212 S. Powers — Explosive Ejectamenta of Kilauea. 



The maximum thickness — over 10 feet — at the base of the 

 mountain appears to be on the northeast side from Pepeekeo 

 to Maulua Bay. 



The ash deposits near the Mohokea depression have already 

 been described by Hitchcock* and by Emerson. f Their source 

 is ascribed to Mokuaweovveo by the former, because of certain 

 other deposits of ash at Humnula, on the plateau between 

 Mauna Loa and Manna Kea (this ash may have come from the 

 latter mountain), and to Mohokea by the latter writer. The 

 latter view is here favored because the deposit is confined to 

 the Mohokea district, and is not reported on the upper slopes 

 of Mauna Loa. 



The Mohokea ash extends from the vicinity of the Kapapala 

 ranch, west of Kilauea, past the Mohokea shield-shaped depres- 

 sion and Kaalualu, to the southernmost point of the island, Ka 

 Lae, a total distance of 29 miles. The direction of the trade 

 winds is from Mohokea toward Ka Lae, which places are 21 

 miles apart. There is a surface deposit of ash, covered by 

 later flows from Puu Enuhe to Hilea on the south side of the 

 Mohokea depression, and from the cliff, which extends south- 

 eastward from Waiohinu, nearly to Kaalualu ; and there are 

 also older deposits interbedded with lava flows, as seen in ex- 

 posures in the Mohokea district, especially near Kaumaikeohu, 

 at Honuapo, and near Kaalualu. 



The thickest section observed occurs in a stream bed near 

 Kaumaikeohu. The gulch was followed downstream for about 

 half a mile only and it is probable that other flows and ash 

 beds are exposed below this point. The section is as follows : 



Top, 



an < 



erosion surface 



4 ± feet ash 



5-20 



C( 



pahoehoe 



K) + 



<< 



ash 



4 



c« 



pahoehoe 



15 ± 



a 



ash, containing blocks of vesicular 

 basalt 1 foot in diameter. 



6 



C( 



ash and ejectamenta 



6 



it 



ash 



10 



a 



pahoehoe 



10 



a 



ash (black) 



? 



a 



pahoehoe 



Base not seen. 



At Honuapo a section is exposed at the sea in a cliff which 

 has probably been formed by a landslide in 1868 (or 1887). 

 Northwest of the house at Kaalualu in a small dry gulch 



* Op. cit,, pp. 154-158. f Op. cit. 



