1887
Volume 17, Issue 3
  • E-ISSN: 1365-2117

Abstract

Abstract

We investigate the controls on the architecture of coarse‐grained delta progradational units (PUs) in the Pliocene Loreto basin (Baja California Sur, Mexico), a half‐graben located on the western margin of the Gulf of California. Dorsey (1997b) argued that delta progradation and transgression cycles in the basin were driven by episodic fault‐controlled subsidence along the basin‐bounding Loreto fault. Here we test this hypothesis by a detailed analysis of the sedimentary architecture of 11 exceptionally well‐exposed, vertically arranged fluvio‐deltaic PUs, each of which shows lateral facies transition from proximal alluvial facies palaeo‐seaward into distal pro‐delta facies. Of these 11 PUs, seven exhibit a lateral transition from a shoal water to Gilbert‐delta facies associations as they are traced palaeo‐seaward. This transition is characterised by down‐transport development of foresets, which grow in height up to 35 m. Foreset units thicken in a basinward direction, with initially an oblique topset–foreset geometry that becomes increasingly sigmoidal. Each delta is capped by a shell bed that records drowning of the delta top. This systematic transition in delta architecture records increasing water depth through time during individual episodes of progradation. A mechanism that explains this transition is an accelerating rate of fault‐controlled subsidence during each PU. During episodes of low slip rate, shoal‐water deltas prograde across the submerged topography of the underlying delta unit. As displacement rate accelerates, increasing bathymetry at the delta front leads to steepening of foresets and initiation of Gilbert deltas. Subsequent delta drowning results from sediment starvation at the shoreline at high slip rates because of sediment trapping upstream. The observed delta architecture suggests that the long‐term (>100 kyr) history of slip on the Loreto fault was characterised by repetitive episodes of accelerating displacement accumulation. Such episodic fault behaviour is most likely to be because of variations in temporal and spatial strain partitioning between the Loreto fault and other faults in the Gulf of California. A physical explanation for the acceleration phenomenon involves evolving frictional properties on the episodically active Loreto fault.

Loading

Article metrics loading...

/content/journals/10.1111/j.1365-2117.2005.00273.x
2005-08-22
2020-03-29
Loading full text...

Full text loading...

References

  1. Abbott, S.T. (1997) Mid‐cycle condensed shell beds from mid‐Pleistocene cyclotherms, New Zealand: implications for mid-cycle sequence architecture. Sedimentology, 44, 805–824.
    [Google Scholar]
  2. Allen, P.A. & Densmore, A.L. (2000) Sediment flux from an uplifting fault block. Basin Res., 12, 367–380.
    [Google Scholar]
  3. Andrews, E.D. (1984) Bed‐material entrainments and hydraulic geometry of gravel‐bed rivers in Colorado. GSA Bull., 95, 371–378.
    [Google Scholar]
  4. Burns, N., Heller, P.L., Marzo, M. & Paola, C. (1997) Fluvial response in a sequence stratigraphic framework: example from the Montserrat fan delta, Spain. J. Sedimen. Res., 67, 311–321.
    [Google Scholar]
  5. Church, M. & Rood, K. (1983) Catalogue of Alluvial River Channel Regime Data. Department of Geography, Vancouver, BC.
    [Google Scholar]
  6. Colella, A. (1988a) Fault‐controlled marine Gilbert‐type fan deltas. Geology, 16, 1021–1034.
    [Google Scholar]
  7. Colella, A. (1988b) Pliocene–Holocene fan deltas and braid deltas in the Crati Basin, southern Italy: a consequence of varying tectonic conditions. In: Fan Deltas: Sedimentology and Tectonic Setting (Ed. by W.Nemec & R.J.Steel ), pp. 50–74. Blackie, London.
    [Google Scholar]
  8. Colella, A., De boer, P.L. & Nio, D. (1987) Sedimentology of a marine intrmontane Pleistocene Gilbert‐type fan‐delta complex in the Crati Basin, Calabria, southern Italy. Sedimentology, 34, 721–736.
    [Google Scholar]
  9. Colella, A., De boer, P. & Nio, S.D. (1997) Sedimentology of a marine intermontane Pleistocene Gilbert‐type fan‐delta complex in the Crati Basin, Calabria, S. Italy. Sedimentology, 34, 721–736.
    [Google Scholar]
  10. Cowie, P.A. (1998) A healing‐reloading feedback control on the growth rate of seismogenic faults. J. Struct. Geol., 20, 1075–1087.
    [Google Scholar]
  11. Dart, C., Collier, R., Gawthorpe, R., Keller, J. & Nichols, G. (1994) Sequence stratigraphy of Pliocene–Quaternary synrift Gilbert‐type fan deltas, northern Peloponnesos, Greece. Mar. Petrol.Geol., 11, 607–614.
    [Google Scholar]
  12. Dorsey, R.J. & Kidwell, S.M. (1999) Mixed carbonate‐siliciclastic sedimentation on a tectonically active margin: example from the Pliocene of Baja California Sur, Mexico. Geology, 27, 935–938.
    [Google Scholar]
  13. Dorsey, R.J., Stone, K.A. & Umhoefer, P.J. (1997a) Stratigraphy, sedimentology, and tectonic development of the south‐eastern Pliocene Loreto Basin, Baja California Sur, Mexico. GSA Spec. Pap., 318, 83–109.
    [Google Scholar]
  14. Dorsey, R.J. & Umhoefer, P.J. (2000) Tectonic and eustatic controls on sequence stratigraphy of the Pliocene Loreto basin, Baja California Sur, Mexico. GSA Bull., 112, 177–199.
    [Google Scholar]
  15. Dorsey, R.J., Umhoefer, P.J. & Falk, P.D. (1997b) Earthquake clustering inferred from Pliocene Gilbert‐type fan deltas in the Loreto basin, Baja California Sur, Mexico. Geology, 25, 679–682.
    [Google Scholar]
  16. Dorsey, R.J., Umhoefer, P.J. & Renne, P.R. (1995) Rapid subsidence and stacked Gilbert‐type fan deltas, Pliocene Loreto basin, Baja California Sur, Mexico. Sediment. Geol., 98, 181–204.
    [Google Scholar]
  17. Ethridge, F. & Wescott, W. (1984) Tectonic setting, recognition and hydrocarbon potential of fan‐delta deposits. Canad. Soc. Petrol. Geol. Mem., 10, 217–236.
    [Google Scholar]
  18. Falk, P.D. (1996) Sedimentology, stratigraphy, and Gilbert‐delta sedimentation in the southern Pliocene Loreto basin, Baja California Sur, Mexico. Masters Thesis, University of Oregon.
  19. Falk, P.D. & Dorsey, R.J. (1998) Rapid development of gravelly high‐density turbidity currents in marine Gilbert‐type fan deltas, Loreto basin, Baja California Sur, Mexico. Sedimentology, 45, 331–349.
    [Google Scholar]
  20. Gawthorpe, R., Fraser, A. & Collier, R. (1994) Sequence stratigraphy in active extensional basins: implications for the interpretation of ancient basin fills. Mar. Petrol. Geol., 11, 642–658.
    [Google Scholar]
  21. Gilbert, G.K. (1885) The topographic features of lake shores. US Geol. Survey, 69–123.
    [Google Scholar]
  22. Gupta, A.A. & Scholz, C.H. (2000) Fault interactions and seismic hazard. J. Geodyn., 29, 459–467.
    [Google Scholar]
  23. Gupta, S., Underhill, J.R., Sharp, I. & Gawthorpe, R. (1999) Role of fault interactions in controlling synrift sediment dispersal patterns: Miocene Abu Alaqa Group, Suez Rift, Sinai, Egypt. Basin Res., 11, 167–190.
    [Google Scholar]
  24. Heller, P.L., Dueker, K. & Mcmillan, M.E. (2003) Post‐Palaeozoic alluvial gravel transport as evidence of contintental tilting in the U.S. Cordillera. GSA Bull., 115, 1122–1132.
    [Google Scholar]
  25. Kidwell, S.M. (1989) Stratigraphic condensation of marine transgressive records: origin of major shell deposits in the Miocene of Maryland. Geology, 97, 1–24.
    [Google Scholar]
  26. King, G.C.P. & Cocco, M. (2001) Fault interaction by elastic stress changes: new clues from earthquake sequences. Adv. Geophys., 44, 1–38.
    [Google Scholar]
  27. Leeder, M., Harris, T. & Kirkby, M.J. (1998) Sediment supply and climate change: implications for basin stratigraphy. Basin Res., 10, 7–18.
    [Google Scholar]
  28. Lewis, C. & Stock, J.M. (1998) Late Miocene to recent transtensional tectonics in the Sierra San Fermin, northeastern Baja California, Mexico. J. Struct. Geol., 20, 1043–1063.
    [Google Scholar]
  29. Lisiecki, L.E. & Raymo, M.E. (2005) A Plio–Pleistocene stack of 57 globally distributed benthic δ18O records. Paleoceanography, 20, PA1003, doi: 10.1029/2004PA001071.
    [Google Scholar]
  30. Lonsdale, P. (1989) Geology and tectonic history of the Gulf of California. In: Geology of North America, N (Ed. by E.L.e.a.Winterer ), pp. 499–521. Geological Society of America, Boulder, CO.
    [Google Scholar]
  31. Lowe, D.R. (1976) Grain flow and grain flow deposits. J. Sediment. Petrol., 46, 188–199.
    [Google Scholar]
  32. Lowe, D.R. (1982) Sediment gravity flows: II. Depositional models with special reference to the deposits of high-density turbidity currents. J. Sediment. Petrol., 52, 279–297.
    [Google Scholar]
  33. Marr, J.G., Swenson, J.B., Paola, C. & Voller, V.R. (2000) A 2 diffusion model of fluvial stratigraphy in closed depositional basins. Basin Res., 12, 381–398.
    [Google Scholar]
  34. McLean (1989) Reconnaissance geological map of the Loreto and part of the San Javier quadrangles. Baja California sure, Mexico, USGS.
    [Google Scholar]
  35. Milankovitch, M. (1930) Mathematische Kilmalehre and Austronomische Theorie der Klimaschwankungen Gebruder. Borntreger, Berlin, 176pp.
    [Google Scholar]
  36. Mortimer, E. (2004) Tectonic controls on the growth of coarse‐grained delta clinoforms in the Pliocene Loreto Basin, Baja California Sur, Mexico. Doctorate Thesis, University of Edinburgh, Edinburgh, Scotland.
  37. Mulder, T. & Alexander, J. (2001) The physical character of subaqueous sedimentary density flows and their deposits. Sedimentology, 48, 269–299.
    [Google Scholar]
  38. Naish, T.R., Kamp, P.J.J. & Pillans, B. (1997) Recurring global sea‐level changes recorded in shelf deposits near the G/M polarity transition, Wanganui basin, New Zealand: implications for redefining the Pliocene-Pleistocene boundary. Quat. Int., 40, 61–71.
    [Google Scholar]
  39. Nemec, W. (1990) Aspects of sediment movement on steep delta slopes. In: Coarse Grained Deltas (Ed. by A.Colella & D.B.Prior ), IAS Spe. Publ , 10, 29–73.
    [Google Scholar]
  40. Nemec, W. & Steel, R.J. (1984) Alluvial and coastal conglomerates: their significant features and some comments on gravelly mass‐flow deposits. In: Sedimentology of Gravels and Conglomerates (Ed. by E.H.Koster & R.J.Steel ), Memoir , 10, 1–31.
    [Google Scholar]
  41. Orpin, G.J. & Reading, H.G. (1993) Variability of deltaic processes in terms of sediment supply, with particular emphasis on grain size. Sedimentology, 43, 927–945.
    [Google Scholar]
  42. Paola, C. & Mohrig, D. (1996) Palaeohydraulics revisited: palaeoslope estimation in coarse-grained braided rivers. Basin Res., 8, 73–90.
    [Google Scholar]
  43. Postma, G. (1990) Depositional architectures and facies of river and fan deltas: a synthesis. In: Coarse Grained Deltas (Ed. by A.Colella & D.B.Prior ), IAS Spec. Publ. , 10, 13–27.
    [Google Scholar]
  44. Postma, G. (1995) Sea‐Level related architectural trends in coarse‐grained delta complexes. Sedimen. Geol., 98, 3–12.
    [Google Scholar]
  45. Postma, G. & Roep, T.B. (1985) Resedimented conglomerates in the bottomsets of Gilbert‐type gravel deltas. J. Sediment. Petrol., 55, 874–885.
    [Google Scholar]
  46. Raymo, M.E., Ganley, K., Carter, S., Oppo, D.W. & Mcmanus, J. (1998) Millennial‐scale climate instability during the early Pleistocene epoch. Nature, 392, 71–98.
    [Google Scholar]
  47. Scholz, C.H. (2002) Mechanics, Earthquakes and Faulting. Cambridge University Press, Cambridge.
    [Google Scholar]
  48. Sohn, Y.K. (1997) On traction carpet sedimentation. Sediment. Geol., 67, 502–509.
    [Google Scholar]
  49. Sohn, Y.K., Kim, S.B., Hwang, I.G., Bahk, J.J., Choe, M.Y. & Chough, S.K. (1997) Characteristics and depositional processes of large‐scale gravelly Gilbert‐type foresets in the Miocene Doumsan fan delta, Pohang Basin, SE Korea. J. Sediment. Res., 67, 130–141.
    [Google Scholar]
  50. Steckler, M.S., Mountain, G.S., Miller, K.G. & Christie‐Blick, N. (1999) Reconstruction of Tertiary progradation and clinoform development on the New Jersey passive margin by 2‐D backstripping. Mar. Geol., 154, 399–411.
    [Google Scholar]
  51. Swenson, J.B., Voller, V.R., Paola, C., Parker, G. & Marr, J.G. (2000) Fluvio‐detlaic sedimentation: a generalised Stefan problem. Eur. J. Appl. Math., 11, 433–452.
    [Google Scholar]
  52. Umhoefer, P.J. & Dorsey, R.J. (1997) Translation of terranes: lessons from Baja California, Mexico. Geology, 25, 1007–1010.
    [Google Scholar]
  53. Umhoefer, P.J., Dorsey, R.J. & Renne, P.R. (1994) Tectonics of the Pliocene Loreto basin, Baja California Sur, Mexico, and evolution of the Gulf of California. Geology, 22, 649–652.
    [Google Scholar]
  54. Umhoefer, P.J. & Stone, K.A. (1996) Description and kinematics of the SE Loreto basin fault array, Baja California Sur, Mexico: a positive field test of oblique-rift models. J. Struct. Geol., 18, 595–614.
    [Google Scholar]
  55. Willemse, E.J.M., Pollard, D.D. & Aydin, A. (1996) 3‐dimensional. analyses of slip distributions on normal fault arrays with consequences for fault scaling. J. Struct. Geol., 18, 295–309.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.1111/j.1365-2117.2005.00273.x
Loading
/content/journals/10.1111/j.1365-2117.2005.00273.x
Loading

Data & Media loading...

  • Article Type: Research Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error