Onshore Waters Research Articles

Characterization and distribution of plastic particles along Alexandria beaches, Mediterranean Coast of Egypt, using microscopy and thermal analysis techniques

Microplastics (MPs) contamination has become a global concern with potential impacts on the marine environment. Alexandria is the second-largest city in Egypt and a significant contributor of plastic litter inputs into the Eastern Mediterranean Sea. The current study provides an in-depth analysis of the plastic particles accumulated along Alexandria beaches. Types, composition, and potential sources of MPs were investigated using microscopy and thermal analysis. A mean value of 389.1 ± 285.9 items kg−1 dry weight was detected in the shore sediments similar to other records from the Eastern Mediterranean region. An average of 457.4 ± 281.8 items m−3 was recorded in the surface water, which was the highest recorded MPs density in onshore waters of the Mediterranean region. Thermogravimetric analysis (TGA) showed that plastics made up 0.5% - 72% of the materials extracted from the sediment samples, and 0.58% - 20.6% from the water samples. Differential scanning calorimetry (DSC) identified ten semi-crystalline polymers. Low-density polyethylene (LDPE) and polyethylene vinyl acetate (PEVA) were the common polymers. The single-use plastic bags and detergents were the land-based sources of marine plastic litter. The sea-based sources included antifouling paints, maintenance of ships, and abandoned fishing gears. Proper management plans of domestic waste input, polluter-pay strategy, and education programs aiming at the Fishermen and how plastic pollution would impact their livelihood are urgently needed.

Carbon Dioxide Enhanced Oil Recovery and Residual Oil Zone Studies at the U.S. Geological Survey

The U.S. Geological Survey (USGS) is preparing a national resource assessment of the potential hydrocarbons recoverable after injection of carbon dioxide (CO2) into conventional oil reservoirs in the United States. The implementation of CO2-enhanced oil recovery (CO2-EOR) techniques can increase hydrocarbon production, and lead to incidental retention of CO2 in reservoir pore space allowing long-term storage of anthropogenic CO2. A Comprehensive Resource Database (CRD) containing proprietary data on location, geologic, petrophysical, and reservoir parameters, plus production and well counts for major oil and gas reservoirs in onshore areas and State waters of the conterminous United States and Alaska, was developed to support the USGS assessment. Residual oil zones (ROZs) also can provide potential pore space for long-term storage of anthropogenic CO2. However, ROZs are not included in the upcoming USGS national CO2-EOR assessment because assessment methods for ROZs still are being developed. Additional ROZ CO2-EOR and CO2 retention data and reservoir simulations are needed to calibrate national ROZ assessment estimates.

Evaluation of SARAL/AltiKa performance using GNSS/IMU equipped buoy in Sajafi, Imam Hassan and Kangan Ports

Performance of SARAL/AltiKa mission has been evaluated within 2016 altimeter calibration/validation framework in Persian Gulf through three campaigns conducted in the offshore waters of Sajafi, Imam Hassan and Kangan Ports, while the altimeter overflew the passes470, 111 and 25 on 13Feb, 7March and 17June2016, respectively. As the preparation, a lightweight buoy was equipped with a GNSS receiver/choke-ring antenna and a MEMS-based IMU to measure independent datasets in the field operations. To obtain accurate sea surface height (SSH) time series, the offset of the onboard antenna from the equilibrium sea level was predetermined through surveying operations as the buoy was deploying in the onshore waters of Kangan Port. Accordingly, the double-difference carrier phase observations have been processed via the Bernese GPS Software v.5.0 so as to provide the GNSS-derived time series at the comparison points of the calibration campaigns, once the disturbing effects due to the platform tilt and heave have been eliminated. Owing to comparing of the SSH time series and the associating altimetry 1 Hz GDR-T datasets, the calibration/validation of the SARAL/AltiKa has been performed in the both cases of radiometer and ECMWF wet troposphere corrections so as to identify potential land contamination. An agreement of the present findings in comparison with those attained in other international calibrations sites confirms the promising feasibility of Persian Gulf as a new dedicated site for calibration/validation of ongoing and future altimetry missions.

Australian onshore petroleum acreage release 2016

This paper compiles material from state and territory jurisdictions describing the location and resource potential of Australian onshore and coastal waters acreage to be made available for petroleum exploration in 2016. The Australian state and territory governments continue to support investment in the petroleum industry through the annual provision of land for exploration, which is promoted nationally and internationally. Technical assessments are provided with the release, which detail the potential for conventional and/or unconventional resources. The level of assessment will depend on exploration maturity, but may include a description of the geological setting, review of exploration history, summary of key results, and subsurface maps/sections. In addition to this, any updates on recent upstream developments and government initiatives, as well as present and future policy directions that relate to onshore petroleum exploration, may be described, particularly for jurisdictions that are not making land available this year. With global demand for gas—led by Asia—expected to grow at 2.6% annually between 2015 and 2025, investing in Australia’s petroleum and gas industry presents a significant opportunity to supply into this growing market.

Diversity of migratory environmental history of the mullets Mugil cephalus and M. curema in Mexican coastal waters as indicated by otolith Sr:Ca ratios

To understand their migratory environmental history and habitat use in Mexican waters, 31 striped mullet Mugil cephalus and 40 white mullet M. curema (family Mugilidae) were collected from three habitats (Tamiahua Lagoon, and Cazones and Tecolutla estuaries, Veracruz) in the western Gulf of Mexico. Sr:Ca ratios in otoliths of mullets were measured from the primordium to the otolith edge with an electron probe microanalyzer. Mullets were aged by counting the otolith annuli. The patterns in mullet otolith Sr:Ca ratio differed among habitats and between species, indicating that habitat use and migratory behavior differed between species. Variability in otolith Sr:Ca ratios was consistent with that of the environment inhabited by the mullets. They showed a more diverse euryhaline preference than the simple catadromous behavior expected. The Sr:Ca ratios in the core region of the otolith indicated that mullets can spawn in both offshore waters and nearshore brackish waters, or that spawning may occur in offshore waters and that onshore currents/winds carry the fertilized eggs into onshore waters where salinities are lower. Peak Sr:Ca ratios corresponded to otolith annulus deposition, which validated the difference in timing of seaward spawning migration between striped mullet (winter) and white mullet (spring).

Distribution and abundance of thaliaceans in the northwest continental shelf of South China Sea, with response to environmental factors driven by monsoon

The distribution and abundance of thaliaceans were studied in relation to physical and biological variables during summer and winter in the northwest continental shelf of South China Sea. Based on the topography and water mass of the surveyed region, it was divided into three subregions: region I (onshore waters of the east Leizhou Peninsula), region II (onshore waters of the east and southeast Hainan Island) and region III (offshore waters from Leizhou Peninsula to Hainan Island). During summer due to a strong southwest monsoon, a cold eddy and coastal upwelling dominated in regions I and II, respectively, whereas the onshore and offshore waters were vertically mixed during winter due to a strong northeast monsoon. A total of 18 thaliacean species (including 3 subspecies) were collected. The mean species richness was higher in summer compared to winter, with the occurrence of higher values during summer and winter at region II and region III, respectively. The average thaliacean abundance is also higher in summer than in winter, with higher values at region I in summer and no significant difference among three subregions in winter. Doliolum denticulatum and Thalia democratica were the dominant species during summer and winter. The results suggested that the seasonal and spatial distribution of thaliacean richness was considered to be the result of physical factors such as temperature and ocean current in summer and winter. Spatial distribution of thaliacean abundance was affected by chlorophyll a concentration increased by the occurrence of coastal upwelling and cold eddy in summer. Southwest and northeast monsoons are shown to play an important role in shaping the distribution of species richness and abundance of thaliaceans in the northwest continental shelf of South China Sea.

Australian States and Northern Territory acreage update at APPEA 2010

Peter Green is the Geoscience Manager: Energy Geoscience in the Geological Survey Queensland and has extensive experience in basin studies, geoscience and the development of petroleum regulation in Queensland. This paper provides a summary of the land releases for petroleum exploration for onshore areas and coastal waters of Australia for 2010. The summaries include upstream petroleum acreage opportunities for the states and the Northern Territory, and geothermal energy exploration opportunities. The rise in interest in export liquefied natural gas projects has ensured petroleum exploration and production has remained strong. Interest in acquiring petroleum acreage to explore for both conventional and non-conventional plays remains high. Australian state and the Northern Territory governments continue to provide access to land and promotional opportunities for companies to undertake exploration and development of our petroleum resources. Acreage on offer provides a mix of exploration opportunities from conventional oil and gas through to the unconventional plays such as shale gas and tight gas. This change in acreage on offer reflects the changing nature of the onshore petroleum industry in Australia.

Assessment of undiscovered conventional oil and gas resources, onshore Claiborne Group, United States part of the northern Gulf of Mexico Basin

The middle Eocene Claiborne Group was assessed for undiscovered conventional hydrocarbon resources using established U.S. Geological Survey assessment methodology. This work was conducted as part of a 2007 assessment of Paleogene–Neogene strata of the northern Gulf of Mexico Basin, including the United States onshore and state waters (Dubiel et al., 2007). The assessed area is within the Upper Jurassic–Cretaceous–Tertiary composite total petroleum system, which was defined for the assessment. Source rocks for Claiborne oil accumulations are interpreted to be organic-rich, downdip, shaley facies of the Wilcox Group and the Sparta Sand of the Claiborne Group; gas accumulations may have originated from multiple sources, including the Jurassic Smackover Formation and the Haynesville and Bossier shales, the Cretaceous Eagle Ford and Pearsall (?) formations, and the Paleogene Wilcox Group and Sparta Sand. Hydrocarbon generation in the basin started prior to deposition of Claiborne sediments and is currently ongoing. Primary reservoir sandstones in the Claiborne Group include, from oldest to youngest, the Queen City Sand, Cook Mountain Formation, Sparta Sand, Yegua Formation, and the laterally equivalent Cockfield Formation. A geologic model, supported by spatial analysis of petroleum geology data, including discovered reservoir depths, thicknesses, temperatures, porosities, permeabilities, and pressures, was used to divide the Claiborne Group into seven assessment units (AUs) with three distinctive structural and depositional settings. The three structural and depositional settings are (1) stable shelf, (2) expanded fault zone, and (3) slope and basin floor; the seven AUs are (1) lower Claiborne stable-shelf gas and oil, (2) lower Claiborne expanded fault-zone gas, (3) lower Claiborne slope and basin-floor gas, (4) lower Claiborne Cane River, (5) upper Claiborne stable-shelf gas and oil, (6) upper Claiborne expanded fault-zone gas, and (7) upper Claiborne slope and basin-floor gas. Based on Monte Carlo simulation of justified input parameters, the total estimated mean undiscovered conventional hydrocarbon resources in the seven AUs combined are 52 million bbl of oil, 19.145 tcf of natural gas, and 1.205 billion bbl of natural gas liquids. This article describes the conceptual geologic model used to define the seven Claiborne AUs, the characteristics of each AU, and the justification behind the input parameters used to estimate undiscovered resources for each AU. The great bulk of undiscovered hydrocarbon resources are predicted to be nonassociated gas and natural gas liquids contained in deep (mostly 12,000-ft [3658 m], present-day drilling depths), overpressured, structurally complex outer shelf or slope and basin-floor Claiborne reservoirs. The continuing development of these downdip objectives is expected to be the primary focus of exploration activity for the onshore middle Eocene Gulf Coast in the coming decades.

Australian States and Northern Territory acreage update at APPEA 2009

Richard Sellers is the executive director of minerals and energy in the Northern Territory and has extensive experience with the management of natural resources and working specifically with business, regional and Indigenous groups on development programs. He has previously held roles as Executive Director—Fisheries and Director—Legal and Policy in the former Northern Territory Department of Primary Industry and Fisheries. This paper covers the annual presentation of exploration activity in onshore and coastal waters in Australia’s states and the Northern Territory. Included is a summary of upstream petroleum acreage opportunities for 2009 in the states and Northern Territory as well as geothermal energy exploration opportunities. While there have been increasing levels of exploration in recent years, there are large areas that remain under explored and the opportunity for future discoveries remains. State and the Northern Territory Governments have continued to undertake initiatives to attract and facilitate accelerated exploration and promote nationally and internationally these opportunities in frontier and production areas.

Australian states and Northern Territory acreage update at APPEA 2008

This is the annual presentation of what’s happening in onshore and coastal waters exploration in Australia’s states and the Northern Territory. The main focus of these jurisdictions’ annual report at the APPEA conference is upstream petroleum acreage opportunities. Exploration for geothermal energy resources will also be covered. There are many and diverse exploration opportunities in onshore frontier and producing Australian basins available for explorers in 2008, including geothermal energy exploration opportunities. The number of onshore Australian acreage applications has been steadily increasing in recent years and this has resulted in higher levels of drilling and seismic acquisition, but large areas remain untouched by modern exploration. Australian state governments continue initiatives to encourage exploration to realise their natural resource endowments including: pre-competitive basin studies; speedy and cost-effective provision of digital exploration data; provision of effective land access regimes; transparent regulatory regimes; internationally competitive royalty regimes; and, promotion of acreage releases nationally and internationally.

Biogeochemical and physical factors influencing seawater ƒCO2 and air‐sea CO2 exchange on the Bermuda coral reef

It is uncertain whether coral reef ecosystems are oceanic sources or sinks of carbon dioxide (CO2). Understanding the complex interactions between biogeochemical and physical processes within reef ecosystems is important for determining the contribution of coral reefs to the global carbon cycle and the air‐sea flux of CO2 . The influence of biogeochemical and physical processes on CO2 cycling was examined for 1 month at Hog Reef Flat, part of the rim reef of Bermuda. The fugacity of seawater CO2 (ƒCO2) was measured hourly by use of a Carbon Interface Ocean Atmosphere buoy, providing the longest time series of seawater CO2 data on a coral reef ecosystem. Seawater ƒCO2 ranged from ~340 to 470 µatm, with a diurnal variability ranging from ~20–60 µatm. Air‐sea CO2 was directed from ocean to atmosphere with a mean flux of 3.3 ± 4.6 mmoles CO2 m−2 d−1. The reef data are compared with a seawater CO2 time series collected at the U.S. Joint Global Ocean Flux Study Bermuda Atlantic Time‐series Study (BATS) site (31°50'N, 64°10'W) in the Sargasso Sea surrounding Bermuda. Sargasso Sea waters are the original source for Bermuda platform water, providing a context for understanding the biogeochemical modification of reef water at Hog Reef Flat. Seawater fCO2 at Hog Reef Flat was elevated relative to the Sargasso Sea by ~0 to ~120 µatm, primarily as a result of calcium carbonate production. However, the ability of the reef to act either as a source or sink of CO2 to/from the atmosphere largely depended on the air‐sea CO2 disequilibrium of offshore Sargasso Sea waters impinging on the reef site. This study also revealed that an assessment of the fate of CO2 on coral reefs is dependent on understanding the reef's physical regime and forcing. The dynamics of wind, tide, platform circulation, and fluxes of offshore or onshore waters are necessary context for all coral reef sites.

Small Fields in the National Oil and Gas Assessment

In the 1989 National Oil and Gas Assessment prepared by the U.S. Geological Survey (USGS) and the Minerals Management Service, undiscovered oil and gas resources in small fields were assessed separately from resources in fields containing more than 1 million bbl of oil equivalent. This paper concerns the USGS Part of the study: onshore and state waters in the conterminous United States. After the resources in small fields were assessed by geologists, statistical techniques were used to allocate these resources to field-size distributions at the province level. The total numbers of small fields remaining to be discovered is estimated at about 77,800. They account for about 10.6 billion bbl of oil equivalent or 20% of the undiscovered resources in the conterminous United st tes. When an economic analysis was applied to the small fields, none of the offshore small fields were estimated to be commercially developable. For the onshore study area, about 52% of the small oil fields and 46% of the small gas fields are commercially developable. Overall, because more hydrocarbons are contained in the larger size classes of the small fields, about 70% of the undiscovered resources in small fields is expected to be commercially developable.

Review on the effects of pollution on marine fish life and fisheries in the North Sea

Information on possible effects of pollution on fish life is reviewed with special emphasis to the North Sea. Concentrations of heavy metals are high in onshore waters, sediments and organisms. Offshore regions are considered to be not endangered. In estuaries concentrations of certain heavy metals are often surpassing thresholds, which have been experimentally demonstrated to produce sublethal effects on marine organisms. Also mussel culture areas had to be closed due to excess of cadmium contamination. Mercury in fillets of cod in the southern North Sea sometimes reaches 0.3 ppm representing 1/3 of the legal limit. Reductions of inputs are necessary due to the bioaccumulative and toxic potential of heavy metals. Organochlorine contamination of water, sediments and organisms is higher in the southern than in the northern North Sea. In offshore areas clearly elevated levels of PCB's, which are the dominating organochlorine compound in marine organisms, have been analyzed. At present only a minor fraction of total organochlorine residues accumulated in marine biota is analyzed. Margins between experimentally derived lethal levels and those occurring in marine biota are narrow suggesting that sublethal effects might occur. One of the special concerns in the context of organochlorine contamination has to be seen in the potential of these substances affecting the reproductive capacity of marine organisms. Reduction measures are urgently necessary and should include substances with bioaccumulative and toxicological potential, which are not presently included in Marine Monitoring Programmes. Impact of oil pollution is considered to be a regional problem, although especially in estuaries concentrations in the water column might be high. Input through oil platforms has led to local reductions in benthic communities. Measures have to be taken, to further reduce these inputs also in view to avoid contamination of fish in the vicinity of oil fields. Oxygen depletion in German and Danish coastal waters has been shown to be a severe degradation in coastal water quality resulting in significant impact on fish populations. Indications for large-scale avoidance reactions of low DO-areas and mortalities of fish and benthos organisms have been demonstrated. It is suspected that the low DO-situations are related to increased nutrients input and high phytoplankton production. Improvement of the situation can only be expected, if input of nutrients is reduced. Reasons for the occurrence of toxic plankton blooms are not understood. An intensified research is necessary, to avoid damage to fisheries and mariculture. Although activity of radionucleids in North Sea waters is increased due to input of radioactive material from La Hague and Sellafield reprocessing units, the present levels of activity are not considered to be a threat for marine life. The same holds for thermal pollution, which is, depending on the recipient area, expected to have only local effects. Sewage sludge dumping and discharge of untreated sewage introduce significant amounts of accompanying heavy metals, which can be expected to have a negative influence on the total metal budget of recipient waters. Nutrient input through sewage will exhibit only local effects. Dumping of wastes from titanium dioxide industry are suspected to be causally linked to the occurrence of increased prevalences of certain diseases of dab in the German Bight. Present management strategies should take account of the fact that through dumping of waste from titanium dioxide production significant quantities of heavy metal are introduced into the southern North Sea. Also the incineration of chemical wastes at sea should be reduced due to uncertainties concerning quantities and toxicity of incineration products and their potential impact on marine life. It is concluded that clear evidence exists for pollution impact in estuarine regions. Most of the major estuaries at the North Sea coast show benthos reductions, which can be related to water quality and it has to be assumed that areas of a sublethal effect are located in the vicinity of those areas of well demonstrated effects. They are of unknown size and attempts have to be undertaken to quantify areas of sublethal impact. The occurrence of fish diseases is interpreted as an expression of degraded water quality. Some of the diseases detected can produce mortality, thereby having an as yet unquantified impact on fish populations. The presence of fish diseases also reduces the marketability of catches. It cannot be excluded that changes in species composition of fish populations in German Wadden Sea areas are related to pollution. Concentrations of organochlorine substances in fishes of the southern North Sea give rise to the concern that their reproductive capability might be impaired. Future work has to be directed to this problem. Impact of pollution on populations of marine organisms has so far not been demonstrated.

Reaction of shallow onshore waters to ground shock

abstract Pressures and accelerations were measured in and near numerous ponds and lakes in Amchitka during the nuclear shot CANNIKIN, using peak measuring and full time-history recording instruments. The resulting pressures and accelerations were similar in wave shape: each showed an initial pulse, a period of free fall during spall, and an impact shock. It is found that when reverberation times in the water are short compared to rise times and other characteristic times of the ground shock, the water responds as a whole, and the pressure in it is proportional to the acceleration. When reverberation times are longer than rise times, pressure overshoots and oscillates about the simple proportionality.

Ecological Notes on a Lake-Dwelling Population of Longnose Dace (Rhinichthys cataractae)

Longnose dace were found from early July to September in onshore waters on the east side of Hecla island in the southern basin of Lake Winnipeg. They were most abundant on rocky substrates, where they spawned in early July. It is suggested that at other times of the year these fish occupy deep channels between islands where current is present. While in onshore waters fish less than 5 g adjusted their buoyancy by altering swimbladder volume in response to presence or absence of wave action. Swimbladder volume was similar to that of river-dwelling populations of this species.

Segregation Between Adult Cutthroat Trout (Salmo clarki) and Dolly Varden (Salvelinus malma) in Small Coastal British Columbia Lakes

Comparison of spatial distributions and food of allopatric populations of cutthroat trout (Salmo clarki) and Dolly Varden (Salvelinus malma) in two lakes and of sympatric populations in a third lake suggested interactive segregation. Allopatric cutthroat changed their depth distribution throughout the spring and summer but no diel migration was noted. Changes in food habits closely corresponded to seasonal changes in vertical distribution. A wide range of food organisms was eaten from surface, midwater, and benthic sources. Allopatric Dolly Varden underwent diel changes in spatial distribution, with many being caught in onshore waters near the surface at night. They were absent from such areas in the day, apparently occupying offshore waters at greater depths. Their diet throughout summer consisted largely of surface insects and zooplankton, with lesser amounts of bottom fauna.Sympatric cutthroat trout and Dolly Varden were spatially segregated throughout the summer. Cutthroat trout occurred and fed mostly near the surface in littoral areas. In contrast, Dolly Varden were offshore and benthic in distribution and fed primarily on bottom organisms. By comparing distribution and food habits in allopatric and sympatric populations, it was suggested that competition for food may contribute to their segregation in sympatry. Although segregation of these species when cohabiting may involve interactive processes, the possibility of selective differences being of importance cannot be dismissed.