Hammack, Joseph Leonard, Jr. (1972) Tsunamis  A Model of Their Generation and Propagation. California Institute of Technology , Pasadena, CA. (Unpublished) http://resolver.caltech.edu/CaltechKHR:KHR28

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Abstract
A general solution is presented for water waves generated by an arbitrary movement of the bed (in space and time) in a twodimensional fluid domain with a uniform depth. The integral solution which is developed is based on a linearized approximation to the complete (nonlinear) set of governing equations. The general solution is evaluated for the {specific case of a uniform upthrust or downthrow of a block section of the bed; two timedisplacement histories of the bed movement are considered. An integral solution (based on a linear theory) is also developed for a threedimensional fluid domain of uniform depth for a class of bed movements which are axially symmetric. The integral solution is evaluated for the specific case of a block upthrust or downthrow of a section of the bed, circular in planform, with a timedisplacement history identical to one of the motions used in the twodimensional model. Since the linear solutions are developed from a linearized approximation of the complete nonlinear description of wave behavior, the applicability of these solutions is investigated. Two types of nonlinear effects are found which limit the applicability of the linear theory: (1) large nonlinear effects which occur in the region of generation during the bed movement, and (2) the gradual growth of nonlinear effects during wave propagation. A model of wave behavior, which includes, in an approximate manner, both linear and nonlinear effects is presented for computing wave profiles after the linear theory has become invalid due to the growth of nonlinearities during wave propagation. An experimental program has been conducted to confirm both the linear model for the twodimensional fluid domain and the strategy suggested for determining wave profiles during propagation after the linear theory becomes invalid. The effect of a more general timedisplacement history of the moving bed than those employed in the theoretical models is also investigated experimentally. The linear theory is found to accurately approximate the wave behavior in the region of generation whenever the total displacement of the bed is much less than the water depth. Curves are developed and confirmed by the experiments which predict gross features of the lead wave propagating from the region of generation once the values of certain nondimensional parameters (which characterize the generation process) are known. For example, the maximum amplitude of the lead wave propagating from the region of generation has been found to never exceed approximately onehalf of the total bed displacement. The gross features of the tsunami resulting from the Alaskan earthquake of 27 March 1964 can be estimated from the results of this study.
Item Type:  Report or Paper (Technical Report) 

Additional Information:  The writer also wishes to thank the California Institute of Technology for financial assistance and for providing a most stimulating environment in which to work. This research was supported by NSF Grants GK2370 and GK24716; experiments were conducted at the W. M. Keck Laboratory of Hydraulics and Water Reasources. 
Group:  W. M. Keck Laboratory of Hydraulics and Water Resources 
Record Number:  CaltechKHR:KHR28 
Persistent URL:  http://resolver.caltech.edu/CaltechKHR:KHR28 
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ID Code:  25989 
Collection:  CaltechKHR 
Deposited By:  Imported from CaltechKHR 
Deposited On:  20 Apr 2005 
Last Modified:  26 Dec 2012 13:51 
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