Click on the index link or scroll down to read the reports. A strong explosive eruption from North Pagan. While reporting strong felt seismicity on the island, radio operator Pedro Castro suddenly announced at that the volcano was erupting. Communication was then cut off. An infrared image from the GMS at showed a very bright circular cloud about 80 km in diameter over the volcano.
Weakening of activity was evident on the image returned at , and on the next image, at , feeding of the eruption cloud had stopped, with the proximal end of the cloud located about km SE of the volcano. Aircraft attempting to land on Pagan Island were prevented from doing so by the eruption. At , pilots reported a mushroom cloud over the island and ashfall over its N and E ends.
Ashfalls were also reported from Agrigan Island, km NW. Additional pilot reports at indicated that the eruption was intensifying and that the cloud had reached more than 7 km altitude. UPI reported that aircraft crews flying past the island at two different but unspecified times saw ash rising to Only one minor injury was reported.
When they overflew the island on 17 May at about , the eruption had ended. Lava had advanced about 1 km down the NE and NW flanks from the summit. The SW flank flow had partially covered the airstrip, but had stopped before reaching the village. Information Contacts: F. The material in quotes is excerpted from their report.
Material not between quote marks was abstracted from their tabular data. One resident visited the summit area 13 May and noted new ground cracks, sublimates, and increased gas emissions. At , residents heard a loud boom, followed immediately by the beginning of the eruption, first on the N flank then proceeding toward the S part of the summit area.
Geologic observations show that ash eruption and lava emission took place simultaneously during most of the eruption. Weather satellite images showed that the high-altitude ash cloud traveled SSE , but ash and scoria deposits on Pagan Island were thickest in the NW sector because of the prevailing SE winds at low altitude. At there was a notable decrease in plume height and density. Activity remained weak the next day except for a brief period of vigorous ash ejection reported by the USN around noon.
During an overflight between and on 18 May, only weak to moderate emission of blue fume was noted. The central vent was in a notch about m deep in the N rim of the old summit crater.
This vent probably ejected most of the material in the large eruption cloud, and it fed flows that went N, NNE, and W. The third and southernmost vent was in a notch about 80 m deep in the S rim of the old summit.
This vent fed flows that moved S. An increase in harmonic tremor level and the number of discrete higher frequency events began hours before the extrusion of minor aa lava flows from the S summit vent late early 22 May, and late 23 May.
A similar increase in seismicity during the midmorning of 24 May was followed by ash emission from both the N and S summit vents that lasted from early afternoon through the evening. As ash emission was decreasing during the evening of 24 May, extrusion of a small amount of aa lava occurred; lava extrusion also occurred during the evening and predawn hours of 25 and 26 May. Lava flows were predominantly aa and ranged from 3 to 30 m in thickness.
Fortunately, extremely devastating phenomena such as widespread pyroclastic flows did not take place. Lithic blocks and juvenile bombs as large as 1 m in diameter were thrown more than 2 km from the summit onto the N flank, and base surge phenomena, evidenced by low-amplitude cm dune and antidune features and preferential upslope tree damage, took place in restricted corridors down to elevations of m on the N and S slopes.
However, the present breaches on the N and S rims of the crater could channel potentially destructive pyroclastic flows into narrow corridors N and S of the summit. Such channeling may have occurred on 15 May and could occur again, even during the current eruptive cycle. An unknown volume of ash and scoria was deposited at sea and composed the ash plume that extended S of Guam. The longest lava flow 2. The N summit vent fed flows 1 km long, 0. The NE lobe of these northern flows traveled 1.
The N lobe traveled 3. The several lava flow and ash-ejecting events after 15 May were all of minor volume. Preliminary analyses of the gas samples by Paul Greenland HVO suggest that they contain a large portion of air mostly introduced into the vent system through the porous volcanic edifice.
When compared with gases of Kilauea Hawaii and Mt. The scoria sample was more or less typical of basalt of northern Marianas volcanoes table 1. Table 1. Chemical analyses of Pagan samples. Continued drainage of the lake or increases in temperature of the lake water would cause concern, because such changes could indicate that ground water might be heating in response to the proximity of hot rock in the volcanic edifice.
The overall trend of the tilt changes observed can be interpreted in terms of a possible inflation center NE of the lake near the N flank vent. In addition, fluctuations took place that could either be measurement noise or, if real, be associated with the largest eruptive events during our residence on the island 24 May ash event and 25 May lava event.
In general, changes above "noise" level were not seen in the lines measured from the instrument INS, figure 1 to the three nearest stations, but station TOP at elevation m moved steadily southward, 66 mm in 6 days. This movement could have resulted from inflation of the summit due to intrusion of a shallow magma body, gravitational instability of the summit area, or right-lateral movement on the N-S fissure system that formed during the eruption.
The ongoing harmonic tremor suggests that more secondary eruptive activity may take place. However, the deformation survey indicated possible swelling of the volcano, which may lead to an increase in future microearthquake activity and eventually to an eruptive event more significant than those of May. Larson, E. Further References. Banks, N. Sawada, Y. Information Contacts: N. Banks , R. Koyanagi , and K. Honma , HVO. Residents of Alamagan Island, [roughly 60 km] SSE of Pagan, observed mild ash ejection and "fire and smoke" emerging from the volcano around 11 June.
No additional activity has been reported. Banks , HVO. Fume emission rates from the new vent appeared to be significantly greater than the combined rate observed in late May from the three vents formed 15 May. However, no new lava flows were identified and ash accumulation downwind of the new vent was not appreciable. The new vent may have formed during the explosive activity observed from a nearby island 11 June.
Residents of Pagan Island. Explosive activity was occurring when they arrived about and continued through the day, accompanied by booming sounds. Scoria fell on the visitors, who also noted a strong odor of sulfur.
At about , a series of booming sounds was followed by ejection of a tephra column that rose about 1. Since a previous visit in September, 1 cm of ash had accumulated on the island's only village, 4 km from the summit. Residents of Agrigan Island, about 50 km NNW of Pagan, observed voluminous black columns rising from the volcano on 4, 5, and 6 January, and white plumes on other days in the first half of January.
The activity was preceded by three deep earthquakes near Pagan, on 3 January at , , and NEIS located preliminary hypocenters at No additional activity was reported until 8 February, when the mayor of the northern islands visited Pagan and found it erupting.
A minimum of five minor eruptions per day were observed through 23 February. At one point during this period date and time not yet determined , a "large smoke cover" from Pagan was observed over Saipan. Images of the area, returned by the NOAA 7 polar orbiting satellite times per day, were inspected 25 January February, but no eruption plumes were evident. The sample will be analyzed at HVO. The 53 residents of Pagan, evacuated during the second day of the eruption, have not yet been able to return for more than brief visits to the island.
Banks , HVO; Cmdr. Whitney , Office of the Rep. Personnel on a USN training flight observed activity at Pagan when they flew near the volcano about on 10 December.
A hole roughly 60 m below the crater rim on the NW side was spewing debris and brown smoke. Light-colored vapor was emerging from the center of the crater. Burning was seen along the S and SW slopes, but a cause could not be determined [see ].
Information Contacts: Cmdr. Walker and Lt. During the remainder of the visit, activity was limited to degassing. The gases were essentially atmospheric in composition, much different than the May gases, which had a high magmatic component.
Seismic monitors showed varying amounts of B-type events and harmonic tremor. More numerous and stronger seismic events preceded the ash eruptions of 7 and 15 March. Both EDM arrays showed minor deflation March.
Reoccupation of the original EDM line showed that 25 cm of net inflation had occurred on the higher slopes of the volcano between May and March , but the lack of other measurements between those dates prevented determination of shorter-term deformation trends. They also performed a water resource evaluation and sampled volcanic gases. The volume of the post-May tephra deposits is minor in comparison to that of the May deposit. It is difficult to assign eruption dates to each tephra layer because of the sporadic nature of observations on the island.
However, it is probable that a single lava flow and one of the tephra layers was produced on 11 June, Other eruptions were observed in November and January through February The date of emplacement of the uppermost and thickest tephra layers is uncertain. However, comparison of December aerial photographs with those taken in August suggested that these layers were emplaced during that interval.
In addition, during late September-October , residents of Saipan roughly km to the S reported a dark cloud, similar to the one ejected in May , drifting to the S. A preliminary microprobe analysis indicated that February eruption material was less differentiated than that of May but similar in composition to the magma The burning seen along the S and SW slopes was on another edifice on the opposite S end of the island, and was due to a brush fire, unrelated to eruptive activity.
The volume of individual tephra layers does not by itself suggest that Pagan was the source of the aerosols. However, they contain a large fraction of lithic material, suggestive of powerful gas jetting and erosion of the vent; lidar studies indicated that the source was at the approximate latitude of Pagan; and Pagan is the only volcano thought to have been in eruption at that latitude and at that time.
Thus, at present, Pagan remains the best possible source for the 'Mystery Cloud' of early On 1 September, personnel aboard a Continental Air Micronesia aircraft flying from Saipan to Japan reported "ash and smoke" at an altitude of 6 km within 15 km of the volcano. Scheduled flights pass directly over Pagan Island times per day, but no subsequent flights reported increased activity.
No eruption clouds were observed on satellite imagery. Technicians visited Pagan in late July, and saw only minor activity. Inspection of a checkpoint near the volcano on 29 July revealed no indication of major new ashfall since geologists left the island in mid-March. Pagan Island remains uninhabited, as it has since the major eruption of May , although residents and officials occasionally visit the island.
Pagan's mayor, on the island through late August, observed no change from the low-level late July activity. Information Contacts: R. Koyanagi , HVO; F. On 8 and 9 September USN personnel observed the volcano during pilot-navigation training flights. They described and photographed a plume containing a little ash that issued gently from the crater. Although heavy rain, lightning and convective weather cloud activity to more than 9 km obscured the view on the 8th, the plume was seen rising to 3.
A stratus layer extended km ENE at In clear conditions on the 9th, the rising plume and the stratus layer were again observed. Information Contacts: Lt. The only activity they observed was an explosive eruption accompanied by glow that began at on the 26th. That evening, glow remained visible.
Ash that fell on the village was collected from concrete slabs. The ash has been identified as magmatic, of medium-sand size, and depleted in fines. Since Pagan's major eruption in May , six or seven explosions have ejected enough tephra to cause ashfall in the village. The 26 September ash was the first to fall on the concrete slabs since they were swept clean in July. Visible images from NOAA 7 and NOAA 8 polar-orbiting satellites showed Pagan emitting a small, moisture-laden plume on about half of the days between 29 March and 8 May [on 29 and 31 March; 1,2,3,4,5,6,8,11,12,14,20,21,23,24,25, and 28 April weather clouds on April ; and 1 and 7 May].
When present, the plume extended km downwind, with its base at about 0. Occasionally the plume appeared as a haze, when its moisture had been lost downwind. Whether the moisture in the plume was vented by the volcano or acquired from the atmosphere has not been determined.
On 15 May, Pagan erupted twice. At residents of Agrigan Island, 65 km N, felt an earthquake, rushed from their homes, and saw a dark column rising km above Pagan. The eruption cloud, about 50 km in diameter, drifted NW. An Air Force weather reconnaissance plane, diverted to inspect the activity, observed no lava emission.
A second moderate eruption occured during the afternoon. Information Contacts: M. The crew of a Continental Air Micronesia flight that passed about 25 km W of Pagan at about 6 km altitude on 11 April at observed a large brown ash cloud obscuring the volcano.
The eruption column rose to about 2. On 15 April at , another Continental Air Micronesia flight passed over Pagan and the crew reported a new lava flow. Information on its size and position were not available.
On 1 May at about , Space Shuttle astronauts took nine photographs that showed a plume originating from near the center of the volcano and extending at least [] km to the SSW figure 2. The plume was dense near the volcano and appeared to contain some ash, but diffused rapidly as distance from Pagan increased.
He was honorably discharged after five years. The U. During summers in high school, he took a boat up to Pagan with his father where they fished and lived off the land. Like other former Pagan residents and their relatives, Kaipat and his father visit the island for months at a time, depending on the availability of transportation and supplies. The longest that Kaipat lived there continuously was for a year and a half after he got out of the Marine Corps.
Despite its isolation, Kaipat loved it. He would hunt coconut crabs and catch reef fish. He felt closer to his Carolinian and Palauan heritage. When he decided to go to college, he had to move back to Saipan to enroll. The year-old still wants to return to Pagan eventually. But that might not be possible now that the Navy wants to use the northern part of Pagan for bombing practice and other war games.
If the plan gets approved, the beaches where Kaipat and others used to fish and swim will be dredged, and access to the island could be limited during the four months of annual training. That worries former residents like Kaipat who fear any war games will destroy Pagan and make it impossible for anyone to move back. The commonwealth government still recognizes Pagan and neighboring undeveloped islands as a separate political district, and their mayor, Jerome Aldan, is adamantly opposed to the plans.
His administration is even moving forward with a long-awaited homesteading program on Pagan. Even the federal Environmental Protection Agency is criticizing the Navy for the potential destruction of rare coral species that are already under stress from climate change.
The Department of Defense is already bombing the nearby island of Farallon de Medinilla, and has been doing so since The same qualities that make the island good for military training also make it a desirable place to live. His family lived in a two-room house where he and his siblings would sleep in one bedroom with their parents. They also raised pigs, chickens and goats. Copra is dried coconut meat that can be used to make oil.
Back then, in the s, ships would come from Japan to buy copra every month, Diego remembers. Pagan, like the rest of the Mariana Islands, was traditionally home to indigenous Chamorro people. Historic artifacts found on the island date back hundreds of years.
After Magellan landed on Guam, the entire island chain came under Spanish rule. During the 17th century, Spanish colonizers forcefully relocated Pagan residents in an effort to concentrate Chamorros and indoctrinate them in Catholicism.
Soon hundreds of residents moved back to Pagan illegally and the Spanish government forcefully removed them again. They built a runway, troop barracks and bunkers to store bombs and fuel. Americans bombed Pagan, and after winning over the Northern Marianas, the U. After the war some indigenous people still wanted to go back, and dozens finally did in He remembers how ships would come regularly and villagers would buy rice, soy sauce, coffee and other supplies.
Sometimes tourists would visit on cruise ships and enjoy the hot springs. Image of the Day Land. EO Explorer. Pagan Island, Northern Marianas. At the time of publication, it represented the best available science.
View this area in EO Explorer. View more Images of the Day:. Immediately off the northern east coast are the very small and steeo rock islets Togari Rock , high and Hira Rock , which are listed as separate islands among those islands constituting the Northern Islands Municipality. As of the population of Pagan often changed as secondary students moved back and forth between their residences on Pagan and their schools on Saipan. In October Pagan had seven families with a total of 37 people.
The resident commissioner's office stated that 51 people lived on Pagan in December As of Pagan had nine families with total of 85 people, including some people residing in Saipan. The proposal spawned an online community called Our Islands are Sacred, a petition on Change. According to Michael G. According to an article by James Cave for the Huffington Post, an article which used Hadfield as its source:.
According to an April 17, , article by Wyatt Olson for Stars and Stripes military news network, "the of the Northern Mariana Islands is considering a joint resolution calling on the governor to oppose the military expansion on the mile-long island. Map Hotels Places. History Archaeological finds indicate that Pagan was settled from several centuries BC. Politically, Pagan remains part of the Northern Islands Municipality.
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