Abstract
The reefless tract directly behind the ribbon reefs on the outer shelf off Cooktown supports a luxuriant growth of Halimeda that, during the Holocene, has developed into bioherms. These mounded biodies of unconsolidated sediment have formed banks that vary in height between 2 and 20 m. Combined shallow, high-resolution seismic reflection profiles and side-scan sonar have diferentiated three areas of biohermal complexes behind the ribbon reefs of Cooktown. Observations by SCUBA and submersible plus the sedimentology of the bioherms indicate that they are in situ accumulations. Evidence from dating of cores suggests that the Halimeda bioherms began to grow about 10 000 years B.P. and their growth has continued to the present time, even though their tops are presently restricted to a depth of -20 m. It is suggested that the origin and morphology of the bioherms are related to a specific hydrodynamic phenomenon, involving jets of nutrient-rich, upwelled oceanic water intruding onto the outer shelf via the narrow passes between the ribbon reefs, and forming eddies behind the ribbons.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Andrews JC, Gentien P (1982) Upwelling as a source of nutrients for the Great Barrier Reef ecosystems: a solution of Darwin's question? Mar Ecol Prog Ser 8:257–269
Davies PJ, Hughes H (1983) High-energy reef and terrigenous sedimentation, Boulder Reef, Great Barrier Reef. BMR J Aust Geol Geophys 8:201–209
Davies PJ, Marshall JF (1985) Halimeda bioherms-low energy reefs, nothern Great Barrier Reef. Proc 5th Int Coral Reef Symp 5:1–7
Davies PJ, Marshall JF, Hopley D (1985) Relations between sea level and reef growth in the central and northern Great Barrier Reef. Proc 5th Int Coral Reef Symp 3:95–103
Drew EA, Abel KM (1983) Growth of Halimeda in reefal and inter-reefal environments. In: Baker JT, Carter RM, Sammarco PW, Stark, KP (eds) Proc Great Barrier Reef Conf. JCU Press, Townsville, pp 299–304
Drew EA, Abel KM (1985) Biology, sedimentology and geography of the vast inter-reefal Halimeda meadows within the Great Barrier Reef province. Proc 5th Int Coral Reef Symp 5:15–20
Kinsey DW, Davies PJ (1979) Effects of elevated nitrogen and phosphorus on coral reef growth. Limnol Oceanogr 24:935–940
Marshall JF, Davies PJ (1985) Late Quaternary sedimentation on a rimmed continental shelf: northern Great Barrier Reef. In: Recent sediments in eastern Australia-marine through terrestrial. Geol Soc Aust Abst 13:20–21
Maxwell WGH (1968) Atlas of the Great Barrier Reef. Elsevier, Amsterdam
Maxwell WGH (1973) Sediments of the Great Barrier Reef province. In: Jones OA, Endean R (eds) Biology and geology of coral reefs, vol 1: geology 1. Academic Press, New York, pp 299–345
Orme GR (1983) Shallow structure and lithofacies of the northern Great Barrier Reef. In: Baker JT, Carter RM, Sammarco PW, Stark KP (eds) Proc Great Barrier Reef Conf. JCU Press, Townsville, pp 135–142
Orme GR (1985) The sedimentological importance of Halimeda in the development of back reef lithofacies, northern Great Barrier Reef (Australia). Proc 5th Int Coral Reef Symp 5:31–37
Orme GR, Flood PG, Sargent GEG (1978) Sedimentation trends in the lee of outer (ribbon) reefs, northern region of the Great Barrier Reef province. Philos Trans R Soc London Ser A 291:85–99
Phipps CVG, Davies PJ, Hopley D (1985) The morphology of Halimeda banks behind the Great Barrier Reef east of Cooktown, Qld. Proc 5th Int Coral Reef Symp 5:27–30
Wolanski E (1986) Water circulation in a topographically complex environment. In: Van de Kreeke J (ed) Dynamics of Shallow Estuaries and Bays. Springer, Berlin Heidelberg New York, pp 154–167
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Marshall, J.F., Davies, P.J. Halimeda bioherms of the northern Great Barrier Reef. Coral Reefs 6, 139–148 (1988). https://doi.org/10.1007/BF00302010
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00302010