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Based on core description, gas logging and laboratory analysis, this paper aims to study the controlling effect of the types of shale sedimentary microfacies in coal formations over shale reservoirs using the example of Shanxi formation in Northern Ordos Basin.

According to core observation, the authors selected typical samples of rock types for thin section analysis to determine the micro features and compositions of rocks.

By using core observation, we found that fine lithology in Shanxi formation included major shale, carbonaceous shale, partially carbonaceous shale, partially silty shale and silty shale with colors of gray, dark gray, black and/or gray. Shanxi Formation shale are deposited in plant-rich and plant-poor swamps, interdistributary depressions of delta plains, interfluvial depressions of meandering rivers as well as microfacies environment of natural levees and the distal crevasse splay.

Currently, the research on the shale gas in Shanxi Formation in the Ordos Basin is still in its infancy. There is yet no research on the fine-grained partition of the sedimentary facies in coal accumulation environment of Shanxi formation and the controlling effect of sedimentary microfacies over shale reservoirs.

Sedimentary facies type of the Shanxi Formation in northeastern Ordos Basin is an ongoing debate. Based on field measurements, sample collection and identification, and laboratory analysis, we systematically evaluated the sedimentary characteristics of the sandstone bodies of Shanxi Formation of Chengjiazhuang section in Liulin. Analysis included identifying sample composition, grain size, texture, sedimentary structure and spatial distribution. We came to the conclusion that the sedimentary environment of Shanxi Formation is deltaic. This deltaic environment included deltaic front and deltaic plain. It can be further divided into five sedimentary microfacies: subfluvial distributary channel, subfluvial distributary interchannel, distributary channel, levee, and peat bog. And lastly, the evolution of sedimentary environment of Shanxi Formation is discussed.

The purpose of this paper is to find the relationship of palaeontology, palaeobotany and coal thickness of Taiyuan Formation during Late Carboniferous – Early Permian Period in Shanxi Province.

This paper selects three regions, namely, Baode, Xishan and Lingchuan, to analyse the distribution characteristics of palaeontology, palaeobotany and variation of coal thickness.

It was found that in a certain period of geological history, palaeontology and palaeobotany play a dominant role in shaping of a coal-bearing basin. Coal seam thickness changes largely from the northwest to the southeast, gradually thinning in Taiyuan Formation.

Palaeontology and palaeobotany play a dominant role in the shaping of a coal-bearing basin.

The multidisciplinary Fluvalps‐3000 research project focuses on the variability of the Late Holocene and historical fluvial dynamics in alpine catchments. The purpose of this paper is to examine the potential of a 3,600 year‐long record composed from fluvial deposits for flood hazard assessment.

The research is based on a multi‐proxy approach integrating methods of various disciplines as sedimentology, geochronology, pedology, geomorphology, palynology, history, and archaeology. This paper considers particularly the sedimentological and geocronological methods applied to the fluvial records of several key sections of the Lütschine and Lombach fan deltas.

The sedimentary data of the high‐resolution fan delta record show up to seven major aggradation pulses from 3,600 cal yr BP to present. Furthermore, 19 minor burial episodes occur between 3,600 and 1,050 cal yr BP at average intervals between 113 years (Lütschine) and 105 years (Lombach) suggesting that aggradation during the focused period was triggered by centennial flood events. Nine coarse‐grained flood layers of the Lütschine record, deposited during the last 3,350 years by catastrophic flood events at a recurrence interval of 370 years, coincide with positive radiocarbon anomalies and cold phases in the Alps. The solar influence on regional hydrological regime is proposed as the main factor triggering the flooding events. However, the impact of land‐use changes in the region since 2,300 cal yr BP was detected by pollen and geochemical proxy data from fluvial deposits.

According to the results, the 2005 flood may not be considered as one of these mayor catastrophic events, thus providing useful data for future risk assessment by regional and local authorities. The 3,600 year flood history derived from fan delta proxies, presented in this paper, is unique in the European Alps.

Deterioration in natural stone is associated with many decay mechanisms and often the inherent composition of the materials themselves. Sandstone varies considerably but they all require a cementing matrix to bind amongst others, the silica (SiO₂) particles together (Reading, 1989). In calcareous sandstones and limestones this binding matrix is principally calcium carbonate based (Muir, 2006; Reading, 1989; McMillan et al., 1999) in the form of calcite (CaCO₃). Friable sandstone substrates and stones suffering from “surface dissolution” or disaggregation (Muir, 2006; Smith et al., 1992) have been traditionally consolidated utilising a host of chemical compounds that had, in many cases negative effects on their long-term performance (Muir, 2006). A principle issue amongst many was moisture entrapment and irreversibility of the consolidants adopted. The paper aims to discuss these issues.

This paper investigates the effect of microbial induced calcite precipitation (MICP) as a natural treatment for the conservation of historic natural stone substrates. Sporosarcina pasteurii has been proven as a bacterium that can perform MICP effectively in extreme conditions making it the preferred bacterium for the MICP process within this study. Surface treatment experiments were analysed by measuring the mass increase and surface changes using scanning electron microscopy (SEM).

The surface treatments showed a noticeable mass increase and observable deposition when viewed using a SEM microscope. Bio cementation of loose sand particles was observed and the degree of cementation was determined using a Moh's hardness test.

Recommendations for further work to improve this study are: use an increased Sporosarcina pasteurii cell optical density which would provide a greater calcite output. Carry out a paired comparison initial surface absorption test (BS 1881: Part 208, 1996 or ASTM C 1585-04, 2004). To be carried out on untreated control and MICP samples which would determine the pore blocking effect and surface repair capability of the treated samples.

A method for obtaining optimal results in terms of surface treatment would involve reducing the time between mixing and application, this would require having the two reaction constituents mixed only seconds before use. Using a late mix spray application system has the potential to allow the two mixtures to combine in the spray nozzle whilst exiting the apparatus.

This paper investigates a safe, natural process for stone repair.

Lithofacies and their relationships, textural content, sedimentary structures were used to delineate eight facies associations in the Benin west-1. Seven lithofacies are recognized; coarse grained sandstone with granules, laminated shaley sandstone, shaley siltstone, laminated shaley siltstone with fossil fragment, laminated shale, siltstone, coarse grained sandstone and micaceous sandstone facies. Each lithofacies is interpreted to represent different or similar depositional environments. Sediments of the Ameki Formation and Imo Shale encountered in the Benin west-1 were deposited in distributary channel and prodelta to marine shelf environments

A detailed analytical study of Leping bark liptobiolith in Jiangxi was conducted to determine its petrographic characteristics and depositional environment based on coal petrography and geochemistry. Results indicate that barkinite mainly occurs in the middle and lower coal sea4ms, whereas less barkinite and more vitrinite occur in the middle and upper coal seams. Coal facies analysis of bark liptobiolith was performed to determine its characteristics under various depositional conditions, such as the presence of a water table and gelification during coal formation. Results indicate that the environmental evolution of bark liptobiolith begins from brackish-marine swamp facies (barkinite-rich coal seam) and ends in back barrier swamp facies (barkinite-poor coal seam).

The purpose of this paper is to focus on the assessment of water resources in the Seybouse middle sub-basin. Analyses of water and various current uses are used to draw attention to the necessity of implementing water resources integrated management into a plan aiming at a rational exploitation.

Any sustainable management of water resources is closely dependent on the ability to accurately assess the quantity and quality of available water resources that are used as water supply for the population, agricultural production, industrial or energy. The analyzed and processed available data serve as database for integrated water resources management.

Analysis shows that the annual water supply is represented by 71 percent of the surface water resources and 29 percent of groundwater. The total volume of water used in the middle Seybouse basin is estimated at 36.22 hm3/yr. The predicted water needs are estimated to 79.19 hm3/yr in 2030. The groundwater of the Guelma alluvial aquifer exhibits a calcium chloride-facies general trend. The evolution of the chemical elements is related mainly to the geological nature of the reservoir lithologies. The heavy metals do not exhibit clear anomalies, but the surface water of the majority of streams is heavily infected with bacterial germs.

The obtained results show that the Seybouse middle sub-basin needs twice as much water by 2030 for the different uses. This requires a better management of water resources for a sustainable development in this specific region of Eastern Algeria.

This paper is devoted to the management of water resources in a specific region (the middle Seybouse basin) which constitutes an interesting example of considerations to be taken for a sustainable development.

The purpose of this paper is to identify and characterize a geological storage site at more than 800 m depth that is capable of storing large quantities of carbon dioxide (CO₂) in the Alberta Basin and is close to a large CO₂ supply.

Five criteria are used to select the site: total volume of the pore space of the formation for CO₂ (i.e. capacity); accessibility of the pore space in the storage site to CO₂ (i.e. permeability or injectivity); ability of the storage site to retain the CO₂ once the CO₂ has been injected (i.e. containment); protection of other resources from contamination; and cost of the whole process: capture of the CO₂, transport and storage (i.e. economics).

The Heartland Redwater Leduc Reef is identified as a site that has large capacity, good injectivity, and is an excellent trap. Contamination of the oil in the oil reservoir at the top of the reef (the third largest oil reservoir in Canada) is avoided by co‐optimizing CO₂ storage and oil production.

The Heartland Redwater Leduc Reef is ideally located at relatively shallow depth (1,000‐1,200 m), has a large amount of residual oil and is close to large CO₂ sources which make it one of the most economically attractive sites in the Western Canadian Sedimentary Basin.

The Heartland Redwater Leduc Reef Saline Aquifer CO₂ Capture and Geological Storage Project (HARP) is investigating the technical and economic feasibility of injecting significant volumes of CO₂ into the large water‐saturated portion of a huge Devonian reef that is capped by a comparatively small oil reservoir, nevertheless the third largest oil pool in Canada. The reef has a total areal extent of nearly 600 km³, is more than 1,000 m deep and is up to 275 m thick. Based on the high‐water injectivity in the reef, the potential exists to inject sustainably in excess of 1,000 tonnes of CO₂ per day per well in the aquifer portion of the reef. Preliminary storage capacity estimates for the aquifer are in the order of one gigatonne of CO₂. The Heartland Redwater Leduc Reef has the combination of a large oil reservoir sitting on top of a much larger local aquifer. This is a unique site for storage in Canada and could be a model for the rest of the world for carbon dioxide capture and storage.

The purpose of this paper is to develop a three dimensional (3D) geological model, based on geographic information system (GIS), of the Barwon Downs Graben aquifer system in Victoria, Australia, and to visualize the complex geometry as a decision support tool for sustainable water management.

A 3D visualization of the aquifer is completed, based on subsurface geological modelling. The existing borehole database, hydrogeological data, geological information and surface topography are used to model the subsurface aquifer. ArcGIS 9.2 is employed for two‐dimensional (2D) GIS analysis and for 3D visualization and modelling geological objects computer aided design (GOCAD) 2.5.2 is used. The developed methodology of ArcGIS and GOCAD is implemented for creating the 3D geological model of the aquifer system.

The 3D geomodel of the Barwon Downs Graben provides a new perspective of the complex subsurface aquifer geometry and its relation with surface hydrogeology in a more interactive manner. Considering the geometry, estimated volume of the unconfined Eastern View aquifer is as 0.83 × 10¹⁰ m³ and for the confined aquifer is about 1.02 × 10¹⁰ m³. The total volume of overlying strata of this aquifer is about 3.0⁹ × 10¹⁰ m³. The water resources of the study area are affected by the pumping from this aquifer. This is also significantly influenced by the geometry of the Graben.

The 3D model utilises comprehensive and generally available datasets in the public domain. Although the used 3D geomodelling tools are mainly developed for applications in the petroleum industry, the current paper shows its ability to be adapted to hydrogeological investigations.