Assessing thermal maturity of Palaeozoic rocks from reflectance of chitinozoa as constrained by geochemical indicators: an example from southern Ontario, Canada     

M. Obermajer  M.G. Fowler  F. Goodarzi  L.R. Snowdon 《Marine and Petroleum Geology》1996,13(8):907-919

The reflectance of chitinozoa (%ChR₀) was investigated as an alternative technique of determining the level of thermal maturity of organic-rich Palaeozoic rocks in southern Ontario. These sedimentary strata, which include the Ordovician Collingwood Member and the Blue Mountain Formation, as well as the Devonian Marcellus Formation, lack vitrinite precluding the application of a standard vitrinite reflectance (%VR₀) technique. ChR₀ shows a proportional increase at marginal to moderate maturities, being on average 20 to 25% higher than expected vitrinite reflectance. The reflectance data fall into a very narrow range showing a high degree of consistency for each lithostratigraphic unit. The average ChR₀ are as follows: Collingwood Mbr 0.63% (Georgian Bay area) and 0.88% (Toronto area), Blue Mountain Fm 0.92%, Marcellus Fm 0.68%. Correlation with more conventional optical and geochemical maturity parameters obtained from the same set of samples (fluorescence of Tasmanites, Leiosphaeridia and Gloeocapsomorpha alginite, Rock-Eval Tmax, extract data, distribution of terpanes and steranes in extracts) indicates that, within the area of study, the beginning of the catagenetic stage corresponds to ChR₀=0.65% (equivalent VR=0.50%) whereas the threshold of significant oil generation is reached at ChR₀=0.9% (equivalent VR=0.70%). Therefore the Blue Mountain Formation is thermally mature with respect to hydrocarbon generation throughout the whole area of study. The Collingwood shales are mature only in the Toronto area while those occurring in the Georgian Bay area as well as the Marcellus shales have yet to enter the main stage of hydrocarbon generation. This integrated approach of assessing thermal maturity shows that ChR₀, when constrained with other maturity parameters, is a very reliable indicator of thermal maturity in Lower to Middle Palaeozoic sedimentary rocks.  相似文献   

Compounding effects of human activities and climatic changes on surface water availability in Iran     

Ashraf  Samaneh  AghaKouchak  Amir  Nazemi  Ali  Mirchi  Ali  Sadegh  Mojtaba  Moftakhari  Hamed R.  Hassanzadeh  Elmira  Miao  Chi-Yuan  Madani  Kaveh  Mousavi Baygi  Mohammad  Anjileli  Hassan  Arab  Davood Reza  Norouzi  Hamid  Mazdiyasni  Omid  Azarderakhsh  Marzi  Alborzi  Aneseh  Tourian  Mohammad J.  Mehran  Ali  Farahmand  Alireza  Mallakpour  Iman 《Climatic change》2019,152(3-4):379-391

Climatic Change - By combining long-term ground-based data on water withdrawal with climate model projections, this study quantifies the compounding effects of human activities and climate change...  相似文献   

On the Performance of Computational Methods for the Assessment of Risk from Ground-Water Contamination   总被引：1，自引：0，他引：1  

Maged M. Hamed  Philip B. Bedient 《Ground water》1997,35(4):638-646

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Distribution of major, minor and trace elements in Hat Creek Deposit No. 2, British Columbia, Canada     

F. Goodarzi  E. Van Der Flier-Keller 《Chemical Geology》1988,70(4):313-333

The major-, minor- and trace-element contents of coals from Hat Creek No. 2 deposit, British Columbia, are determined using INAA and inductively coupled plasma emission spectrometry (boron only).

Al, Cr, Fe, Mn and Na were found to be inorganically bound in the coal while As, B and S are associated with the organic fraction of the coal. The rare-earth element concentrations in the coal are variable, however, the LREE/HREE ratio decreases from base to the top of the deposits. Many elements show little variation in concentration with depth; however, the gradual increase of As and S with depth appears to be rank related and indicative of progressive decrease in porosity with increasing rank.

Concentrations of B and Cr are sensitive to the environment of coal deposition, with coal deposited in a freshwater environment (Hat Creek No. 2 deposit), having low B and high Cr compared with more brackish coals.  相似文献   

Organic petrology of Hat Creek coal deposit No. 1, British Columbia     

Fariborz Goodarzi 《International Journal of Coal Geology》1985,5(4):377-396

Gell preserved monocotyledon and peeridophyta remains were found in natural bitumen frrm Iranian, tar pit and oil seeps, using reflected and fluorescence light microscopy. The plant tissue are impregnated or partially replaced by bitumens the extent of this replacement is noted.  相似文献   

An efficient tool for accelerating the numerical solution of the stochastic subsurface flow problem using neural networks     

K. H. Hamed  A. E. Hassan 《Stochastic Environmental Research and Risk Assessment (SERRA)》2000,14(6):428-448

 An efficient numerical solution for the two-dimensional groundwater flow problem using artificial neural networks (ANNs) is presented. Under stationary velocity conditions with unidirectional mean flow, the conductivity realizations and the head gradients, obtained by a traditional finite difference solution to the flow equation, are given as input-output pairs to train a neural network. The ANN is trained successfully and a certain level of recognition of the relationship between input conductivity patterns and output head gradients is achieved. The trained network produced velocity realizations that are physically plausible without solving the flow equation for each of the conductivity realizations. This is achieved in a small fraction of the time necessary for solving the flow equations. The prediction accuracy of the ANN reaches 97.5% for the longitudinal head gradient and 94.7% for the transverse gradient. Head-gradient and velocity statistics in terms of the first two moments are obtained with a very high accuracy. The cross covariances between head gradients and the fluctuating log-conductivity (log-K) and between velocity and log-K obtained with the ANN approach match very closely those obtained by a traditional numerical solution. The same is true for the velocity components auto-covariances. The results are also extended to transport simulations with very good accuracy. Spatial moments (up to the fourth) of mean-concentration plumes obtained using ANNs are in very good agreement with the traditional Monte Carlo simulations. Furthermore, the concentration second moment (concentration variance) is very close between the two approaches. Considering the fact that higher moments of concentration need more computational effort in numerical simulations, the advantage of the presented approach in saving long computational times is evident. Another advantage of the ANNs approach is the ability to generalize a trained network to conductivity distributions different from those used in training. However, the accuracy of the approach in cases with higher conductivity variances is being investigated.  相似文献   

A Comparative Study of Adaptive Neuro-Fuzzy Inference Systems in Object Detection of Complex City Scenes Using Digital Aerial Images and LiDAR Data     

Siamak Talebi Nahr  Parham Pahlavani  Hamed Amini Amirkalayi 《Journal of the Indian Society of Remote Sensing》2015,43(4):787-799

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Review: Coastal groundwater optimization—advances,challenges, and practical solutions     

Hamed Ketabchi  Behzad Ataie-Ashtiani 《Hydrogeology Journal》2015,23(6):1129-1154

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Biotic components and biostratigraphy of the Qom Formation in northern Abadeh,Sanandaj–Sirjan fore-arc basin,Iran (northeastern margin of the Tethyan Seaway)     

Ebrahim Mohammadi  Hamed Ameri 《Arabian Journal of Geosciences》2015,8(12):10789-10802

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Groundwater origins and mixing pattern in the multilayer aquifer system of the Gafsa-south mining district: a chemical and isotopic approach   总被引：3，自引：2，他引：1  

Younes Hamed  Lassaad Dassi  Meriem Tarki  Riadh Ahmadi  Khalid Mehdi  Hamed Ben Dhia 《Environmental Earth Sciences》2011,63(6):1355-1368

Major ion geochemistry and environmental isotopes were used to identify the origins and the mineralisation processes of groundwater flowing within the three aquifer levels of the multilayer system of the Gafsa-south mining district (Southwestern Tunisia). It has been demonstrated that groundwaters are characterised by a Ca–Mg–SO₄ water type. Geochemical pattern is mainly controlled by the dissolution of halite, gypsum and/or anhydrite as well as by the incongruent dissolution of dolomite. δ¹⁸O and δ²H values are much lower than the isotopic signature of regional precipitation and fall close to the meteoric water lines, indicating that groundwaters have not been significantly affected by evaporation or mineral–water reactions. The distribution of stable and radiogenic isotopes (δ¹⁸O, δ²H, δ¹³C and ¹⁴C) within the aquifer levels suggests that the deep confined aquifer receives a significant modern recharge at higher altitudes, while, the shallow unconfined aquifer has been mainly recharged under cooler paleoclimatic condition, likely during Late Pleistocene and Early Holocene humid periods. However, waters from the intermediate confined/unconfined aquifer have composite isotopic signatures, highlighting that they are derived from a mixture of the two first end-members.  相似文献