8. Powers — Explosive Ejectamenta of Kilauea. 231 



and probably has its continuation in one of the red lava-flows 

 seen about 20 feet above the floor. 



Other ash sections must occur in the walls of Kilauea, but 

 they have not been carefully examined. 



Younger Ejectamenta. 



The younger deposits of explosive material are found every- 

 where in the vicinity of Kilauea: on the road to Hilo, 6 miles 

 to the east of Halemaumau ; at the Keauhou Pali, 8 miles 

 south ; near the Halfway House on the road to Kau, 8 miles 



Fig. 2. 



Fig. 2. The unconformity at the base of the cliffs at Uwekahuna (marked 

 by crosses). The unconformity is overlain by ash against which the thick 

 flows on the right side of the picture end. The ash bed can be traced on an 

 almost horizontal line for a mile to the right of this section. 



southwest ; in the Koa forest, 6 miles north. The ejectamenta 

 consist of ash, thread-lace scoria,* bombs, and fragments of rock 

 and ordinary scoria of various sizes. 



* Thread-lace scoria is a variety of basaltic pumice first described by 

 Dana, in which the vesicles comprise 98 to 99 per cent of the mass, their 

 walls being sieve-like or similar to thread-lace in texture. See this Journal 

 (3), xviii, p. 134, 1879 ; Characteristics of Volcanoes, New York, 1891. 



