These data show parallel structures aligned in a southwest-northeast directions to the southwest of the island. No shallow data were collected around Aguijan due to time limitations.
Tinian and the nearby Aguijan Island form the Tinian Municipality. Tatsumi Reef, a popular fishing area, lies three km southeast of Tinian. The major population center is San Jose. Tinian has a land area of sq. In the U. The island was captured by U. These runways were used to launch U. Two-thirds of Tinian — over 16, acres, is currently leased to the U.
In a casino was constructed on Tinian, and a major source of revenue on the island comes from tourists who come from Saipan on day trips via boat or air. Multibeam data were collected around Tinian in both and and optical validation data were collected in and Almost complete multibeam coverage was achieved between 20 and m with significant amounts of data down to m.
The island is approximately 20 km long and 9 km wide with an area of sq. Of the eight communities on Saipan, Garapan and Chalan Kanoa are the principal population centers.
Saipan has been continuously populated since the Chamorro arrived about four centuries ago and was under Spanish and then German rule until It became a protectorate of Japan and was a major sugarcane growing and processing center until WWII.
In summer , the U. Fierce land battles were fought in Saipan with heavy losses on both sides. There is a large offshore anchorage where commercial and military ships are anchored, providing another source of income; the U. Multibeam data were collected around Saipan in both and , and limited optical data were collected in and Almost continuous multibeam coverage is available from depths of 20 m to over m with some data as deep as m. Features related to mass wasting and erosion, such as debris blocks and canyons and channels, characterize the seafloor around Saipan.
A number of shallow terraces related to previous stands of the sea were mapped in the frontal arc. On the western side of Saipan at the Garapan Anchorage, there are two large, offshore banks with an area of over 50sq. It is approximately 9 km long by 4 km wide and is oriented in a northeast to southwest alignment similar to Tatsumi Reef, which lies south of Tinian.
Marpi Bank is also a popular fishing location. Anatahan is a small volcanic island km north of Saipan. It is 9 km long and 3 km wide with an area of It is located at latitude Small sporadic human settlements have occurred on many of the northern islands.
In the early German period , administrator Georg Fritz found evidence of huts from Carolinian workers who had harvested copra, but no archaeological evidence of Chamorro habitation. During the Japanese period Anatahan had a small population of Carolinian islanders and Japanese working on a copra plantation.
In , 32 survivors from a Japanese shipwreck arrived on Anatahan, where one female and one male Japanese settler still remained. These Japanese did not believe that WWII had ended until when the few remaining survivors were removed from the island. Resulting damage to the native forest and erosion were observed to have escalated in the s, possibly exacerbated by an El Nino-related drought in the late s.
This damage is of particular importance because of its impact on the threatened Mariana fruit bat population. Photographic evidence spanning from to documented widespread loss of forest, but remnants of a mixed broadleaf forest Aglaia-Elaeocarpus do still exist on Anatahan. An ungulate eradication program was started in , but this was interrupted by the volcanic eruptions. In all Northern Mariana residents from Anatahan, Alamagan, and Agrihan were evacuated to Saipan when the Anatahan eruption threatened.
The first historical eruption of Anatahan Volcano began violently and suddenly on the evening of May 10, and continued until June ; low level seismic activity and tremors have continued, but decreased since that time. Access to the island has been severely limited due to this eruptive activity.
Underwater surveys in September showed that coral communities had been largely covered with volcanic ash. Only a limited amount of multibeam data was collected in during the recovery of a single moored oceanographic instrument. However, several previous academic and government cruises have collected multibeam data around Anatahan.
Ikonos imagery Space Imaging Inc. It is approximately 2. Archaeological studies by Georg Fritz, the first administrator of the German colonial district of the Mariana Islands, found pottery and latte stones, a symbol of Chamorro culture and identity, on Sarigan Island. Under the German and Japanese administrations, Sarigan was cultivated as a copra plantation and residents lived there from to when they were evacuated.
Between and the German authorities leased eight islands including Sarigan to exploit the bird populations for the Japanese and European hat plumage trade. Tropic birds, brown boobies, frigate birds and white terns were the primary species of interest. At one point there were 14 Carolinian and Japanese bird catchers on Sarigan, but because of low bird counts all but two were removed.
Some native forest remains on Sarigan, but it was being decimated by feral pigs, goats and cats. Therefore between and the Dept. Remnants of a mixed broadleaf forest Aglaia-Elaeocarpus still exist on Sarigan. This island has been chosen as a potential site for relocating native bird species, which are in danger because of the brown tree snake on Guam and other southern islands. The micronesian megapode, a pigeon sized bird found on the forest floor, still exists on Sarigan with birds on Sarigan and between and birds in the entire Archipelago.
Stands of coconut trees are seen near the shore, and the crater is visible at the top of the island. On Sarigan, a low truncated cone with a m-wide summit crater contains a small ashcone. The youngest eruptions produced two lava domes from vents above and near the south crater rim.
Lava flo from each dome reached the coast and extended out to sea, forming irregular shorelines. The northern flow overtopped the crater rim on the north and northwest sides. The sparse vegetation on the flows indicates they are of Holocene age. There are no known historic eruptions on Sarigan, but a seismic swarm with more than 63 earthquakes was recorded in August A bathymetric rise to the east of Sarigan, only partially mapped, rises from to m below sea level.
In , multibeam data were collected around Sarigan in and m depths. A small shelf extends 2 km east of the island with two platforms — one at m and a deeper one at m. Evidence of mass wasting and erosion surround the island with a small secondary feature, possibly another cone, on the southern flank of the volcano.
About 33 km to the east of Sarigan an intriguing feature, only partially mapped, rises from to m. It is 3 km long and 2 km wide with an area of approximately 4 sq. German administrator Georg Fritz found no archaeological record of Chamorro occupation on the northern part of Guguan Island.
Between and the German authorities leased eight islands including Guguan to exploit the bird populations for the Japanese and European hat plumage trade.
Three Japanese bird catchers on Guguan were listed as having caught tropicbirds, boobies, and frigate birds in a five month period. Guguan is a Northern Mariana Conservation Area and was declared a wildlife preserve in by the Marina Constitution.
Guguan has an eroded volcano on the south, a caldera with a post-caldera cone and a northern volcano, which has a breached summit crater that fed lava flows to the west. The only known eruption took place between and and produced the northern volcano and lava flows that reached the coast.
Multibeam sonar data were collected around Guguan in in water depths between 20 and m on all sides and to almost meters on the eastern side. The multibeam bathymetry data show two shelves extending 2 km offshore around the southern portion of the island — one in depths of 25 to 50 m and the second in 80 to m depths.
The steep underwater flanks of the volcano show much less evidence of mass wasting and erosion than do other volcanoes in the chain. Fifteen km to the southeast sparse multibeam data hint at a structure that may be similar to the one seen to the east of Sarigan. It is 4. On Alamagan in Georg Fritz, the first German administrator, found several latte sets, a symbol of the Chomorro culture, made of basalt columns, a stone paved area and a stone-lined well or pit filled with pottery.
Alamagan has been sporadically populated since that time. The census recorded a population of 6 inhabitants on Alamagan. Cows, pigs, and goats are also common on the island. Alamagan is the only one of the northern islands that is home to an endemic endangered bird species, the Nightengale Reed Warbler; it also had an estimated population of 30 endangered Mariana megapode in Alamagan has recently been selected by the Western Pacific Fisheries Management Council as a site for a remote fishing station.
Alamagan has a m deep summit crater east of the center of the island. Multibeam sonar data were collected around Alamagan in in water depths between 20 and m on all sides and to greater than meters on the eastern side. The multibeam data show a narrow 3 km long shelf running out from the southeastern shore of the island with depths ranging from 25 to m.
Extensive evidence of mass wasting can be found on all sides of the island. It is 17 km long and 7 km at the widest with an area of approximately It is the 4th largest of the islands of CNMI.
On Pagan in Georg Fritz, the first German administrator, found several basalt latte sets — a symbol of the Chamorro culture — as well as sling stones and cultivated plants that are all signs of previous occupation. The commander of Pagan Island surrendered almost at the same time as the overall Japanese surrender in early September, In , 53 residents were evacuated after a major volcanic eruption on Pagan. Residents have been petitioning to return, but there has been reluctance on the part of the government due to continued volcanic threat.
Goats are also common on the island, but because much of the arable land was covered by the eruption most of the livestock was depleted by starvation at that time.
Pagan was also home to an estimated fruit bats in It is believed that the Pagan megapode may have become extinct on Pagan after the eruption. There is a shallow brackish lake on the northern part of the island and remnants of a mixed broadleaf forest Aglaia-Elaeocarpus still exist.
Pagan is one of the largest and most active of the Mariana volcanoes and is formed by two volcanoes connected by a narrow isthmus.
The northern volcano, Mount Pagan, has a summit height of m and a 7 km diameter crater. After the eruption, volcanic activity continued steadily through In December through January ashfall and ash plumes were observed from Mount Pagan. South Pagan has a summit height of m and a 4 km wide caldera. Multibeam sonar data were collected around Pagan in in water depths between 20 and m on all sides and to greater than meters on the eastern side.
The multibeam data show a 2. Three distinct levels are seen — at m depths, m depths, and at m depths. There is a narrow anchorage area on the western side of the isthmus in m water depths.
A small peninsula on eastern side of the island is a dike complex surrounded by a small shelf in m water depths. In all other areas there are steep slopes down to m or deeper with evidence of mass wasting and erosion, especially on the north and south flanks. It is 10 km long and 7 km wide with an area of approximately 47 sq.
It is the highest point in CNMI and the largest single volcano. Agrihan was the site of the last stand of the Chamorro against the Spanish after which all Chamorro were removed to Guam.
According to the Encyclopedia Britannica , colonists from the United States and Hawaii established plantations in , but were expelled by the Spanish.
During the German period of colonization, Agrihan was one of the islands that was leased for the purpose of collecting bird feathers for the European and Japanese hat trade between and Agrihan has fertile highlands with palm trees on the lower slopes and phosphate deposits.
Remnants of a mixed broadleaf forest Aglaia-Elaeocarpus exist on Agrihan. It has been sporadically populated. Residents were evacuated in , the only historic volcanic eruption. In all Northern Mariana residents from Anatahan, Alamagan, and Agrihan were evacuated to Saipan when the Anatahan eruption occurred. Agrihan has a small caldera 1 x 2 km that is breached to the NW, where a lava flow extends to the coast and forms a delta.
The only historic eruption was in when large blocks and 3 m of ash were deposited on a village on the SE coast. Multibeam sonar data were collected around Agrihan in in water depths down to m on all sides. The multibeam data show a 1-km wide shallow shelf on the southwest corner of the island in water depths down to 50 m.
Steep drop offs are seen on and there is extensive evidence of mass wasting and erosion on all flanks of the island. The picture shows the steep Asuncion sea cliffs. Landslide scars are visible in the left side of the photo. It is 3. Although currently uninhabited, extensive coconut groves might indicate that some copra production was once done there. In addition, Asuncion was leased by the German authorities from to for the purpose of harvesting bird feathers for the European and Japanese plumage trade.
Six bird catchers were supposed to be on Asuncion, but human corpses were seen on the beach in when visited by the German station chief. Asuncion has the most extensive native forest found on the northern islands, with a scrubby, mixed-broadleaf forest dominated by Terminalia spp. These deciduous, indigenous trees have edible kernels that may have been favored by early human inhabitants.
The seed of the tree is dispersed by fruit bats which feed on the husk. The above blank map represents The Northern Mariana Islands - an insular area and commonwealth of the United States consisting of 15 islands of the Mariana archipelago except Guam , situated in the northwestern Pacific Ocean. The above map can be downloaded, printed and used for geography education purposes like map-pointing and coloring activities. The above outline map represents The Northern Mariana Islands - an insular area and commonwealth of the United States consisting of 15 islands of the Mariana archipelago except Guam , situated in the northwestern Pacific Ocean.
This page was last updated on November 23, Home Northern Mariana Islands. Outline Map Key Facts Flag. Caminito del Rey. Angels Landing. Salt Spring Island. Old Faithful Geyser. Kuril Islands.
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