Coral Extension Rate Analysis Using Computed Axial Tomography
Abstract
Biological and geological studies of coral reefs often rely on measured
Scleractinian coral skeletal extension rates. Ideally, corallites are oriented parallel to a
coral core’s longitudinal axis and perpendicular to its annual high-density growth bands.
To examine corallite orientations, we use high-resolution computed axial tomography to
image ten short Montastrea faveolata cores from the northwest Gulf of Mexico. This
non-destructive method enable the comparison of extension rates determined several
ways: 1) across a single slice or slab X-ray image, 2) between 0.6 mm slice and 8.4mm
slab X-ray images, and 3) among slice/slab orientated at varied angles relative to a coral
core’s longitudinal axis. Additionally, the true three-dimensional extension rate of
individual corallites is determined and compared to the extension rate apparent on a twodimensional
slice/slab. Results suggest minimal significant differences between all
methods, confirming the conventional extension rate methodology is suitable for studies
if the core’s longitudinal axis is in approximate alignment with the growth axis of the
corallites. Determination of three-dimensional corallite growth patterns leads to
improved understanding of the development of the coral colony.
Citation
Yudelman, Eleanor Ann (2014). Coral Extension Rate Analysis Using Computed Axial Tomography. Master's thesis, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /152491.