Gulf Province Research Articles

Late Pleistocene Bryant Canyon turbidite system: Implications for Gulf of Mexico minibasin petroleum systems

The western ancestral Mississippi shelf-margin delta fed the Bryant Canyon turbidite system in the intraslope basin province of the northwestern Gulf of Mexico (GOM) during the penultimate glacial lowstand of sea level (130–160 year BP). The Bryant Canyon links a chain of 15 fill-and-spill minibasins on the continental slope. On the upper and lower continental slopes, minibasins are narrow (1–3 km), elongate (3–6 km), and follow salt ridges. On the middle slope, minibasins are larger (8–15 km) semicircular basins. Three main depositional facies are recognized based on seismic-facies interpretation: (1) ponded turbidites (T), (2) mass-transport deposits (MTDs), and (3) bypass channelized turbidites (C). Thick, intrabasinal, muddy MTD wedges sourced from high-relief internal walls of the minibasins alternate with and frequently cap externally derived deposits. Tabular extrabasinal MTD deposits originated from shelf-margin delta or canyon-wall failures upslope. The T and MTD facies deposits each make up approximately 40% of basin fill, and the C facies deposits comprise approximately 20%. The T facies deposits form perched lobes at canyon inlets into basins and ponded units on distal sides of basins. Channels in the C facies are similar in width (500–2000 m) and relief (20–100 ms) to channels in productive GOM subsurface minibasins. Syntectonic activity of salt diapirs typically began midway through filling of Bryant Canyon minibasins and then preferentially uplifted northern portions of basin deposits. Local salt-tectonic activity caused greater basin relief and thicker capping MTDs than in subsurface minibasins to the west (e.g., Brazos-Trinity Basin IV) or east (e.g., Mississippi Canyon). Bryant Canyon minibasins provide excellent modern analogs for subsurface Miocene to Pleistocene GOM chains of minibasins because of similar scales and depositional facies. The youngest Bryant T facies deposits and their overlying incised, thick, channel deposits contain the most sand-prone facies and suggest the best potential for petroleum reservoirs in subsurface minibasins.

The chronology of Popo, an ancestral village site in Orokolo Bay, Gulf Province, Papua New Guinea

ABSTRACTCultural research at Orokolo Bay (PNG) has long focussed on elaborate social-ceremonial practice and maritime exchange (hiri). Previously the chronology of settlement was based on a single radiocarbon determination of 410 ± 80 BP from Popo village. Today, Popo is an important village site along an ancestral migration route for clan groups living up to 125 km to the east. This paper presents archaeological results of a recent excavation at Popo, undertaken near the location of Rhoads’ earlier investigations in 1976. A statistically modelled chronology based on six newly obtained radiocarbon dates reveals occupation for this part of Popo between 13 and 455 cal. BP. These new results enable us to understand better the chronological history of this part of Orokolo Bay.

Nutritional status and dietary diversity of Kamea in Gulf Province, Papua New Guineas.

To assess the nutritional status of infants, children and non-pregnant women and underlying factors, dietary diversity and community food security, in the Kamea community in Gulf Province, Papua New Guinea. Prospective cross sectional study. Study population 69 infants (0-59 months), 151 children (6-12 years) and 79 non-pregnant women from 10 villages in Kotidanga Local Level Government, Kerema District, Gulf Province, Papua New Guinea. Among infants prevalence of moderate stunting, wasting and underweight were 38.9%, 8.3% and 44.4%, respectively; after adjusting Hb concentration for altitude, the anaemia prevalence was 53.8%. Among children prevalence of severe stunting was 21.2%; moderate stunting, wasting and underweight were 57.6%, 12.2% and 48.5%, respectively; anaemia was 30.3%; median urinary iodine concentration was 32.0 μg/L and iodine deficiency was prevalent among 88.1%. Among women, mean height, weight and BMI were 1.46±0.04 m, 43.9±5.91 kg and 20.4±2.32 kg/m2, respectively; low BMI (<18.5 kg/m2) and anaemia were prevalent among 22.8% and 35.4%, respectively; median urinary iodine concentration was 36.0 μg/L and iodine deficiency was prevalent among 80.3%. Exclusive breastfeeding was universal for young infants; complementary foods were limited in variety and frequency. Dietary diversity was limited, implementation of the universal salt iodisation strategy restricted and community food security was inadequate. The high prevalence of malnutrition and anaemia among the three age groups, including moderate status of iodine deficiency among women and children, are significant public health concerns. Improvements in dietary diversity, adequate use of iodised salt and community food security are needed.

Petrographic analyses of sand temper/inclusions in ceramics of Kikiniu, Kikori River and modern sand samples from the Gulf Province (Papua New Guinea)

ABSTRACTThe archaeological site of Kikiniu (a.k.a. Kulupuari) in the mid‐reaches of the Kikori River, Gulf Province (Papua New Guinea) contains a rich assemblage of ceramic sherds dating to 1550–1000 calBP. This is a region for which there is no ethnographic and no prior archaeological evidence of ceramic manufacture, but for which during the ethnographic period premade pottery vessels are well known to have been imported en masse from long‐distance seafarers from Yule Island and Port Moresby. Here we present initial petrographic analyses of sand temper/inclusions from 20 excavated sherds from Kikiniu, and 14 samples of modern beach and river sand collected across the area, to determine whether the Kikiniu ceramics could have been locally manufactured, and if not, from where they were imported. Our preliminary results confirm that the majority of the sherds, and possibly all, are from ceramics that were probably imported from manufacturing sites to the south‐east. Given that the Kikiniu region was then a rainforest, sago‐rich region, ceramics probably arrived at Kikiniu as part of the sago trade as far back as c.1550–1000 calBP.

Outcomes of singleton and twin breech deliveries in a ten year (2005 to 2014) retrospective audit at two rural hospitals in Papua New Guinea’s Gulf Province

&lt;p&gt;&lt;span style="text-decoration: underline;"&gt;Introduction&lt;/span&gt;&lt;em&gt; &lt;/em&gt;The aim of this audit was to investigate the rates of breech-related perinatal death and maternal and neo-natal morbidity in a resource-poor setting where caesarean sections are difficult to perform. &lt;span style="text-decoration: underline;"&gt;Method&lt;/span&gt;&lt;em&gt;. &lt;/em&gt;An audit of 5,102 babies born at two rural Papua New Guinean hospitals, Kapuna and Kikori, from 2005 to 2014 inclusive was performed. Information was gathered from the facility obstetric registers and supplemented by Kikori Hospital’s surgical register. During the period there were 179 breech presentations (103 singletons, 76 twins). The primary outcome was defined as perinatal death. Secondary outcomes were neonatal morbidity and maternal post-partum haemorrhage. Exclusion criteria were applied prior to analysis. These included: Likely pre-labour intrauterine death; mother presenting to hospital in second or third stage; baby born before arrival at hospital; prematurity recorded in the notes or birth weight less than 1500g as a surrogate marker; significant fetal abnormality; and significant maternal medical condition. &lt;span style="text-decoration: underline;"&gt;Findings&lt;/span&gt;&lt;em&gt;. &lt;/em&gt;The adjusted incidence of the outcomes were: Perinatal death for vaginal breech singletons 235/1,000 (95% CI 158-336/1,000) and vaginal breech twins 31/1,000 (95% CI 9-107/1,000); neonatal morbidity for vaginal breech singletons 141/1,000 (95% CI 82-231/1,000) and vaginal breech twins 31/1,000 (95% CI 9-107/1,000); post-partum haemorrhage for vaginal breech singletons 129/1,000 (95% CI 74-217/1,000) and vaginal breech twins 230/1,000 (95% CI 137-361/1,000). &lt;span style="text-decoration: underline;"&gt;Conclusions&lt;/span&gt;&lt;em&gt;. &lt;/em&gt;Poor outcomes for singleton vaginal breech delivery at the two hospitals were common. The potential in the rural setting for increased education on safe trial of vaginal breach delivery as well as increasing access to caesarean sections deserves consideration. &lt;/p&gt;

Latest Quaternary sedimentation in the northern Gulf of Mexico Intraslope Basin Province: I. Sediment facies and depositional processes

Very high-resolution seismic facies, classified, mapped, and interpreted from 3.5 kHz echograms, reveal that turbidity-current, mass-transport, and bottom-current depositional processes have all contributed to the regional sediment distribution in the intraslope basin province of the northwest Gulf of Mexico. Piston cores from these deposits confirm the interpretations of the processes. Turbidity currents transport sands into the intraslope mini-basins via channels and canyons. A few turbidity-current pathways, such as Bryant Canyon, allow extensive volumes of terrigenous sediment to bypass through many mini-basins and be deposited beyond the Sigsbee Escarpment to form large submarine fans, such as Bryant Fan. Bryant Fan is a large mud-rich fan that extends hundreds of kilometers from the mouth of Bryant Canyon but has only one meandering channel on the modern seafloor that extends down the length of the fan. In contrast, the much smaller Rio Grande Submarine Fan is deposited on a plateau area of the continental slope. Prolonged 3.5 echo character and numerous small, unleveed channels suggest this is a sand-rich fan with a braided channel system. These two submarine fans appear to present unique architectural and growth patterns not previously described in the numerous fan descriptions of W.R. Normark or other workers. Thus, these two fans appear to represent two new types of fans, which may be related to the complex structures of the intraslope basin province. Mass-transport deposits (MTDs) are ubiquitous throughout the mini-basins. Extensive areas affected by MTDs also occur along the upper continental slope and at the base of the eastern portion of the Sigsbee Escarpment. Piston cores confirm that the majority of MTDs are debris flows, which are characterized by mud clasts of variable size, shape, and color. Most have a muddy matrix, but sandy debris flows also occur in a few mini-basins. Some cores show deformation, folds, and faults that indicate slump or slide deposits. The East Breaks Slide Complex is the largest MTD complex and extends downslope from the shelf edge for >100 km off central Texas. The western portion of the complex is slump and/or slide blocks and debris flows. In contrast, the proximal part of the eastern portion of the complex is characterized by a modern leveed turbidite channel system. However, extensive MTDs underlie the channel-levee deposits and occur at the seafloor on the distal part of the eastern portion of the complex. Three large regions of migrating sediment waves occur on the Sigsbee Abyssal Plain and eastern Bryant Fan and appear to have been formed by circulation of the Loop Current. Sediment waves also occur locally at the base of the Sigsbee Escarpment in conjunction with previously reported erosional furrows.

Dating of in situ longhouse (dubu daima) posts in the Kikori River delta: Refining chronologies of island village occupation in the lower Kikori River delta, Papua New Guinea

This paper examines the chronologies of three abandoned village sites in an attempt to refine the timing of occupation of low-lying mud islands of the lower Kikori River delta, Gulf Province, Papua New Guinea (PNG). Despite evidence for varying degrees of post-depositional disturbance at all three sites, meaningful chronological data can be obtained from the dating of in situ longhouse posts. These new data suggest that although initial delta island occupation probably began around 400–500 years ago as an initial response to new opportunities relating to the hiri trade, the very large villages ethnohistorically recorded for the delta islands may only have attained their impressive sizes somewhat later.

The probable role of cannibalism in spreading Trichinella papuae infection in a crocodile farm in Papua New Guinea

Between 2003 and 2007, 83 (50%) of 167 crocodiles (Crocodylus porosus) purchased as juveniles by a crocodile farm 3 or 4 years earlier from Kikori, Gulf Province, were found to be infected with Trichinella papuae. Between 2005 and 2007 infection was detected in a number of crocodiles at the farm obtained from six localities other than Kikori, as well as in a few animals born on the farm. Up to 2004, all juveniles at the farm, whether wild- or farm-born, were penned together; the practice was then stopped to prevent possible infection through cannibalism. The last infected animal from Kikori was seen in 2007, 4 years after the purchase of crocodiles from there ceased. The last non-Kikori infected crocodile was seen, also, in 2007. None of the 1972 crocodiles (comprising wild- and farm-born animals) tested from 2008 to 2013, using the digestion method, was infected with T. papuae. This indicates that infection of non-Kikori crocodiles was the result of cannibalism within the farm during the years up to 2004 when juvenile crocodiles were kept together, and that the farm is now free of the infection.

TB incidence and characteristics in the remote gulf province of Papua New Guinea: a prospective study

BackgroundThe incidence and characteristics of tuberculosis (TB) in remote areas of Papua New Guinea (PNG) are largely unknown. The purpose of our study was to determine the incidence of TB in the Gulf Province of PNG and describe disease characteristics, co-morbidities and drug resistance profiles that could impact on disease outcomes and transmission.MethodsBetween March 2012 and June 2012, we prospectively collected data on 274 patients presenting to Kikori Hospital with a presumptive diagnosis of TB, and on hospital inpatients receiving TB treatment during the study period. Sputum was collected for microscopy, GeneXpert analysis, culture and genotyping of isolates.ResultsWe estimate the incidence of TB in Kikori to be 1290 per 100,000 people (95% CI 1140 to 1460) in 2012. The proportion of TB patients co-infected with HIV was 1.9%. Three of 32 TB cases tested were rifampicin resistant. Typing of nine isolates demonstrated allelic diversity and most were related to Beijing strains.ConclusionsThe incidence of TB in Kikori is one of the highest in the world and it is not driven by HIV co-infection. The high incidence and the presence of rifampicin resistant warrant urgent attention to mitigate substantial morbidity in the region.

Patrones de distribución del género Zanthoxylum L. (Rutaceae) en México

The genus Zanthoxylum has a pantropical distribution pattern. Mexico is considered a center of diversification. Thus, in this work, we performed a track analysis using the program Trazos 2004® and 2 Parsimony Analyses of Endemicity (PAE): the first one was applied for the areas and the second for the vegetation types where the species live. We obtained 21 individual tracks and 2 generalized ones, for the Mexican Mountain Transition Zone and Neotropical region, respectively. We also obtained 3 nodes, 2 of them are located in the transition among Sierra Madre Oriental, Mexican Gulf and Oaxaca provinces and the other one is located in the province of the Mexican Gulf. The PAE groups the provinces of the Pacific Coast, Transmexican Volcanic Belt, Mexican Gulf, Oaxaca, Balsas Basin and the Sierra Madre del Sur in a set of clades succesively nested, supported by Zanthoxylum aguilarii, Z. culantrillo, Z. liebmannianum and Z. purpusii species, at different branches. The cladogram resulting by the PAE for vegetation types showed that the vegetation types of the temperate zones (cloud forest, Quercus and coniferous forest) are closely related in a single clade supported by 3 species Z. elegantissimum, Z. foliolosum and Z. melanorhachis.

Sasol Exits Iranian Venture

To help clear a path for a planned $20 billion in investments in Louisiana, Sasol, the South African energy and chemical firm, has agreed to sell its stake in its Iranian joint venture, Arya Sasol Polymer Co. The venture, to be sold to a South African affiliate of an Iranian investor, had become legally risky for Sasol as U.S. economic sanctions have mounted against Iran over its nuclear program. Sasol didn’t disclose the price of the transaction. It earlier valued the joint-venture stake at $223 million following a $191 million write-off of its worth. Sasol formed Arya Sasol in 2003 with National Petrochemical Co. of Iran to build a chemical complex in the Persian Gulf province of Bushehr. The partners completed an ethylene cracker in 2007. Polyethylene plants followed in 2009. Arya Sasol had been a solid performer for Sasol. In 2011, Sasol earned $45 million on $95 million in ...

Development of a Papua New Guinean onshore carbonate reservoir: A comparative borehole image (FMI) and petrographic evaluation

The depositional and diagenetic controls on carbonate platform evolution are notoriously heterogeneous and difficult to determine from standard subsurface wireline logging techniques. Here, a combined borehole image (FMI – Fullbore Formation MicroImager) and petrographic study allowed evaluation of depositional and diagenetic trends across an Australasian subsurface buildup that is a major recent gas discovery. The Elk and Antelope gas fields are hosted in Tertiary reefal, platformal and associated deep water carbonates in the present day foothills region of the Fold and Thrust Belt in the Gulf Province of Papua New Guinea.A full suite of FMI logs (>2800 m), and 292 thin sections (mainly from sidewall cores and cuttings) from both platform flank and shallow water deposits were evaluated during this study. Despite the obvious scale differences between the datasets there was some correlation between the independent petrography and FMI studies for: a) picking major facies boundaries, and b) interpretation of depositional environments, the latter particularly for slope and deep water deposits. However, thin section petrography proved critical in understanding primary depositional textures and secondary alteration features through the shallow-water carbonates where complex diagenetic overprinting had strongly impacted original fabric, and/or in regions affected by “gas smearing”. The petrographic study allowed more detailed examination of diagenesis and its impact on rock fabric (which links to the FMI textures). Component analysis and depositional textures identified in thin section are good indicators of original depositional environment. Full FMI coverage allowed textural definition on a dm/m scale, identification and characterisation of vertical changes, and likely large-scale variations in depositional environments and sequences. It was clear from combining the results of the two studies that diagenesis as well as depositional fabric had a strong impact on resultant FMI facies. The diagenetic overprinting would have been difficult to extract from the FMI data without the benefit of the petrographic work. This study shows the merits of selective petrographic analysis to calibrate the quality of facies interpretation from FMI images, and proved critical for enhancing and in places revising initial FMI interpretations.

An interesting new species of Nososticta Hagen from southern New Guinea (Odonata, Disparoneuridae)

Nososticta acuminata, a new disparoneurid damselfly from the Lakekamu Basin in Gulf Province of Papua New Guinea, is described. It is most similar to N. smilodon Theischinger &amp; Richards, but the male has uniquely pointed superior anal appendages.

Seasonal surface connectivity in the Gulf of California

A three-dimensional numerical model is used to study seasonal connectivity in the Gulf of California. From the Eulerian velocity fields of the model, particle trajectories were calculated for the 12 months of the year using an advection/diffusion scheme. Connectivity was quantified for twelve Gulf provinces with different dynamic/circulation characteristics being defined by the Eulerian velocity field: strong or weak coastal currents, eddies, and areas of mixing and exchange. Retention occurred for 9–12 months of the year in the Upper Gulf, Eddy and Sonora regions of the northern Gulf because of the Gulf-wide eddy circulation, which implies high potential for the auto-recruitment of larvae in this province. High retention was also found on the peninsula side of the southern Gulf in association with weaker residual currents, again implying potential for self-recruitment. In contrast, low retention was observed on the mainland side of the central and southern Gulf, from which particles are exported to many areas by the faster residual currents enhancing the potential for recruitment of distant coastal species. Empirical Orthogonal Function analyses revealed a strong annual and semiannual evolution in accordance with the strong seasonality of the Gulf dynamics.

Analysis of the Geographical Distribution ofParaphlebia zoeSelys in Hagen, 1861 (Odonata: Megapodagrionidae)

Paraphlebia zoe Selys in Hagen, 1861, an endemic Mexican species included in the IUCN Red List of threatened species, is recorded for the first time in Querétaro state. Based on recent collections in mountain cloud forests during the dry and rainy seasons, we added three new records for Hidalgo. There were compiled 16 historical records of the species, that permitted us to generate a range map for P. zoe showing that most records are from the southern region of the Sierra Madre Oriental with some records from the Mexican Gulf provinces. This distributional pattern also occurs in several species of Staphylinidae, Passalidae and Scarabaeidae.

Morphometric analyses of Batissa violacea shells from Emo (OAC), Gulf Province, Papua New Guinea

ABSTRACT Archaeological investigations of human predation pressures on shellfish usually rely on measurements of complete shell specimens. However, most archaeological shell assemblages consist predominantly of broken shells, limiting measurable sample sizes, and thus potentially biasing results in cases where shell fragmentation is biased towards particular size classes (due to shell size‐fragility correspondences). This paper presents a recent application of morphometric analyses on the Batissa violacea assemblage from Emo, an early ceramic site from the Gulf Province, Papua New Guinea. Our method enabled most shell valves, fragmented or not, to be accurately and comparably measured for size. The results reveal a close match between the commencement of occupation and maximum shell sizes in a sequence of occupational phases, each separated by many decades to hundreds of years of site abandonment. While each occupational phase begins with peak mean shell sizes, the later peaks never again attain the mean shell size of the initial phase. As each phase progresses, shell sizes diminish until abandonment, and then the same pattern starts again with the next phase. Identical trends were obtained from two separate excavation squares. We interpret these results to indicate that while people may have abandoned the site of Emo between the occupational phases, they did not abandon the region, continuing to exploit local shellfish beds, albeit less frequently than during the site's occupation. These results highlight the ability of local (site‐specific) archaeological shell data to shed light on regional demographic and occupational trends.

New species (130) of the hyperdiverse aquatic beetle genus Hydraena Kugelann from Papua New Guinea, and a preliminary analysis of areas of endemism (Coleoptera: Hydraenidae)

New species (130) of the hyperdiverse aquatic beetle genus Hydraena Kugelann from Papua New Guinea, and a preliminary analysis of areas of endemism (Coleoptera: Hydraenidae)

Magnetometer surveys in archaeological research in Papua New Guinea: Keveoki 1, Gulf Province

ABSTRACT A magnetometer survey was conducted on the abandoned village site of Keveoki 1, near the Vailala River, Gulf Province, PNG. The survey, using a single sensor proton precession magnetometer, was successful in locating and defining the boundaries of areas confirmed by excavation to contain dense assemblages of pottery. The combination of geophysical and excavation results allowed a broader understanding of the spatial distribution of human occupation at Keveoki 1 than would have been possible based on excavation or visual field walking alone. We suggest this technique should be applied more regularly.

Historicising The Present: Late Holocene Emergence of a Rainforest Hunting Camp, Gulf Province, Papua New Guinea

Historicising the emergence of ethnographic activities provides insights into the reliability of ethnographic analogies to aid archaeological understandings of past human societies, as well as allowing us to explore the historical emergence of ethnographically contextualised cultural traits. Epe Amoho is the largest hunting camp rockshelter used by the Himaiyu clan (Rumu people) of the Kikori River region, southern Papua New Guinea. Contemporary ethnographic information indicates dry season site use with subsistence practices directed towards riverine fishing and shellfishing, mammal hunting and gardening in the surrounding rainforest. But how long has the site been used and when in the past did activities start to resemble those known ethnographically? Archaeological excavations revealed three pulses of activity: Recent Phase (0-500 cal BP), Middle Phase (900-1200 cal BP) and Early Phase (2500-2850 cal BP). Pollen data reveal increasing rainforest disturbance by people through time. While the best match between ethnographic and archaeological practices occurs during the Recent Phase, selected aspects of Rumu subsistence extend back to the Early Phase. As the temporal depth of ethnographically-known practices differs between archaeological sites, a complex picture emerges where Rumu cultural practices unfolded at differing points in time and space over a period of at least 3000 years.

The Emo Site (OAC), Gulf Province, Papua New Guinea: Resolving Long-Standing Questions of Antiquity and Implications for the History of the Ancestral Hiri Maritime Trade

Since the 1970s the site of Emo (aka ‘Samoa’, ‘OAC’) in the Gulf Province of Papua New Guinea has been cited as one of the earliest-known ceramic sites from the southern Papuan lowlands. This site has long been seen as holding c.2000 year old evidence of post-Lapita long-distance maritime trade from (Austronesian-speaking) Motu homelands in the Central Province, where pottery was manufactured, to the (non-Austronesian) Gulf Province some 400km to the west where pottery was received and for which large quantities of sago were exchanged (the ancestral hiri trade). However, until now the only three radiocarbon dates available for Emo were out of chronostratigraphic sequence, and few details on the site had been published. This paper presents the results of new excavations and the first detailed series of AMS radiocarbon determinations from Emo, thereby resolving long-standing uncertainties about the age of the site and its implications for the antiquity of the long-distance Motuan hiri maritime trade.