Depositional characterization of the Eau Claire Formation at the Illinois Basin - Decatur Project: facies, mineralogy and geochemistry

The Cambrian-age Eau Claire Formation serves as the primary seal at the Illinois Basin – Decatur Project (IBDP), a one million tonne carbon capture and storage demonstration project located in Decatur, Illinois. The Eau Claire Formation conformably overlies the Mt. Simon Sandstone, the reservoir for the IBDP. At the IBDP site, analysis of drill core and geophysical logs reveals the Eau Claire consists of two major lithostratigraphic units: a siliciclastic dominant lower unit and a carbonate dominant upper unit. Within the Eau Claire, four major depositional facies exist within a tidally influenced, shallow marine depositional environment. These include (Unit A) intertidal mixed sand/mud flats and tidal channels of the foreshore environment; (Unit B) subtidal deposits of the offshore transition zone; (Unit C) subtidal deposits of the upper shoreface environment; and (Unit D) subtidal mixed carbonate/siliciclastic deposits. An approximately +8‰ δ13C excursion (R2 = 0.97) defines the Eau Claire at the IBDP site, possibly correlative with the Steptoean positive carbon isotope excursion (SPICE) found worldwide 500– 495 Ma ago. This study aims to elucidate the depositional environment, seal quality, age and provenance of the Eau Claire Formation in central Illinois. The mineralogy of the four depositional facies varies widely throughout the Eau Claire, with a persistently high K-feldspar content. The K-feldspar mode averages 8.7% for the formation and reaches an average of 20.3% in Unit C. Unit A is approximately 30 ft. (9.1 m) thick and exhibits intense bioturbation, ripple beds, and flaser/lenticular bedding, with an average porosity and permeability (n = 20) of 6.7% and 8.6 mD. Unit B is an approximately 40 ft. (12.2 m) thick tight shale sequence, with thin siltstones interbedded throughout. Unit B represents the most desirable seal facies in the formation with an average porosity (n=9) and permeability (n=4) of 5.6% and 2.0x10-5 mD. Unit C is the largest siliciclastic unit in the formation, spanning an average of 95 ft. (29 m) in all three wells at the IBDP. Unit C exhibits the classic tidalite signature of rhythmically interbedded siltstones and shales, with an average porosity and permeability (n = 50) of 9.4% and 0.9 mD. Unit D spans approximately 345 ft. (105.2 m) and begins as a mixed siliciclastic/carbonate environment, slowly becoming a dolomitized carbonate shelf dominated by oolitic packstone and grainstone

Современное состояние электрификации России

В статье показано, что современное развитие электрификации РФ в сопоставлении с государствами, входящими в G8, очевидно недостающее. При этом есть большой потенциал электросбережения в секторах экономики. Потребление электроэнергии населением существенно находится в зависимости от значения их денежных доходов и темпов роста тарифов на электричество

Memory requirement optimization with loop fusion and loop shifting

Loop fusion and loop shifting are well recognized loop transformations for memory requirement reduction. Stateof-the-art optimizations with loop fusion and shifting are based on heuristics without any evaluation of the resulting effects during each optimization step. Thus we cannot guarantee that each step results in a reduced overall memory requirement. On the other hand, most memory requirement estimations at system level are inefficient and slow. Also the estimation is not started until the optimization is done. Having to iterate between optimization and estimation is very time consuming. In this paper, we present a storage requirement optimization method which combines the optimization and estimation processes with the goal to have continuous estimates during the optimization and hence to achieve lower memory requirements. 1

Experience with widening based equivalence checking in realistic multimedia systems

Designers often apply manual or semi-automatic loop and data transformations on array and loop intensive programs to improve performance. For the class of static affine programs, automatic methods exist for proving the correctness of these transformations. Realistic multimedia systems, however, often contain constructs that fall outside of this class. We present an extension of a widening based approach to handle the most relevant of these constructs, viz. accesses to array slices and data dependent accesses, and report on some experiments with non-trivial applications.status: publishe

Experience with widening based equivalence checking in realistic multimedia systems

The application of loop and data transformations to array and loop intensive programs is crucial to obtain a good performance. Designers often apply these transformations manually or semi-automatically. For the class of static affine programs, automatic methods exist for proving the correctness of these transformations. Realistic multimedia systems, however, often contain constructs that fall outside of this class. We present an extension of a widening based approach to handle the most relevant of these constructs, viz. accesses to array slices, data dependent accesses and data dependent assignments, and report on some experiments with non-trivial applications.status: publishe

Printed in the United States of America Systematic Preprocessing of Data Dependent Constructs for Embedded Systems

Data transfers and storage are dominating contributors to the area and power consumption for all modern multimedia applications. A cost-efficient realisation of these systems can be obtained by using high-level memory optimisations. This paper demonstrates that the state-of-the-art memory optimisation techniques only partly can deal with code from real-life multimedia applications. We propose a systematic preprocessing methodology that can be applied on top of the existing work. This opens more opportunities for existing memory optimisation techniques. Our methodology is complemented with a postprocessing step, which eliminates the negative effects of preprocessing and may further improve the code quality. 13 � 18 Our methodology has been applied on several reallife multimedia applications. Results show a decrease in the number of main memory accesses up to 45.8 % compared to applying only state-of-the-art techniques