The parabolic shape was developed by Hsu et al. (1987, 1989a, 1989c), Hsu and
Evans (1989), and Silvester and Hsu (1991, 1993) to improve agreement, as compared
with the log spiral, along the down-drift section of a headland-bay beach. This section
is not typically strongly curved distant from the headland, unless it intersects a sediment-
impounding structure or headland. In studying single-headland beaches, the present
authors developed the hyperbolic-tangent shape as described in this paper, which appears
to have advantages over the parabolic shape in ease of application and interpretation of
empirical parameters defining it.
In the course of this investigation, automated shape fitting routines were developed
in the Graphical User Interface of the MatLab (Version 5) language. These convenient
programs are available from the authors upon request.
HEADLAND-BAY DATABASE
A database was developed comprised of 23 beaches each in Spain and in North
America. Data were sought for beaches extending from relatively small-project scale
(hundreds of meters) to regional scale (exceeding tens of kilometers for the case of the
headland bay downdrift of Cape Canaveral). The database and resultant fitting
parameters are summarized in tabular form at the end of this paper. The observed
headland-bay beaches were classified as having one, two, or "1.5" headlands (partial
headland located down drift of the main headland). The database was developed from
nautical charts, project drawings, and aerial photographs, from which the shoreline