Coning Control and Recovery Improvement Using In-Situ Water Drainage/Injection in Bottom/Water/Drive Reservoir

2010 ◽  
Author(s):  
Lu Jin ◽  
Andrew Krzysztof Wojtanowicz
Keyword(s):  
Bottom Water ◽  
Water Drainage

In situ electrokinetic isolation of cadmium from paddy soil through pore water drainage: Effects of voltage gradient and soil moisture

2018 ◽  
Vol 337 ◽  
pp. 210-219 ◽  
Author(s):  
Xianqiang Tang ◽  
Qingyun Li ◽  
Zhenhua Wang ◽  
Yanping Hu ◽  
Yuan Hu ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Pore Water ◽  
Paddy Soil ◽  
Voltage Gradient ◽  
Water Drainage

scholarly journals Parameterization of biogeochemical sediment–water fluxes using in situ measurements and a diagenetic model

2016 ◽  
Vol 13 (1) ◽  
pp. 77-94 ◽  
Author(s):  
A. Laurent ◽  
K. Fennel ◽  
R. Wilson ◽  
J. Lehrter ◽  
R. Devereux
Keyword(s):  
Water Column ◽  
Bottom Water ◽  
In Situ Measurements ◽  
Nutrient Loads ◽  
Water Fluxes ◽  
Overlying Water ◽  
Louisiana Shelf ◽  
Biogeochemical Models ◽  
Bottom Waters

Abstract. Diagenetic processes are important drivers of water column biogeochemistry in coastal areas. For example, sediment oxygen consumption can be a significant contributor to oxygen depletion in hypoxic systems, and sediment–water nutrient fluxes support primary productivity in the overlying water column. Moreover, nonlinearities develop between bottom water conditions and sediment–water fluxes due to loss of oxygen-dependent processes in the sediment as oxygen becomes depleted in bottom waters. Yet, sediment–water fluxes of chemical species are often parameterized crudely in coupled physical–biogeochemical models, using simple linear parameterizations that are only poorly constrained by observations. Diagenetic models that represent sediment biogeochemistry are available, but rarely are coupled to water column biogeochemical models because they are computationally expensive. Here, we apply a method that efficiently parameterizes sediment–water fluxes of oxygen, nitrate and ammonium by combining in situ measurements, a diagenetic model and a parameter optimization method. As a proof of concept, we apply this method to the Louisiana Shelf where high primary production, stimulated by excessive nutrient loads from the Mississippi–Atchafalaya River system, promotes the development of hypoxic bottom waters in summer. The parameterized sediment–water fluxes represent nonlinear feedbacks between water column and sediment processes at low bottom water oxygen concentrations, which may persist for long periods (weeks to months) in hypoxic systems such as the Louisiana Shelf. This method can be applied to other systems and is particularly relevant for shallow coastal and estuarine waters where the interaction between sediment and water column is strong and hypoxia is prone to occur due to land-based nutrient loads.

scholarly journals Characteristics of the Exchange Flow of the Bay of Quinte and Its Sheltered Embayments with Lake Ontario

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1857
Author(s):  
Jennifer A. Shore
Keyword(s):  
Bottom Water ◽  
Late Summer ◽  
Lake Ontario ◽  
Exchange Flow ◽  
3 Dimensional ◽  
Flushing Rate ◽  
Algae Growth ◽  
In Situ Observations ◽  
Water Speed

The nature of the exchange flow between the Bay of Quinte and Lake Ontario has been studied to illustrate the effects of the seasonal onset of stratification on the flushing and transport of material within the bay. Flushing is an important physical process in bays used as drinking water sources because it affects phosphorous loads and water quality. A 2-d analytical model and a 3-dimensional numerical coastal model (FVCOM) were used together with in situ observations of temperature and water speed to illustrate the two-layer nature of the late summer exchange flow between the Bay of Quinte and Lake Ontario. Observations and model simulations were performed for spring and summer of 2018 and showed a cool wedge of bottom water in late summer extending from Lake Ontario and moving into Hay Bay at approximately 3 cm/s. Observed and modelled water speeds were used to calculate monthly averaged fluxes out of the Bay of Quinte. After the thermocline developed, Lake Ontario water backflowed into the Bay of Quinte at a rate approximately equal to the surface outflow decreasing the flushing rate. Over approximately 18.5 days of July 2018, the winds were insufficiently strong to break down the stratification, indicating that deeper waters of the bay are not well mixed. Particle tracking was used to illustrate how Hay Bay provides a habitat for algae growth within the bay.

scholarly journals In situ measurements of thermal diffusivity in sediments of the methane-rich zone of Cascadia Margin, NE Pacific Ocean

Elem Sci Anth ◽  
2015 ◽  
Vol 3 ◽  
Author(s):  
Kira Homola ◽  
H. Paul Johnson ◽  
Casey Hearn
Keyword(s):  
Thermal Diffusivity ◽  
Pacific Ocean ◽  
Methane Hydrate ◽  
Bottom Water ◽  
Global Scale ◽  
In Situ Measurements ◽  
Bottom Water Temperature ◽  
Cascadia Margin ◽  
Ne Pacific

Abstract Thermal diffusivity (TD) is a measure of the temperature response of a material to external thermal forcing. In this study, TD values for marine sediments were determined in situ at two locations on the Cascadia Margin using an instrumented sediment probe deployed by a remotely operated vehicle. TD measurements in this area of the NE Pacific Ocean are important for characterizing the upslope edge of the methane hydrate stability zone, which is the climate-sensitive boundary of a global-scale carbon reservoir. The probe was deployed on the Cascadia Margin at water depths of 552 and 1049 m for a total of 6 days at each site. The instrumented probe consisted of four thermistors aligned vertically, one sensor exposed to the bottom water and one each at 5, 10, and 15 cm within the sediment. Results from each deployment were analyzed using a thermal conduction model applying a range of TD values to obtain the best fit with the experimental data. TD values corresponding to the lowest standard deviations from the numerical model runs were selected as the best approximations. Overall TDs of Cascadia Margin sediments of 4.33 and 1.15 × 10–7 m2 s–1 were calculated for the two deployments. These values, the first of their kind to be determined from in situ measurements on a methane hydrate-rich continental margin, are expected to be useful in the development of models of bottom-water temperature increases and their implications on a global scale.

Assessment of Down-Hole Water Sink Technology for Controlling Water Inflow at Petroleum Wells

2004 ◽  
Vol 126 (4) ◽  
pp. 334-341 ◽  
Author(s):  
Andrew K. Wojtanowicz ◽  
Miguel Armenta
Keyword(s):  
Bottom Water ◽  
Water Inflow ◽  
Water Drainage ◽  
Gas Reservoirs ◽  
Water Contact ◽  
Hydrocarbon Production ◽  
Well Completion ◽  
Oil Water ◽  
Petroleum Wells ◽  
Downhole Water Sink

Water inflow to petroleum wells hampers production of oil or gas leading to early shut downs of the wells without sufficient recovery of hydrocarbons in place. Downhole water sink (DWS) is a completion/production technique for producing water-free hydrocarbons with minimum amount of water from reservoirs with bottom water drive and strong tendency to water coning. DWS eliminates water invasion to hydrocarbon production by employing hydrodynamic mechanism of coning control in situ at the oil-water or gas-water contact. The mechanism is based upon a localized water drainage generated by another well completion (downhole water sink) installed in the aquifer beneath the oil/water or gas/water contact. The paper summarizes the development and state-of-the-art of DWS technology. Presented are results from theoretical studies, physical and numerical experiments, and field projects to date. It is demonstrated that DWS could increase recovery and control water production in vertical and horizontal oil wells—with natural flow, downhole pumps or gas lift, and in the gas wells producing from low-pressure tight gas reservoirs. To date, DWS has been used in reservoirs with bottom water. Moreover, in principle, the technology might also be used in the dipping reservoir structures with encroaching side-water.

scholarly journals Microbial Manganese and Sulfate Reduction in Black Sea Shelf Sediments

2000 ◽  
Vol 66 (7) ◽  
pp. 2888-2897 ◽  
Author(s):  
Bo Thamdrup ◽  
Ram�n Rossell�-Mora ◽  
Rudolf Amann
Keyword(s):  
Black Sea ◽  
Bottom Water ◽  
Most Probable Number ◽  
Probable Number ◽  
Manganese Reduction ◽  
Oxidation Rates ◽  
Mn Oxide ◽  
Shelf Sediments ◽  
Reducing Bacteria

ABSTRACT The microbial ecology of anaerobic carbon oxidation processes was investigated in Black Sea shelf sediments from mid-shelf with well-oxygenated bottom water to the oxic-anoxic chemocline at the shelf-break. At all stations, organic carbon (Corg) oxidation rates were rapidly attenuated with depth in anoxically incubated sediment. Dissimilatory Mn reduction was the most important terminal electron-accepting process in the active surface layer to a depth of ∼1 cm, while SO4 2− reduction accounted for the entire Corg oxidation below. Manganese reduction was supported by moderately high Mn oxide concentrations. A contribution from microbial Fe reduction could not be discerned, and the process was not stimulated by addition of ferrihydrite. Manganese reduction resulted in carbonate precipitation, which complicated the quantification of Corg oxidation rates. The relative contribution of Mn reduction to Corg oxidation in the anaerobic incubations was 25 to 73% at the stations with oxic bottom water. In situ, where Mn reduction must compete with oxygen respiration, the contribution of the process will vary in response to fluctuations in bottom water oxygen concentrations. Total bacterial numbers as well as the detection frequency of bacteria with fluorescent in situ hybridization scaled to the mineralization rates. Most-probable-number enumerations yielded up to 105 cells of acetate-oxidizing Mn-reducing bacteria (MnRB) cm−3, while counts of Fe reducers were <102 cm−3. At two stations, organisms affiliated with Arcobacter were the only types identified from 16S rRNA clone libraries from the highest positive MPN dilutions for MnRB. At the third station, a clone type affiliated with Pelobacter was also observed. Our results delineate a niche for dissimilatory Mn-reducing bacteria in sediments with Mn oxide concentrations greater than ∼10 μmol cm−3 and indicate that bacteria that are specialized in Mn reduction, rather than known Mn and Fe reducers, are important in this niche.

scholarly journals Phosphorus recycling in sediments of the Central Baltic Sea

2012 ◽  
Vol 9 (11) ◽  
pp. 15459-15500
Author(s):  
L. Viktorsson ◽  
N. Ekeroth ◽  
M. Nilsson ◽  
M. Kononets ◽  
P. O. J. Hall
Keyword(s):  
Baltic Sea ◽  
Bottom Water ◽  
Dissolved Inorganic Carbon ◽  
Flux Ratio ◽  
Ex Situ ◽  
Data Set ◽  
C:P Ratio ◽  
Baltic Proper ◽  
The Baltic

Abstract. Benthic fluxes of dissolved inorganic phosphorus (DIP) were measured in situ in the Eastern Gotland Basin (EGB), Central Baltic Sea, using benthic landers. A total of 40 flux measurements on 13 stations at water depths ranging from 30–210 m and under different oxygen regimes were carried out on three cruises during three consecutive years (2008–2010) in August–September. Our study is the first to report in situ DIP fluxes in the Baltic Proper, and it provides the most comprehensive data set of benthic DIP fluxes in the Baltic Proper existing to date. DIP fluxes increased with increasing water depth and with decreasing bottom water oxygen concentration. Average fluxes were calculated for oxic bottom water conditions (−0.003 ± 0.040 mmol m−2 d−1), hypoxic conditions (0.027 ± 0.067 mmol m−2 d−1) and anoxic conditions (0.376 ± 0.214 mmol m−2 d−1). The mean flux on anoxic bottoms was ca. 5–10 times higher than previous estimates based on ex situ measurements, but agreed well with previous flux estimations from changes in the basin water DIP pool. The DIP flux was positively correlated with the organic carbon inventory of sediment and the benthic flux of dissolved inorganic carbon (DIC) on anoxic stations, but these variables were uncorrelated on oxic stations. The positive correlation between DIP and DIC fluxes suggests that the benthic DIP flux on anoxic bottoms in the Baltic Proper is mainly controlled by rates of deposition and degradation of organic matter. The flux from anoxic sediment was very P rich in relation to both C and N, and the average C:P ratio in fluxes on anoxic accumulation bottoms was 69 ± 15, which is well below the Redfield C:P ratio of 106:1. On oxic stations, however, the C:P flux ratio was much higher than the Redfield ratio, consistent with well-known P retention mechanisms associated with iron and bacteria in oxidized sediment. Using a benthic mass balance approach, a burial efficiency of 4% was calculated for the anoxic part of the EGB, which suggests that anoxic Baltic sediments are very efficient in recycling deposited P. Based on the measured fluxes and recent estimates of the areal extent of anoxic and hypoxic bottoms, an internal load of 146 kton yr−1 was calculated. This is 7–12 times higher than recent estimates of the external load and clearly highlights the dominance of anoxic sediments as a P source in the Baltic Sea.

Sign in / Sign up

Export Citation Format

Share Document