    Google Scholar 

  • Grégoire V, Darrozes J, Gaillot P, Nédélec A (1998) Magnetite grain shape fabric and distribution anisotropy vs rock magnetic fabric: a three-dimensional case study. J Struct Geol 20:937–944. doi:10.1016/S0191-8141(98)00022-4

    Article  Google Scholar 

  • Jelinek V (1978) Statistical processing of magnetic susceptibility measured in groups of specimens. Stud Geophys Geod 22:50–62. doi:10.1007/BF01613632

    Article  Google Scholar 

  • Just J, Kontny A, Wall H, Hirt AM, Martin-Hernandez F (2004) Development of magmatic fabrics during hydrothermal alteration in the Soultz-sous-Forêts granite from the EPS-1 borehole, Upper Rhine Graben. In: Martin-Hernandez F, Luneburg CM, Aubourg C, Jackson M (eds) Magnetic fabric: methods and applications. Geol Soc Lond Spec Publ 238:509–526

    Article  Google Scholar 

  • Lapointe P, Morris WA, Harding KL (1986) Interpretation of magnetic susceptibility–a new approach to geophysical evaluation of the degree of rock alteration. Can J Earth Sci 23:393–401

    Article  Google Scholar 

  • Launeau P, Robin PY (1996) Fabric analysis using the intercept method. Tectonophysics 267:91–119. doi:10.1016/S0040-1951(96)00091-1

    Article  Google Scholar 

  • Launeau P (2004) Mise en évidence des écoulements magmatiques par analyse d’image 2-D des distributions 3-D d’orientations préférentielles de formes. Bull Soc Geol Fr 175(4):331–350. doi:10.2113/175.4.331

    Article  Google Scholar 

  • Launeau P, Robin PY (2005) Determination of fabric and strain ellipsoids from measured sectional ellipses—implementations and applications. J Struct Geol 27:2223–2233. doi:10.1016/j.jsg.2005.08.003

    Article  Google Scholar 

  • Ludwig KR (2001) User’s manual for Isoplot/Ex Version 2.49 A geochronological toolkit for Microsoft Excel. Berkeley Geochronological Center, Spec Publ 1a, 55p

  • Moskowitz BM, Jackson M, Kissel C (1998) Low-temperature magnetic behavior of titanomagnetites. Earth Planet Sci Lett 157:141–149. doi:10.1016/S0012-821X(98)00033-8

    Article  Google Scholar 

  • Muxworthy AR (1999) Low-temperature susceptibility and hysteresis of magnetite. Earth Planet Sci Lett 169:51–58. doi:10.1016/S0012-821X(99)00067-9

    Article  Google Scholar 

  • Nagata T (1967) Identification of magnetic minerals in rocks using methods based on their magnetic properties. In: Collinson DW, Creer KM, Runcorn SK (eds) Methods in paleomagnetism. Developments in solid earth geophysics, vol 3, 609p, Elsevier, Amsterdam

  • Oliveira DC (2001) Reavaliação da evolução tectono-magmática do Graben de Jaibaras (nordeste do Brasil). Acta Geol Hisp 36(1–2):53–95

    Google Scholar 

  • Oliveira DC, Mohriak WU (2003) Jaibaras trough: an important element in the early tectonic evolution of the Parnaíba interior sag basin, Northern Brazil. Mar Pet Geol 20:351–383. doi:10.1016/S0264-8172(03)00044-8

    Article  Google Scholar 

  • Özdemir O, Dunlop DJ (1993) The effect of oxidation on the Verwey transition in magnetite. Geophys Res Lett 20:1671–1674. doi:10.1029/93GL01483

    Article  Google Scholar 

  • Potter DK, Stephenson A (1988) Single-domain particles in rocks and magnetic fabric analysis. Geophys Res Lett 15:1097–1100. doi:10.1029/GL015i010p01097

    Article  Google Scholar 

  • Parsons I (1978) Feldspars and fluids in cooling plutons. Min Mag (Lond) 42:1–17. doi:10.1180/minmag.1978.042.321.01

    Article  Google Scholar 

  • Price JD, Hogan JP, Gilbert MC, Payne JD (1998) Surface and near-surface investigation of the alteration of the Mount Scott Granite and geometry of the Sandy Creek gabbro pluton, Hale Spring area, Wichita Mountains Oklahoma. In: Hogan JP, Gilbert MC (eds) Basement tectonics. Kluwer, Dordrecht, pp 79–122

    Google Scholar 

  • Putnis A, Heinrichs R, Putnis CV, Golla-Schindler U, Collins LG (2007) Hematite in porous red-clouded feldspars: evidence of large-scale crustal fluid-rock interaction. Lithos 95:10–18. doi:10.1016/j.lithos.2006.07.004

    Article  Google Scholar 

  • Robin PY, Jowett EC (1986) Computerized density countoring and statistical evaluation of orientation data using counting circles and continuous weighting functions. Tectonophysics 121:207–223. doi:10.1016/0040-1951(86)90044-2

    Article  Google Scholar 

  • Robin PY (2002) Determination of fabric and strain ellipsoids from measured sectional ellipses—theory. J Struct Geol 24:531–544. doi:10.1016/S0191-8141(01)00081-5

    Article  Google Scholar 

  • Santos TJS, Fetter A, Hackspacher PC, Van Schmus WR, Nogueira Neto JA (2008) Neoproterozoic tectonic and magmatic episodes in the NW sector of Borborema Province, NE Brazil, during assembly of Western Gondwana. J S Am Earth Sci 25:271–284. doi:10.1016/j.jsames.2007.05.006

    Article  Google Scholar 

  • Sial AN, Figueiredo MCH, Long LE (1981) Rare-earth element geochemistry of the Meruoca and Mucambo plutons, Ceará, northeast Brazil. Chem Geol 31:271–283. doi:10.1016/0009-2541(80)90090-X

    Article  Google Scholar 

  • Sial AN, Long LE (1987) Mineral chemistry and stable isotope geochemistry of the Cambrian Meruoca and Mucambo plutons, Ceará, northeast Brazil. International symposium on granites and associated mineralizations (ISGAM), Salvador, Brazil, pp 185–188

  • Sylvester PJ (1989) Post-collisional alkaline granites. J Geol 97:261–280

    Article  Google Scholar 

  • Taylor HP Jr (1977) Water/rock interactions and the origin of H2O in granitic batholiths. J Geol Soc London 133:509–558. doi:10.1144/gsjgs.133.6.0509

    Article  Google Scholar 

  • Tera F, Wasserburg GJ (1972) U-Th-Pb systematics in three Apollo 14 basalts and the problem of initial Pb in lunar rocks. Earth Planet Sci Lett 36:359–362

    Google Scholar 

  • Trindade RIF, Bouchez JL, Bolle O, Nédélec A, Peschler A, Poitrasson F (2001) Secondary fabrics revealed by remanence anisotropy: methodological study and examples from plutonic rocks. Geophys J Int 147:310–318. doi:10.1046/j.0956-540x.2001.01529.x

    Article  Google Scholar 

  • Vernon RH (2000) Review of microstructural evidence of magmatic and solid-state flow. Electron Geosci 5:1–23

    Google Scholar 

Download references

Acknowledgments

This work was funded by the Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP, grant 04/08614-9) and Pró-Reitoria de Pesquisa (USP–Projeto I). We thank Jezimael Avelino da Silva for assisting the fieldwork in Meruoca and Bernard Henry and an anonymous referee for their suggestions and constructive reviews.

Author information

Authors and Affiliations

  1. Instituto de Geociências, USP, Rua do Lago 562, São Paulo, SP, 05508-080, Brazil

    Carlos J. Archanjo & Maria Helena B. M. Hollanda

  2. Laboratoire de Geodynamique et Planétologie, Université de Nantes, 44322, Nantes, France

    Patrick Launeau

  3. Universidade Federal do Rio G. Norte, CCET/DFTE, Natal, 59072-970, Brazil

    José Wilson P. Macedo

  4. Chinese Academy of Geological Science, Beijing University, Beijing, China

    Dunyi Liu

Authors
  1. Carlos J. Archanjo
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Patrick Launeau
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Maria Helena B. M. Hollanda
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. José Wilson P. Macedo
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Dunyi Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Carlos J. Archanjo.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Archanjo, C.J., Launeau, P., Hollanda, M.H.B.M. et al. Scattering of magnetic fabrics in the Cambrian alkaline granite of Meruoca (Ceará state, northeastern Brazil). Int J Earth Sci (Geol Rundsch) 98, 1793–1807 (2009). https://doi.org/10.1007/s00531-008-0342-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00531-008-0342-z

Keywords

Search

Navigation