130 



Robert A. Kehle 



II. — Euolufuon of a reaidaal from a confintd lava field. 



Stages of evolution. 



lielative resistance to erosion. 



Short cycles of erosion during volcanic activity. Infilled lateral 



valleys. 

 Main lateral streams. Beginning of Intermediate cycle. 

 Minor laterals. 



Process of breaching. Cross streams, 

 liesiduals with resistant rocks on one side. 

 Ultimate configuration of residuals. 

 ** Uncovered residuals." 

 Isolation of residuals. 



///. — Evolution of a residual from an exte7isive lava field. 



The western Newer Basalt lava field. 



Development of a residual from, an extensive lava field. 

 Junction of confined and extensive lava field. Cros^s lateral. 

 Significance of the cross lateral. 



IV. — Distrihution of residuals and classification of valleys. 



Confines of two systems. 

 Eesiduals of Western Port system. 

 Eesiduals of Port Phillip system. 

 Svstematic classification of vallevs. 



Sf/nops\'S of Paper. 



Acknowledgments. 



Bihliography. 



The Lava Residual and^ its Physiographical Significajice. 



Lava residuals (Fig. 1). or those particular topographical forms 

 known by such more or less inappropriate terms as " high level 



Hypothpi^ 



^^{o/ 



Surfa ce^ of mf i Hi n^_L3v 



-IncTdenceoi Latere 



"ejuvenated) 

 Sea- level- 



Fig. 1. 



Section of a residual developed from a. confined older Basalt lava field at 



Upper Pakeaham. 



