ali moradpour

The pillow lavas and dyke swarm of Harsin-Nurabad and Miyanrahan are part of Kermanshah Ophiolite complex. Diabasic dykes with ophitic, doleritic and glomeroporphyritic textures consist of zoned plagioclase and clinopyroxen and pillow lavas have intergranular and microporphyritic textures with hyalomicrolitic matrix and consist of plagioclase, augite-diopside and pseudomorphic olivines.The resalts of N-MORB-normalized multielement and chondrite-normalized REE patterns indicate that these rocks not formed in supra-subduction zone but overall geochemistry of Gashor pillow baslte and diabasic dykes resembles that of alkaline basalts generated at within-plate ocean island settings (OIB), meanwhile Tamark and Miyanrahan pillow baslte show P-MORB geochemical signature. MORB evidence in studied rocks is interpreted to be the partial melting of an OIB-type enriched source led to the production of the Gashor and diabasic dykes alkaline basalts whereas the partial melting of MORB-type mantle heterogeneously modified by OIB-type components resulted in the production of Tamark and Miyanrahan P-MORBs. Therefore, it may be considered that, southern Neo-Tethys was characterized by an intermediate rifted margin type where asymmetrical rifting, exhumed sub-continental upper mantle provided combination of continental margin- and plume-type in the investigated ophiolites.

Land use/cover change at the geological marl formations, especially the conversion of forest and rangeland areas to rain-fed lands and subsequent improper tillage practice has led to severe soil erosion and sedimentation, soil moisture lost, dust-blown, global warming, and water pollution. The current study aims to prepare the spatial distribution of marl formation in Kermanshah province in Iran and to assess dominant land-use, plant cover, slope, and erosion features using satellite image (SPOT 2000) and field survey. The field data have been analyzed through ArcGIS software. The results of this study reveal that there are eight major marls formations in Kermanshah province including Amiran, Aghajari, Gachsaran, Gurpi, Talezangh, Kashkan, Pabdeh, and Mishan occupying about 24.21 % of province areas. Among these formations, three formations including Amiran, Kashkan, and Aghajari are the most vulnerable to degradation due to topographic conditions, high solubility, and improper land-use practices. The sensitive facies of Amiran and Kashkan Formations are more prominent in the forest and rain-fed areas with hill slope conditions. In these areas, deforestation, illegal charcoal extraction, improper agricultural and non-agricultural activities resulted in the dissolution of sensitive layered and consequently landslide incidents. Thus during each effective rainfall occurrence, there is severe erosion and siltation deliver fresh sediment in lower drainage systems affecting road, brigs, and farmlands. In gentle slope, this process causes head-cut and gully development. Aghajari formation, which covers a wide range of winter pastures in Kermanshah province, has a high potential of dissolution due to its mineralogical and soil properties increasing soil erosion and sediment yield. It is concluded that severe land use/cover change at marl formation of Zagros areas are the factors sensitive to soil erosion, sedimentation and flood hazard as well as the solution of serous crises such water deficiency and desertification.

 Geological Marl formations and their deposits are more sensitive to degradation and soil erosion factors. The considerable areas of Zagros regions in Iran comprise marl formations dominated by forest and rangeland land uses. These marls are different condition of topography and land use/cover, while they are characterized by high level of clay and slit contents and dominant swell-shrink clay minerals. Thus, the soils originated from these marl formations are vulnerable to plant cover degradation causing severe erosion, sediment and flood hazards. Landus in marly areas are forest and rangeland, hence; converting them to rain-fed areas and subsequently improper human practices such as heavy tillage and civil activities cause gully erosion and other soil erosion features, landslide occurrences, soil moisture lost and organic carbon emission. However, survey on marl formations in terms of land use/cove and dominant soil erosion at local scale are necessary steps to control environmental hazards, especially erosion, sediment, flood as well as drought, dust and water shortage managements in watersheds of west and east west of Iran. The present study aims to determinate the marl formation areas and to make a map for their distribution recognizing, some important local features like erosion in Kermanshah province (a part of upper Karkheh catchment) in Iran which were carried out during 2017-2020.  

 This research conducted in Kermanshah province comprising verity of geological formations mainly marl deposits which are the hilly and plain topography. In other to achieve this research, the border of each marl formation was mapped using basal geological map and field verification. Next the dominant erosion feature was determined using satellite image (SPOT), but the land use was mapped through Landsat 8 (2015). Finally, field survey carried out for exploring details of land use and erosion features using GPS. The soil erosion features were inter-rill, rill, gully and landslide. Furthermore, land use was forest, rangeland and agricultural areas.  The spatial distribution and area of main erosion feature and land use within each marl formation was mapped using ArcGIS.

The findings reveal that there are eight major marl formations in Kermanshah province including Amiran, Aghajari, Gachsaran, Gurpi, Talezangh, Kashkan, Pabdeh, and Mishan occupying approximately 603 million ha (24.21 % of province areas).Among these formations, three formations of Amiran, Kashkan, and Aghajari are the most vulnerable to degradation due to higher area, topographic conditions, high solubility, and improper land-use practices. Field verification showed that solubility phenomenon in both Kaskan and Amiran formations is considerable where, forest and rangeland are degraded or rain-fed areas is subjected to up-down the slope tillage practice. They are more sensitive to land use change and field survey showed severe inter-rill, rill and landslide incidence where subjected to converting forest, tillage practice, charcoal extraction and improper civil activities. In some areas, that forest is wholly cleared, after each effective rainfall occurrence, fresh sediment from hill slope of Amiran and Kashkan damage the road, bridge, riverside and lowland agricultural areas. Moreover, in plane areas, dissolve phenomenon contributes to head-cut activity developing of gully erosion. For instance, in Bujan area (SW Kermanshah city), sever tunneling erosion and landslide are delivered the fresh sediment comprising greenish clay and slits fractions during rainfall. This sediment moves down through runoff in parallel to slope furrow of tillage at the rain-fed lands. Consequently, this sediment contaminates surface water, accelerates local flood hazard and covers farmlands in lower parts. It can be said that the deforestation rate is less visible in this province. Therefore, as one of the upstream branches of Karkheh basin, it has a key origin of flood occurrence and sediment yield and its accelerating damages in Lorestan (Pol-e Dokhtar) and Khuzestan provinces. This destruction continues in an astonishing way, away from improper management and monitoring. Aghajari formation, which covers a wide range of winter pastures in Ghasr-e-shirin, has a high potential of dissolution phenomenon due to its mineralogical and soil properties increasing soil erosion and sediment yield. It is more vulnerable, where subjected to land use change, particularly converting rangeland to irrigation lands.

According to findings, most of the marl formations in Kermanshah province have more outcrops in the upper and middle parts of watersheds and continue in Lorestan, Ilam and Khuzestan provinces which induces same conditions for environmental hazards such as floods, soil erosion and dust phenomena. The reason for the destruction of these marl formations is the change in land use, especially the conversion of forests and rangeland to rain-fed areas causing various forms of erosion, including dissolution, rill, gully and landslides. Field studies reveal that most facies of these marl formations contain clay, silt and shale with thin to medium sandstone layers. Due to mineralogical property and high amounts of clay and silt fractions as well as topographic factors, they are prone to dissolution, erosion and landslides hazard, which are increased by land use change in forest and rangeland areas, vegetation destruction and improper tillage practice. In this condition, fine-grained sediments reach the drainage system during rainfall time. The consequencs of this process, in addition to sediment, are the flood hazard, water shortages impacting proper management of such crises in the Zagros regions. In Qasr-e-shirin areas, extensive land use change at Aghajari formation not only causes soil erosion, sediment and flood problems, but also potentially is the dust blown origin due to the prevailing wind direction (from east to west), that can affect Kermanshah, Lorestan, Hemedan and Markazi province of Iran.

The basic rocks in the Serowarea(northwest of Urmia) are exposed to young alluvium (Quaternary). These rocks are part of the metamorphic Sanandaj-Sirjan belt. The study area is composed of various igneous, metamorphic and sedimentary rocks and the age range is from Precambrian to the present era.

In order to perform a chemistry study of northern Serowlavas, 10 rock samples were analyzed by the ICP-MS method in Bureau Veritas laboratory in Canada. Also, olivine, orthopyroxene, clinopyroxene and plagioclase minerals were analyzed at the Institute of Geology and Geophysics of the Chinese Academy of Sciences (IGGCAS) by the JEOL JXA-81 microprobe electron analyzer.

Field studies and petrographic observations indicate that the rocks of the Serow area can be divided into alkaline basalt, trachy- basalt and trachy- andesite. One of the major textures in these rocks is porphyry texture and to a lesser extent trachyte texture. Plagioclase, orthopyroxene, clinopyroxene, olivine and amphibole are the minerals that make up these rocks. Calcite mineral is the most important and main secondary mineral in these rocks, which often fills the cavities and gives them amygdale tissue.The results of the chemical analysis of the studied rocks show that their composition is basalt to trachy- andesite-basalt and they are alkaline and within plate basalts type. Examination of rare earth elements in these rocks show that the studied samples have little differentiation in rare earth elements, especially in HREEs. But, LILEs are more differentiated and enriched. Therefore, in the normalized pattern, they show a decreasing trend from Ba to Yb. Enrichment in LILEs and LREEs compared to HFSEs and HREEs, presence of negative anomalies in Ta, Nb, P and Ti elements along with enrichment of Rb and Ba elements can be due to the role of fluids in subduction zones. The ratios of Smn/Lan, Lan/Ybn  and Smn/Ybn can be used as evidence of low melting rate and the presence of garnet in the residual melting. The La/Sm versus Sm/Yb diagram has been used to determine the degree of melting of the source rock, showing the degree of melting of 1% of the source rock with spinel peridotite composition.The results of electron microprobe analysis of olivine mineral show that the average value of Fo in alkaline basalts is 85.77 (Fo 85.77) and in andesite – basalts it is 82.29 (Fo 82.29). Clinopyroxene mineral has diopside composition in alkaline basalt rocks and diopside augite composition in basaltic andesite rocks. Orthopyroxenes ranges from En 56.84-57.03, Wo3.14-3.33 and Fs 39.36-39.54 .The composition of plagioclase in alkali and andesitic basalts is in the labradorite range.

The basic rocks in the Serow are consistent of olivine + clinopyroxene + plagioclase ± orthopyroxene ± amphibole. The results of the geochemical analysis reveal the alkaline nature and intra plate setting and volcanic arcs of these rocks. Pyroxene mineral chemistry shows relatively high oxygen pressure conditions and a water content of 10% during the crystallization of clinopyroxenes. Based on the calculations and geothermobarometric diagrams, the formation temperature of clinopyroxene in alkali basalts and andesitic basalts is 1000 to 1250˚C and their estimated pressure is less than 5 Kbar. From the tectonic point of view, it seems that the formation of these rocks is associated with processes following the complete closure of the Neo-Tethys Ocean and the continental collision.

Oil products are considered to be life-threatening factors in the ecosystem due to their contents of organic compounds, sulfide, sulfur, heavy metals, and various circular hydrocarbons, organic solvents, aromatic compounds, linear formaldehyde, fats, and grease. The present study aimed to investigate the soil surrounding Kermanshah Refinery, Iran and estimate the density of various heavy metals and their pollution sources, including arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), nickel (Ni), zinc (Zn), lead (Pb), copper (Cu), scandium (Sc), and vanadium (V). The geoaccumulation index indicated that the intensity of the refinery soil had variable degrees of pollution, ranging from no pollution to average pollution with chromium and nickel. In addition, the enrichment index showed average enrichment for cadmium (station 14), copper (stations two, 11, 13, and 14), lead (stations six and 13), zinc (stations two, six, 11, and 13), and chromium (stations 6-15). On the other hand, the pollution bar index of chromium, copper, nickel, zinc, and lead was estimated to be higher than one, which confirmed unacceptable soil quality and the presence of soil pollution in the region. According to the results of Pearson's correlation-coefficient, nickel pollution was significantly correlated with chromium and scandium pollution, while cobalt pollution was associated with vanadium and chromium pollution. Moreover, a significant correlation was observed between zinc and copper pollution, which indicated the equal pollution source or similar geochemical behaviors of these elements toward each other. Since vanadium is considered to be an oil pollution index, it could be concluded that high pollution with this element and chromium may arise from petroleum in the studied region.

In recent decades, soil pollution with petroleum hydrocarbons in oil-rich countries (such as Iran) has been one of the most challenging issues. In these countries with petroleum industries, mines of oil exploration, refineries, etc., leakage from tanks or pipelines of oil transmission due to corrosion and damage bring about oil pollution for the soil. This study aimed at evaluating and measuring the amount of heavy metals in the soil of Kermanshah Refinery and statistical analysis in order to locate high-risk areas in terms of pollution caused by oil leaks, extraction, refining, and transportation. Therefore; 15 samples of surrounded soil of Kermanshah Refinery were analyzed to determine soil pollution with petroleum compounds. According to results of ICP-MS analysis of soil samples, the process of heavy metal changes in the soil of Kermanshah Refinery was Cr>Zn>Ni>V>Cu>Pb>Co>Sc>As>Cd. Geo accumulation index indicated that the intensity of the refinery soil is classified in the range of no pollution to average with reference to chromium and nickel. Besides, the finding from enrichment factor indicated the average enrichment of the region soil by chromium and lead. Moreover, it confirmed that enrichment in lead and copper has anthropogenic origin. Pollution load index of chromium, nickel, zinc, copper, and lead showed soil pollution to these metals. Zoning map of heavy metal density in the region soil demonstrates that high density of the elements in some stations is related to the petroleum leakage from installations and storage tank.

Soil is regarded as one of the natural slow biodegradable source which plays an important role in the cycle of mineral and organic elements. As a dynamic ecosystem, it provides the life for big and small creatures, so removing its pollution is of considerable attention. The pollution of heavy metals not only affects directly the physical and chemical features of soil and reduces biological activities and access to nutrition materials in soil, but also is considered as a serious danger for human health. In fact, they can enter food chain or penetrate underground water sources.Iran is one of the oil-rich countries in the world in which high amount of oil is extracted in southern regions and refined in other places yearly. Once oil is extracted, transmitted and refined, its release in the soil causes pollution. A group of soil pollutant sources is related to oil discoveries, production, saving, transmission, distribution and final burial of wastes. If these industries are pollutants, they will cause dangers. The increase of soil pollution by heavy metals has led to a lot of research.
Kermanshah province is located to the west of Iran sharing borders with Lorestan, Kurdistan, Ilam and Hamedan and an international border with Iraq. Its geographical coordinate is between (33˚37̕to 35˚17̕) northern longitude and (45˚20̕ to 48˚01̕) eastern longitude. Since Kermanshah Refinery is built on alluvial terraces, fans of new low foothills and Inceptisols and Vertisols,15 samples of surrounded soil were collected by an iron shovel from the depth of 15 to 25 cm. ICP-MS method, were used to analyze and determine the density of heavy elements in of the samples. Grinded to the sizes less than 4 mm by crusher, the samples were become powder to the size of 75 microns (200 mesh) by disc mill. Weighing the samples by Teflon pipes in digest 4 acid, hydrochloric, perchloric, nitric and choloridric acid were added to the samples equally. All samples were kept in Hot Box case. After complete digest operations, the samples were cold in the environment temperature and achieved volume by distilled water.
The findings from geo-accumulation index shows that the intensity of Refinery soil is classified in the range of no pollution to average regarding chromium and nickel. Besides, enrichment index indicates average enrichment for cadmium (station 14), copper (stations 13, 11, 2 and 14), lead (stations 6 and 13), zinc (stations 11, 6, 2, and 13) and chromium (the stations from 6 to 15). In addition, pollution bar index of chromium, copper, nickel, zinc and lead is more than 1 proving the inappropriate soil quality and soil pollution of the region. However, chromium has the most considerable value, 2/75. Average value of EF is less than 2 for arsenic, cobalt and vanadium proving that the region does not show enrichment for the aforesaid elements. Enrichment index values for cadmium, chromium, copper, nickel, lead and zinc are between 2 to 5 indicating average enrichment of these samples than other metals. Since enrichment element for these sample are higher than 2, they have anthropogenic source.
According to Pearson correlation coefficient, there is a high correlation between nickel and chromium, scandium and cobalt, vanadium and chromium, and zinc and copper and lead indicating the equal source or similar geochemical behavior of the elements toward each other. Since vanadium is considered as one the oil pollution indices, it can be concluded that high pollution of this element and chromium around the region comes from petroleum.
The findings from the present study shows that soil surrounded Kermanshah Refinery are polluted to some elements. According to the values of geoaccumulation in the studying area, elements nickel and chromium have pollution. The finding from enrichment factor indicates the average enrichment of the region soil by chromium and lead. Besides, enrichment factor higher than 2 for lead and copper proves anthropogenic interference factors in the region pollution to them. The results from pollution bar for chromium, nickel, zinc, copper and lead is more than 1 indicating soil pollution to these metals. Pearson correlation coefficient reveals that there is a high correlation among vanadium, cobalt, chromium, and nickel proving same origin. Making zoning map of heavy metal density in the region soil demonstrates that high density of the elements in some stations is related to petroleum producing installations and storage tank. Cluster analysis shows the division of the elements into 7 clusters. Besides, the elements with structural relationship are related in next subcategories. Clusters 6 and 7 together indicate the same origin for these elements. Since vanadium is derived from oil compound, it can be concluded that chromium and nickel pollution have the same pollution origin with oil compounds. Factor analysis introduces 3 main factors in which the first factor with total 40/1% of total variance is the most effective factor in density of the soil elements. This factor has a high positive correlation with Sc, V, Ni, Cr, and Co proving the same density origin with petroleum compound.