Submarine Environment Research Articles

Geochemical constraints on the genesis of the Algoma-type banded iron formation (BIF) in Yishui County, western Shandong Province, North China Craton

The Yishui iron deposit is a typical Algoma-type banded iron formation (BIF) located in Yishui County, Taishan Group, Shandong Province in the Eastern Block (EB) of the North China Craton (NCC). The BIF is interlayered with amphibolite, migmatitic granite, gneiss, and schist. Integrated petrological, mineralogical, and geochemical interpretations of the iron ores were used to reconstruct the genesis of the Yishui BIFs and their tectonic evolution. The iron ore samples were collected from surface outcrops. Banding textures are not always present in the iron ores because the BIF experienced complex high-grade metamorphism after precipitation. Interpretations of the major elements and rare earth elements plus yttrium (REY) data of the iron ores suggests that the ore-forming materials of the Yishui BIF precipitated from a mixture of seawater and high-temperature hydrothermal fluids (<0.1%) in a submarine environment with volcanic activity under relatively low oxygen conditions. Large amounts of iron and silica were produced under these conditions. The main compositions of SiO2 and Fe2O3T (SiO2+Fe2O3T=85.8–95.8wt%) are consistent with the major minerals, such as quartz and iron oxide, which represent chemical precipitates. Chlorite, amphibole, plagioclase, biotite, and calcite are present as minor minerals. The low contents of TiO2 (0.01–0.09wt%), Al2O3 (0.42–1.18wt%), and high field strength elements (HFSEs) indicate little to no detrital assimilation, which implies that the iron ores preserved their original geochemical signatures. Based on geochemical interpretations, we conclude that the Yishui BIF can be explained by a mantle plume model that describes not only the tectonic evolution but also the sources of iron and silica of the Yishui BIF.

MINERALOGICAL CONTRAINTS TO THE FORMATION OF VEIN-TYPE ZEOLITES FROM KIZARI AREA, THRACE NORTHERN GREECE

Vein-type zeolites in Kizari area, (western Thrace) are found within fresh to zeolitic altered volcanic rocks of andesitic to dacitic composition. The zeolites stilbite-Ca, Sr-bearing heulandite-Ca and laumontite occur in epithermal-style crustiform quartz/chalcedony-calcite veins crosscuting lavas and volcanic breccias. Open-space filling is common and well-shaped crystals (up to 3cm) were observed. Smectite, feldspar, magnetite, pyrite and rutile occur in minor amounts in the veins. Halite and barite grains are included in stilbite-Ca. SEM EDS data indicate high Sr (up to 4.4 wt. % SrO) and Ba (up to 2.9 wt. % BaO) contents for heulandite-Ca. It is suggested that the studied zeolites are intergral parts of the porphyry-epithermal mineralizing systems which operated in the area during the Oligocene. Their formation took place in the outmost transitional propylitic to fresh zones of the porphyry-epithermal systems and in a submarine environment as indicated by the geological and mineralogical evidence.

Effect of water activity on rates of serpentinization of olivine

The hydrothermal alteration of mantle rocks (referred to as serpentinization) occurs in submarine environments extending from mid-ocean ridges to subduction zones. Serpentinization affects the physical and chemical properties of oceanic lithosphere, represents one of the major mechanisms driving mass exchange between the mantle and the Earth’s surface, and is central to current origin of life hypotheses as well as the search for microbial life on the icy moons of Jupiter and Saturn. In spite of increasing interest in the serpentinization process by researchers in diverse fields, the rates of serpentinization and the controlling factors are poorly understood. Here we use a novel in situ experimental method involving olivine micro-reactors and show that the rate of serpentinization is strongly controlled by the salinity (water activity) of the reacting fluid and demonstrate that the rate of serpentinization of olivine slows down as salinity increases and H2O activity decreases.

Neoarchean Algoma-type banded iron formation from the Northern Shanxi, the Trans-North China Orogen: SIMS U-Pb age, origin and tectonic setting

Algoma-type BIF-hosted iron deposits in Northern Shanxi occur in Sanyangping, Baiyuli, Zhaocun and Baizhiyan. These deposits are developed in Archaean rocks and their formation was related to volcanic and sedimentary processes in small volcano-sedimentary basins. Supracrustal rocks of the Wutai Group were metamorphosed from greenschist facies to lower amphibolite facies. The BIF-hosted iron deposit in Northern Shanxi formed in the late Neoarchean, and is represented by the Zhaocun deposit that yielded a SIMS U-Pb zircon age of 2693.7±4.9Ma. The other two BIF-hosted iron deposits are represented by the Sanyangping and Baiyuli deposits that formed between 2528Ma and 2543Ma. The late Neoarchean BIF iron deposits can be considered to have formed in a magmatic arc environment. The Eu anomalies of the ore samples from Northern Shanxi show that the BIF ores formed in a hydrothermal related volcanic submarine environment, where submarine hydrothermal effluents associated with volcanic activities may have supplied the iron and silica for the Northern Shanxi BIFs. A ridge subduction model is suggested for the formation of the BIFs and their host late Neoarchean volcanic rocks, this model does not only explain the sources of silica and iron for the BIFs, but can also well explain many other geological features of the Trans-North China Orogen.

Hydrothermally altered volcanic rocks metamorphosed at granulite-facies conditions: an example from the Grenville Province

A 1.2 Ga association of aluminous gneisses, garnetites, and white felsic gneisses of andesitic composition in the southern Manicouagan area (central Grenville Province) provides evidence consistent with protolith formation and hydrothermal alteration in a submarine volcanic environment. In addition to field relations, potential relics of quartz phenocrysts in the aluminous gneisses, revealed by SEM–MLA (scanning electron microscope with a mineral liberation analysis software) imaging, are consistent with a volcanic precursor. Moreover, in these rocks, aluminous nodules and seams of sillimanite are considered to represent metamorphosed hydrothermal mineral assemblages and to reflect former pathways of hydrothermal fluid. These features are preserved despite the Grenvillian granulite-facies metamorphic overprint and evidence of partial melting. In addition, the garnetites are inferred to represent hydrothermally altered products of the white gneisses, based on the gradational contacts between the two rock types. The compositional ranges of minerals are generally similar to those of granulite-facies metapelites, but moderately elevated contents of Mn in garnet from the garnetites, and Zn in spinel from the aluminous gneisses, are consistent with hydrothermal addition of these elements to the protolith. The most prominent alteration trends are an increase in Fe–Mg–Mn from the white gneisses to the aluminous gneisses and the garnetites, and a trend of increasing alumina index in some white gneisses, suggesting mild argillic alteration. The new findings highlight the preservation of early hydrothermal alteration in high-grade metamorphic belts in the Grenville Province, and these altered rocks are potential targets for exploration.

Submarine landside in the Bussol Graben: Structural and formation features

Analysis of geophysical data obtained during a study of the insular slope in the central Kuril‒Kamchatka Trench during projects Kuriles-2005 and Kuriles-2006 promoted by the Presidium of the Russian Academy of Sciences revealed a large submarine landslide in this area. The landslide, located at the bottom of the transverse valley confined to the Bussol l Graben, resulted from the failure of the northeastern wall of a graben composed of sedimentary material. It exceeds 35 km3 in size, representing one of the large submarine landslides discovered to date on the slope of the Kuril‒Kamchatka Trench in submarine canyonfan environments.

Shallow submarine barite mineralisation on Milos Island, Greece

Recently emerged volcanoes and associated epithermal systems provide a geologically young and accessible laboratory to study volcanic-hydrothermal systems from the shallow submarine environment (Na...

In situ Raman spectroscopic study of the pressure effect on the concentration of CO2 in water at hydrate-liquid water equilibrium up to 900 bar

CO2 hydrate may form during the injection of CO2 into the submarine environment for CO2 storage or enhanced recovery of CH4 hydrate. The growth of CO2 hydrate in seawater is dependent on the concentration of CO2 in seawater in equilibrium with hydrate. However, such data are currently only available at pressures below 250 bar, and the pressure effect on the concentration of CO2 in water at hydrate-liquid water equilibrium still remains controversial. In this study, Raman spectroscopy was applied to measure the concentration of CO2 in water in equilibrium with hydrate from 276.15 to 289.05 K and from 30 to 900 bar. Our results show that the concentration of CO2 in water at hydrate-liquid water equilibrium increases with increasing temperature (∼0.081 mol/(kg K) on average), but decreases slightly with increasing pressure (−0.016, −0.021 and −0.034 mol/(kg·100 bar) at 276.15, 280.15 and 285.15 K, respectively). An equation that can well reproduce the current and previous measurements of CO2 concentration in water at hydrate-liquid water equilibrium was proposed.

Адаптация геологических построений к данным сейсморазведки на примере глубоководных отложений, осложненных оползневыми процессами

Адаптация геологических построений к данным сейсморазведки на примере глубоководных отложений, осложненных оползневыми процессами

Greater contrast in Martian hydrological history from more accurate estimates of paleodischarge

AbstractCorrelative width‐discharge relationships from the Missouri River Basin are commonly used to estimate fluvial paleodischarge on Mars. However, hydraulic geometry provides alternative, and causal, width‐discharge relationships derived from broader samples of channels, including those in reduced‐gravity (submarine) environments. Comparison of these relationships implies that causal relationships from hydraulic geometry should yield more accurate and more precise discharge estimates. Our remote analysis of a Martian‐terrestrial analog channel, combined with in situ discharge data, substantiates this implication. Applied to Martian features, these results imply that paleodischarges of interior channels of Noachian‐Hesperian (~3.7 Ga) valley networks have been underestimated by a factor of several, whereas paleodischarges for smaller fluvial deposits of the Late Hesperian‐Early Amazonian (~3.0 Ga) have been overestimated. Thus, these new paleodischarges significantly magnify the contrast between early and late Martian hydrologic activity. Width‐discharge relationships from hydraulic geometry represent validated tools for quantifying fluvial input near candidate landing sites of upcoming missions.

Development Study of an Air Independent Fuel Cell System for an Autonomous Underwater Vehicle (AUV)

In this work a design process for the development of an air independent fuel cell system operating a commercial fuel cell stack as a range extender in an AUV is presented. The development follows an optimization strategy which has been derived from the universal fuel cell development plan proposed by Ang et al.[1] The first step is defining the constraints and the objectives in the design process. While constraints set the boundary conditions of the system the identified objectives are used as optimization parameters. The design plan follows the schematic in figure1: Figure 1: design concept for an optimized system used in an AUV The development of fuel cell systems used in a submarine environment will need to consider different boundary conditions than the development of a fuel cell system for automobiles. These constraints result from the sea water environment which can’t be used as an oxygen source and additionally hinders mass exchange with the fuel cell system because of pressure differences. As a result a closed fuel cell system relying on a pure oxygen supply has to be developed. The fuel cell is powering the AUV with a stationary output while a battery is buffering the power differential between the output und the consumption of the AUV. The AUV is used as a testing platform by the German navy and thereby sets very unique constraints on the system development. Additionally the commercial fuel cell stack is setting boundary conditions for the system development, which has to meet the stacks individual operating conditions. After identifying the boundary conditions the system size was identified as the optimization parameter. To optimize the system size different setups for the cooling system as well as the gas supply system found in the literature are evaluated. Setups meeting the boundary conditions are validated in a test bench with hardware-in-the-loop tests. Based on these measurements a volume-optimized system can be found. Challenges which deviate from this setup are identified and can be tackled in the subsequent design step. The next step is a discussion of the different concepts and an evaluation of their impact on the system operation. While the discussed solutions are still meeting the maximum system size, an evaluation of their influence on other design parameters can be made. From this different system designs are derived and the resulting operation strategies are compared to further improve the volume-optimized system. Also solutions targeting specific challenges like standby mode and system shutdown are evaluated and presented. In a last step the qualitative connections between the found system designs and the boundary conditions in this system are discussed leading to a more general approach for the development of air independent fuel cell systems for AUVs. [1] S. M. C. Ang, E. S. Fraga, N. P. Brandon, N. J. Samsatli, and D. J. L. Brett, “Fuel cell systems optimisation – Methods and strategies,” Int. J. Hydrogen Energy, vol. 36, no. 22, pp. 14678–14703, Nov. 2011. Figure 1

Metagenomic and PCR-Based Diversity Surveys of [FeFe]-Hydrogenases Combined with Isolation of Alkaliphilic Hydrogen-Producing Bacteria from the Serpentinite-Hosted Prony Hydrothermal Field, New Caledonia.

High amounts of hydrogen are emitted in the serpentinite-hosted hydrothermal field of the Prony Bay (PHF, New Caledonia), where high-pH (~11), low-temperature (< 40°C), and low-salinity fluids are discharged in both intertidal and shallow submarine environments. In this study, we investigated the diversity and distribution of potentially hydrogen-producing bacteria in Prony hyperalkaline springs by using metagenomic analyses and different PCR-amplified DNA sequencing methods. The retrieved sequences of hydA genes, encoding the catalytic subunit of [FeFe]-hydrogenases and, used as a molecular marker of hydrogen-producing bacteria, were mainly related to those of Firmicutes and clustered into two distinct groups depending on sampling locations. Intertidal samples were dominated by new hydA sequences related to uncultured Firmicutes retrieved from paddy soils, while submarine samples were dominated by diverse hydA sequences affiliated with anaerobic and/or thermophilic submarine Firmicutes pertaining to the orders Thermoanaerobacterales or Clostridiales. The novelty and diversity of these [FeFe]-hydrogenases may reflect the unique environmental conditions prevailing in the PHF (i.e., high-pH, low-salt, mesothermic fluids). In addition, novel alkaliphilic hydrogen-producing Firmicutes (Clostridiales and Bacillales) were successfully isolated from both intertidal and submarine PHF chimney samples. Both molecular and cultivation-based data demonstrated the ability of Firmicutes originating from serpentinite-hosted environments to produce hydrogen by fermentation, potentially contributing to the molecular hydrogen balance in situ.

Underwater image processing method for fish localization and detection in submarine environment

Object detection is an important process in image processing, it aims to detect instances of semantic objects of a certain class in digital images and videos. Object detection has applications in many areas of computer vision such as underwater fish detection. In this paper we present a method for preprocessing and fish localization in underwater images. We are based on a Poisson–Gauss theory, because it can accurately describe the noise present in a large variety of imaging systems. In the preprocessing step we denoise and restore the raw images. These images are split into regions utilizing the mean shift algorithm. For each region, statistical estimation is done independently in order to combine regions into objects. The method is tested under different underwater conditions. Experimental results show that the proposed approach outperforms state of the art methods.

Concentration of hydroxyl defects in quartz from various rhyolitic ignimbrite horizons: results from unpolarized micro-FTIR analyses on unoriented phenocryst fragments

Hydroxyl defect concentrations of quartz phenocryst fragments from various rhyolitic pyroclastic density current deposits from the Bukk Foreland Volcanic Area, Hungary, were determined by using micro-FTIR spectrometry. In addition trace-element analysis and SEM cathodoluminescence imaging were performed on the same crystals. Hydroxyl defect-content (expressed in water equivalent) of volcanic quartz ranges from 0.9±0.1 to 2.8±0.4 wt. ppm, which is lower than those in quartz of plutonic (granitic), metamorphic and hydrothermal origin. The incorporation of hydroxyl defect is mainly due to H+ + Al3+ substitutions into Si-tetrahedral vacancies of quartz. Furthermore, the presence of molecular water probably in (nano-)inclusions was proven. The post-eruptive diffusive loss of hydroxyl defects during cooling seems to be the main factor causing the very low concentration of hydroxyl defects. This may be also manifested in the almost homogeneous distribution of hydroxyl defects regardless of the considerable zonation in Al-content, although complete diffusive loss of hydroxyl defects was possibly hindered by the cooling effect of phreatomagmatism (interaction of excess water with magma during eruption) and deposition in a shallow submarine environment. Moreover, a reasonable linear correlation is observed between the integrated area of Si–O bands (between 2110 and 1440 cm−1) and sample thickness up to ~300 μm by studying unoriented quartz phenocryst fragments. This may enable the quantitative analysis of hydroxyl defects in separated quartz crystals without the need for preparing oriented thin sections.

Raman spectra of Martian glass analogues: A tool to approximate their chemical composition.

Raman spectrometers will form a key component of the analytical suite of future planetary rovers intended to investigate geological processes on Mars. In order to expand the applicability of these spectrometers and use them as analytical tools for the investigation of silicate glasses, a database correlating Raman spectra to glass composition is crucial. Here we investigate the effect of the chemical composition of reduced silicate glasses on their Raman spectra. A range of compositions was generated in a diffusion experiment between two distinct, iron‐rich end‐members (a basalt and a peralkaline rhyolite), which are representative of the anticipated compositions of Martian rocks. Our results show that for silica‐poor (depolymerized) compositions the band intensity increases dramatically in the regions between 550–780 cm−1 and 820–980 cm−1. On the other hand, Raman spectra regions between 250–550 cm−1 and 1000–1250 cm−1 are well developed in silica‐rich (highly polymerized) systems. Further, spectral intensity increases at ~965 cm−1 related to the high iron content of these glasses (~7–17 wt % of FeOtot). Based on the acquired Raman spectra and an ideal mixing equation between the two end‐members we present an empirical parameterization that enables the estimation of the chemical compositions of silicate glasses within this range. The model is validated using external samples for which chemical composition and Raman spectra were characterized independently. Applications of this model range from microanalysis of dry and hydrous silicate glasses (e.g., melt inclusions) to in situ field investigations and studies under extreme conditions such as extraterrestrial (i.e., Mars) and submarine volcanic environments.

Chloritites of the Tocantins Group, Araguaia fold belt, central-northern Brazil: Vestiges of basaltic magmatism and metallogenetic implications

Chloritites from different localities (Arapoema, Couto Magalhães Velho, Juarina, Morro Grande, Morro do Jabuti, Morro do Pau Ferrado, Morro do Salto, Serra do Jacu, Serra do Quatipuru, Serra do Tapa, Serrinha) of the Araguaia fold belt, Tocantins geotectonic province, central-northern Brazil, have been investigated. Based on field work and petrographic, diffractometric, geochemical and mineral chemistry data, these rocks, commonly associated with metacherts and banded iron formations, have been interpreted as products of ocean-floor exhalative-hydrothermal activity on MORB basalts. Distribution patterns of rare earth elements and diagrams of relatively immobile components in the hydrothermal environment highlight not only the genetic link between the chloritites and the basaltic rocks that occur in the region (Serra do Tapa and Morro do Agostinho), but also some peculiar characteristics of the submarine environment. The rock association and anomalous contents of Cu, Zn, Ni, As, and Au are suggestive that the region was favorable to the formation of volcanogenic massive sulfide deposits, what makes it a potential target for mineral exploration programs.

Models for the estimation of Fe3+/Fetotratio in terrestrial and extraterrestrial alkali- and iron-rich silicate glasses using Raman spectroscopyk

To develop Raman spectroscopy as a quantitative tool in both geosciences and planetary sciences the effect of iron oxidation state (Fe 3+ /Fe tot ) on the Raman spectra of basaltic and pantelleritic glasses has been investigated. We have used remelted pantellerite from Pantelleria Island and synthetic iron-rich basaltic glasses [from Chevrel et al. (2014)]. The Raman spectra of pantelleritic glasses reveal dramatic changes in the high wavelength region of the spectrum (800–1200 cm −1 ) as iron oxidation state changes. In particular the 970 cm −1 band intensity increases with increasing oxidation state of the glass (Fe 3+ /Fe tot ratio from 0.24 to 0.83). In contrast, Raman spectra of the basaltic glasses do not show the same oxidation state sensitivity (Fe 3+ /Fe tot ratio from 0.15 to 0.79). A shift, however, of the 950 cm −1 band to high wavenumber with decreasing iron oxidation state can be observed. We present here two empirical parameterizations (for silica- and alkali-rich pantelleritic glasses and for iron-rich basaltic glasses) to enable estimation of the iron oxidation state of both anhydrous and hydrous silicate glasses (up to 2.4 wt% H 2 O). The validation of the models derived from these parameterizations have been obtained using the independent characterization of these melt samples plus a series of external samples via wet chemistry. The “pantelleritic” model can be applied within SiO 2 , FeO, and alkali content ranges of ~69–75, ~7–9, and ~8–11 wt%, respectively. The “basaltic” model is valid within SiO 2 , FeO, and alkali content ranges of ~42–54, ~10–22, and ~3–6 wt%, respectively. The results of this study contribute to the expansion of the compositionally dependent database previously presented by Di Genova et al. (2015) for Raman spectra of complex silicate glasses. The applications of these models range from microanalysis of silicate glasses (e.g., melt inclusions) to handheld in situ terrestrial field investigations and studies under extreme conditions such as extraterrestrial (i.e., Mars), volcanic, and submarine environments.

The degradation potential of PET bottles in the marine environment: An ATR-FTIR based approach.

The dominance and persistence of plastic debris in the marine environment are well documented. No information exists in respect to their lifespan in the marine environment. Nevertheless, the degradation potential of plastic litter items remains a critical issue for marine litter research. In the present study, polyethylene terephthalate bottles (PETs) collected from the submarine environment were characterized using ATR-FTIR in respect to their degradation potential attributed to environmental conditions. A temporal indication was used as indicative to the years of presence of the PETs in the environment as debris. PETs seem to remain robust for approximately fifteen years. Afterwards, a significant decrease of the native functional groups was recorded; some even disappear; or new-not typical for PETs-are created. At a later stage, using the PET time series collected from the Saronikos Gulf (Aegean Sea–E. Mediterranean), it was possible to date bottles that were collected from the bottom of the Ionian Sea (W. Greece). It is the first time that such a study has been conducted with samples that were actually degraded in the marine environment.

Hydrothermal zeolitisation controlled by host-rock lithofacies in the Periadriatic (Oligocene) Smrekovec submarine composite stratovolcano, Slovenia

Hydrothermal zeolites (laumontite, yugawaralite, analcime, heulandite, clinoptilolite), prehnite and pumpellyite have been recognised in a succession of volcanic, autoclastic, pyroclastic, resedimented volcaniclastic and mixed siliciclastic–volcaniclastic deposits. In cone-building lithofacies association attaining 310m, the alteration minerals commonly change within a single normally graded depositional unit or alternate in the section on a dm- to m-scale, according to the host-rock lithofacies. Fine-grained deposits rich in juvenile glassy pyroclasts are altered to heulandite and clinoptilolite or analcime, and laumontite widely occurs in coarse-grained host-rocks (lapilli tuff, hyaloclastite breccia, volcaniclastic breccia, hyaloclastites) and fracture systems. In near-vent lithofacies association attaining 420m, prehnite–laumontite, laumontite–analcime, and laumontite–heulandite–clinoptilolite zones developed as a result of superimposed thermal regime generated by the emplacement of an over 200m thick sill.The recognised dependence of alteration on porosity, permeability and fracturing of the host-rock is closely related to hydrological conditions in the stratovolcano-hosted hydrothermal system with convective–advective flow regime. After separation of steam and gases from convecting hydrothermal fluids, denser liquids outflowed intermittently, preferentially through steeply inclined (20–30°) high-permeability layers in the stratovolcano edifice. In low-permeability layers the flow was slow and thermal conditions were mainly attained by conduction. Zeolites developed only in coarse- and fine-grained vitroclastic tuffs, presumably by the dissolution of volcanic glass. The interstratified siliciclastic siltstones, tuffites and resedimented deposits with low content of glassy particles are devoid of zeolites and indicate compositional constraint on zeolitisation.Lava flows, cooling in a submarine environment and undergoing disintegration and mingling with the enclosing water-saturated sediment were individual, ephemeral and spatially localised high-temperature hydrothermal systems favourable for the formation of pumpellyite, prehnite and laumontite.

A Kinematic Approach to Understanding Performance in Upper-Extremity Function during a Goal-Directed Man-Machine Interface Task in a Submariner Environment.

In December of 2014, the United States Congress funded a fundamental shift in the recruiting policy of the US Navy Submarine Force to include the integration of women. As a result, design modifications became necessary, especially those that facilitate integration without inflating costs. Current cost levels associated with new submarine design(s) are maintained through the use of legacy components and systems. Additionally, many of the systems aboard are computer controlled, necessitating man-machine interfaces. As common practice, military activities that involve man-machine interfaces have always focused on the dexterity of the hands, often neglecting the role of movement in the task; therefore, there is a need to understand upper-extremity kinematics issues associated with man-machine interfaces. Joint kinematics of the right upper extremity of 10 subjects was measured using an optoelectronic motion capture system. Center of gravity displacements were measured using a force plate during touchscreen movement tasks paced by six different movement frequencies from a metronome (0, 1.0, 1.3, 1.7, 2.0, and 2.7 Hz). Results showed no significant difference in touch accuracy, task completion time, shoulder and elbow angular displacements, and shoulder and elbow flexion/extension velocity; however, a significant difference (0.002; p ≤ 0.05) in shoulder adduction/abduction velocity was observed. In arranging systems and components in submarine and surface vessel environments, consideration in not only providing a means of adjustability (e.g., height, proximity, and orientation) but in the dimensions of the systems and components themselves must also be considered based on the required operation.