TABLE OF CONTENTS

 pae

A C K N O W L E D G M E N T S ................................................................................................. iv

L IST O F T A B L E S ............. ........ .. ........................................... .. ...... ....... ix

LIST OF FIGURES ................................. ...... ... ................. .x

ABSTRACT ........ .............. ............. .. ...... .......... .......... xii

CHAPTER

1 GENERAL INTRODUCTION ..................................................... .....................

 Deformation Processes of Subduction Zones......................................................2
 Role of the Decollem ent Zone............................................................ ...........3
 C critical T aper T heory ................................................... ............................. 4
 Role of Fluid Flow at Convergent Margins..................................................6
 Evidence for Fluid Flow and Pressures............... ................................................6
 Basics of Fluid Flow Related to Subduction Zone................. ..............................10
 P erm eab ility ...................................... ............................ ................ 1 1
 Hydrogeologic Modeling........................................................... 12
 Statement of Problem ............. ....... .......... .................. 13

2 A COMPARATIVE STUDY OF PERMEABILITY MEASUREMENTS FROM
 THE SUBDUCTION ZONES OF NORTHERN BARBADOS, COSTA RICA,
 N A N K A I, A N D P E R U .................................................................... ..................... 16

 Introduction..................................... .................................. ........... 16
 B background .............................................................................................................18
 B arbados ............................................................................................. ........18
 C o sta R ic a ...................................................................................................... 1 9
 N a n k a i .......................................................................................2 0
 P e r u ................................................................................................................ 2 2
 Laboratory Perm ability Data..................................................................23
 B arbados ................................................................................................... ....... 24
 N ankai and P eru .............................................................2 5
 C o sta R ic a ...................................................................................................... 2 6
 Permeability-Porosity Relationship .......... ..... ........................ ........... 27
 D description of Statistical M ethods................................. .................. 27