Growth and Burrow-Transformation of Carbonate Banks: Comparison of Modern Skeletal Banks of South Florida and Pennsylvanian Phylloid Banks of South-Eastern Kansas, USA
- C. L. V. Monty,
- D. W. J. Bosence,
- P. H. Bridges and
- B. R. Pratt
Published Online: 14 APR 2009
Copyright © 1995 The International Association of Sedimentologists
Carbonate Mud-Mounds: Their Origin and Evolution
How to Cite
Tedesco, L. P. and Wanless, H. R. (1995) Growth and Burrow-Transformation of Carbonate Banks: Comparison of Modern Skeletal Banks of South Florida and Pennsylvanian Phylloid Banks of South-Eastern Kansas, USA, in Carbonate Mud-Mounds: Their Origin and Evolution (eds C. L. V. Monty, D. W. J. Bosence, P. H. Bridges and B. R. Pratt), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304114.ch18
- Published Online: 14 APR 2009
- Published Print: 17 JUL 1995
Print ISBN: 9780865429338
Online ISBN: 9781444304114
- growth and burrow transformation of carbonate banks;
- Safety Valve Skeletal Bar Belt;
- Mollusc wackestone to packstone with lithoclasts;
- climatic energy levels- gentle trade winds, winter cold fronts, and tropical storms;
- distinct and indistinct burrow-fill fabrics;
- catastrophic sedimentation within phylloid banks
The fabric and facies of both modern and ancient carbonate skeletal banks have been difficult to interpret because they contain characteristics that appear equivocal with respect to reconstruction of growth history, palaeoenvironment and energy setting. Commonly, the core facies of both modern and ancient skeletal banks contain unabraded but disarticulated skeletal material in a wackestone to packstone matrix, lack pronounced or diagnostic stratification, and possess a mottled fabric containing coarser patches and networks of skeletal or intraclastic grainstone to packstone. These are characteristics of facies that have been produced by repetitive excavation and storm infilling of open burrow systems.
Deep-excavating burrowers create extensive open burrow networks that commonly penetrate to sediment depths in excess of 1–2 m. These subsurface chambers can be catastrophically infilled with coarse to fine surficial sediment. Repetitive excavation and infilling of subsurface burrow systems can obliterate precursor facies and create the preserved depositional fabrics and facies.
Modern skeletal banks of the Safety Valve Skeletal Bar Belt, Biscayne Bay, south-east Florida are built predominantly by pulses of physically deposited, layered grainstone (on exposed flanks) to mudstone (in the core and on protected flanks). Intense burrowing by excavating organisms and infilling of open burrows by storms between mudstone depositional events, converts layered mudstone into the mottled skeletal packstone that dominates skeletal banks. Evidence of the origin and growth of the bank is masked by this facies transformation.
The fabric (ichnofabric), lithologies and depositional sequence of upper Pennsylvanian phylloid banks are remarkably similar to those of modern skeletal banks that have been largely transformed by marine burrowing. The dominant lithology comprising the studied phylloid bank is a burrow-generated lithology that was deposited initially as a mudstone to phylloid wackestone. Burrow excavation and infilling resulted in the removal of precursor mudstone and phylloid wackestone lithologies and replacement with skeletal grainstone. Remnants of former mudstone to wackestone lithologies are all that remain of the original depositional lithologies in the bulk of the bank. Phylloid wackestone to mudstone with spar-cemented grainstone networks and patches is the dominant lithology within the banks and is a burrow-generated lithology that represents an episodically high energy setting well above storm wave base.
The recognition of burrow-generated lithologies resulting from storm infilling of burrow networks necessitates that these ancient phylloid banks formed above storm wave base. This is in contrast to many previous interpretations.