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Tectonic significance of magnetic susceptibility fabrics in Plio-Quaternary mudstones of southwestern foothills, Taiwan

Abstract

Anisotropy of magnetic susceptibility (AMS) was studied in three Plio-Pleistocene turbiditic mudstone sequences accumulated in the foreland basin of southwestern Taiwan. These formations were incorporated in the front units of the collision belt and underwent folding and thrusting during the last 2 Ma. Five types of fabrics were identified from more than 3,000 samples collected in 352 sites, with 251 sites allowing determination of a magnetic lineation. NNE-SSW trends are predominant, minor N-S and NE-SW trends are present. Magnetic lineations are widespread in the lower section where folds are tight, and scarce in the youngest sediments where folds are gentle. The strong correlation between the structural features and the AMS orientations suggests a tectonic origin for most magnetic lineations superimposed on the initial flattening that results from sediment compaction. This is confirmed by tectonic studies based on structural analysis and paleostress tensor reconstructions. The tectonic studies reveal a major WNW-ESE compression, which provide orientations of compressive tectonic regimes consistent for resulting the magnetic lineations. In contrast, the hypothesis of a sedimentary origin can be ruled out in most cases, because the orientations of magnetic lineations and those of depositional fabrics (paleocurrents, sediment supply directions and even slumps) are oblique at a variety of angles. Furthermore, based on magnetostratigraphy, we conclude that this compression culminated about 0.9–1 Ma ago. Earlier minor events, NW-SE and W-E compression, have also been found and we propose that they have occurred in approximately 1 and 2 Ma ago, respectively. Thus, the main cause of AMS trend is thought to be the WNW-ESE Quaternary compression responsible for major folding and thrusting. In addition, the magnetic fabric of tectonic origin is absent, or poorly marked, in formations younger than about 0.9 Ma to the north. However, it is still recognized but decreased after about 0.7 Ma ago to the south. This indicates that the WNW-ESE compression propagated southward between 0.9 and 0.7 Ma ago, consistent with the migration of folding and thrusting during the last Taiwan collision. 527-538

References

  1. Angelier, J., Tectonic analysis of fault slip data sets, J. Geophys. Res., 89(B7), 5835–5848, 1984.

    Article  Google Scholar 

  2. Angelier, J., Inversion of field data in fault tectonics to obtain the regional stress, III. A new rapid direct inversion method by analytical means, Geophys. J. Int., 103, 363–376, 1990.

    Article  Google Scholar 

  3. Angelier, J., E. Barrier, and H. T. Chu, Plate collision and paleostress trajectories in a fold-thrust belt: the Foothills of Taiwan, Tectonophys., 125, 161–178, 1986.

    Article  Google Scholar 

  4. Angelier, J., F. Bergerat, H. T. Chu, and T. Q. Lee, Tectonic-paleomagnetic analyses and the evolution of a curved collision belt: the Hsuehshan Range, northern Taiwan, Tectonophys., 183, 77–96, 1990.

    Article  Google Scholar 

  5. Barrier, E. and J. Angelier, Active collision in eastern Taiwan: the Coastal Range, Tectonophys., 125, 1–3, 39–72, 1986.

    Article  Google Scholar 

  6. Chamley, H., J. Angelier, and L. S. Teng, Tectonic and environmental control of the clay mineral sedimentation in the late Cenozoic orogen of Taiwan, Geodinamica Acta, Paris, 6(2), 135–147, 1993.

    Article  Google Scholar 

  7. Chang, L. S., Definition of the Liushuang Formation, Mem. Geol. Soc. China, 1, 189–192, 1962 (in Chinese).

    Google Scholar 

  8. Chi, W. R., The late Neogene nannobiostratigraphy in the Tainan Foothills region, southern Taiwan, Petrol. Geol. Taiwan, 15, 89–125, 1978.

    Google Scholar 

  9. Chu, H. T., Néotectonique cassante et collision Plio-Quaternaire á Taiwan, Mem. Sc. Terre Univ. P. et M. Curie, Paris, 90-28, 292 pp., 1990.

  10. Déffontaines, B., J. C. Lee, J. Angelier, J. Carvalho, and J. P. Rudant, New geomorphic data on the active Taiwan orogen: a multisource approach, J. Geol. Res., 99(B10), 20243–20266, 1994.

    Article  Google Scholar 

  11. Graham, J. W., Significance of magnetic anisotropy in Appalachian sedimentary rocks, in The Earth Beneath the Continents, edited by J. S. Steinhard et al., pp. 627–648, Geophys. Monogr. 10, AGU, 1966.

  12. Henry, B., Studies of microtectonics, anisotropy of magnetic susceptibility and paleomagnetism of the Permian Dome de Barrot (France): Paleotectonics and paleosedimentological implications, Tectonophys., 17, 61–72, 1973.

    Article  Google Scholar 

  13. Ho, C. S., A synthesis of the geologic evolution of Taiwan, Tectonophys., 125, 1–16, 1986.

    Article  Google Scholar 

  14. Ho, C. S., An Introduction to The Geology of Taiwan: Explanatory Text of the Geologic Map of Taiwan, 2nd edition, 225 pp., Ministry of Economic Affairs, R.O.C., 1988.

    Google Scholar 

  15. Horng, C. S., Magnetic mineralogy and magnetostratigraphic studies of the Tsengwenchi and Erhjenchi sections, southwestern Taiwan, Ph.D. dissertation, Inst. of Oceano., National Taiwan Univ., 323 pp., 1991.

  16. Horng, C. S., J. C. Chen, and T. Q. Lee, Variation in magnetic minerals from two Plio-Pleistocene marine-deposited sections, southwestern Taiwan, J. Geol. Soc. China, 35(4), 323–335, 1992.

    Google Scholar 

  17. Hrouda, F., The strain interpretation of magnetic anisotropy in rocks of the Nizky JesenikMountains (Czechoslovakia), Sbor. Geol. Ved, UG 16, 27–62, 1979.

    Google Scholar 

  18. Hrouda, F. and F. Janak, The changes in shape of the magnetic susceptibility ellipsoid during progressive metamorphism and deformation, Tectonophys., 34, 135–148, 1976.

    Article  Google Scholar 

  19. Hrouda, F., F. Janak, and L. Rejl, Magnetic anisotropy and ductile deformation of rocks in zones of progressive regional metamorphism, Gerl. Beitr. Geophys., 87, 126–134, 1978.

    Google Scholar 

  20. Hu, J. C., Modélisation numérique et analyse tectonique régionale: le cas de Taiwan, Mem. Sc. Terre Univ. P. et M. Curie, Paris, no95-18, 268 pp., 1995 (in French).

  21. Kissel, C., E. Barrier, C. Laj, and T. Q. Lee, Magnetic fabric in “undeformed” marine clays from compressional zones, Tectonics, 5, 769–781, 1986.

    Article  Google Scholar 

  22. Kligfield, R., W. Lowrie, and I. W. D. Dalziel, Magnetic susceptibility as a strain indicator in the Sudbury Basin, Ontario, Tectonophys., 40, 287–308, 1977.

    Article  Google Scholar 

  23. Kligfield, R., W. H. Owens, and W. Lowrie, Magnetic susceptibility anisotropy, strain, and progressive deformation in Permian sediments from the Maritime Alps (France), Earth Planet. Sci. Lett., 55, 181–189, 1982.

    Article  Google Scholar 

  24. Lacombe, O., J. Angelier, and P. Laurent, Les macles de la calcite, marqueurs des compressions récentes dans un orogène actif: l’exemple des calcaires récifaux du sud de Taiwan, C. R. Acad. Sc. Paris, 316(II), 1805–1813, 1993.

    Google Scholar 

  25. Lee, J. C., Structure et déformation active d’un orogène: Taiwan, Mem. Sc. Terre Univ. P. et M. Curie, Paris, no94-17, 328 pp., 1994.

  26. Lee, T. Q., Evolution tectonique et géodynamique neogène et quaternaire de la chaîne côtière de Taiwan: apport du paléomagnètisme, Mem. Sc. Terre Univ. P. et M. Curie, Paris, no89-03, 328 pp., 1989.

  27. Lee, T. Q. and C. S. Horng, Magnetic fabric analysis of the Plio-Pleistocene Tsengwenchi sedimentary rock sequence, southern Taiwan and its tectonic implications, Proc. Geol. Soc. China, 33(4), 373–389, 1990.

    Google Scholar 

  28. Lee, T. Q. and C. S. Horng, Magnetic fabric analysis of late Neogene Hokouchi sedimentary sequence, southern Taiwan and its tectonic implications, J. Geol. Soc. China, 36(1), 1–14, 1993.

    Google Scholar 

  29. Lee, T. Q., C. Kissel, C. Laj, C. S. Horng, and Y. T. Lue, Magnetic fabric analysis of the Plio-Pleistocene sedimentary formations of the Coastal Range of Taiwan, Earth Planet. Sci. Lett., 98, 23–32, 1990.

    Article  Google Scholar 

  30. Lee, T. Q., C. Kissel, E. Barrier, C. Laj, and W. R. Chi, Paleomagnetic evidence for a diachronic clockwise rotation of the Coastal Range, eastern Taiwan, Earth Planet. Sci. Lett., 104, 245–257, 1991a.

    Article  Google Scholar 

  31. Lee, T. Q., J. Angelier, H. T. Chuand, and F. Bergerat, Rotations in the northeastern collision belt of Taiwan: preliminary results from paleomagnetism, Tectonophys., 199, 109–120, 1991b.

    Article  Google Scholar 

  32. Lu, C. Y. and K. J. Hsu, Tectonic evolution of the Taiwan mountain belt, Petrol. Geol. Taiwan, 29, 15–35, 1992.

    Google Scholar 

  33. Lu, C. Y. and J. Malavieille, Oblique convergence, indentation and rotation tectonics in the Taiwan mountain belt: insights from experimental modelling, Earth Planet. Sci. Lett., 121, 477–494, 1994.

    Article  Google Scholar 

  34. Lu, C. Y., J. Angelier, H. T. Chu, and J. C. Lee, Contraction, transcurrent, rotational and extensional, tectonics: a case study in northern Taiwan, Tectonophys., 246, 129–146, 1995.

    Article  Google Scholar 

  35. Lue, Y. T., T. Q. Lee, and Y. Wang, Paleomagnetic study on the collision-related bending of the fold-thrust belt, northern Taiwan, J. Geol. Soc. China, 38(3), 215–227, 1995.

    Google Scholar 

  36. Stach, L. W., Stratigraphic subdivision and correlation of the upper Cenozoic sequence in the foothills region east of Chiayi and Hsinying, Taiwan, China, Proc. Symp. Petrol. Geol. Taiwan, 177–230, 1957.

  37. Suppe, J., Mechanics of mountain building and metamorphism in Taiwan, Mem. Geol. Soc. China, 4, 67–89, 1981.

    Google Scholar 

  38. Teng, L. S., Geotectonic evolution of late Cenozoic arc-continent collision in Taiwan, Tectonophys., 183, 57–76, 1990.

    Article  Google Scholar 

  39. Tsai, Y. B., Seismotectonics of Taiwan, Tectonophys., 125, 17–37, 1986.

    Article  Google Scholar 

  40. Yeh, Y. H., E. Barrier, C. H. Lin, and J. Angelier, Stress tensor analysis in the Taiwan area from focal mechanisms of earthquakes, Tectonophys., 200, 267–280, 1991.

    Article  Google Scholar 

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Lee, TQ., Angelier, J. Tectonic significance of magnetic susceptibility fabrics in Plio-Quaternary mudstones of southwestern foothills, Taiwan. Earth Planet Sp 52, 527–538 (2000). https://doi.org/10.1186/BF03351660

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  • DOI: https://doi.org/10.1186/BF03351660

Keywords

  • Bedding Plane
  • Greigite
  • Magnetic Lineation
  • Tectonic Origin
  • Western Foothill