Extraterrestrial Metallic Iron in the Lacustrine, Epicontinental and Oceanic Sediments

The article represents an overview and generalization of the microprobe and thermomagnetic data on the distribution, content and composition of metallic iron in Pleistocene lacustrine sediments of the Darhad Basin, northern Mongolia, in the Upper Miocene sediments of Lake Baikal.

Epicontinental sediments of Miocene-Late Jurassic, and Early Cambrian ages in different regions of North Eurasia and in Miocene-Late Jurassic oceanic sediments of North- Western Atlantic.

Iron particles percentage varies from ~10-5 to 0.05%, their distribution is bimodal with the distinct zero mode, and the accumulation of iron particles is inversely linked with the rate of sedimentation. Pyrite and pyrrhotite are widespread in the studied sediments, and the distribution of metallic iron does not depend on the presence of pyrite.

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Soil Erosion Assessment of the Poyang Lake Basin, China: Using USLE, GIS and Remote Sensing

Soil erosion is one of the most critical eco-environmental issues in the Poyang Lake basin, China. The purpose of this study is to discover the spatial pattern of soil erosion, and predict soil loss and sediment yield, and evaluate soil loss impacts on main reservoirs by using Universal Soil Loss Equation (USLE), GIS and Remote Sensing (RS).

Firstly, five erosion factors including rainfall erosivity (R), soil erodibility (K), topographic factor (LS), cover and management factor(C), and conservation supporting practice factor (P) were calculated and analyzed, respectively. Secondly, annual soil erosion and its spatial distribution were evaluated, and sediment yield was subsequently predicted.

Next, soil erosion was classified into five erosion categories according to Industry Standard of Water Resources of China. Then, the relationship among soil erosion, landform and land use and land cover (LULC) were analyzed. Finally, the influence of soil erosion on main reservoirs in the basin were assessed.

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Oromo Indigenous Knowledge and Practices in Natural Resources Management: Land, Forest, and Water in Focus

This study deals with the Oromo indigenous knowledge and its implication in the practices of natural resources management, with the focus on the natural resources that have been thought as fundamental and integrals of their entire lives: land, forest, and water resources.

The study was conducted among Nole, Maccaa Oromo of West Wallagga. The study of the predominant human-environment relationship, and the indigenous ecological knowledge and practices of indigenous peoples in natural resources and biodiversity conservation have enormous role in understanding the ever-growing environmental problems, and consequent social problems.

Hence, in an effort to understand the cause and magnitude of environmental problems, and to establish prospective measures that would help in solving these social and environmental acute, understanding the community’s worldview and integrated indigenous knowledge that they have been maintained in esteeming and managing the natural resources for healthy coexistence is important.

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Comparison of the Characteristics of Low Velocity Layer (LVL) in the Mangrove Swamp and in the Upper Flood Plain Environments in the Niger Delta, using Seismic Refraction Methods

Sixteen (16) surface-laid-geophones and fourteen (14) downhole-laid-hydrophones experiments were conducted in Upper Flood Plain and in Mangrove Swamp areas respectively in parts of the Niger Delta.

The aim is to compare low-velocity-layer (LVL) characteristics in the two environments. The velocity and depth of the weathered layer and those of the consolidated layers were calculated using depth-time plots.

The interpreted data showed a substantial variation of the weathered layer thickness and elevation in the two study areas. In the Upper Flood Plain, LVL thickness varies between 2.8 m and 40 m with an average of 21.46 m.

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Remediation of Escravous Crude Oil Contaminated Soil Using Activated Carbon from Coconut Shell

Environmental pollution is one of the major hazards facing humanity in the quest for energy today. In Nigeria, the activities of oil exploration and exploitation have repeatedly exposed the environment to the effect of hydrocarbon spill.

This research work was carried out to investigate the potential of activated carbon produced from coconut shell to treat Escravous crude oil contaminated soil, by varying pollutant dosage, adsorbent dosage and time.

The present study has clearly demonstrated that activated carbon from coconut shell (ACCS) can be used to significantly enhance the rate of degradation of petroleum hydrocarbon in the soil when homogenized with water in a ratio of 20 w/w and studied under an atmospheric temperature.

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Environmental Health Risk Estimation of Heavy Metals Accumulated in Soil and Cultivated Plants Irrigated with Industrial Effluents

Indiscriminate release of industrial wastewater/mining wastes into the water bodies and reuse of this polluted wastewater for agriculture purpose is a topic of debate for sustainable development.

These wastewater containing heavy metals (density of >5 g cm-3) in toxic levels is of great health concern for human and animal through food web. Durgapur Industrial Belt (DIB) of India is discharging effluents into the Tamala Drain (TD) leading to metal pollution of water-soil system and also affects biota of the area.

Locals farmers are using for cultivating food crops, pulses and vegetables because they are ignorant about the hidden toxicity of the factory discharged and their subsequent negative impacts such as loss of soil fertility/crop yield, bioconcentration of metals in edible parts or forage plants.

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Assessment of the Impacts of Sea Level Rise on Mangrove Dynamics in the Indian Part of Sundarbans Using Geospatial Techniques

The intertidal mangrove ecosystem of Indian Sundarban is now as a critical ecosystem due to climate changeinduced sea level rise. The present study analyses the responses, migration, destruction and vulnerability of the four deltaic mangrove ecosystem, such as Jambudwip, Bulcherry, Dalhousie and Bangaduni Islands along the ocean sides. The changes in this deltaic ecosystem studied by using GIS and remote sensing with collecting data about sea level of nearest tidal gauge station Haldia (2.59 ± 1.0 mm/year) and Diamond Harbor (4.67 ± 0.68 mm/year). 

The study finds that if the sea level rises about mangrove surface, the mangrove retreats landward and also decline the land areas, increases soil erosion that affected in the southern and south-western part where these vulnerable mangrove islands are located. 

The Factors for the Extinction of Jaguars and Cougars in El Salvador

Human population increase, intensified land use and attitudes to wildlife, as well as habitat losses, hunting and pollution have devastated the global biodiversity, even in ecological “hotspots” such as Central America.

Of all wild mammal species, half have declining populations and one quarter is threatened with extinction. Large carnivores are particularly affected, due to low population densities, human fear and attitudes, physical conflict, their mobility and requirement of large tracts of land and wide ranging prey species, and consequent difficulties of conservation.

Consequently, the creation of reserves may be fruitless, due to land use conflicts with other pressing requirements, such as urbanization and agriculture, and the difficulty of restricting large carnivores to land inside the reserves.

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Infill Development: an Approach to the Optimal and Intelligent Development of Cities - Case Study: Zone 8 of Tabriz

Today, about 50% of the world population or three and a half billion live in cities but it is expected that by 2050, the urban population of the world increases by 84%; namely, 3.6 billion people.

Although population growth is the primary cause of the spread of cities, the same irrational distribution or horizontal expansion and new construction around the city caused socio-economic damages and destruction of environmental resources in the cities and surroundings.

Due to a substantial effect of the form of a city on its stability, it is necessary to know study and understand its dimensions and guide it to achieve sustainable development. After 1970s and the World War II, severe reactions to uncontrolled growth of cities began.

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Simulated Impact of Intensification of Irrigation on Indian Monsoon Rainfall and Surface Fluxes

Agriculture, human health, major weather and climate phenomenon are impacted by climate change. Indian subcontinent is home to one-sixth of world population, where the Indian summer monsoon rainfall (ISMR) is important for irrigation activities.

Within India, there is also evidence that intensive irrigation has led to changes in monsoon rainfall patterns with Lohar and Pal reporting that doubling of the area covered by summer paddy crops in West Bengal is a possible cause for mean monthly rainfall from 1983-1992, less than half that observed from 1973-1982.

The two-dimensional numerical simulations indicate that wetter soils along the coast reduce the temperature gradient between the land and the sea, hence reducing the intensity of sea breeze circulations and, therefore, lead to diminished pre-monsoon rainfall.

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Renovated Breeding Habitat use in Wild & Captive-bred Populations of an Endangered Desert Pupfish

Habitat loss is a persistent threat for endangered species, with both natural and human factors contributing to the devastating fragmentation of natural environments. In extreme cases, this fragmentation can result in species having little to no natural habitat remaining in which to repopulate.

Attempts to combat this growing phenomenon have emerged in the form of rebuilding or expanding natural habitats in order to facilitate population re-growth. However, the success of such projects has been limited, and as a result, habitat restoration alone is considered an unreliable method of mitigating species loss.

This is largely due to restoration attempts facing a myriad of constraints that can impact both short and longterm progress, and a large proportion of restoration projects being deemed insufficient in terms of increasing population size.

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THIS BACTERIA CAN REDUCE SODIUM LEVELS IN WASTE WATER

Water is the most vital resource for all kinds of life, but it is being adversely affected both quantitatively and qualitatively. Today, most of the rivers receive millions of litre of sewage and industrial effluents containing varying characteristics from simple nutrients to highly toxic substances.

Because of increasing population and industrial developments, a huge amount of wastewater is discharged to the environment above the level that the nature can eliminate. One of the most important industrial activities in India with its magnitude of economy is the textile industry.

Textile industry discharges a complex huge volume of waste water containing various chemicals used in dyeing, printing and finishing processes. The effluent generated in different steps or processes is well beyond the standard and thus it is highly polluted and dangerous

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A Negative Binomial with a Non-Homogenous Gamma Distributed Mean for Robustifying Pseudo R2 Regression Values of Immature Vector and Nuisance Mosquito

Automobile tires discarded in undeveloped land plots near anthropogenic and animal habitations are a health hazard because they can support an immature population of vector mosquitoes.

These mosquitoes may transmit several zoonotic arboviral diseases. Hillsborough County, Florida has recorded anthropogenic cases of locally-acquired West Nile virus, Eastern equine encephalitis, and La Crosse encephalitis in the past few years.

Unfortunately, there are no means to locate waste tires dumped near georeferenced human dwellings besides ground-based searches. Thus, location techniques for waste tires that conserve limited funds and human resources are needed for arboviral disease prevention via tire removal in Hillsborough County.

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Assessment of Ambient Air Quality with Special Reference to NO2 in the Waste Dump Site at Osisoma Ngwa LGA, Nigeria

Air pollution is woven throughout the fabric of our modern life. Pollution problems began with the growth of cities and population and their related water, industrial and disposal needs. With the increase of urbanization man began to intrude on the beautiful, balanced mechanism of the atmosphere.

Nitrogen oxides include chiefly NO, NO2 and HNO3 mostly released by automobiles, power-plants and chemical from industries. The industries manufacturing HNO3 and other chemicals and the automobile exhausts are the chief source of the Nitric Oxide (NO) gas to the environment.

At high temperature, combustion of gasoline produces this gas. A number of chemical reactions serially convert a large amount of NO to more toxic NO2 in the atmosphere. NO is responsible for the several photochemical reactions in the atmosphere, particularly in the formation of several secondary pollutants like PAN, O3, Carbonyl compounds, etc.,

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Facies Study of the Halang Formation Turbidites in Cibalung Area, Cimanggu District, Cilacap Regency, Central Java

Well preserved outcrops of the Late Miocene Early Pliocene turbidites Halang formation exposed around Cibalung area in Central Java. A continuous exposure of the Halang Formation found along Cimindi and Cikawung River are considered highly representative for detailed facies studies (Irawan).

However, it has not been extensively studied, until now. This study focuses on the sedimentation structure, vertical and lateral sedimentary facies association to determine the depositional environment of the Halang formation.

The study area lies on the Bogor Zone which is defined as a 30 km-long anticlinorium stretching in east-west trend. Anticlinorium stretching from West to East. Based on the works from Kastowo and Suwarna.

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Fold-thrust Style and Fluid Reservoir Potential of Eocene Sakesar Limestone

Surghar Range is the outer most fold-and-thrust belt of the sub- Himalayas making the easternmost extension of the Tran-Indus ranges (TIR) bifurcated by the KaIabagh fault system from the western Salt Range of North Pakistan.

The range follows east-west structural trend along the sothern margin of the Kohat plateau and switches to north-south trend along the easternmost flank of Bannu Basin. Along the range front the non-outcropping Permian to Eocene rocks underneath the Kohat and Bannu Basin are exposed at surface.

The range displays arcuate structural style in plan and exhibits distinct mountain forefront geometries along its map trace. It is characterized by south facing structures along its east-west trending segment. Whereas the north-south trending segment of the range is dominated east vergent fold-thrust assemblages.

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Potential of Salvinia molesta for Removal of Sodium in Textile Wastewater

Water is the most vital resource for all kinds of life, but it is being adversely affected both quantitatively and qualitatively. Today, most of the rivers receive millions of litre of sewage and industrial effluents containing varying characteristics from simple nutrients to highly toxic substances.

Because of increasing population and industrial developments, a huge amount of wastewater is discharged to the environment above the level that the nature can eliminate. One of the most important industrial activities in India with its magnitude of economy is the textile industry.

Textile industry discharges a complex huge volume of waste water containing various chemicals used in dyeing, printing and finishing processes. The effluent generated in different steps or processes is well beyond the standard and thus it is highly polluted and dangerous.

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Seed Germination and Seedling Survival Percentage of Shorea robusta

The greater parts of the forest area of Similipal Biosphere Reserve (SBR) are covered by moist deciduous forests, where Shorea robusta dominating in the overstorey layer. It is not only a dominant overstorey (tree) species of moist deciduous forest covers of Similipal but also one of the major species of tropical moist deciduous forests of Odisha and India.

In such forests the seeds of Sal have been the subject of great interest for the forest researchers and plantation managers as they are categorized under recalcitrant seeds and possess a very short period of viability.

Though the plants produce flowers and fruits luxuriantly in the plains and foothills, its overall natural regeneration is very poor. As a result, the Sal forests are becoming reduced its size gradually. Even worse is the fact that it exhibits largescale mortality or die-back at the seedling stage due to drought.

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Thermodynamics Reason for Dying of Urmia Lake, This is not Just an Aral Syndrome!

Urmia Lake is located in a closed basin between both the West and Eastern Azerbaijan provinces in the north-west of Iran (37°4’-38°17’ N and 45°-46°E). The shape of the lake can be seen as a semi-triangle with a maximum length of 135 km and the surface area is between 5000 and 6000 km2.

The lake in its current form can be seen in Figure 1. Urmia Lake is one of the most saline lakes, as well as the second largest, in the world and the largest lake on the Iranian Plateau. It is considered as a UNESCO biosphere and a Ramsar wetland because the lake has a unique eco-system.

Surface flow, direct rainfall, and groundwater create the majority of the sources for the lake. In the Urmia lake basin, there are twenty-one permanents and thirty-nine episodic rivers. Among the thirteen main rivers, Zarrinerood is the largest river with total annual discharge value of about 2 × 109 m3.

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A Multistage Technique to Minimize Overestimations of Slope Susceptibility at Large Spatial Scales

Rainfall induced landslides are one of the most frequent natural hazards on slanted terrains. They usually result in great economic losses and fatalities globally. Worldwide at least 32,322 deaths between 2004 and 2010 have been reported and in the United States alone, landslides cause $1-2 billion in damages and more than 25 fatalities in average each year.

Understanding, mapping, modeling and preventing the aftermath of these devastating events represents an important scientific and operational endeavor.The term “Landslide” describes the downward and outward movement of slope-forming materials that include rock, earth, and debris or a combination of these.

Although landslides are considered to be dependent on the complex interaction of several static and dynamic factors slope angle has great influence on the susceptibility of a slope to sliding. Increased slope angle usually correlates to increased likelihood of failure even if the material distribution on the slope is uniform and isotropic.

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The Impact of the Natural Hazard Flooding in East Part of Croatia-Reducing Possible Consequences

In recent decades we have witnessed more frequent and stronger weather and climate extremes: more frequent heat waves, heavy precipitation but also prolonged drought and strong winds. This trend was significant not only for Croatia but also the whole world, and it is a result of global climate changes.

This study highlights the potential health exposure risks (communicable diseases occurrence and spread) according to which recovery phase activities were taken, as well as the synoptic analysis of the weather situation which describes the terms and processes that led to a record rain fall and flooding of massive proportions.

During a weather front that passed over north-east of Croatia on May 2014, extreme rainfall events were triggered causing several severe flash floods. Ground and altitude synoptic analysis of weather situation describes the terms and processes that led to extreme rainfall.

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Ethnobotany and Ethnopharmacology, the First Step towards Bioprospecting

The Journal of Biodiversity, Bioprospecting and Development is a good context to evaluate from a scientific point of view the importance of biodiversity and its use and effects on social development, including economic development. Humans have always used natural resources because they are part of the environment and inevitably interact with it.

Foods, medicines, home all have their origin in nature. In the evolutionary process of human society, the use of natural resources based on direct experience became a use based first on cultural tradition, and later on scientific research and evidence. It is important to understand the role of ‘ethno’ sciences and other social sciences for the development of human societies, as well as the significance of science, which is reflected in scientific publications.

The conflict of interests between various parties involved in bioprospecting has already started, and social actors have a relevant role because ethno sciences are involved. We present the problem in this editorial article, in the best framework: this journal.

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Dissolved EPS Wastes as Wood Adhesive

Polystyrene foam, also known as Styrofoam or Expandable Polystyrene (EPS), is a derivative of polystyrene, which is a nonbiodegradable plastic. Polystyrene is commonly recognised for its uses, such as insulation packaging, food containers and building material. Disposal of Poly-Styrene Waste (PSW) can be problematic due to its bulky nature and highly mobile properties since EPS, comprises of 98% air and 2% polystyrene.

This dissolution method is one of the cheapest and most efficient processes for EPS waste management. The use of the dissolved EPS as construction material can be considered as a sustainable and environmentally friendly option since these materials do not contain any chlorofluorocarbons as suggested by Ref. and most likely will not contribute to the depletion of the ozone layer.

Unlike natural polymers the EPS has no nutritive value therefore it will not cause any fungal or bacterial growth as well as it poses no harmful threats to plants or animals. One potential application of dissolved polystyrene waste was to use it as wood adhesive which is the main aim of this paper.

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Analysis Of Noise And Air Pollution On Sultan Hasanuddin International Airport

The objective of this study was to analyze the level of noise and air pollution in a designated ecoairport.the parameter of measured : noise level measurement using a sound level meter, carried out in the span of one hour at 5 points, namely on the apron, waiting room-2 departure gate, gate departurelounge-5, arrivals lounge area and basement area.

moreover the indicators of air pollution instrument was measuring the level of air pollution conducted in the laboratory by sulfur dioxide (so2), nitrogendioxide (no2) and carbon monoxide (co). measurements were done in a span of one hour at 7 points namely on the apron, the departure gate lounge area 2, the area of the departure lounge gate 5, the arrival of the southern area, the northern part of the arrival area, basement, ground parking lot area.

results of the analysis of the average measurements showed that the noise level was 72.53 dba, while for the analysis of air pollution level measurement parameters, i.e sulfur dioxide (so2) is 13.748 μg/ nm3, nitrogen dioxide (no2) is 18.650 μg/nm3 and carbon monoxide (co) is 25.942 μg/nm3. based on these results the sultan hasanuddin eco-airpot due to the measured values does not pass the quality standard threshold levels of noise and air pollution levels. however, little improvment in air and noise quality can make it eg-airport.

Facies Study of the Halang Formation Turbidites in Cibalung Area, Cimanggu District, Cilacap Regency, Central Java - Indonesia

Well preserved outcrops of the Late Miocene Early Pliocene turbidites Halang formation exposed around Cibalung area in Central Java. A continuous exposure of the Halang Formation found along Cimindi and Cikawung River are considered highly representative for detailed facies studies (Irawan).

However, it has not been extensively studied, until now.This study focuses on the sedimentation structure, vertical and lateral sedimentary facies association to determine the depositional environment of the Halang formation.

The study area lies on the Bogor Zone which is defined as a 30 km-long anticlinorium stretching in east-west trend. Anticlinorium stretching from West to East. Based on the works from Kastowo and Suwarna, the oldest rock formation that discovered on the western side of North Serayu Range is the Pemali formation.

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An Automatic Deconvolution Method for Modified Gaussian Model using the Exchange Monte Carlo Method: Application to Reflectance Spectra of Synthetic Clinopyroxene

Remote sensing of reflectance spectra of Earth and other planetary bodies can be useful for identifying mineral distribution on their surfaces, especially in remote regions that are exceedingly challenging to perform field-based investigation, and those planetary surfaces yet to have in situ observation, mapping, characterization, sampling, and analyses.

Many different factors, however, can influence the surface spectra, such as various alteration and weathering processes, and observational conditions. Because a reflectance spectrum is a complex non-linear mixture of the above mentioned factors.

It is highly challenging to segregate each factor and extract the true mineral spectra, based solely on remotely observed reflectance spectra, and thus confidence in the resulting signatures should be gained by comparing with the reference spectra obtained by field or laboratory measurements.

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Geological and Archaeological Evidence of El Niño Events along the Coast of El Oro Province Ecuador: Excavations at La Emerenciana a Late

El Niño-Southern Oscillation is a band of anomalously warm ocean water related to changes in oceanic currents and trade winds. El Niño represents a general warming of surface sea temperatures along the Eastern Pacific, and a lessening or reversal of NE trade winds, creating warm humid air and reducing upwelling of cold waters resulting in dramatic perturbations to maritime and terrestrial flora and fauna.

El Niño events are differentiated by intensity and duration, or a combination of both. Particularly extreme or intense events as in 1983/84, or 1997/98 are referred to as Mega El Niño that appear to have their origins 5800 years ago. Such climatic and oceanographic perturbations have dramatic impacts upon human adaptation and sociocultural development. These climatic and oceanographic alterations create a reduction of upwelling cold waters along the west coast of South America.

These climatic changes result in dramatic perturbations to maritime and terrestrial flora and fauna and, consequently, human adaptation. El Niño events are differentiated by their intensity and duration, or a combination of both. Particularly extreme or intense events as in 1983/84, or 1997/98 are referred to as Mega El Niño which appear to have their origins 5800 years ago.

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Leaves of Vallisneria Finds Source to Anti Dermatitis: Enriching Wetland Ecosystem

An integrative ecosystem demands biological interactions which accords for survival values amongst life. The competition between different photoautotroph for resources in water body changes the succession of species which is otherwise an outcome of interactive secondary metabolites in progressive plant populations.

Virtually, various theoretical and experimental citations have been stated decades back on the role of these metabolites not only for synthetic innovations as drug adjuvant but also on natural ecospheres including aquatic macrophyte and their indulged impact on algal bloom and phytoplankton. Field evidences and literature studies confer that all primary producing organisms (cyanobacteria, micro and macro algae as well as angiosperms) are capable of producing and releasing these active compounds.

However, utilizing there in situ exudations in outward pharmaceutical implications is a fascinating aspect and a fetch for Ayurveda sciences Some Indigenous technical knowledge (ITK) and a few chemical perceptions through experimentation lead to various knowledge outsourcing to insight into the medicinal traits of many plants.

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Optimization of pH, Retention Time, Biomass Dosage in Beads and Beads Density on Textile Dye Effluent Bioremediation using Seagrass, Cymodocea rotundata Beads

Most important pollutant in effluent from food processing, cosmetics, paper, dye manufacturing, printing and textile are colour left by dyes. In the middle of these, textile industries consume large volumes of water and chemicals for wet processing of textiles.

The waste from the dying operations in the textile industries may contain dyes of various intense colours, such as dyes having the functional groups of alkene, aromatic, C-N bond, S-O bond of red colour. Some are made by inorganic molecules such as Al-O, Si-O, K-O, N=N bond which responsible for colour development in the effluent. The conventional effluent treatment systems are unable to remove recalcitrant dyes from the effluents.

The removal of dyes from effluents by the physico -chemical means such as membrane filtration advance oxidation, photo catalysis, coagulation and adsorption are often very costly and accumulation of concentrated sludge creates a disposal problem.

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Arsenic Occurrence, Ecotoxicity and its Potential Remediation

Arsenic is a naturally occurring metalloid that is widely distributed in water, soil, air and biota from natural and anthropogenic sources. Exposure to arsenic usually occurs via the ingestion, inhalation and skin contact. Arsenic has been found in drinking water in several countries worldwide which caused a major public health issue.

Cardiovascular, diabetes, and cancers are some of the general health effects that result from exposure to arsenic. There are three main groups of arsenic compounds inorganic, organic and arsine gas. These groups are based on its valence state  Arsenides/arsine gas with -3 oxidation state,Metalloid arsenic with 0 oxidation state, Arsenite trivalent compound with +3 oxidation state, and Arsenate pentavalent with +5 oxidation state.A better understanding of the chemistry of arsenic is needed to identify its toxic properties and its effects on humans and natural environment.

Oxidation states affect many properties of arsenic such as soil adsorption, soil solubility and toxicity to animals. Trivalent arsenic was dominant in the reducing conditions in flooded soils while pentavalent arsenic at oxidizing conditions in drained soils. Inorganic forms of arsenic are highly toxic compared to organic arsenic. Organic arsenic includes methylated metabolites in three forms- monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and trimethylarsine oxide. Inorganic forms of arsenic are trivalent arsenite and pentavalent arsenate.

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Comparison of the Characteristics of Low Velocity Layer (LVL) in the Mangrove Swamp and in the Upper Flood Plain Environments in the Niger Delta, using Seismic Refraction Methods

Seismic exploration involves the generation, detection, analysis and interpretation of elastic waves in the earth to study the sub-surface properties of the earth. A seismic section or profile should represent accurately the configuration of the subsurface. But due to topography and near-surface irregularities and other factors, this is not so. One of the factors is the weathered zone, otherwise called the low velocity layer (LVL) or weathered layer.

This portion of Earth affects and is impacted by various human activities such as building, excavating, tunnelling, storing or accidentally releasing hazardous materials. Moreover many of the planet’s minerals, groundwater, and cultural resources are located in the uppermost subsurface layers.This layer effectively slows down the propagation of seismic waves through the earth and hence increases their travel times.

This can lead to erroneous depth predictions of structures during final interpretation of seismic sections and reflections may appear deeper than they actually are In seismic reflection work, one very important method in eliminating this problem is the application of static corrections. But before static corrections can be determined and applied, the LVL characteristics of velocity, thickness of the LVL and its elevation must be known and thus incorporated into the processing programme of seismic reflection data.

The aims of this research are, therefore, to determine the LVL characteristics of thickness, weathering velocities and the consolidated layer velocities in the Upper Flood Plain and the Mangrove Swamp areas in the Niger Delta, and to make a comparison between these characteristics in the two zones.

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