Kamaʻehuakanaloa Seamount

Lōʻihi Seamount is an active undersea volcano that lies approximately 48 km (30 mi) off the southeast coast of the island of Hawaiʻi, on the flank of Mauna Loa, the largest shield volcano on Earth. Lōʻihi is the newest volcano in the Hawaiian-Emperor seamount chain, a string of volcanoes that stretches over 5,800 km (3,604 mi) northwest of Lōʻihi and the island of Hawaiʻi. Unlike most Pacific volcanoes, which form on the Pacific Ring of Fire, Lōʻihi is a hotspot volcano that has formed thousands of miles from the nearest plate boundary, created by the Hawaii hotspot.

Volcanoes in the Hawaiian Islands arise from the Hawaiʻi hotspot, and Lōʻihi represents the youngest volcano in the deep submarine preshield stage. Lōʻihi is expected to emerge above sea level in about 10,000-100,000 years; it may become a new and separate Hawaiian island, but most likely it will merge and coalesce with the other volcanoes making up the island of Hawaiʻi. Lōʻihi is taller than Mount St. Helens in spite of being 975 m (3,199 ft) underwater, and is home to a diverse microbial community around its many hydrothermal vents.

In 1996, Lōʻihi was rocked by the first ever directly observed eruption of an active underwater volcano in Hawaiʻi. The eruption was preceded by a swarm of 4,070 earthquakes, the largest of any Hawaiian volcanic eruptions. A total of 4 to 5 square miles of the summit was altered; one section, Pele's Vents, collapsed entirely upon itself, and formed the renamed Pele's Pit. The volcano has remained relatively active and is monitored by the National Oceanic and Atmospheric Administration and the United States Geological Survey for changes. A submarine observatory (Hawaii Undersea Geological Observatory or HUGO) provided valuable real-time data of Lōʻihi from 1997 to 2002. Lōʻihi last erupted in 1996.

Characteristics

Geological

See also: Evolution of Hawaiian volcanoes

Lōʻihi is a seamount (underwater volcano) located on the flank of Mauna Loa, the largest shield volcano on Earth. It is the newest volcano in the massive Hawaiian-Emperor seamount chain, created by the Hawaiʻi hotspot. Lōʻihi's rift zone is about 19 mi (31 km) long and oriented northwest-southeast across the 2.8 by 3.7 kilometres (1.7 mi × 2.3 mi) top of the caldera. The distance between the summits is about 80 km (80,000 m), which is also the approximate diameter of the hotspot.

Bathymetric mapping of Lōʻihi. The arrow points to Pele's Pit.

The summit of Lōʻihi has a caldera depression and sports three craters. Pele's Pit is the largest of these three craters, and formed in July 1996 when a vent collapsed into a large depression with 200 m (660 ft) walls. In relative age, the western-most pit is the oldest, with the eastern pit being of a younger age and Pele's Pit being easily the youngest (having formed extremely recently in 1996). Thick walls (about 20 m (66 ft)), unusual to Hawaiian volcanic craters, seem to indicate that the craters had been filled and refilled multiple times in the past. Lōʻihi is also unusually thick for a Hawaiʻi volcano, with estimates for the thickest part of its base being around 3.5 km (2 mi). However, its early geological setting means that the volcano was first constructed on a thin debris field, so it might be considerable thicker at its bottom maxim, as much as 5 km (3 mi).

Lōʻihi is dissected by two prominent rift zones, contributing to the elongate shape of the volcano. This shape and position is cited as evidence that the rift zones formed early in Lōʻihi's history, for if they had formed later Lōʻihi would be more conical or star-shaped. Lōʻihi's northern rift zone is about 11 km (7 mi) long, and the longer, more southerly rift zone is about 19 km (12 mi) in length. Observations show that both parts lack a sediment cover, indicating recent activity. A bulge exists in the western part of the north swell, with three 60 m (197 ft) to 80 m (262 ft) cone-shaped prominences. This bulge may be a new rift zone, but it is most probably the result of isolated flank eruptions.

Up until the 1970s, Lōʻihi was not known to be active. Instead, it was thought to be one of the multitude of seamounts, extinct volcanoes that had sunk below the sea, stretching towards the northwest in the long streak of the Hawaiian-Emperor seamount chain. These dead volcanoes are thought to be between 80-100 million years old. The sea floor was created some 6,000 km (3,728 mi) away, on the undersea volcanic mountain chain known as the East Pacific Rise on a mid-oceanic ridge. It has slowly moved to its current location on the Hawaiian hotspot, and continues to move to this day. The age pattern of the craters confirms that the volcanism at Lōʻihi has slowly been moving east as Lōʻihi shifts away from its creator, the Hawaiʻi hotspot.

3D Rendering of the Seamount

Lōʻihi, like all of the Hawaiian volcanoes, follows an evolutionary pattern of development. Even though it measures 3,000 m (9,843 ft) high (taller than Mount St. Helens was prior to its 1980 eruption), it has yet to breach the surface of the ocean. The top of Lōʻihi currently lies 975 m (3,199 ft) beneath the waves. Lōʻihi represents a volcano in transition between pre-shield and shield volcano stage, providing valuable clues to the early development of Hawaiian volcanoes. Continued volcanism is expected to eventually build a new island platform at Lōʻihi. Estimates for sea level breach range from 10,000 to 100,000 years. After Lōʻihi reaches the surface, it will most likely merge with the island of Hawaiʻi, already composed of five separate volcanoes. Lōʻihi is the site of frequent landslides; growth has destabilized the volcano, and there are extensive areas of debris on the steep southeastern slope. Similar deposits from other Hawaiian volcanoes indicate that this is an important product of a Hawaiian volcano's early development.

Lōʻihi is built on a seafloor that slopes about five degrees. Its northern base is 1,900 m (6,200 ft) below sea level, but its southern base is a more substantial 4,755 m (15,600 ft) below the tide. Thus, the summit is 931 m (3,054 ft) above the seafloor as measured from the base of its north flank, but 3,786 m (12,421 ft) high when measured from the base of its southern flank.

Because Hawaiian volcanoes drift northwest at a rate of about 10 cm (3.9 in) a year, Lōʻihi must have formed 40 km (25 mi) southeast of its current position relative to the Poles.

Age and growth

Radiometric dating was used to determine the age of rock samples from Lōʻihi. The Hawaii Center for Volcanology tested rock samples brought back from various expeditions, notably the 1978 expedition, which provided a collection of 17 dredge samples. Most of the samples collected were found to be of ancient origin; the oldest dated rock is approximately 300,000 years old. Following the 1996 event, some young breccia was also collected. Based on the samples collected so far, scientists estimate that Lōʻihi is about 400,000 years old. Samples from the younger, eastern section (where there is volcanic activity) have been unreliably dated to between 4,000 to 21,000 years old. The rock accumulates at an average rate of 3.5 mm (0.14 in) per year near the base, and 7.8 mm (0.31 in) near the summit. If the data model from other volcanoes such as Kīlauea holds true for Lōʻihi, then 40% of the volcano's mass formed within the last 100,000 years. Assuming a linear growth rate, Lōʻihi would be 250,000 years old. However, as with all hotspot volcanoes, Lōʻihi's level of activity increases with time; therefore it would take at least 400,000 years for such a volcano to reach Lōʻihi's mass.

Activity

Lōʻihi is a young and fairly active volcano, though not as active as the nearby Kīlauea. In the last few decades, several earthquake swarms (an event that precedes volcanic eruptions) have been attributed to Lōʻihi, the greatest of which are summarized in the table below. The volcano has been known to be active since before scientific records of its activity was started, in 1959.

Most earthquake swarms at Lōʻihi last under 2 days; the two exceptions are the 1991-92 quake, lasting several months, and the 1996 event, which was shorter but much more powerful. Both of the quakes followed a pattern of activity beginning on the flank, then migrating to the summit. The 1996 event was directly observed by an autonomous Ocean-Bottom unit (OBO), allowing scientists to calculate the depth of the quakes, 6 km (4 mi) to 8 km (5 mi) below the summit, about the position of Lōʻihi's extremely shallow magma chamber.

Low-level seismic activity has been documented on Lōʻihi since March 1952. Typical numbers are between 2 and 10 earthquakes a month that can be traced to the seamount. Earthquake swarm data has been used to analyze Lōʻihi's velocity structure (how well it conducts seismic waves) and to investigate the relationship between earthquakes and eruptions. This low level of activity is periodically punctured by large swarms of earthquakes, some with hundreds at a time; interestingly, the majority of the quakes are not distributed close to the summit, though they follow a north-south trend. Most of the quakes occur in the southwest portion of Lōʻihi. The largest swarms that have occurred since records were set up took place on Lōʻihi in 1971, 1972, 1975, 1991-92 and 1996. Of these only one, in 1996, is confirmed to have escalated into a full-blown volcanic eruption; the possibility that several other events reached this state has been speculated. The nearest seismic station is about 30 km (19 mi) from Lōʻihi, on the south coast of Hawaii. Seismic events that have a magnitude under 2 are often recorded, but their location cannot be determined precisely, as it can be for larger events. In fact, the HUGO (Hawaii Undersea Geological Observatory) positioned on Lōʻihi detected 10 times the amount of quakes that were to be found on the HVO seismic network.

1996 event

Major Events

Year(s) Summary 1996 First directly observed confirmed eruption by a Hawaiian seamount. Started on February 25 1996 and lasted until August 9 1996. See the section "1996 Event" for more information. 1991 An OBO positioned on the seamount to track a recent earthquake swarm collected evidence of deflation, possibly due to magma withdrawal. 1986 Possible eruption, occurred on September 20 1986 (one day). 1984-85 Nine events of magnitude 3 or greater measuring between 3.0 to 4.2 were recorded. From November 11th 1984 to January 21 1985. Eruption possible, but uncertain. 1975 Prominent earthquake swarm from August 24 1975 to November 1975. Eruption uncertain. 1971-72 Eruption in September 1972, starting on September 17 1971 Eruption uncertain. 1952 An earthquake swarm on Loihi in 1952 was the event that first brought attention to the volcano, previously thought extinct. 50 BC ± 1000 Confirmed ancient eruption. 5050 BC ± 1000 Confirmed ancient eruption. 7050 BC ± 1000 Confirmed ancient eruption, most likely on the East flank. This table indexes only possible volcanic eruptions and major events. Lōʻihi has also been the site of multiple earthquake swarms occurring on a nearly semi-annual basis.

Black smokers of the type found on Lōʻihi.

By far the most amount of activity coming from Lōʻihi occurred in 1996. An earthquake swarm numbering about 4,000 occurred between July 16th and August 9th, 1996. This show of strength was the largest swarm of earthquake activity generated by a volcano at any Hawaiian volcano, lasting about two months in the summer of 1996. A total of 4,070 earthquakes were recorded by the Hawaii Volcano Observatory (HVO) network and confirmed by scientists at the University of Hawaiʻi, the first ever confirmation of an active eruption by a Hawaiian seamount. A total of about 40 earthquakes measuring between magnitudes 4 and 5 were also referenced by the worldwide seismic network.

The 1996 event was the first ever directly observed eruption of an undersea volcano in Hawaiʻi, and thus provided valuable clues to the nature of underwater volcanism. Because a full-blown eruption could cause a dangerous tsunami, it was important to investigate their risk. A method for monitoring the volcano was studied, and a solution was later found in HUGO. The volcano also offered a rare chance to study specimens of iron-oxidizing bacteria, a poorly understood but important part of the underwater ecosystem.

The eruption itself occurred over a period of two weeks, and was most directly observed by a quick response cruise that was launched soon after the volcano erupted. The National Science Foundation funded an expedition by University of Hawaiʻi scientists and began investigating the event and its origin in August 1996, led by Frederick Duennebier. Their assessment laid the groundwork for the many of the expeditions that followed. Follow-up expeditions to Lōʻihi also took place, including a series of manned-submersible dives in August and September. These were supplemented by a significant amount of shore-based research. From fresh rock collected during the expedition, it was learned that the eruption had occurred before the earthquake swarm.

These quick response dives in August were followed by NOAA-funded research in September and October of that year. Investigators included Gary McMurtry, Francis Sansone, Alexander Malahoff, and James Cowen. New dives were needed to reveal the extent of the damage done. These more detailed studies found that the southern portion of Lōʻihi's summit had collapsed, a result of a swarm of earthquakes and rapid withdrawal of magma from the system. A crater 1 km (0.62 mi) across and 300 m (984 ft) deep formed out of the rubble. The event involving the movement of 100 million cubic meters of volcanic material. A total of 4 to 5 square miles of the summit was altered. The area was populated by bus-sized pillow lava blocks, precariously perched along the outer rim of the newly formed crater. "Pele's Vents," an area on the southern side, previously considered stable, had collapsed completely into a giant pit, aptly renamed "Pele's Pit." Seawater was flowing down into the newborn pit on the northern end of the volcano, mixing with loose minerals and bacterial matter before flowing out over Lōʻihi's western edge. The resulting strong current made submersible diving hazardous in the region.

The studies were continually met by clouds of sulfide and sulfate. The sudden collapse of Pele's Vents had caused a large discharge of hydrothermal material and its sulfide. The presence of certain indicator minerals in the mixture indicated temperatures exceeding 250°C, a record. Most strikingly, the composition of the materials was similar to that of black smokers, the hydrothermal vent plumes located along Mid-Ocean Ridges that are a habitat for archea extremophiles. Samples from mounds built by discharges from the hydrothermal plumes, meanwhile, resembled white smokers. Dissolution and oxidation of the mineral observed over the two years following suggest that the sulfate is not easily preserved.

In the study it also was learned that the most volcanically and hydrothermicly active area was along the southern rift. Dives on the less active northern rim showed a more stable terrain, and high lava columns were still standing upright. A new hydrothermal vent field (Naha Vents) was also found, at a depth of 1,325 m (4,347 ft)

Recent activity

After the 1996 event, Lōʻihi has remained largely quiet. The intermission carried from 2002 to 2004. In 2005, the seamount showed signs of life again by sending a temblor bigger than any previously recorded. USGS-ANSS (Advanced National Seismic System) reported two quakes, magnitudes 5.1 and 5.4, on May 13 and July 17. Both originated from a depth of 44 km (27 mi). On April 23, a magnitude 4.3 quake was recorded at a depth of approximately 33 km (21 mi). Between late 2005 and early 2006, a swarm of about 100 quakes, the largest measuring 4 on the Richter scale and 12 km (7 mi) to 28 km (17 mi) deep, lasted from December 7, 2005 to January 18, 2006. Another earthquake measuring 4.7 was later recorded roughly midway between Lōʻihi and Pāhala (on the South Coast of the Main Island).

Exploration

Early work

Lōʻihi's first appearance was on Survey Chart 4115, a bathymetric rendering of part of Hawaiʻi, compiled by the US Coast and Geodetic Survey in 1940. At the time, the seamount was unnotable, as it is one of many in the region. It was a large earthquake swarm that first brought attention to the seamount, in 1952. That year, geologist Gordan A. Macdonald first hypothesized that the seamount was an active submarine shield volcano, similar to the two active Hawaiian volcanoes, Mauna Loa and Kīlauea. Macdonald's hypothesis made out the seamount as the newest volcano in the Hawaiian-Emperor seamount chain, created by the Hawaiʻi hotspot. However, because the quakes were oriented east-west (the direction of the volcanic fault) and there was no volcanic tremor in seismometers relatively far from the seamount, Macdonald attributed the earthquake to faulting rather then a true volcanic eruption.

Geologists suspected the seamount could be an active undersea volcano, but without evidence the idea remained largely speculative. The volcano was largely ignored after the 1952 event, and was often mislabeled as an "older volcanic feature" in subsequent charts. Geologist Kenneth O. Emery is credited with naming the seamount in 1955, describing the long and slender shape of the volcano as Lōʻihi, the Hawaiian word for "long".

In 1970, an expedition was formed to study intense, repeated seismic activity known as earthquake swarms in and around the Lōʻihi area. Rather than finding an old, dead seamount, data collected revealed that Lōʻihi was a young, possibly active volcano. Observations showed that the volcano is encrusted with young and old lava flows and is actively venting hydrothermal fluids.

R/V (research vessel) Kaʻimikai-o-Kanaloa (KoK) launching Pisces V, a battery-powered submersible. The R/V KoK is the support ship for the Hawaiʻi Undersea Research Laboratory (HURL)

In 1978, a US Geological Survey research ship collected dredge samples and photographed Lōʻihi's summit with the goal of studying whether or not Lōʻihi is active. Analysis of the photos and testing of pillow lava rock samples appeared to show that the material was "fresh," yielding more evidence that Lōʻihi was still active. An expedition from October 1980 to January 1981 collected further dredge samples and photographs, providing additional confirmation that Lōʻihi was alive. Studies indicated that the eruptions came from the southern part of the rift crater. This area is closest to the Hawaiʻi hotspot, the feature supplying Lōʻihi with lava. An autonomous observatory was positioned on Lōʻihi in 1991 to track an earthquake swarm.

Following a 1986 seismic event, a network of five OBOs were deployed on Lōʻihi for a month. Lōʻihi's rampid and reliable seismology makes it an ideal candidate for seismic study through OBOs. In 1987, the famous submersible DSV Alvin investigated Lōʻihi.

1996 to present

The bulk of Lōʻihi dives comes from dives made in response to the 1996 eruption. In a dive conducted almost immediately after seismic activity was reported, visibility was greatly reduced by high concentrations of displaced minerals and large floating mats of bacteria in the water. The bacteria, which feed on the dissolved nutrients, have already begun colonizing the new hydrothermal vents at Pele's Pit (formed from the collapse of the old ones), and may be indicators of the kinds of material ejected from the newly formed vents. They were carefully sampled for further analysis in a laboratory. An OBO briefly sat on the summit before a more permanent probe could be installed.

Repeated multibeam bathymetric mapping were used to measure the exact changes in the summit following the 1996 collapse. Hydrothermal plume surveys confirmed changes in the energy and dissolved minerals emanating from Lōʻihi. HURL's 2,000 m (6,562 ft) capable submersible Pisces V allowed scientists to sample the vent waters, microorganisms, and hydrothermal mineral deposits.

Ocean Bottom Observatory (OBO) at Pele's Vents

In 1997, scientists from the University of Hawaiʻi installed a submarine observatory, scientifically named "Ocean Bottom Observatory," (OBO) on the summit of Lōʻihi Seamount. The machine was nicknamed "HUGO," (Hawaiʻi Undersea Geological Observatory). HUGO was connected to the shore, 34 km (21 mi) away, by a long fiber optic cable. It gave scientists real-time seismic, chemical and visual information about the state of Lōʻihi, which had by then become an international laboratory for the study of undersea volcanism. The cable that provided HUGO with power and communications broke in October 1998, effectively shutting it down. On January 19 of the following year, HUGO was visited by Pisces V. It was discovered that a junction box regulating the flow of power to the observatory had been flooded with seawater. The failed portion was successfully repaired, and a new hydrophone was installed. The first new recording to reach the listening station at Honuapo was that of a whale's song, but the volcano itself remained quiet. Divers noted that HUGO's junction box was half-buried in volcanic mud, which should have helped keep it stable for many years to come. The observatory carried on for 4 more years before it went dead again in 2002. University of Hawaiʻi's Fred Duennebier, the developer of HUGO and leader of many of the expeditions, expects to see it back on Lōʻihi in the future, after improvements are made and the line is protected with steel armor. However, reinstalling was canceled, and the materials would most likely have gone into anther probe. This is because the only permanent fix for the breakages is to cover the cable in steel armor, which was deemed too expensive (the cable was donated by AT&T). Improvements were later made to the cable, and it might be placed back on Lōʻihi someday.

Since 2006 the Fe-Oxidizing Microbial Observatory Project (shorthand FeMO), funded by the National Science Foundation and Microbial Observatory Program, has led cruises to Lōʻihi to investigate its microbiology, every October. The first cruise, on the ship R/V Melville and exploiting the submersible JASON2, lasted from September 22 to October 9. In particular, these cruises study the large number of Fe-Oxidizing Bacteria that have colonized Lōʻihi. Lōʻihi's extensive vent system is characterized by a high concentration of CO2 and Iron, while being low in sulfide. These characteristics make a perfect environment for iron-oxidizing bacteria, called FeOB, to thrive in, and for this reason it was chosen as the research site for FeMO. Much of what is known about Fe-Oxidizing Bacteria comes from the FeMO expeditions.

Expedition timeline

Date	Study (most on R/V Kaʻimikai-o-Kanaloa and with Pisces V)
1940	Lōʻihi's first appearance was on Survey Chart 4115, compiled by the US Coast and Geodetic Survey in 1940.
1978	An expedition formed to study intense seismic activity in the region at the time. Data collected was the first solid evidence towards the volcano being active.
1979	More extensive sampling (17 dredgehauls) from this expedition seemed to confirm the 1970 results.
1980	Extensive hydrothermal fields found, yielding more evidence. First high-resolution bathymetric mapping.
August 1996	Emergency response team dives reacting to extensive activity, led by Frederick Duennebier.
Early Sept. 1997	Studies of Hydrothermal vents (Batiza and McMurtry, Chief Scientists).
Late August 1997	Geological studies of recent eruptions at Lōʻihi (Garcia and Kadko, Chief Scientists)
October 1997	HUGO Deployment (Frederick Duennebier, Chief Scientist)
September-October 1998	Series of Dives by multiple Science Parties to visit the New Pit, Summit Area and HUGO
January 1998	HUGO Revisit (Frederick Duennebier, Chief Scientist)
October 2002	HUGO recovered from sea bottom
October 2006 October 2007 October 2008	FeMO - Fe-Oxidizing Microbial Observatory - cruises to investigate Fe-Oxidizing Microbial Bacteria at Lōʻihi. Much is learned about Lōʻihi's microbial community.
October 2009	Scheduled FeMO cruise, currently in planning.

Ecology

Microorganisms

Lōʻihi's mid-Pacific location and its well-sustained hydrothermal system contribute to a rich oasis for a unique microbial ecosystem. Areas of extensive hydrothermal venting are found on Lōʻihi's crater floor and north slope, and along the summit of Lōʻihi itself.

Bacterial mat on a 160 °C vent. Inset shows micrograph of bacteria.

Bacterial mats above active hydrothermal vents at the base of Pele's Pit.

Active hydrothermal vents were first discovered at Lōʻihi in the late 1980s. These vents are remarkably similar to those found at the mid-ocean ridges, with similar composition and thermal differences. The two most prominent vent fields are at the summit and named Pele's Pit (formally Pele's Vents) and Kapos Vents, after the Hawaiian deities Pele (deity) and Namakaokahai, who according to local legend chased each other from island to island. These vents were considered as "low temperature vents" by the scientific community as their waters were only about 30°C. The eruption of 1996 and the creation of Pele's Pit changed this. High temperature venting had initiated, and exit temperatures was measured at 77 °C in 1996. Because of safety concerns, the inner vent temperatures were not found until September 1997. The vents are 1,100 m (3,600 ft) to 1,325 m (4,347 ft) below the surface, and range in temperature from 10 to 167° Celsius. The vent fluids are characterized by a high concentration of CO
₂ (up to 17 mM) and Fe (Iron), but low in sulfide. Low oxygen and pH levels are important factors in supporting the high amounts of Fe (iron), one of the hallmark features of Lōʻihi. These characteristics make a perfect environment for iron-oxidizing bacteria, called FeOB, to thrive in.

A diverse community of microbial mats surround the vents and virtually cover Pele's Pit. The Hawaiʻi Undersea Research Laboratory (HURL), NOAA's Research Center for Hawaiʻi and the West Pacific, monitors and researches the hydrothermal systems and studies the local community. The National Science Foundation (NSF) funded a extremophile sampling expedition to Lōʻihi in 1999. Microbial mats surrounded the 160°C vents, and included a never before seen jelly-like organism. Samples were collected for study at NSF's Marine Bioproducts Engineering Center (MarBEC). In 2001, Pisces V collected samples of the organisms and brought them to the surface for study.

Currently, NOAA's National Undersea Research Center (HURL) and NSF's Marine Bioproducts Engineering Center (MarBEC) are cooperating to sample and research the local bacteria and archea extremophiles. There are also FeMO (Fe-Oxidizing Mircobial Observatory) cruises in planning for October 2009.

Macroorganisms

Number of species	Breakdown of distribution range
22 Species	Common (mostly larger sharks, lutjanids, and carangids)
66 Species	Indo-Pacific
64 Species	Pacific
54 Species	Hawaiian Archipelago (including Johnston Atoll and Cross Seamount)
4+ Species	Species newly recorded to be present at Hawaiʻi (including Johnston Atoll and Cross Seamount)

Marine life inhabits Lōʻihi, although it is not as common as life at other, less active seamounts. Two common species of fish found living near Lōʻihi are the Celebes monkfish (Sladenia remiger) and members of the Cutthroat eel family (actually a fish), Synaphobranchid. Also common were the bresiliid shrimp Opaepele lōʻihi (described in 1995), and the pogonophoran worm. The post-1996 event dives, however, found no evidence for either the shrimp or the worm, and the impact of the event on these species is unknown.

In 1982, two expeditions to Lōʻihi Seamount, Johnston Atoll and Cross Seamount photographed more than 250 fish types at depths between 40 m (131 ft) and 2,000 m (6,562 ft). A total of 213 fish species were identified, most of which were found on hard surfaces such as ledges and coves. There was a rapid decrease in the number of species from the depths of 200 m (656 ft) to 400 m (1,312 ft). 108 species were seen deeper then previously recorded, and 11 were found some 20 m (66 ft) shallower then previously reported. Loihi doe not appear to be divided into any Faunal zones. Species newly recorded in Hawaiʻi include Bathypterois grallator (Tripod fish), Bodianus cylindriatus (Labrid fish), Centrophorus granulosus (Gulper shark), Chaunax fimbriatus (Tassled coffinfish), Caelorinchus spilonotus (Rattail), Notocanthus (Spiny eel), Paratrachichthys prosthemius (Slimehead), Prognathodes guezei (Gueze's butterflyfish), and Sladenia remiger (Celebes monkfish). Other new species are Centrodraco rubellus, Epigonus glossodontus (Deepwater cardinalfish), and Pseudanthias fucinus. Caelorinchus and Callanthias are mostly undescribed.

Further reading

• Chave, E. H. (1998). In Deeper Waters: Photographic Studies of Hawaiian Deep-sea Habitats and Life-forms. University of Hawaiʻi Press. ISBN 0824820037. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Duennebier, F. K. (1997-06-03). "Researchers rapidly respond to submarine activity at Lōʻihi volcano, Hawaiʻi". EOS Trans. Am. Geophys. Union. 78: 229–233. doi:10.1029/97EO00150. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Emery, K.O. (1955). "Submarine topography south of Hawaiʻi". Pacific Science. 9. University of Hawaiʻi Press: 286–291.

• "Global Volcanism Program Data Sources". Global Volcanism Program. National Museum of American History.
• Klein, F. (1982). "Earthquakes at Lōʻihi submarine volcano and the Hawaiian hot spot". Journal of Geophysical Research. 87: B9. ISSN 0148-0227. {{cite journal}}: Cite has empty unknown parameter: |coauthors= (help)
• Macdonald, G.A. (1952). "The South Hawaiʻi Earthquakes of March and April, 1952." The Volcano Letter. U.S. Geological Survey Professional Paper 515.
• Malahoff, Alexander (1982-07-15). "Geology and chemistry of hydrothermal deposits from active submarine volcano Lōʻihi, Hawaiʻi". Nature. 298 (5871). Nature Publishing Group: 234–239. doi:10.1038/298234a0. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Malahoff, A. (Oct., 2002). "A seamless system for the collection and cultivation of extremophiles from deep-ocean hydrothermal vents". IEEE Journal of Oceanic Engineering. 27 (4). IEEE Oceanic Engineering Society: 862–869. doi:10.1109/JOE.2002.804058. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Moore, J.G. (Feb., 1982). "Diverse basalt types from Lōʻihi Seamount, Hawaiʻi". Geology. 10 (2). Geological Society of America: 88–92. doi:10.1130/0091-7613(1982)10. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |doi_brokendate= ignored (|doi-broken-date= suggested) (help)
• Scripps Institution of Oceanography. (2002). Benthic Invertebrate Collection Database.

External links

• Hawaiʻi Center for Volcanology, University of Hawaiʻi.
• Lōʻihi Seamount — USGS website.
• Lōʻihi Submarine Volcano: A unique, natural extremophile laboratory — NOAA research site.
• 2001 Lōʻihi Seamount Exploration Homepage of the 2001 Lōʻihi Seamount Exploration
• Recent Activity