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Time-averaging and postmortem skeletal survival in benthic fossil assemblages: quantitative comparisons among Holocene environments

Published online by Cambridge University Press:  08 February 2016

Keith H. Meldahl ,
Karl W. Flessa  and
Alan H. Cutler
Keith H. Meldahl
Affiliation:
Department of Geology, Oberlin College, Oberlin, Ohio 44074
Karl W. Flessa
Affiliation:
Department of Geosciences, University of Arizona, Tucson, Arizona 85721
Alan H. Cutler
Affiliation:
Department of Paleobiology, NHB MRC-121 Smithsonian Institution, Washington, D.C. 20560
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Abstract

We used radiocarbon ages on dead Holocene shells of the venerid bivalve Chione spp. to investigate how time-averaging and taphonomy in shallow marine benthic assemblages vary with sedimentary and tectonic setting. We compared shells collected from the sediment surface in five depositional environments from two regions of the Gulf of California, Mexico: Bahía Concepción, a young faulted rift basin with high rates of terrigenous and carbonate sedimentation; and Bahía la Choya, an intertidal system along a sediment-starved shelf. Frequency distributions of shell ages in all environments form a hollow curve, with a mode at young ages and a long tail toward older ages. This pattern suggests that shells are added to the taphonomically active zone (TAZ) at roughly constant rates (via continuous shell deaths), and removed from the TAZ at random, either through destruction or by achieving final burial. Shell half-lives (the amount of time to remove half the shells from the TAZ) provide a comparative measure of time-averaging. Time-averaging varies with sedimentary and tectonic setting. The lowest amounts of time-averaging (shell half-lives of 90 to 165 years) occur in Bahía Concepción, where rapid rates of terrigenous sedimentation (on fan-deltas) and carbonate sedimentation (in pocket bays) bury shells rapidly. Time-averaging is higher in the sediment-starved environments of Bahía la Choya (shell half-lives of 285 to 550 years). The highest amounts of time-averaging occur the inner tidal flats of Bahía la Choya (shell half-life of 550 years). Here the conjunction of low sedimentation rates with low rates of shell destruction (due to periodic tidal emergence) permits shells to persist in the TAZ for very long time spans.

There is no systematic relationship between a shell's age and its taphonomic condition (taphonomic grade) in any environment, probably because of the complex and random nature of burial-exhumation in the TAZ. Age variance tends to increase with increasing taphonomic alteration: highly altered shells range in age from young to several thousand years old, while less altered shells are mostly young. The correspondence between time-averaging and the taphonomic condition of entire shell assemblages is also weak, but might be resolved with further study.

These results provide quantitative data on time-averaging in benthic assemblages as a function of sedimentary and tectonic setting, and suggest some guidelines for facies appropriate for particular studies. Shallow marine rift basins like Bahía Concepción can potentially contain within-horizon fossil assemblages representing time spans of only a few hundred years—time resolution often beyond reach in paleontology. In contrast, sediment-starved shelf habitats like Bahía la Choya are unlikely to yield assemblages with time resolution finer than several thousands of years.

Type
Articles
Information
Paleobiology , Volume 23 , Issue 2 , Spring 1997 , pp. 207 - 229
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Aberhan, M., and Fürsich, F. T. 1991. Paleoecology and paleoenvironments of the Pleistocene deposits of Bahía la Choya (Gulf of California, Sonora, Mexico). In Fürsich, F. T. and Flessa, K. W., eds. Ecology, taphonomy and paleoecology of Recent and Pleistocene molluscan faunas of Bahía la Choya, northern Gulf of California. Zitteliana 18:135–164.Google Scholar
Allison, P., and Briggs, D. E. G. 1991. Taphonomy: releasing the data locked in the fossil record. Plenum, New York.CrossRefGoogle Scholar
Behrensmeyer, A. K. 1982. Time resolution in fluvial vertebrate assemblages. Paleobiology 8:211–227.CrossRefGoogle Scholar
Behrensmeyer, A. K. 1991. Terrestrial vertebrate accumulations. pp. 291–335in Allison and G. Briggs 1991. Taphonomy: releasing the data locked in the fossil record. Plenum, New York.Google Scholar
Behrensmeyer, A. K., and Chapman, R. E. 1993. Models and simulations of time-averaging in terrestrial vertebrate accumulations. pp. 125–149in Kidwell and Behrensmeyer 1993.Google Scholar
Bowman, S. 1990. Radiocarbon dating. University of California Press, Berkeley.Google Scholar
Brandt, D. S. 1989. Taphonomic grades as a classification for fossiliferous assemblages and implications for paleoecology. Palaios 4:303–309.CrossRefGoogle Scholar
Brett, C. E., and Baird, G. C. 1993. Taphonomic approaches to time resolution in stratigraphy: examples from Paleozoic marine mudrocks. pp. 250–274in Kidwell and Behrensmeyer 1993.Google Scholar
Burke, K., Francis, P., and Wells, G. 1990. Importance of the geologic record in understanding global change. Palaeogeography, Palaeoclimatology, Palaeoecology 89:193–204.CrossRefGoogle Scholar
Burnham, R. J. 1993. Time resolution in terrestrial macrofloras: guidelines from modern assemblages. pp. 57–78in Kidwell and Behrensmeyer 1993.Google Scholar
Cummins, H., Powell, E. N., Stanton, R. J. Jr., and Staff, G. 1986. The rate of taphonomic loss in modern benthic habitats: How much of the potentially preservable community is preserved? Palaeogeography, Palaeoclimatology, Palaeoecology 52:291–320.CrossRefGoogle Scholar
Cutler, A. H. 1993. Mathematical models of temporal mixing in the fossil record. pp. 169–187in Kidwell and Behrensmeyer 1993.Google Scholar
Cutler, A. H. 1994. Taphonomic implications of shell surface textures in Bahia la Choya, northern Gulf of California. Palaeogeography, Palaeoclimatology, Palaeoecology 114:219–240.CrossRefGoogle Scholar
Davies, D. J., Powell, E. N., and Stanton, J. R. Jr. 1989. Relative rates of shell dissolution and net sediment accumulation—a commentary: can shell beds form by the gradual accumulation of biogenic debris on the sea floor? Lethaia 22:207–212.CrossRefGoogle Scholar
Davies, D. J., Staff, G. M., Callender, W. R., and Powell, E. N. 1990. Description of a quantitative approach to taphonomy and taphofacies analysis: all dead things are not created equal. In. Miller, W., ed. Paleocommunity temporal dynamics: the long-term development of multispecies assemblages. Paleontological Society Special Publication 5:328–350. University of Tennessee, Knoxville.Google Scholar
Ezcurra, E., and Rodrigues, V. 1986. Rainfall patterns in the Gran Desierto, Sonora, Mexico. Journal of Arid Environments 10:13–28.CrossRefGoogle Scholar
Feige, A., and Fürsich, F. T. 1991. Taphonomy of the Recent molluscs of Bahia la Choya. In Fürsich, F. T. and Flessa, K. W., eds. Ecology, taphonomy and paleoecology of Recent and Pleistocene molluscan faunas of Bahia la Choya, northern Gulf of California. Zitteliana 18:89–134.Google Scholar
Flessa, K. W. 1987. Paleoecology and taphonomy of Recent to Pleistocene intertidal deposits, Gulf of California. Paleontological Society Special Publication 2. University of Tennessee, Knoxville.CrossRefGoogle Scholar
Flessa, K. W. 1993. Time-averaging and temporal resolution in Recent marine shelly faunas. pp. 9–33in Kidwell and Behrensmeyer 1993. Taphonomic approaches to time resolution in fossil assemblages.Google Scholar
Flessa, K. W., and Kowalewski, M. 1994. Shell survival and time-averaging in nearshore and shelf environments: estimates from the radiocarbon literature. Lethaia 27:153–165.CrossRefGoogle Scholar
Flessa, K. W., Cutler, A. H., and Meldahl, K. H. 1993. Time and taphonomy: quantitative estimates of time-averaging and stratigraphic disorder in a shallow marine habitat. Paleobiology 19:266–286.CrossRefGoogle Scholar
Foster, M. S., Riosmena, R., Steller, D. S., and Woelkerling, W. J. In press. Living rhodolith beds in the Gulf of California and their implications for paleoenvironmental interpretation. In Johnson, M. E. and Ledesma-Vasquez, J., eds. Pliocene carbonates and related facies flanking the Gulf of California, Baja California, Mexico. Geological Society of America Special Paper 318. Boulder, Colo.Google Scholar
Fürsich, F. T., and Aberhan, M. 1990. Significance of time-averaging for paleocommunity analysis. Lethaia 23:143–152.CrossRefGoogle Scholar
Fürsich, F. T., and Flessa, K. W. 1987. Taphonomy of tidal flat molluscs in the northern Gulf of California: paleoenvironmental analysis despite the perils of preservation. Palaios 2:543–559.CrossRefGoogle Scholar
Fürsich, F. T. and Flessa, K. W., eds. 1991. Ecology, taphonomy and paleoecology of Recent and Pleistocene molluscan faunas of Bahia la Choya, northern Gulf of California. Zitteliana 18:1–180.Google Scholar
Goodfriend, G. A. 1987. Chronostratigraphic studies of sediments in the Negev Desert, using amino acid epimerization analysis of land snail shells. Quaternary Research 28:374–392.CrossRefGoogle Scholar
Graham, R. W. 1993. Processes of time-averaging in the terrestrial vertebrate record. pp. 102–124in Kidwell and Behrensmeyer 1993. Taphonomic approaches to time resolution in fossil assemblages.Google Scholar
Hallam, A. 1972. Models involving population dynamics. pp. 62–80in Schopf, T. J. M., ed. Models in paleobiology. Freeman, Cooper, San Francisco.Google Scholar
Hartshorne, P., Gillispe, W., and Flessa, K. W. 1987. Population structure of live and dead gastropods from Bahia la Choya. In Flessa, K.W., ed. Paleoecology and taphonomy of Recent to Pleistocene intertidal deposits, Gulf of California. Paleontological Society Special Publication 2:139–149. University of Tennessee, Knoxville.Google Scholar
Hayes, M. L., Johnson, M. E., and Fox, W. T. 1993. Rocky-shore biotic associations and their fossilization potential: Isla Requeson (Baja California Sur, Mexico). Journal of Coastal Research 9:944–957.Google Scholar
Johnson, K. R. 1993. Time resolution and the study of Late Cretaceous and early Tertiary mega floras. pp. 210–227in Kidwell and Behrensmeyer 1993. Taphonomic approaches to time resolution in fossil assemblages.Google Scholar
Kidwell, S. M. 1991. The stratigraphy of shell concentrations. pp. 212–290in Allison and Briggs 1991.Google Scholar
Kidwell, S. M. 1993a. Patterns of time-averaging in the shallow marine fossil record. In pp. 215–300in Kidwell and Behrensmeyer 1993. Taphonomic approaches to time resolution in fossil assemblages.Google Scholar
Kidwell, S. M. 1993b. Taphonomic expressions of sedimentary hiatuses: field observations on bioclastic concentrations and sequence anatomy in low, moderate and high subsidence settings. Geologische Rundschau 82:189–202.CrossRefGoogle Scholar
Kidwell, S. M., and Behrensmeyer, A. K. 1993. Taphonomic approaches to time resolution in fossil assemblages. Paleontological Society Short Courses in Paleontology No. 6. University of Tennessee, Knoxville.CrossRefGoogle Scholar
Kidwell, S. M., and Bosence, D. W. J. 1991. Taphonomy and time-averaging of marine shelly faunas. pp. 115–209in Allison and Briggs 1991.Google Scholar
Leeder, M. R. 1995. Continental rifts and proto-oceanic rift troughs. pp. 119–148In Busby, C.R. and Ingersoll, R.V., eds. Tectonics of sedimentary basins. Blackwell Scientific, Cambridge, Mass.Google Scholar
Leeder, M. R., and Gawthorpe, R. L. 1987. Sedimentary models for extensional tilt-block / half-graben basins. In Coward, M. P., Dewey, J. F., and Handcock, P. L., eds. Continental extensional tectonics. Geological Society Special Publication 28:139–152. Boulder, Colo.CrossRefGoogle Scholar
Martin, R. E. 1993. Time and taphonomy: actualistic evidence for time-averaging of benthic foraminiferal assemblages. pp. 34–56in Kidwell and Behrensmeyer 1993.Google Scholar
Martin, R. E., Wehmiller, J. F., Harris, M. S., and Liddell, W. D. 1996. Comparative taphonomy of bivalves and foraminifera from Holocene tidal flat sediments, Bahia la Choya, Sonora, Mexico (northern Gulf of California): taphonomic grades and temporal resolution. Paleobiology 22:80–90.CrossRefGoogle Scholar
McFall, C. C. 1968. Reconnaissance geology of the Concepción Bay area, Baja California, Mexico. Stanford University Publications in Geological Sciences 10(5):1–25.Google Scholar
Meldahl, K. H. 1987. Sedimentologic and taphonomic implications of biogenic stratification. Palaios 2:350–358.CrossRefGoogle Scholar
Meldahl, K. H. 1990. Sampling, species abundance, and the stratigraphic signature of mass extinction: a test using Holocene tidal flat molluscs. Geology 18:890–893.2.3.CO;2>CrossRefGoogle Scholar
Meldahl, K. H. 1994. Biofacies and taphofacies of a Holocene macrotidal environment: Bahia la Cholla, northern Gulf of California. Ciencias Marinas 20:555–583.CrossRefGoogle Scholar
Meldahl, K. H., Gonzalez-Yajimovich, O., Empedocles, C., Gustafson, C., Motolinia-Hidalgo, M., and Reardon, T. In press. Holocene sediments and molluscan faunas of Bahía Concepción: a modern analog to Neogene rift basins of the Gulf of California. In Johnson, M. E. and Ledesma-Vasquez, J., eds. Pliocene Carbonates and Related Facies Flanking the Gulf of California, Baja California, Mexico. Geological Society of America Special Paper 318. Boulder, Colo.Google Scholar
Neumann, A. C. 1966. Observations of coastal erosion in Bermuda and measurements of boring rates of the sponge Cliona lampa. Limnology and Oceanography 11:92–108.CrossRefGoogle Scholar
Ortlieb, L. 1991. Quaternary shorelines along the northeastern Gulf of California: geochronological data and neotectonic implications: Geological Society of America Special Paper 254:95–120.CrossRefGoogle Scholar
Parsons, K. M., and Brett, C. E. 1991. Taphonomic processes and biases in modern marine environments: an actualistic perspective on fossil assemblage preservation. pp. 22–65in Donovan, S. K., ed. The processes of fossilization. Columbia University Press, New York.Google Scholar
Pearson, G. W., Becker, B., and Qua, F. 1993. High precision 14C measurement of German and Irish oaks to show the natural 14C variations from 7890 to 5000 BC. Radiocarbon 35:93–104.CrossRefGoogle Scholar
Perkins, R. D., and Tsentas, C. J. 1976. Microbial infestations of carbonate substrates planted on the St. Croix shelf, West Indies. Geological Society of America Bulletin 87:1615–1628.2.0.CO;2>CrossRefGoogle Scholar
Powell, E. N., and Davies, D. J. 1990. When is an “old” shell really old? Journal of Geology 98:823–844.CrossRefGoogle Scholar
Powell, E. N., Staff, G., Davies, D. J., and Callendar, W. R. 1989. Macrobenthic death assemblages in modern marine environments: formation, interpretation and application. Critical Reviews in Aquatic Science 1:555–589.Google Scholar
Rogers, R. R. 1993. Systematic patterns of time-averaging in the terrestrial vertebrate record. In Taphonomic approaches to time resolution in fossil assemblages. pp. 228–249in Kidwell and Behrensmeyer 1993.Google Scholar
Seilacher, A. 1973. Biostratinomy: the sedimentology of biologically standardized particles. pp. 159–177in Ginsburg, R. N., ed. Evolving concepts in sedimentology. Johns Hopkins University Press, Baltimore.Google Scholar
Stearley, R. F., and Ekdale, A. A. 1989. Modern marine bioerosion by macroinvertebrates, northern Gulf of California. Palaios 4:453–467.CrossRefGoogle Scholar
Steller, D. L., and Foster, M. S. 1995. Environmental factors influencing the distribution and morphology of rhodoliths in Bahia Concepción. B.C.S., Mexico. Journal of Experimental Marine Biology and Ecology 194:210–212.Google Scholar
Stuiver, M., and Braziunas, T. F. 1993. Modeling atmospheric 14C influences and 14C ages of marine samples to 10,000 BC. Radiocarbon 35:137–189.CrossRefGoogle Scholar
Stuiver, M, and Kra, R. 1986. Calibration issue. 12th International Radiocarbon Conference. Radiocarbon 28:805–1030.Google Scholar
Stuiver, M., Pearson, G. W., and Brazinuas, T. 1986. Radiocarbon age calibration of marine samples back to 9000 cal yr BP. Radiocarbon 28:980–1021.CrossRefGoogle Scholar
Tudhope, A. W., and Risk, M. J. 1985. Rate of dissolution of carbonate sediments by microboring organisms, Davies Reef, Australia. Journal of Sedimentary Petrology 55:440–447.Google Scholar
Walker, K. R., and Bambach, R. K. 1971. The significance of fossil assemblages from fine-grained sediments: time-averaged communities. Geological Society of America Abstracts with Programs 3:783–784.Google Scholar