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Research about Papua New Guinea

Source-linked reports with geographic coverage including Papua New Guinea.

10 recordsLinked to original sources
USGS2021

Effects of low pH on the coral reef cryptic invertebrate communities near CO2 vents in Papua New Guinea

Small cryptic invertebrates (the cryptofauna) are extremely abundant, ecologically important, and species rich on coral reefs. Ongoing ocean acidification is likely to have both direct effects on the biology of these organisms, as well as indirect effects through cascading impacts on their habitats and trophic relationships. Naturally acidified habitats have been important model systems for studying these complex interactions because entire communities that are adapted to these environmental conditions can be analyzed. However, few studies have examined the cryptofauna because they are difficult to census quantitatively in topographically complex habitats and are challenging to identify. We addressed these challenges by using Autonomous Reef Monitoring Structures (ARMS) for sampling reef-dwelling invertebrates >2 mm in size and by using DNA barcoding for taxonomic identifications. The study took place in Papua New Guinea at two reef localities, each with three sites at varying distances from carbon dioxide seeps, thereby sampling across a natural gradient in acidification. We observed sharp overall declines in both the abundance (34–56%) and diversity (42–45%) of organisms in ARMS under the lowest pH conditions sampled (7.64–7.75). However, the overall abundance of gastropods increased slightly in lower pH conditions, and crustacean and gastropod families exhibited varying patterns. There was also variability in response between the two localities, despite their close proximity, as one control pH site displayed unusually low diversity and abundances for all invertebrate groups. The data illustrate the complexity of responses of the reef fauna to pH conditions, and the role of additional factors that influence the diversity and abundance of cryptic reef invertebrates.

Milne Bay Province↗
USGS2021

Evaluating the state-of-the-art in remote volcanic eruption characterization Part II: Ulawun volcano, Papua New Guinea

Retrospective eruption characterization is valuable for advancing our understanding of volcanic systems and evaluating our observational capabilities, especially with remote technologies (defined here as a space-borne system or non-local, ground-based instrumentation which include regional and remote infrasound sensors). In June 2019, the open-system Ulawun volcano, Papua New Guinea, produced a VEI 4 eruption. We combined data from satellites (including Sentinel-2, TROPOMI, MODIS, Himawari-8), the International Monitoring System infrasound network, and GLD360 globally detected lightning with information from the local authorities and social media to characterize the pre-, syn - and post-eruptive behaviour. The Rabaul Volcano Observatory recorded ~24 h of seismicity and detected SO 2 emissions ~16 h before the visually-documented start of the Plinian phase on 26 June at 04:20 UTC. Infrasound and SO 2 detections suggest the eruption started during the night on 24 June 2019 at 10:39 UTC ~38 h before ash detections with a gas-dominated jetting phase. Local reports and infrasound detections show that the second phase of the eruption started on 25 June 19:28 UTC with ~6 h of jetting. The first detected lightning occurred on 26 June 00:14 UTC, and ash emissions were first detected by Himawari-8 at 01:00 UTC. Post-eruptive satellite imagery indicates new flow deposits to the south and north of the edifice and ash fall to the west and southwest. In particular, regional infrasound data provided novel insight into eruption onset and syn -eruptive changes in intensity. We conclude that, while remote observations are sufficient for detection and tracking of syn-eruptive changes, key challenges in data latency, acquisition, and synthesis must be addressed to improve future near-real-time characterization of eruptions at minimally-monitored or unmonitored volcanoes.

Bismark volcanic arc, New Britain Island, Ulawun v↗
USGS2020

The 1951 eruption of Mount Lamington, Papua New Guinea: Devastating directed blast triggered by small-scale edifice failure

The catastrophic explosion of Mount Lamington volcano, Papua New Guinea on January 21, 1951 produced a devastating pyroclastic density current (PDC) that knocked down dense tropical rainforest over an area of 230 km 2 and killed approximately 3000 people. We present results of a field reinvestigation of the 1951 PDC deposit combined with an analysis of the available photographs and eyewitness accounts of the eruption first published in the fundamental work of G. A. M. Taylor (1958). We have concluded that the six-days-long pre-climactic activity before the 1951 eruption (which included felt local seismicity, frequent ash-laden explosions of vulcanian type, bulging of the volcano slope accompanied with landslides) was associated with shallow-level intrusion of a highly viscous magma body (cryptodome/dome) of andesitic composition with a volume of approximately 0.01 km 3 . This intrusion destabilized Mount Lamington's prehistoric intra-crater lava dome. On January 21 the destabilized dome gravitationally collapsed and produced a relatively small-volume debris avalanche, the deposit of which was not recognized during Taylor's original investigation. The debris avalanche had a volume of approximately 0.02–0.04 km 3 , travelled a distance (L) of 8.5 km and had the ratio of vertical drop (H) to runout (L) of 0.14. The edifice collapse decompressed the intruding cryptodome and triggered its explosive fragmentation. Photographs of the climactic explosion show that the eruptive cloud initially rose vertically but subsequently collapsed upon the terrain around the vent, and formed a PDC which flowed radially outward. The enhanced northward propagation of the PDC to a maximum distance of 13 km reveals that the northern breach in the ancient crater's high walls influenced the distribution of the deposit. In the studied NE-N-NW sector of the devastated area, in the zone proximal to the volcano, the PDC emplaced a normally graded layer of coarse ash and lapilli mixed in the base with picked-up soil and plant fragments. The layer gradually becomes thinner and finer-grained with distance from the volcano. The PDC deposit has a volume of approximately 0.025 km 3 and consists of approximately 80% juvenile rock fragments derived from the explosively fragmented cryptodome. The remaining 20% consists of accidental clasts derived from the old volcanic edifice. The juvenile material is crystal-rich andesite with a unimodal vesicularity distribution (4 to 36%). The reconstructed eruption sequence, the PDC tree blowdown pattern and characteristics of the PDC deposit are similar to those of catastrophic laterally-directed blasts of volcanoes Bezymianny in 1956, Mount St.Helens in 1980, and Soufriere Hills, Montserrat in 1997. In contrast to the cases of these “classic” lateral blasts, the blast cloud of Lamington was initially vertically-directed before collapsing to produce a PDC. We speculate that the climactic explosion of Mount Lamington was initially vertical because the rupture surface of the triggering sector collapse intersected the apex of the intruding cryptodome (it exposed a subhorizontal surface of the cryptodome apex), while at Bezymianny, Mount St.Helens, and Soufriere Hills the rupture intersected the main body of the cryptodome/dome, and exposed their steeply inclined surfaces.

Journal of Volcanology and Geothermal Research↗
USGS2017

Four new species of Eimeria (Apicomplexa: Eimeriidae) from Emoia spp. Skinks (Sauria: Scincidae), from Papua New Guinea and the Insular Pacific

Between September and November 1991, 54 adult skinks from 15 species were collected by hand or blowpipe from several localities on Rarotonga, Cook Islands, Ovalau Island, Fiji, and Papua New Guinea (PNG), and their feces were examined for coccidians. Species included 5 seaside skinks ( Emoia atrocostata ), 1 Pacific blue-tailed skink ( Emoia caeroleocauda ), 2 Fiji slender treeskinks ( Emoia concolor ), 15 white-bellied copper-striped skinks ( Emoia cyanura ), 1 Bulolo River forest skink ( Emoia guttata ), 6 dark-bellied copper-striped skinks ( Emoia impar ), 5 Papua five-striped skinks ( Emoia jakati ), 2 Papua slender treeskinks ( Emoia kordoana ), 3 Papua robust treeskinks ( Emoia longicauda ), 1 brown-backed forest skink ( Emoia loveridgei ), 3 Papua black-sided skinks ( Emoia pallidiceps ), 2 Papua white-spotted skinks ( Emoia physicae ), 2 Papua yellow-head skinks ( Emoia popei ), 1 Papua brown forest skink ( Emoia submetallica ), and 5 Fiji barred treeskinks ( Emoia trossula ) Species of Eimeria ( Ei .) were detected from these Emoia ( Em .) spp. and are described here as new. Oocysts of Eimeria iovai n. sp. from Em. pallidiceps from PNG were ellipsoidal with a bilayered wall (L × W) 26.5 × 18.1 μm, with a length/width ratio (L/W) of 1.1. Both micropyle and oocyst residuum were absent, but a fragmented polar granule was present. This eimerian also was found in Em. atrocostata from PNG. Oocysts of Eimeria kirkpatricki n. sp. from Em. atrocostata from PNG were ellipsoidal with a bilayered wall, 18.6 × 13.5 μm, L/W 1.4. A micropyle and oocyst residuum were absent, but a fragmented polar granule was present. This eimerian was also shared by Em. cyanura from the Cook Islands and Fiji, Em. impar from the Cook Islands, Em. loveridgei from PNG, Em. pallidiceps from PNG, Em. popei from PNG, and Em. submetallica from PNG. Oocysts of Eimeria stevejayuptoni n. sp. from Em. longicauda were subspheroidal to ellipsoidal with a bilayered wall, 18.7 × 16.6 μm, L/W 1.1. A micropyle and oocyst residuum were absent, but a fragmented polar granule was present. Oocysts of Eimeria emoia n. sp. from Em. longicauda from PNG were cylindroidal with a bilayered wall, 29.2 × 15.7 μm, L/W 1.9. A micropyle and oocyst residuum were absent, but a polar granule was present. These are the first eimerians reported from Emoia spp. and they add to our growing knowledge of the coccidian fauna of scincid lizards of the South Pacific.

Insular Pacific↗
USGS2014

Four new species of coccidia (Apicomplexa: Eimeriidae) from Owen Stanley Skinks, Papuascincus stanleyanus (Sauria: Scincidae), from Papua New Guinea

Between September and November 1991, 12 Owen Stanley skinks, Papuascincus stanleyanus (Booulenger) were collected from various localities on Papua New Guinea and examined for coccidians. Six (50%) were found to harbour four eimerians that we describe here as new. Oocysts of Eimeria burseyi sp. n. were elongate to ellipsoidal with a bilayered wall and measured (length x width, L x W) 36.0 x 24.0 microm, with a L/W ratio of 1.5. Both micropyle and oocyst residuum were absent, but a polar granule was present. Oocysts of Eimeria goldbergi sp. n. were ellipsoidal, with a bilayered wall, and measured 21.4 x 16.1 microm; L/W ratio was 1.3. Both micropyle and oocyst residuum were absent, but a single or fragmented polar granule was present. Oocysts of Eimeria boulengeri sp. n. were spheroidal to slightly subspheroidal, with a thin, single-layered wall that readily collapses, and measured 16.0 microm, L/W ratio was 1.0. Both micropyle and oocyst residuum were absent, but usually one (sometimes two) polar granule(s) were present. Oocysts of Eimeria niuginiensis sp. n. were oblong to tapered with a bilayered wall, and measured 20.0 x 13.1 microm; L/W ratio was 1.5. A micropyle, oocyst residuum and polar granule were absent. To our knowledge, these represent the only coccidians ever described from P. stanleyanus.

Folia Parasitologica↗
USGS2012

A preliminary assessment of the Nactus pelagicus species group (Squamata: Gekkonidae) in New Guinea and a new species from the Admiralty Islands

The Slender-toed Geckos ( Nactus ) currently have four recognized species in New Guinea, and these species divide into two sister clades: a pelagicus clade and a vankampeni clade (Heinicke et al. 2010). The latter contains three dwarf species. The former consists of five bisexual populations, of which numerous New Guinea populations are uncharacterized nomenclaturally and lumped under the epithet ‘ pelagicus .’ This report and description of a new species of the pelagicus group from Manus Island in the Admiralty Islands encourages us to offer a preliminary assessment of morphology and diversity in New Guinea ‘ pelagicus ’ populations.

Admiralty Islands↗
USGS2011

Geochemistry of hydrothermal fluids from the PACMANUS, Northeast Pual and Vienna Woods hydrothermal fields, Manus Basin, Papua New Guinea

Processes controlling the composition of seafloor hydrothermal fluids in silicic back-arc or near-arc crustal settings remain poorly constrained despite growing evidence for extensive magmatic–hydrothermal activity in such environments. We conducted a survey of vent fluid compositions from two contrasting sites in the Manus back-arc basin, Papua New Guinea, to examine the influence of variations in host rock composition and magmatic inputs (both a function of arc proximity) on hydrothermal fluid chemistry. Fluid samples were collected from felsic-hosted hydrothermal vent fields located on Pual Ridge (PACMANUS and Northeast (NE) Pual) near the active New Britain Arc and a basalt-hosted vent field (Vienna Woods) located farther from the arc on the Manus Spreading Center. Vienna Woods fluids were characterized by relatively uniform endmember temperatures (273–285 °C) and major element compositions, low dissolved CO 2 concentrations (4.4 mmol/kg) and high measured pH (4.2–4.9 at 25 °C). Temperatures and compositions were highly variable at PACMANUS/NE Pual and a large, newly discovered vent area (Fenway) was observed to be vigorously venting boiling (358 °C) fluid. All PACMANUS fluids are characterized by negative δ D H 2 O "> δDH 2 O values, in contrast to positive values at Vienna Woods, suggesting substantial magmatic water input to circulating fluids at Pual Ridge. Low measured pH (25 °C) values (∼2.6–2.7), high endmember CO 2 (up to 274 mmol/kg) and negative δ 34 S H 2 S "> δ 34 S H2 S values (down to −2.7‰) in some vent fluids are also consistent with degassing of acid-volatile species from evolved magma. Dissolved CO 2 at PACMANUS is more enriched in 13 C (−4.1‰ to −2.3‰) than Vienna Woods (−5.2‰ to −5.7‰), suggesting a contribution of slab-derived carbon. The mobile elements (e.g. Li, K, Rb, Cs and B) are also greatly enriched in PACMANUS fluids reflecting increased abundances in the crust there relative to the Manus Spreading Center. Variations in alkali and dissolved gas abundances with Cl at PACMANUS and NE Pual suggest that phase separation has affected fluid chemistry despite the low temperatures of many vents. In further contrast to Vienna Woods, substantial modification of PACMANUS/NE Pual fluids has taken place as a result of seawater ingress into the upflow zone. Consistently high measured Mg concentrations as well as trends of increasingly non-conservative SO 4 behavior, decreasing endmember Ca/Cl and Sr/Cl ratios with increased Mg indicate extensive subsurface anhydrite deposition is occurring as a result of subsurface seawater entrainment. Decreased pH and endmember Fe/Mn ratios in higher Mg fluids indicate that the associated mixing/cooling gives rise to sulfide deposition and secondary acidity production. Several low temperature (⩽80 °C) fluids at PACMANUS/NE Pual also show evidence for anhydrite dissolution and water–rock interaction (fixation of B) subsequent to seawater entrainment. Hence, the evolution of fluid compositions at Pual Ridge reflects the cumulative effects of water/rock interaction, admixing and reaction of fluids exsolved from silicic magma, phase separation/segregation and seawater ingress into upflow zones.

Manus Basin↗
USGS2000

Origin of the 17 July 1998 Papua New Guinea tsunami: Earthquake or landslide

The tsunami that struck Papua New Guinea on 17 July 1998 shortly after a M w 7.0 earthquake ( Figure 1 ) was one of the deadliest tsunamis in this century. At least 2,200 people died from this event, essentially destroying an entire generation in some communities. In the months following the tsunami, several international survey teams collected data in an attempt to better understand the cause of this event. Elevations of waterline marks and displaced debris measured by the first International Tsunami Survey Team (ITST; Kawata et al., 1999 ) indicated an average runup of 10 m occurring over a 25 km length of coastline in the vicinity of Sissano Lagoon ( Figure 2 ). The maximum runup from this event was approximately 15 m. Tsunami runup heights of this size are commonly associated either with earthquakes of much larger magnitude or with “tsunami earthquakes” as defined by Kanamori ( 1972 ) and later discussed by Kanamori and Kikuchi ( 1993 ). Even for tsunami earthquakes, however, runup heights of 10-15 m seem only to occur for earthquakes M w > 7.5. Because these runup heights appear anomalously high for a M 7 earthquake, other sources have been postulated for the tsunami, including a submarine landslide or mass flow. Earlier this year, the bathymetry north of Papua New Guinea was surveyed by the Japan Marine Science and Technology Center (JAMSTEC) and the South Pacific Applied Geoscience Commission (SOPAC). In a report describing the preliminary results from these cruises ( Tappin et al. , 1999 ), bathymetric images are presented that show evidence both of a 40-km-long fault scarp and of collapse features within an approximately 10-km-wide bathymetric amphitheater ( Figure 2 ). The report suggests that a landslide was the sole cause for the tsunami. In this paper, I revisit the common assumption that local tsunami runup scales directly with moment magnitude and demonstrate that the tsunami generated by the earthquake cannot be disregarded to explain the runup observations.

Seismological Research Letters↗