Iranian Journal of Earth Sciences: 5 (2)

Open Access Article

1 - Petrochemical Characteristics of Neogene and Quaternary Alkali Olivine Basalts from the Western Margin of the Lut Block, Eastern Iran
S. Saadat M. H. Karimpour Ch. Stern

The Nayband strike-slip fault forms the western margin of the micro-continental Lut block in Eastern Iran. Neogene and Quaternary mafic volcanic rocks collected near Tabas, along the northern part of the fault (NNF; 15 Ma), and further to the south, along the middle par More

The Nayband strike-slip fault forms the western margin of the micro-continental Lut block in Eastern Iran. Neogene and Quaternary mafic volcanic rocks collected near Tabas, along the northern part of the fault (NNF; 15 Ma), and further to the south, along the middle part of the fault (MNF; 2 Ma), are within-plate sodic-series alkali olivine basalts with high TiO2 and up to >16% normative nepheline. Their high MgO, Ni and Cr contents indicate that they crystallized from relatively primitive magmas. Their low La/Nb and Ba/Nb ratios are similar to oceanic island basalts (OIB) and unlike convergent plate boundary arc basalts (IAB). These alkali olivine basalts show enrichment in LREE relative to HREE and limited variation in Sr, Nd and Pb isotopic values which all plot in the range of OIB. Ce/Pb (>39), Nb/U (44-120) and P2O5/K2O (~0.4) ratios suggest that crustal contamination was not significant for MNF basalts. The data may be interpreted as indicating the participation of upwelling mantle asthenosphere and the deeper continental mantle lithosphere in the generation of these basalts. They formed by generally low, but variable degrees of partial mantle melting, which decreased with time from 15 Ma NNF relative to2 Ma MNF basalts. The small volume of melts that formed the MNF basalts rose to the surface along the deep Nayband strike-slip fault with no interaction with the continental crust. The larger volume of NNF basalts interacted to some degree with the crust and are associated with basaltic andesites and andesites. Manuscript profile

Open Access Article

2 - Application of glauconite and fossil palynomorphs in reconstructing the Liassic paleogeography just before the opening of the Gulf of Mexico
J. Rueda –Gaxiola

Red beds, conglomerates and salt were considered azoic and problematic rocks, but Paleopalynology and Inorganic Geochemistry proved to be useful for placing them in time and space. In the early last century, in Mexican NE region, only three Mesozoic red bed units were d More

Red beds, conglomerates and salt were considered azoic and problematic rocks, but Paleopalynology and Inorganic Geochemistry proved to be useful for placing them in time and space. In the early last century, in Mexican NE region, only three Mesozoic red bed units were differentiated, dated as Late Triassic to Late Jurassic. It was important tratigraphically to place them properly as they were considered to be the basement of the marine petroliferous sequence in some Mexican Gulf of Mexico sub-basins. Palynostratigraphic studies since 1969, and X- ray analyses since 1989 allowed to place, in time and space, the Cahuasas, Huizachal, La Joya, and La Boca red bed units, outcropping at the Huizachal-Peregrina and Huayacocotla anticlinoria and, recently, the Rosario, Conglomerado-Prieto and Cuarcítica-Cualac units at the Tlaxiaco Anticlinorium. For reconstructing the paleogeographic distribution of these red beds, their correlation permitted to place the Liassic units as deposited in a half-graben connected to an Epicontinental Sinemurian Sea. This sea, during the Middle Jurassic, was invaded by the Tethysian waters through the Hispanic Corridor formed across the new Gulf of Mexico, which originated by a hot spot with a triple junction origin. Manuscript profile

Open Access Article

3 - Shrimp Culture Impact on the Surface and Ground Water of Bangladesh
A. K. M. Munirul Haque M. Sarwar Jahan Md. Abul Kalam Azad

A case study was carried out to see the impacts of shrimp culture on the surface (pond) and ground water (tube-well) quality in three coastal sub-districts of Bagherhat Sadar, Rampal and Morrelganj of Bangladesh. The people of Rampal (100%), Morrelgonj (87.5%) and Baghe More

A case study was carried out to see the impacts of shrimp culture on the surface (pond) and ground water (tube-well) quality in three coastal sub-districts of Bagherhat Sadar, Rampal and Morrelganj of Bangladesh. The people of Rampal (100%), Morrelgonj (87.5%) and Bagherhat (75.5%) expressed that salinity of both surface and ground water increased after shrimp culture, and water becomes more turbid, odorous and less tasty compared to pre-shrimp culture scenario. The ground water pH was foo be slightly acidic (6.07– 6.71) but the surface water was mildly alkaline in nature (7.00–7.46). Ground water was more saline (1893–2673ppm) than surface water (513-2253ppm). Potassium level of surface water was very high (97-242ppm) compared to the ground water (11.73-27.37 ppm). This exceeds the WHO Guideline Value (10ppm) and the Bangladesh Standard for Drinking Water (12ppm). The pollution levels of phosphorous and iron were found to be a little higher but other pollutants like nitrate, boron and zinc were found to be very low in surface and ground water in the shrimp culture area of Bangladesh. Manuscript profile

Open Access Article

4 - Using Wind Data to Predict the Risk of Volcanic Eruption: An Example from Damavand Volcano, Iran
M. Mortazavi R.S.J. Sparks

Damavand volcano is located 60 km to the East North- East of Tehran. It is a dormant stratovolcano outcrop in the Alborz Mountains of northern Iran and is the highest mountain (5670 m) in the Middle East and West Asia. Mazandaran Province, one of the most populous provi More

Damavand volcano is located 60 km to the East North- East of Tehran. It is a dormant stratovolcano outcrop in the Alborz Mountains of northern Iran and is the highest mountain (5670 m) in the Middle East and West Asia. Mazandaran Province, one of the most populous provinces by population density, Semnan and Gorgan provinces further east are neighbours of the Damavand. Volcanism in Damavand goes back to at least 1 Ma year ago and the latest eruption occurred 7000 years ago. Tephra dispersal in volcanoes strongly depends on atmospheric information in particular wind direction and velocity in stratospheric and tropospheric levels. We present an analysis of wind data to assess the hazards that would result from tephra fall in the cities and provinces neighbouring Damavand. Atmospheric data were provided from the Meteorological stations at Mehr-Abaad airport, Wyoming University and global data sets. We examine wind data from 17 standard pressure levels which cover from 5700 meter (Damavand peak) to 31 km above sea level. If Damavand moved into a state of unrest then a major explosive eruption is a plausible scenario that should be planned for. The results confirm that the area to the south and east of volcano will be affected by tephra. Communities around the southern and eastern flanks of the volcano also have high hazard. Wind data also shows the effects of season on dispersal of tephra from a 25 km high eruption column. Tephra dispersal is dominantly towards the east in all seasons for eruption columns up to 20 km above sea level. Mazandran, Semnan and Gorgan providence could be affected in this case. At 25 km- high eruption column and during the summer there are easterly winds; therefore, the tephra would disperse toward the east. In this case Tehran could experience a tephra fall deposit Manuscript profile

Open Access Article

5 - A Seismic Factor of Radon Danger on a Case Study of Armenia
E. Saghatelyan A. Saghatelyan A. Petrosyan H. Asmaryan

For the first time, on the basis of Spitak earthquake experience (Armenia, December 1988), it was found that an earthquake causes intensive and prolonged radon releases that are quickly dispersed in the open air and that is why they are not usually registered but contra More

For the first time, on the basis of Spitak earthquake experience (Armenia, December 1988), it was found that an earthquake causes intensive and prolonged radon releases that are quickly dispersed in the open air and that is why they are not usually registered but contrastingly displayed in covered premises (such as dwelling houses, schools, kindergartens) even if they are at a considerable distance from the epicenter of the earthquake. The duration of the release includes the period starting from the first foreshock and ending with the last aftershock, i.e. several months. The radiation intensity and duration of the influence are in direct correlation with the intensity of the earthquake. The area affected by radiation is larger than the territory of Armenia. The scale of this impact on the effected population is twelve times higher than the number of people injured in the Spitak earthquake. Data collation from the 2000–2005 time period indicates that a contrasting increase in indoor radon concentrations in Yerevan (several times excessive vs. the sanitary norm) is predetermined not only by strong earthquakes (M ≥ 4.5), but also by the weak (M <4.5), small-depth (H-5-15km), regional (R ≤ 200 km from Yerevan) earthquakes and earthquake swarms occurring in the territory of Armenia, as well as in Iran and Turkey. Manuscript profile

Open Access Article

6 - Hydro-Geological Context of Mikkes Springs and Different Variations of their Flows (Morocco)
K. Belhassan

The Mikkes basin is located at the north center of Morocco. It comprises three different zones which represent diversified geologies which shelter a phreatic and confined aquifer in the Sais basin and a shallow aquifer in the Tabular Middle Atlas. The springs in the Sai More

The Mikkes basin is located at the north center of Morocco. It comprises three different zones which represent diversified geologies which shelter a phreatic and confined aquifer in the Sais basin and a shallow aquifer in the Tabular Middle Atlas. The springs in the Sais phreatic aquifer have suffered a maximum depletion. The springs with a deep or mixed origin are known as low flow variation springs. Actually, the variations of the fall of spring’s flows could be linked to a different hydro-geological context of these springs. Manuscript profile

Open Access Article

7 - Combating Climate Change: The Role of Renewable Energy and Energy Efficiency
E. Uyigue O. A. Ediang A. A. Ediang

Climate change and its possible impacts on the environment and socio-economic systems now constitute the most important environmental problem facing mankind in the 21st century. Climate change will increase poverty and hardship, endanger food security, destabilize econo More

Climate change and its possible impacts on the environment and socio-economic systems now constitute the most important environmental problem facing mankind in the 21st century. Climate change will increase poverty and hardship, endanger food security, destabilize economies, decrease food and water and create social insecurity in many countries and undermine our goals for achieving sustainable development. An in-depth analysis was carried out on the nature and characteristics of climatic changes and the roles of renewable energy and energy efficiency in combating the threat of climate change especially in relation to mitigation measures. Energy policy is therefore becoming an increasingly important tool for medium and long term planning to mitigate GHG emissions and to adapt to climate change especially in the developing countries. This paper highlights the fact that research efforts for the rest of the 21st century be directed towards harnessing renewable energies like the solar, wind and geothermal energies to replace the present day burning of fossil fuel energy for lighting, heating, cooling, manufacturing, cooking, transport, entertainment, etc. This will help to reduce the emission of green house gases (GHGs) and ozone depletion and in the long run the global warming effect. Manuscript profile

Open Access Article

8 - Geology and Mineralization of Bikilal phosphate deposit, Western Ethiopia, implication and outline of gabbro intrusion to East Africa zone
W. Mammo Ghebre

The Bikilal layered gabbro-complex is composed of zones/layers of olivine/ pyroxene gabbro and hornblende gabbro. Within the hornblende gabbro, repeated lens-like thin and elongated bodies of hornblendite are found intimately associated with massive and disseminated ilm More

The Bikilal layered gabbro-complex is composed of zones/layers of olivine/ pyroxene gabbro and hornblende gabbro. Within the hornblende gabbro, repeated lens-like thin and elongated bodies of hornblendite are found intimately associated with massive and disseminated ilmenite-magnetite bodies, in places with apatite. Petrological examination of the hornblende gabbro shows 50-55% hornblende, 40-45% plagioclase, 5-7% opaque minerals/ilmenite + magnetite/, and 5-15% apatite and that of hornblendite shows 75% hornblende, 10-15% apatite, 10-15% ilmenite and rare sulphides, and traces of Uranium. Regardless of the type of lithological units, two main zones of phosphate mineralization ,the upper and lower zones, were identified and delineated entirely based on phosphate (P2O5) assay values of chip, channel and, core samples,The strike length of the upper zone is 1600m. There are two main layers of phosphate mineralization in the upper zone; the average thickness of each layer is 30m and 40m respectively. The strike length of the lower zone is 3000m having a thickness of 60m ─ 200m. The mineable reserve of Soji-Bikilal phosphate deposit is estimated to be 181 million tons, at a grade of 3.5% P2O5. Preliminary beneficiation trial reveals commercial grade concentrate, at which the overall weight recovery, is in the range of 3-5%. The Radioactivity of Uranium has not been determined and hence re-evaluation of the phosphate rock for Uranium content should be carried out. Similar Gabbro intrusions occur in Western Ethiopia and in East Africa which should be assessed for phosphate potential to develop the fertilizer potential of the East Africa Region. Manuscript profile

Open Access Article

9 - Genetic Issues of Some of the Non Metallic Minerals in Lesser Himalaya
R. Sharma P. Joshi P. Verma

A brief account of the representative and workable industrial minerals namely magnesite, talc and barite in Lesser Himalaya, is presented here emphasizing their genesis. Deposits of magnesite and talc are found associated with Neoproterozoic, plateform type, shelf-slope More

A brief account of the representative and workable industrial minerals namely magnesite, talc and barite in Lesser Himalaya, is presented here emphasizing their genesis. Deposits of magnesite and talc are found associated with Neoproterozoic, plateform type, shelf-slope limestone-dolomite host rocks from inner Lesser Himalayan sequences. Field, textural, geochemical signatures and fluid inclusions trapped in dolomite and magnesite reveal within basin processes, in an increased burial- diagenetic environment responsible for formation of magnesite replacing dolomite. Talc is formed at the expense of magnesite and silica, and with limited dolomite involvement at transition conditions from diagenetic to metamorphism. Barite deposit is hosted within Neoproterozoic Nagthat quartzite rocks of outer Lesser Himalaya, wherein its textures, fluid inclusion, sulfur and strontium isotopic studies helped in genetic understanding. Manuscript profile

Open Access Article

10 - Estimation of erosion and sediment yield of Ekbatan Dam drainage basin with EPM, using GIS
S. Amini B. Rafiei S. Khodabakhsh M. Heydari

Soil conservation and control of erosion is a basic problem in all countries. The goal of this research is to estimate erosion and sediment yield in Ekbatan Dam drainage basin by Erosion Potential Method (EPM), using Geographic Information System (GIS). The basin is loc More

Soil conservation and control of erosion is a basic problem in all countries. The goal of this research is to estimate erosion and sediment yield in Ekbatan Dam drainage basin by Erosion Potential Method (EPM), using Geographic Information System (GIS). The basin is located in Hamedan Province, west of Iran, in a cold and semi- arid region, with an average annual rainfall of 334mm. The study area is about 218 km2 and is divided into 8 sub- basins. Sub- basins 1 and 6 are the largest (49.14 km2), and smallest (9.92km2), respectively. Elevation ranges between 1960 to 3580 m. The litho-units include schist, granite, hornfels, limestone, sandstone, (Pre- Jurassic to Neogene in age), conglomerate, and recent alluvium. Most sediment in the basin is generated from erosion of schist. The main factors in the EPM (slope average percent, erosion, rock and soil erosion and land- use) were evaluated using GIS software. Data layers used in this study were created from topographic, homorain, homotemp, geology, lithology maps, landsat TM digital images, and field observations. According to calculated results, the coefficient of erosion and sediment yield (z) for this basin fall into moderate and heavy erosion classes. For avoiding soil erosion in this basin, therefore, soil conservation operations should be performed. Manuscript profile

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