Effects of Cone Penetrometer Testing on Shallow Hydrogeology at a Contaminated Site

Penetration testing is a popular and instantaneous technique for subsurface mapping, contaminant tracking, and the determination of soil characteristics. While the small footprint and reproducibility of cone penetrometer testing makes it an ideal method for in-situ subsurface investigations at contaminated sites, the effects to local shallow groundwater wells and measurable influence on monitoring networks common at contaminated sites is unknown. Physical and geochemical parameters associated with cone penetrometer testing were measured from a transect of shallow groundwater monitoring wells adjacent to penetrometer testing. For wells screened above the depth of cone refusal, the physical advancement and retraction of the cone had a significant effect (p < 0.01) on water level for several pushes within 10 meters of a monitoring well, and a measured increase in specific conductivity. No effect on geochemistry or water level was observed in continuous monitoring data from wells screened below the depth of cone refusal, but variability in specific conductivity from these wells during penetration testing was only a fraction of the natural variation measured during precipitation events. Continuous measurements of specific conductivity and water level demonstrated that the effects of penetration testing have limited spatial and temporal distributions with a null effect post-testing.

Changing Tropical Estuarine Sedimentary Environments with Time and Metals Contamination, Cest Coast of India

Estuaries are one of the major sub-environments of the coastal zone wherein freshwaters interact and mix with saline waters, and facilitate deposition of finer sediments, organic matter, and metals. Intertidal mudflat and mangrove sediment cores collected from estuaries along the central west coast of India were investigated for various sedimentological and geochemical parameters to understand the changes in the sedimentary depositional environments and various factors influencing the processes. Additionally, estuarine biota was examined to understand the bioaccumulation of metals with respect to bioavailability. The results indicated considerable changes in the depositional environments with time owing to sea-level changes; geomorphology of the estuaries; rainfall and river runoff; anthropogenic activities including construction of dams and bridges. The sediments in the estuaries are considerably polluted by metals and pose toxicity risks to the estuarine biota due to high metal bioavailability. Marine gastropods and mangrove plants act as prospective bio-indicators, and the bioremediation potential of mangroves for contaminated sediments was identified. Metal bioaccumulation in edible benthic biota can be harmful to the human health.

Quantitative Geochemical Prediction from Spectral Measurements and Its Application to Spatially Dispersed Spectral Data

The efficacy of predicting geochemical parameters with a 2-chain workflow using spectral data as the initial input is evaluated. Spectral measurements spanning the approximate 400–25000 nm spectral range are used to train a workflow consisting of a non-negative matrix function (NMF) step, for data reduction, and a random forest regression (RFR) to predict eight geochemical parameters. Approximately 175,000 spectra with their corresponding chemical analysis were available for training, testing and validation purposes. The samples and their spectral and chemical parameters represent 9399 drillcore. Of those, approximately 20,000 spectra and their accompanying analysis were used for training and 5000 for model validation. The remaining pairwise data (150,000 samples) were used for testing of the method. The data are distributed over two large spatial extents (980 km2 and 3025 km2, respectively) and allowed the proposed method to be tested against samples that are spatially distant from the initial training points. Global R2 scores and wt.% RMSE on the 150,000 validation samples are Fe (0.95/3.01), SiO2 (0.96/3.77), Al2O3 (0.92/1.27), TiO (0.68/0.13), CaO (0.89/0.41), MgO (0.87/0.35), K2O (0.65/0.21) and LOI (0.90/1.14), given as Parameter (R2/RMSE), and demonstrate that the proposed method is capable of predicting the eight parameters and is stable enough, in the environment tested, to extend beyond the training sets initial spatial location.

Geochemical Evaluation of Formation Water, Mauddud Reservoir, Khabbaz Oilfield, Kirkuk Area, Northern Iraq

In this study, formation-water samples were collected by NOC Staff, during drilling time, from the Mauddud Formation reservoir of the Khabbaz Oilfield, for this reason four samples from four wells; Kz-3, Kz-4, Kz-7, and Kz-23 were selected to geochemical analysis. Analyzed geochemical parameters include TDS and the concentrations of the different dissolved cations and anions present in brines (Ca+2, Mg+2, Na+1, SO4-2, Cl-1, HCO3-1, and NaCl). Variations among the resulted data are discussed by comparison with other Cretaceous Brines. Geochemical ratios of Na/Cl, (Na-Cl)/SO4) and (Cl-Na)/Mg+2 was calculated for formation water classification following Bojarski, (1970). The calculated geochemical ratios of the studied samples in the studied four wells indicate that all of these waters are "chloride calcium" type under subsurface conditions, this type reflect closed system isolated associations reservoir, which are becoming high hydrostatic in deeper zones without influence by infiltration waters. A major transversal fault cutting the structure at its SE plunge had participated in the dilution of the Mauddud reservoir brine effectively.

Quantitative Geochemical Prediction from Spectral Measurements and its Application to Spatially Dispersed Spectral Data

The efficacy of predicting geochemical parameters with a 2-chain workflow using spectral data as the initial input is evaluated. Spectral measurements spanning the approximate 400-25000nm spectral range are used to train a workflow consisting of a non-negative matrix function (NMF) step, for data reduction, and a random forest regression (RFR) to predict 8 geochemical parameters. Approximately 175000 spectra with their corresponding chemical analysis were available for training, testing and validation purposes. The samples and their spectral and chemical parameters represent 9399 drillcore. Of those, approximately 20000 spectra and their accompanying analysis were used for training and 5000 for model validation. The remaining pairwise data (150000 samples) were used for testing of the method. The data are distributed over 2 large spatial extents (980 km2 and 3025 km2 respectively) and allowed the proposed method to be tested against samples that are spatially distant from the initial training points. Global R2 scores and wt.% RMSE on the 150000 validation samples are Fe(0.95/3.01), SiO2(0.96/3.77), Al2O3(0.92/1.27), TiO(0.68/0.13), CaO(0.89/0.41), MgO(0.87/0.35), K2O(0.65/0.21) and LOI(0.90/1.14), given as Parameter(R2/RMSE), and demonstrate that the proposed method is capable of predicting the 8 parameters and is stable enough, in the environment tested, to extend beyond the training sets initial spatial location.

The millstone trade from the most exploited Italian volcanic areas: an overview from the phoenicians to the roman period

Lavas were widely used in antiquity to produce millstones. This is mainly due to their superior properties for grinding cereals and availability when compared with other rock-types. In the past four decades, several studies have been published about lava millstones discovered in subaerial and submarine archaeological sites of the Central-Western Mediterranean. Although the morphological evidence of old quarries is rarely present, all these studies were aimed at recognizing provenance and manufacturing areas of the volcanic raw material. Typologies of grinding tools coexisted in different periods, even if some technological developments marked transitions between cultures. The main chronology is: Archaic saddle quern, Greek hopper-rubber (Olynthian), small to medium size rotary device (Morgantina type) and large hourglass rotary millstone (Pompeian style). Potential volcanic sources are widespread throughout the entire Mediterranean region, but two main Italian quarrying areas of volcanic rocks for the manufacture of millstones from the Phoenician to the Roman period were pointed out. These are the Latium-Umbria border in Central Italy, and Sicily (Eastern Sicily and Sicilian Channel) in Southern Italy. In detail, analysis of the lava lithotypes shows that grinding tools were mainly constructed of: (i) a leucite phonolite of the so called “Orvieto quarries” between the localities of Sugano and Buonviaggio in the Roman Volcanic Province (High-K alkaline series); (ii) hawaiites and mugearites (Na-alkaline series) from Etna volcano; (iii) basalts (Tholeiitic/Transitional series) of the Hyblaean Mountains and (iv) basalts (Na-alkaline series) from Pantelleria Island (Sicilian Channel). Although some lava millstones from other volcanic regions are recorded, the above four Italian volcanic rock types represent the most exploited in antiquity. A comparison between volcanic millstones and outcropping lavas already exists, from literature data, through thin section modal mineralogy and conventional igneous petrology (i.e., TAS classification, magmatic affinities, and major-trace elements signature). Therefore, on this basis we propose a set of discriminating geochemical parameters (major-trace elements and element ratios diagrams) useful for a quick assessment tool to possibly evaluate one of these four exploited volcanic areas of Italy matching millstones. A sketch of volcanic millstone trade networks and commercial routes in antiquity throughout the Central-Western Mediterranean has been also reported and overviewed on the basis of the literature data.

Quantitative Geochemical Prediction from Spectral Measurements and its Application to Spatially Dispersed Spectral Data

The efficacy of predicting geochemical parameters with a 2-chain workflow using spectral data as the initial input is evaluated. Spectral measurements spanning the approximate 400-25000nm spectral range are used to train a workflow consisting of a non-negative matrix function (NMF) step, for data reduction, and a random forest regression (RFR) to predict 8 geochemical parameters. Approximately 175000 spectra with their corresponding chemical analysis were available for training, testing and validation purposes. The samples and their spectral and chemical parameters represent 9399 drillcore. Of those, approximately 20000 spectra and their accompanying analysis were used for training and 5000 for model validation. The remaining pairwise data (150000 samples) were used for testing of the method. The data are distributed over 2 large spatial extents (980 km2 and 3025 km2 respectively) and allowed the proposed method to be tested against samples that are spatially distant from the initial training points. Global R2 scores and wt.% RMSE on the 150000 validation samples are Fe(0.95/3.01), SiO2(0.96/3.77), Al2O3(0.92/1.27), TiO(0.68/0.13), CaO(0.89/0.41), MgO(0.87/0.35), K2O(0.65/0.21) and LOI(0.90/1.14), given as Parameter(R2/RMSE), and demonstrate that the proposed method is capable of predicting the 8 parameters and is stable enough, in the environment tested, to extend beyond the training sets initial spatial location.

Polyformational Agdai Massif (Verkhoyansk-Kolyma Orogenic Region)

The earliest Mesozoic granitoid formations of the Verkhoyansk-Kolyma orogenic region are derivatives of the Late Jurassic-Early Cretaceous gabbro-diorite-granodiorite formation, involvinggold and polymetallic mineralization. Late Cretaceous alkaline-feldspar or alkaline granites with associated rare-earth mineralization complete the granitoid magmatism of the region. The Agdai massif, which combines both of the mentioned groups of rocks, was the object of our research. Therefore, understanding their petrological and genetic features is of great interest. It is determined that the eastern part of the massif is composed of diorites and granodiorites and includes autoliths and xenoliths of gabbro-diorite composition. The isotopic K-Ar age of gabbro-diorites is 154Ma, diorites –148 Ma, granodiorites –117–124 Ma, and dike granites – 114 Ma. The rocks are characterized bydisequilibrium mineral assemblages: early magmatic pyroxene-Labrador, typical for the basic rocks, and late - micropegmatite granitoid. The origin of the parent melts occurred within the lower crust in amphibolite substrates at temperatures of 1000–1150°C and a pressure of 1.4-1.6 GPa under the influence of the mantle main melt and the partial mixing of the latter with the resulting crustal melt. The western part of the outcrop was formed at the beginning of the Late Cretaceous (the isotopic K-Ar age of the granites is 92+/-3 Ma) and is composed of alkaline feldspar leucogranites. According to all petro - and geochemical parameters, the rocks are defined as post-orogenic or rift-related granites of the A-type. The presence of inclusions of pyroxene-labrador composition, titanomagnetite, zircon of morphotype D and the ratio of the basic petrochemical parameters allow us to refer them to A-type granites related to continental rifting. High melt temperatures (990-1030°C) at relatively low pressures during magma generation (0.7–0.8 GPa) could be achieved only when additional heat was supplied from an external (deep) source. The presence of nonequilibrium mineral associations indicates a possible syntax of the granite and the main melt. In general, the Agdai massif is a polyformational, polygenic structure formed by the intrusion of melts through common or closely located magma conduits.