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member by normal faults bounding the caldera. 
Intra-caldera lavas include picrite-basalts (both 
ankaramites and oceanites), olivine basalts, 
hawaiites, and possibly one or two flows of 
mugearite. In addition, there are extensive de- 
posits of ash and lapilli tuff. The flows vary 
from 5 feet to more than 30 feet in thickness. 
Nearly horizontal ash beds cover much of the 
remaining caldera floor. 
The caldera was only partly filled. At least 
Fig. 4. Ta’u Island. Top: Looking north into the Lata caldera toward Lata Mountain (A), the curved 
cliff (£) between the benches at ’Ele’elesa and Afuatai, the bench at Tali’i (C). 
Middle : Looking east toward the cliff bounding the Tunoa depression (A), Olomatimu (B), and Lepu’e 
(C) craters in background, the old sea cliff behind Ta’u Village (D), which has been buried by the Faleasao 
tuff cone (£). 
Bottom : Looking northwest toward the nearly horizontal lava flows of the Fitiiuta formation, which have been 
built out in front of the old sea cliff cut into the Luatele shield. 
