INTRODUCTION 

 Subject and Purpose 



This report presents the results of a sediment strength investigation 

 conducted on core samples from 18 locations in the southwest Pacific 

 and eastern Indian Oceans. The investigation was accomplished in two 

 phases. The initial phase involved a series of shipboard vane shear 

 tests, while the latter phase included the laboratory determination of 

 sediment index properties and the correlation of these index properties 

 to sediment vane shear strength. The latter stage also considered 

 variations of sediment strength and index properties with respect to 

 the depositional environment. 



The contents of this report should be of interest to both the marine 

 geologist and the soils engineer. Since sediments from the geographic 

 areas involved in this study have received little attention from a 

 soil mechanics standpoint, the variations in shear strength and index 

 properties presented in the following pages may assist the marine 

 geologist in defining important geologic events of the past. The type 

 and frequency of the defined events such as turbidity currents at 

 a given site, for example, will, it is hoped, indicate the variability 

 of properties surrounding that site. The soils engineer, in turn, may 

 utilize the techniques to perform foundation designs for inexpensive 

 structures to be located at a particular site. If a geologic review 

 finds that conditions are uniform in the area being considered, the 

 engineer may, on a limited basis, extrapolate design information to 

 areas adjacent to the site studied. 



The latter engineering use of the data seems of particular value, 

 since many inexpensive structures, that may be deployed in the future, 

 cannot justify the time and expense associated with a detailed site 

 investigation. However, when required, the soils engineer must still 

 provide safe but cost-effective design recommendations. The information 

 presented in this report will assist the soils engineer in fulfilling 

 these requirements. 



The purpose of this report is, therefore, to present soil shear 

 strength data and index property information for these 18 locations 

 in the southwest Pacific and eastern Indian Oceans. The data are 

 presented with respect to established trends in soil behavior and to 

 pertinent geologic characteristics of the areas. 



