Drill cutting samples (n = 92) from the Devonian Awaynat Wanin Formation and Silurian Tanezzuft Formation, sampled from three wells F1, G1 and H1, locate in the northern edge of the Murzuq basin (approximately 700 kilometers south of Tripoli). The studied samples were analyzed in the objective of their organic geochemical assessment such as the type of organic matter, depositional conditions and thermal maturity level. A bulk geochemical parameters and precise biomarkers were estimated, using chromatography-mass spectrometry (GC-MS) to reveal a diversity of their geochemical characterizations. The rock formations are having varied organic matter contents, ranged from fair to excellent. The total organic carbon (TOC) reached about 9.1 wt%, ranging from 0.6 to 2.93 wt% (Awaynat Wanin), 0.5 to 2.54 wt% (Tanezzuft) and 0.52 to 9.1 wt% (Hot Shale). The cutting samples are ranged oil-prone organic matter (OM) of hydrogen index (HI) ranged between 98 –396 mg HC/g TOC, related kerogen types are type II and II/III, with oxygen index (OI): 6 - 190 with one sample have value of 366 mg CO2/g. Thermal maturity of these source rocks is different, ranging from immature to mature and oil window in the most of Tanezzuft Formation and Hot Shale samples, as reflected from the production index data (PI: 0.08 - 034). Tmax and vitrinite reflectance Ro% data (Tmax: 435 – 454 & Ro%: 0.46 - 1.38) for the Awaynat Wanin. Biomarker ratios of specific hydrocarbons extracted from represented samples (n = 9), were moreover used to study thermal maturity level and depositional environments. Pristine/Phytane (Pr/Ph) ratios of 1.65 - 2.23 indicated anoxic to suboxic conditions of depositional marine shale and lacustrine source rock.

This search aims to apply developed geochemical methods to a number of oils and source rock extracts to better establish the features of ancient environments that occurred in the Murzuq basin. Geochemical and geophysical approaches were used to confirm further a source contribution from other Paleozoic formations to hydrocarbon accumulations in the basin. One hundred and forty rock units were collected from B1-NC151, D1-NC174, A1-NC 76, D1-NC 151, F1-NC58, A1-NC 186, P1-NC 101, D1-NC 58, H1-NC58 and A1-NC58 wells. Seven crude oils were collocated A1-NC186, B1-NC186, E2-NC101, F3-NC174, A10-NC115, B10-NC115 and H10-NC115 wells. A geochemical assessment of the studied rocks and oils was done by means of geochemical parameters of total organic carbon (TOC), Rock-Eval analysis, detailed-various biomarkers and stable carbon isotope. The TOC values from B1-NC151 range 0.40% to 8.5%, A1-NC186 0.3% and 1.45, A1-NC76 0.39% to 0.74%, D1-NC151 0.40% to 2.00% to F1-NC58 0.40% to 1.12%. D1_NC174 0.30% to 10 %, P1-NC101 0.80% to 1.35%, D1-NC58 0.5% to 1.10%, H1-NC58 0.20% to 3.50%, A1-NC58 0.40% to 1.60%. The categories of organic matter from rock-eval pyrolysis statistics point to that type II kerogen is the main type, in association with type III, and no of type I kerogen recognized. Vitrinite reflectance (%Ro), Tmax and Spore colour index (SCI) as thermal maturity parameters reflect that the measured rock units are have different maturation levels, ranging from immature to mature sources. acritarchs distribution for most samples could be recognized and Palynomorphs are uncommon. Pristane to phytane ratios (> 1) revealed marine shale to lacustrine of environmental deposition. The Stable carbon isotope (δ 13C) values of seven rock-extract samples are -30.98‰ and -29.14‰ of saturates and -29.86‰ to -28.37‰ aromatic fractions. The oil saturate hydrocarbon fractions range between -29.36‰ to -28.67‰ and aromatic are among -29.98 ‰ to -29.55 ‰. The δ 13C data in both rock extractions and crude oils are closer to each other, typical in sign of Paleozoic age. It is clear that the base of Tanezzuft Formation (Hot shale) is considered the main source rocks. The Devonian Awaynat Wanin Formation as well locally holds sufficient oil prone kerogen to consider as potential source rocks. Ordovician Mamuniyat Formation shales may poorly contain oil prone kerogen to be addressed in future studies. An assessment of the correlations between the oils and potential source rocks and between the oils themselves indicated that most of the rocks extracts were broadly similar to most of the oils and supported by carbon stable isotope analysis results. 

We have described the development of electrochemical nano sensor for the detection of total arsenic in groundwater, soil, food and honey samples based on the formation of gold nanoparticles. Screen printed carbon electrodes were modified with gold nanoparticles and linked with 1,6-hexanedithiol self-assembled monolayers. The electrodeposition of Au nanoparticles was applied in 10 mL of the solution that totally cover the screen-printed carbon electrode while applying a constant potential of –0.4 V (vs. Ag within SPCE) for 600 sec. Cyclic voltammetry was used to characterize the gold nanoparticles before and after modified with 1,6-hexanedithiol self-assembled monolayers on screen printed carbon electrode. Square wave anodic stripping voltammetry with multi point standard addition method was examined for the detection of As(III) and As(V) on Au NPs-1,6-hexanedithiol modified screen printed carbon electrode under optimized conditions. As(III) and As(V) was firstly, deposited for 60 seconds by the reduction of arsenic in buffer solution: (citric acid, sodium chloride and ascorbic acid pH 2.0), followed by As stripping between –0.20 and 0.35 V at the following parameters: scan rate: 100 mV s–1, frequency: 60 Hz, amplitude: 0.025 V and increment: 5.0 mV. it was found that Au-NPs with 1,6-hexanedithiol modified screen-printed carbon electrode had a highest anodic stripping peak current at 0.201 V. The limit of detection value for arsenic was identified to be 1.7 ng ml –1. Also, the electrochemical nanosensor showed excellent reproducibility and high stability. The developed method was successfully applied to detect total arsenic in ground water, soil and honey samples.

This study had been performed in Sabratha area to assign some physical, chemical and biological characteristics for underground water and to find out its propriety for drinking. The study area was divided into ten locality: Dahman, Al- Khatatba, Aljabbar, Subratha center, Soug Al-Alalgah, Aldababshiah, Alnahdah, Tillil, Altunaibat, and Aggar. Forty eight samples of underground water has been collected in the study area. Five wells from each site were chosen except in Subratha center, where three wells were chosen. After performing the necessary analysis it became clear that the total dissolved salts concentration in 93.75% of the wells exceeded the allowable limit for drinking water, the highest was found to 4444.060 PPM in Tillil area, in addition to that, it was found that 81.25% of the wells, water, exceeded the allowable limits for sulpher concentration in drinking water. It was found that the concentration of the chloride (Cl ‾) exceeded the allowable limit for drinking water in 93.75 % of the wells, and the concentration of nitrite (NO2‾) exceeded the allowable limit in 8.3 % of the wells, while the concentration of nitrate ion ( NO3‾ ), in all wells were compatible with the Libyan and International specifications. The Calcium ion (Ca+2) exceeded the allowable limit in 87.5% of the wells. We can found also that, the concentration of magnesium element (Mg) exceeded the allowable limit in 79.1% of the wells. As for the sodium (Na+) concentration, it exceeded the allowable limit for drinking water in 95.8% of the wells, the highest was recorded in Sabratha center (7782 ppm). Some of the wells were polluted from the biological aspect, that was due to the contamination by sewage waters. In this study we found that, 39.58% of the well waters were polluted and not compatible to the international and Libyan standard specifications for drinking water, while we found that 60.41% of the wells were not polluted and were compatible with the standards. From the chemical aspect we found that, the most wells in the study area were not good for drinking, especially those located to the north, since they are near the sea and they merge with sea water . We also can notice that many of the wells were not good for drinking from the biological aspect, so we recommend to perform chemical and biological analysis before using the underground waters for domestic, agricultural and industrial objectives. Key words: Underground water, chemical pollution, biological pollution, Sabratha, Libya

Evapotranspiration calculation is an important matter due to agricultural reasons, but also for understanding water resources and runoff amount in a certain territory. Two CMIP5 multimodal projections (2011–2040 and 2041–2070) and land-cover pattern were used to analyse the seasonal and annual crop evapotranspiration trend in Turkey. The spatial distribution of crop evapotranspiration related to the initial season, mid-season, end season and cold season were computed through a geographical information system. The maximum crop evapotranspirations were found in the mid-season for present and future, with 1,072 and 1,241 mm respectively. For the future period, an increase in the spatial distribution of crop evapotranspiration was depicted in several places due to climate warming, mainly in the southern and southeastern areas of Turkey and on the Mediterranean coast. The minimum seasonal crop evapotranspirations fell to below 154 and 164 mm in the present and future respectively. The annual crop evapotranspiration increased from 1,675 to 1,944 mm from present to future and the significant values of absolute changes were identified in the western, eastern and southeastern regions of Turkey. The findings are useful for scientists in the climate, hydrology and agriculture fields, but also for management decisions.