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sediment that accumulated on the seaward (basin)
side of the Clino location. It is proposed that this
fracturing formed during a period of tectonic
quiescence on Great Bahama Bank and is thus
essentially non-tectonic in origin.
The Clino fracture data support a non-tectonic
mechanism for the formation of macroscopic
fractures. The combination of early diagenesis
(cementation) and the subsequent load emplace-
ment by the prograding platform margin have
produced very early fracturing in the burial history
of the platform. These fractures (at least for their
early burial history) have distinct geophysical log
signatures, and have largely remained opened and
largely unfi lled (except for some celestite infi ll).
The original porosity, or later re-opened fracture
porosity, may act as major fl uid-fl ow pathways
within the platform margin slope. Those pathways
may be conduits for the upward movement of burial
fl uids and focus diagenetic alteration associated
with those burial fl uids. In the deeper subsurface,
associated fracture permeability may enhance
vertical and lateral fl uid fl ow.
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ACKNOWLEDGEMENTS
We fi rst and foremost want to thank Robert
Ginsburg for his longstanding drive and lead-
ership to make the Bahamas Drilling Project a
reality. The US National Science Foundation
supported this project, both the drilling and
subsequent analyses (OCE 8917295 and OCE
9104294). We also thank the Industrial Associates
of the Comparative Sedimentology Laboratory
for providing funds for core collection and (con-
tinued) analysis. The Donors to the American
Chemical Society-Petroleum Research Fund
(25818-AC8) supported DFM. The work of Jeroen
Kenter, Peter Swart and Leslie Melim provided
the framework critical to interpreting the Clino
fractures, and we thank them for their input.
We are grateful to David Olgaard for conducting
the uniaxial deformation experiments on Clino
core samples while at ETH-Zurich. Prof. Harry
Elderfi eld's laboratory at University of Cambridge
kindly provided the Sr data on the celestite in
collaboration with Peter Swart (University of
Miami). We thank Al Hine for suggesting a pos-
sible role of early fracture on the collapse of
platform margins. Art Saller and Taury Smith
provided thoughtful review and constructive
comments on this manuscript.
