National Park of American Samoa National Park Service American Samoa U.S. Department of the Interior Geologic Map of National Park of American Samoa Pt 25 25 20 2o5 $ o 20 o o o S# 20 $PL$UG 25 25 o $ Pt o$ o 5 $ Ra o 3 $ Pm o Ra $$ $ $ 2 o 10 Pt $ o $ $ Ra Pol P a c i f i c O c e a n 20$ 10 $ o o10 Ra Ra Ra o Pa 15 Ra $ $ Ra Ppe $ o o 25 Ra $ Pt $ $o $ 15 Ra o $ $ 18 o $ Ppt Ra 15 o3o5 10o 20 10 $ o $ 18 5o18 35 $ $ o 25 o Tutuila o o $ Ra o Ppt $ $ Ppi 15 10 $22o $ o $ 32 o $ Ra Rat 15 8 20 o Ra S# o 25 o$ $ 25 Ra 10 $ 2$0$ S#o$ o o 15 o Ra $$$6 $$ o $ Ra S# o 10 o o Pt o $ 35 $ $ Ppi 55 28 $ 6 $ o $ $ o Ppe $$ Ppt Ppi $ 5 Ra S# 10 Ra o 8 o $$$ $ o Ra Ra Po Ppeo Ra 15 16 $ 15 Qb o Qa 7o o14 o7 $ o oo Qa Rlc Qft 24 Qlel o o o 7 15 20 10 20 34 Tle Qfl $ o o $ $ o 25 Qlp Ra $$ 14 o 10 Ra o o $ 19 Rlc Landfill e e $ Qb Qtc 11 o $ Ofu o $ $ 14 17 Ra Ra Rll e Qte 1o1 Po 12 Qa o o Olosega 10 13 o Qa o o28 18 o e e 5 o 6 o e Qb 15 10 Qle Qnt Ttai Qa o 5 o 15 o Rla 22 13 24 Qb 6 Tle o o o o o Tafb o 15 Rll Qb o Qeli o Qb o e15 18 o 17 Ttae Tts e1o 0 10 Qa Qa Qlil e o Rlt 20 Qnl 6 11 o Qa Qa o o 6 15 o Qa 3 o 23 Qb Qa 10 o 2 o 35 o Tat 16 o 9 o Qb o Qb 10o 24 o 14 T'au o 7 o 19 10 o o P a c i f i c O c e a n 11o Qb e P a c i f i c O c e a n P a c i f i c O c e a n National Park of American Samoa Boundary Linear Dikes Geologic Units This map graphically presents digital geologic data prepared as part of the NPS Geologic Resources Qlp - Luatele Formation, pahoehoe flows Ppi - Pago Volcanic Series, lithic-vitric tuff Qnt - Nu’u Formation—tuff landfill Division’s Geologic Resource Evaluation Program. The source map used in creation of the digital geologic Qlc - Luatele Fm, poned lavas Ppi - Pago Volcanic Series, intra-caldera data product was: Geologic Attitude and Observation Localities o Ttae - Tuafanua Formation—A’ofa shield plug Qtec - Tunoa Fm, cinder cones - basalt & olivine basalt Pa - Alofau Volcanics strike and dip of beds Tuafanua Formation—Sili shield Ra - beach sand and alluvium Geology of Tutuila island - Harold T. Stearns, 1994, Geology of the Samoan Islands: Geological Society of Qte - Tunoa Fm, lava flows - basalt & olivine basalt Pol - Olomoana Volcanics America, Vol. 55, pp. 1279-1332. Scale approximately 1:63,000. ehorizontal beds Po - Taputapu Volcanics Rll - Leone Volcanics, pahoehoe flow Qtcc - Tunoa Fm, cinder cones - ash, tuff & olivine basalt Pm - Masefau Dike Complex Volcanic Point Features Geology of Tau island - Gary D. Stice and Floyd W. McCoy, Jr. 1968, Geology of the Manu’a Islands, Ppe - Pago Volcanic Series Rlc - Leone Volcanics, cinder cone S# Qtc - Tunoa Fm, ash, tuff & olivine basalt Ttae - Tuafanua Fm, A'ofa shield Samoa: Pacific Science, Vol. XXII. Scale approximately 1:56,000. plug Ppi - Pago V. Series—andesite/basalt flows Rla - Leone Volcanics, ash cone $ Qlel - Lata Fm, post-caldera lava flows Tts - Tuafanua Fm, Sili shield outcrop of vitric tuff or cinders Geology of Ofu and Olosega islands - Gary D. Stice and Floyd W. McCoy, Jr. 1968, Geology of the Manu’a Tle - Lata Formation—pre-caldera Rlt - Leone Volcanics, lithic-vitric tuff Qlec - Lata Fm, post-caldera cinder cone Ttai - Tuafanua Fm, ponded flows Islands, Samoa: Pacific Science, Vol. XXII. Scale approximately 1:56,000. Linear Volcanic Features Pa - Alofau Volcanics Rat - 'Aunu'u Tuff caldera, approximate Qle - Lata Fm, post caldera volcanics Tafi - Asaga Fm, associated plug Digital geologic data and cross sections for National Park of American Samoa, and all other digital geologic Pol - Olomoana Volcanics Qb - beach deposits data prepared as part of the Geologic Resource Evaluation Program, are available online at the NPS Data caldera, concealed Qlil - Lata Fm, intra-caldera associated lava flows Tafb - Asaga Fm, breccia cone Faults Pm - Masefau Dike Complex Qa - alluvium, talus and stream deposits Store: http://science.nature.nps.gov/nrdata/ Qlic - Lata Fm, intra-caldera cinder cone Tat - Asaga Fm, composite cone Geologic Contacts known or certain Qm - marsh Qli - Lata Fm, intra-caldera member Tam - tuff cone known or certain approximate Qnt - Nu'u Formation, lapilli tuff Pt - Trachyte plugs and dikes Tas - tuff cone approximate Qnl - Nu'u Formation, basalt flows concealed Ptp - Trachytic pumice deposits Tac - cinder cone shoreline Qfc - Fiti'uta Formation, cinder cone 0 1.25 2.5 5 Po - Taputapu Volcanics Tle - Lata Fm, pre-Caldera member Qfl - Fiti'uta Formation Kilometers Ppe - Pago Volcanic Series 0 1 2 4 Qft - Faleasao Formation Miles q Produced by Geologic Resources Division January 2008.