114:
Normal faults are common on the island, particularly the
Angingan fault which places Fina-sisu Formation volcanic rocks against younger limestones. Geologists have identified breccia near Mount Tapkpochao as the trace of a normal fault. The Angingan, Obyan and Dago faults may be part of a larger,
81:
The
Matansa Limestone grades laterally to a pure shallow-marine limestone and like other units shows conflicting results when biostratigraphy and isotope dating are compared. The Tagpochau Limestone is the second most extensive rock unit near the surface on Saipan after the Mariana Limestone. It
85:
Calcareous marine tuff and interbedded volcanic flow rocks near the village of As Lito and the Fina Sisu hills was named the Fina-sisu
Formation in 1956. The tuff is well bedded with numerous plankton fossils. Geologists have inferred that the rock formed during the
78:. The Densinyama Formation includes andesitic breccia, conglomerate, tuff sandstone and tuff limestone, centered around Mount Talafofo and discontinuously exposed by Achuguo Spring in the west. It overlies the Hagman Formation and is present close to Papago.
65:
Originally called the Hagman andesite by R. Tayama during initial research efforts in 1938, the Hagman
Formation is exposed as cliffs along the Hagman Peninsula and deposited during the early development of the Mariana fore arc. The andesite lava flows,
115:
anastomosing fault system, running on both sides of the central highlands and connecting with faults in the area of
Suicide Cliffs and Fanonchuluyan Bay. Most faults trend north-south and even young rocks from the Holocene show signs of offset.
773:
46:
volcanic rocks, belonging to the Izu-Bonin-Mariana (IBM) arc system. Saipan is on the frontal arc of the system and experienced periodic uplift and subsidence since then. Volcaniclastic and carbonate rocks overly the IBM volcanics.
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The Donni
Sandstone Member of the Tagpochau Limestone is informally known as the Donni formation. It is exposed near the village of I Donni and throughout the eastern end of the island. The formation overtops the
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Tagpochau rocks with an angular unconformity. Talus, marsh sediments and limestones such as the
Mariana Limestone are common across the surface, resulting from deposition and mass-wasting during the
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found mainly on north-central part of the island. Radiometric dating gives an age of 45 million years ago. During mapping in 1956, it was subdivided into flow rock,
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27:. Islands such as Saipan show a variety of rock types including volcanic rocks, breccia, tuff, conglomerate, sandstone, clay and extensive limestones.
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The bulk of geological research in the
Northern Mariana Islands has focused on the large, populous island of
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39:. The U.S. Geological Survey first mapped the island in 1956 and it was remapped again in 2007.
134:"Preliminary geologic map of the island of Saipan, Commonwealth of the Northern Mariana Islands"
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The
Sankakuyama Formation is the oldest individual rock unit, which includes Eocene
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of the unit date to between 26 and 28 million years ago, during the
59:
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Landing
Beaches; Aslito/Isely Field; & Marpi Point
23:
began to form with undersea volcanic eruptions in the
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824:Japanese Jail Historic and Archeological District
31:Geologic History, Stratigraphy & Tectonics
1111:
894:Chudang Palii Japanese WWII Defensive Complex
159:
90:and is overlain by the Tagpochau Limestone.
8:
132:Weary, David J.; Burton, William C. (2011).
82:include a limestone, marl and tuff facies.
42:The oldest rocks exposed at the surface are
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1483:Geography of the Northern Mariana Islands
929:Nanyo Kohatsu Kabushiki Kaisha Sugar Mill
362:Marianas Trench Marine National Monument
124:
960:Nanyo Kohatsu Kabushiki Kaisha complex
7:
865:Unai Lagua Japanese Defense Pillbox
990:Our Lady of Mount Carmel Cathedral
14:
1050:NMI Museum of History and Culture
860:Unai Achugao Archaeological Site
814:Japanese 20mm Cannon Blockhouse
1:
970:Unai Dangkulo Petroglyph Site
1478:Geology of the United States
1127:Geology of the United States
914:Japanese Coastal Defense Gun
757:Tinian International Airport
747:Saipan International Airport
673:Dr. Rita Hocog Inos Jr-Sr HS
1499:
752:Rota International Airport
722:Northern Marianas College
185:
1429:Northern Mariana Islands
839:Laulau Kattan Latte Site
706:Grace Christian Academy
696:Marianas Baptist Academy
179:Northern Mariana Islands
62:and pyroclastic rocks.
20:Northern Mariana Islands
1065:Garapan Heritage Trail
939:Rota Latte Stone Quarry
909:Dugi Archeological Site
899:Chugai' Pictograph Site
1129:by political division
904:Commissioner's Office
870:Unai Obyan Latte Site
794:Campaneyan Kristo Rai
288:Farallon de Medinilla
995:Saipan Katori Shrine
691:Saipan International
1439:U.S. Virgin Islands
1060:Sugar Dock (Saipan)
1043:Museums and History
1034:Television stations
829:Japanese Lighthouse
293:Farallon de Pajaros
851:(Laderan Banadero)
679:Saipan Southern HS
110:Structural geology
1465:
1464:
1093:
1092:
1085:Tinian Naval Base
1080:Naval Base Saipan
1003:
1002:
978:
977:
919:Japanese Hospital
819:Japanese Hospital
735:
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637:
636:
609:Carolinas Heights
370:
369:
227:Per capita income
1490:
1449:Outlying islands
1403:Washington, D.C.
1397:Federal district
1120:
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1106:
1097:
1075:Battle of Tinian
1070:Battle of Saipan
1016:Marianas Variety
779:
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619:Marpo Heights II
537:Oleai (San Jose)
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384:Northern Islands
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18:geology of the
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1377:West Virginia
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849:Suicide Cliff
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614:Marpo Heights
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472:Chalan Laulau
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1434:Puerto Rico
1428:
1342:South Dakota
1332:Rhode Island
1327:Pennsylvania
1307:North Dakota
1021:
1014:
876:
789:Banzai Cliff
701:Mount Carmel
624:Marpo Valley
512:Kannat Tabla
462:Chalan Kanoa
457:Capitol Hill
309:Maug Islands
187:
175:Commonwealth
127:
113:
92:
84:
80:
68:conglomerate
64:
49:
41:
34:
17:
15:
1411:Territories
1257:Mississippi
1172:Connecticut
965:North Field
809:Isley Field
684:Tinian M-HS
667:Marianas HS
562:San Vicente
552:San Antonio
517:Koblerville
477:Chalan Piao
467:Chalan Kiya
408:Settlements
207:Archipelago
100:Pleistocene
1472:Categories
1372:Washington
1292:New Mexico
1287:New Jersey
1162:California
547:Sadog Tasi
522:Lower Base
482:China Town
452:As Terlaje
442:As Perdido
119:References
1382:Wisconsin
1347:Tennessee
1252:Minnesota
1227:Louisiana
855:Tachognya
766:Landmarks
661:Kagman HS
642:Education
557:San Roque
532:Navy Hill
502:Gualo Rai
492:Fina Sisu
437:As Matuis
295:(Urracas)
269:(Aguijan)
263:(Agrigan)
244:Geography
212:Geography
192:(capital)
88:Oligocene
76:Oligocene
72:sandstone
1367:Virginia
1317:Oklahoma
1297:New York
1272:Nebraska
1262:Missouri
1247:Michigan
1237:Maryland
1222:Kentucky
1202:Illinois
1177:Delaware
1167:Colorado
1157:Arkansas
875:Waherak
844:Mañagaha
669:(Saipan)
663:(Saipan)
629:San Jose
593:Songsong
588:Sinapalo
304:Mañagaha
283:Asuncion
278:Anatahan
273:Alamagan
267:Aguiguan
234:Campaign
217:Politics
104:Holocene
52:rhyolite
1387:Wyoming
1362:Vermont
1267:Montana
1207:Indiana
1187:Georgia
1182:Florida
1152:Arizona
1142:Alabama
934:Rectory
924:Mochong
656:CNMIPSS
572:Tanapag
497:Garapan
432:As Lito
427:Achugao
422:Afetnas
331:Sarigan
311:(Ma'ok)
261:Agrihan
253:Islands
222:Economy
177:of the
96:Miocene
56:breccia
1322:Oregon
1277:Nevada
1217:Kansas
1192:Hawaii
1147:Alaska
1135:States
948:Tinian
877:Maihar
782:Saipan
675:(Rota)
602:Tinian
567:Susupe
542:Papago
507:Kagman
487:Dandan
447:As Teo
415:Saipan
399:Tinian
394:Saipan
336:Tinian
326:Saipan
322:(Luta)
299:Guguan
199:Topics
189:Saipan
44:Eocene
37:Saipan
25:Eocene
1352:Texas
1232:Maine
1197:Idaho
1008:Media
715:Other
527:Marpi
350:Other
315:Pagan
1424:Guam
1357:Utah
1312:Ohio
1212:Iowa
887:Rota
649:K-12
581:Rota
389:Rota
320:Rota
102:and
70:and
60:tuff
16:The
106:.
1474::
58:,
1119:e
1112:t
1105:v
167:e
160:t
153:v
136:.
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