Storage and transport in cave seepage- and groundwater in a South German karst system

Abstract. We investigated one of the best-known and second largest karst areas in Germany (Blautopf Catchment) that offers a unique access waters of the unsaturated zone through a large cave system. As tracers for water flow and storage we measured stable isotopes (18O/16O and D/H ratios) in precipitation, seepage- and groundwater. The precipitation showed a distinct seasonal cycle with δ18O values between −2.6 and −22.6‰ during summer and winter, respectively. However, the isotope signals in seepage water in the caves as well as the discharge were completely buffered and ranged around an average δ18O value of −10‰. This value also matched the long-term average of the precipitation. In addition, the homogeneous isotopic composition of the Blautopf Spring was against expectation for its highly variable discharge (0.3 to 32 m3 s−1) that is typical for a fast responsive karst system. We explain the isotopic similarity between cave seepage and the Blautopf Spring (as an integral signal for groundwater) by nearly complete mixing of the water already in the vadose zone. The latter can be divided into the compartments soil, epikarst and rock matrix that all have good storage capacities and also allow diffusive exchange of solutes between mobile and less mobile matrix water. The above approach revealed new aspects about turnover and flow paths of the infiltrated water and thus helps to constrain the risk by pollution to the groundwater.

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Solute transport processes in a karst vadose zone characterized by long-term tracer tests (the cave system of Postojnska Jama, Slovenia)

Journal of Hydrology ◽

10.1016/j.jhydrol.2014.08.047 ◽

2014 ◽

Vol 519 ◽

pp. 1205-1213 ◽

Cited By ~ 29

Author(s):

Janja Kogovsek ◽

Metka Petric

Keyword(s):

Solute Transport ◽

Vadose Zone ◽

Tracer Tests ◽

Transport Processes ◽

Cave System

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Mixing and transport of water in a karst catchment: a case study from precipitation via seepage to the spring

Hydrology and Earth System Sciences ◽

10.5194/hess-13-285-2009 ◽

2009 ◽

Vol 13 (3) ◽

pp. 285-292 ◽

Cited By ~ 20

Author(s):

K. Schwarz ◽

J. A. C. Barth ◽

C. Postigo-Rebollo ◽

P. Grathwohl

Keyword(s):

Minor Role ◽

Seepage Water ◽

Data Set ◽

Average Value ◽

Cave System ◽

Flow Mixing ◽

Karst Catchment

Abstract. One of the best-known and largest karst areas in Germany, the Blautopf Catchment, offers unique access to waters of the unsaturated zone through a large cave system. It was investigated with stable isotopes (18O/16O and D/H ratios expressed in permille = ‰) in precipitation, seepage- and groundwater as tracers for water flow, mixing, and storage. The precipitation showed a distinct seasonality with δ18O values between −2.9 and −24.6‰ during summer and winter, respectively. However, the isotope signals in seepage water in the caves as well as the discharge were almost completely buffered and ranged around an average δ18O value of −10‰. This value was also close to the long-term average value of local precipitation, −9.3‰. The homogeneous isotopic composition of the Blautopf Spring was unexpected, as its highly variable discharge (0.3 to 32 m3 s−1) is typical for a fast responsive karst system. These isotopic similarities could be explained by nearly complete mixing of the water already in the vadose zone. The data set therefore presents a case study to narrow down zones of mixing in karst catchments. It also confirms the minor role of the fast conduit system in the water balance of the Blautopf Catchment.

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Information technology. Digitally recorded media for information interchange and storage. Test method for the estimation of lifetime of optical disks for long-term data storage

10.3403/30341531u ◽

2017 ◽

Keyword(s):

Information Technology ◽

Data Storage ◽

Test Method ◽

Storage Test ◽

Optical Disks ◽

Information Interchange ◽

And Storage ◽

Term Data

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Information technology. Digitally recorded media for information interchange and storage. Test method for the estimation of lifetime of optical disks for long-term data storage

10.3403/30341531 ◽

2017 ◽

Keyword(s):

Information Technology ◽

Data Storage ◽

Test Method ◽

Storage Test ◽

Optical Disks ◽

Information Interchange ◽

And Storage ◽

Term Data

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MODERN PROBLEMATICS AND ANALYSIS OF EFFICIENCY OF APPLICATION OF DIFFERENT APPROACHES TO DESTRUCTION OF INFORMATION ON MAGNETIC MEDIA

Collection of scientific works of Odesa Military Academy ◽

10.37129/2313-7509.2019.12.2.154-164 ◽

2019 ◽

Vol 2 (12) ◽

pp. 154-164

Author(s):

O. Semenenko ◽

O. Vodchyts ◽

V. Koverga ◽

R. Lukash ◽

O. Lutsenko

Keyword(s):

Armed Forces ◽

Information Storage ◽

Storage Device ◽

Magnetic Media ◽

Long Term Storage ◽

Physical Impact ◽

And Storage ◽

Term Storage

The introduction and active use of information transmission and storage systems in the Ministry of Defense (MoD) of Ukraine form the need to develop ways of guaranteed removal of data from media after their use or long-term storage. Such a task is an essential component of the functioning of any information security system. The article analyzes the problems of guaranteed destruction of information on magnetic media. An overview of approaches to the guaranteed destruction of information on magnetic media of different types is presented, and partial estimates of the effectiveness of their application are given by some generally accepted indicators of performance evaluation. The article also describes the classification of methods of destruction of information depending on the influence on its medium. The results of the analysis revealed the main problems of application of software methods and methods of demagnetization of the information carrier. The issue of guaranteed destruction of information from modern SSD devices, which are actively used in the formation of new systems of information accumulation and processing, became particularly relevant in the article. In today's conditions of development of the Armed Forces of Ukraine, methods of mechanical and thermal destruction are more commonly used today. In the medium term, the vector of the use of information elimination methods will change towards the methods of physical impact by the pulsed magnetic field and the software methods that allow to store the information storage device, but this today requires specialists to develop new ways of protecting information in order to avoid its leakage.

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CHARACTERIZATION OF GROUNDWATER FLOW PATHS THROUGH MEROKARST IN THE N04D SECTION OF THE KONZA PRAIRIE LONG-TERM ECOLOGICAL RESEARCH SITE IN NORTHEASTERN KANSAS, USA

10.1130/abs/2017am-303362 ◽

2017 ◽

Author(s):

Emily R. Barry ◽

◽

G.L. Macpherson

Keyword(s):

Groundwater Flow ◽

Ecological Research ◽

Konza Prairie ◽

Flow Paths ◽

Research Site ◽

Long Term Ecological Research

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Semi-Analytical Solution to Assess CO2 Leakage in the Subsurface through Abandoned Wells

Energies ◽

10.3390/en14092452 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2452

Author(s):

Tian Qiao ◽

Hussein Hoteit ◽

Marwan Fahs

Keyword(s):

Analytical Solution ◽

Storage Site ◽

Co2 Leakage ◽

Transient Pressure ◽

Flow Paths ◽

Abandoned Wells ◽

Diffusivity Equation ◽

Carbon Dioxide Co2 ◽

Good Agreement

Geological carbon storage is an effective method capable of reducing carbon dioxide (CO2) emissions at significant scales. Subsurface reservoirs with sealing caprocks can provide long-term containment for the injected fluid. Nevertheless, CO2 leakage is a major concern. The presence of abandoned wells penetrating the reservoir caprock may cause leakage flow-paths for CO2 to the overburden. Assessment of time-varying leaky wells is a need. In this paper, we propose a new semi-analytical approach based on pressure-transient analysis to model the behavior of CO2 leakage and corresponding pressure distribution within the storage site and the overburden. Current methods assume instantaneous leakage of CO2 occurring with injection, which is not realistic. In this work, we employ the superposition in time and space to solve the diffusivity equation in 2D radial flow to approximate the transient pressure in the reservoirs. Fluid and rock compressibilities are taken into consideration, which allow calculating the breakthrough time and the leakage rate of CO2 to the overburden accurately. We use numerical simulations to verify the proposed time-dependent semi-analytical solution. The results show good agreement in both pressure and leakage rates. Sensitivity analysis is then conducted to assess different CO2 leakage scenarios to the overburden. The developed semi-analytical solution provides a new simple and practical approach to assess the potential of CO2 leakage outside the storage site. This approach is an alternative to numerical methods when detailed simulations are not feasible. Furthermore, the proposed solution can also be used to verify numerical codes, which often exhibit numerical artifacts.

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Quality tracing in meat supply chains

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2013.0308 ◽

2014 ◽

Vol 372 (2017) ◽

pp. 20130308 ◽

Cited By ~ 16

Author(s):

Miriam Mack ◽

Patrick Dittmer ◽

Marius Veigt ◽

Mehmet Kus ◽

Ulfert Nehmiz ◽

...

Keyword(s):

Supply Chains ◽

Process Analysis ◽

Decision Support Tool ◽

Temperature Monitoring ◽

Support Tool ◽

Logistics Network ◽

Primary Model ◽

Sensory Parameters ◽

And Storage

The aim of this study was the development of a quality tracing model for vacuum-packed lamb that is applicable in different meat supply chains. Based on the development of relevant sensory parameters, the predictive model was developed by combining a linear primary model and the Arrhenius model as the secondary model. Then a process analysis was conducted to define general requirements for the implementation of the temperature-based model into a meat supply chain. The required hardware and software for continuous temperature monitoring were developed in order to use the model under practical conditions. Further on a decision support tool was elaborated in order to use the model as an effective tool in combination with the temperature monitoring equipment for the improvement of quality and storage management within the meat logistics network. Over the long term, this overall procedure will support the reduction of food waste and will improve the resources efficiency of food production.

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