scholarly journals A systematic approach to history matching CBM production on a complex reservoir for a pilot test in Marshall County, WV, US

2008 ◽  
Author(s):  
Cesar A. Silva Molero
Keyword(s):  
History Matching ◽  
Systematic Approach ◽  
Pilot Test ◽  
Cbm Production ◽  
Marshall County

Relation between coalbed permeability and in-situ stress magnitude for coalbed methane exploration in Jharia and Raniganj coalfields, India

2019 ◽  
Vol 38 (10) ◽  
pp. 800-807 ◽  
Author(s):  
Rima Chatterjee ◽  
Suman Paul ◽  
Prabir Kumar Pal
Keyword(s):  
Coalbed Methane ◽  
History Matching ◽  
Horizontal Stress ◽  
In Situ Stress ◽  
Gas Content ◽  
Major Influence ◽  
Reservoir Pressure ◽  
Horizontal Drilling ◽  
Cbm Production

India is among the top five countries in the world in terms of proven coal reserves and coal production. As such, significant potential exists for commercial recovery of coalbed methane (CBM). Two coalfields, Jharia and Raniganj, located in eastern India are currently under development for CBM. This paper describes work done to determine coal seam properties, ambient stress conditions, and effects of depletion at these coalfields that influence CBM production. Coalbed permeability is a parameter that has a major influence on CBM production. Other influences include in-situ stress direction, gas content, and the application of suitable stimulation techniques. A robust methodology is required to determine both initial coalbed permeability and its relation to in-situ horizontal stress magnitudes. Coalbed permeability at the Jharia and Raniganj coalfields was estimated from porosity and known cleat spacing. Initial permeability of major coalbeds was correlated with effective horizontal stress, yielding satisfactory to very good exponential fit using data from Raniganj and Jharia wells. Acoustic televiewer image-logging tool measurements in a single well in the Jharia coalfield were used to infer a maximum horizontal stress orientation between N25°W and N25°E. Reservoir-pressure-dependent permeability models are presented for coalbeds under uniaxial strain condition. The coalbed permeability is dominated by the existing effective horizontal stresses normal to the cleats. Two prospective coal seams from Jharia have been identified through assessment of the response of horizontal stress to the decline of CBM reservoir pressure. Coalbed permeability increases with the drawdown of reservoir pressure and is exponentially related to the change of effective horizontal stress during reservoir depletion. The results of this study are to be used for production history matching for wells in Jharia and to determine optimal horizontal drilling directions for increased CBM production.

Coalbed Methane Pilots--Timing, Design, and Analysis

2009 ◽  
Vol 12 (05) ◽  
pp. 772-782 ◽  
Author(s):  
Randahl D. Roadifer ◽  
Thomas R. Moore
Keyword(s):  
Coalbed Methane ◽  
History Matching ◽  
Data Gathering ◽  
Time Frame ◽  
Assessment Process ◽  
Pilot Test ◽  
Pilot Testing ◽  
Field Development ◽  
Definitive Answer ◽  
Decision Points

Summary Four distinct sequential phases form a recommended process for coalbed-methane (CBM)-prospect assessment: initial screening, reconnaissance, pilot testing, and final appraisal. Stepping through these four phases provides a program of progressively ramping work and cost, while creating a series of discrete decision points at which analysis of results and risks can be assessed. While discussing each of these phases in some degree, this paper focuses on the third, the critically important pilot-testing phase. This phased CBM-prospect assessment process allows us toGain local knowledge early at low costProgressively acquire and compile appropriate data to assess the geological situation and reservoir conditions systematicallyIdentify and attempt to fill the most important knowledge gaps that represent the greatest uncertainties and risks to the prospectIncreasingly understand the distributions of key parameters that control reserves, deliverability, and valueStage expenditures and provide multiple decision points through the processUltimately, produce a project with very low development risk In the CBM-prospect assessment process, the pilot test serves the same function as a conventional exploration well. If it proves successful, then the prospect can be considered a discovery and can be appraised for development. By drilling, completing, and producing a cluster of wells in a CBM pilot test, short of proceeding directly to a partial development, we are able to locally dewater and depressurize the coal seam to be tested and, thereby, desorb and deliver measurable volumes of gas. If correctly implemented, the pilot test allows us to assess the local variability of key reservoir parameters, collect the information necessary to simulate the reservoir's producibility, and, thereby, estimate potential project reserves to a reasonable degree of accuracy. This paper contains roughly 30 specific recommendations and the fundamental rationale behind each recommendation to help ensure that a CBM pilot will fulfill its primary objectives of (1) demonstrating whether the subject coal reservoir will desorb and produce consequential gas and (2) gathering the data critical to evaluate and risk the prospect at the next--often most critical--decision point. Importantly, these objectives must be met in a timely manner. To do this, the specifications for the pilot are often not those that will be used for an optimized well or field-development pattern in terms of costs or production. This is intentional. The goals of piloting are different from the goals of development. So, the recommended designs are different. The pilot design recommendations focus on collecting superior data that will quantify key parameters for interpretation and simulation of the reservoir, retaining flexibility in the face of the level of uncertainty remaining after the reconnaissance phase, and arriving at a definitive answer on the coal reservoir's viability in an acceptable time frame. Detailed data-analysis methods for CBM are not discussed here--these are well covered in the literature. Rather, we focus on the importance, use, and potential pitfalls of data collected at the various phases of the assessment process. Examples are used to highlight the purpose and importance of various aspects of the data gathering and analysis. A general history-matching process--valid at the pilot-stage analysis and beyond--is presented as a guide.

Containers in Ports can be Tracked Smartly

2019 ◽  
Vol 9 (1) ◽  
pp. 39-52
Author(s):  
Dimitris Folinas
Keyword(s):  
Pilot Study ◽  
Real Time ◽  
Systematic Approach ◽  
Lessons Learned ◽  
Security Threats ◽  
Pilot Test ◽  
Unauthorized Access ◽  
The Status ◽  
Report Data ◽  
Web Platform

This article introduces a web platform to monitor cargo in containers status in real time using telematics and simulation practices. The platform was the main deliverable of a research project which aimed to strengthen security in the logistics handling procedures in port terminals. A systematic approach has been followed for its development and a pilot test was applied for tracking containers in a main port terminal. Lessons learned from this pilot study are also presented and discussed. According to the results of the pilot study, the proposed platform proved to be a useful tool for management, monitoring of the status and confrontation of security threats events, transforming the container to a “smart” container that uses sensors and systems to track and report data such as contents, unauthorized access, and physical location.

Reading Longer Words: Insights Into Multisyllabic Word Reading

2017 ◽  
Vol 2 (1) ◽  
pp. 86-94 ◽  
Author(s):  
Lindsay Heggie ◽  
Lesly Wade-Woolley
Keyword(s):  
Systematic Approach ◽  
Word Reading ◽  
Explicit Instruction ◽  
Working Memory Capacity ◽  
Reading Difficulties ◽  
Instructional Programs ◽  
Morphological Knowledge ◽  
Morphological Complexity ◽  
Reading Accuracy ◽  
Grade 3

Students with persistent reading difficulties are often especially challenged by multisyllabic words; they tend to have neither a systematic approach for reading these words nor the confidence to persevere (Archer, Gleason, & Vachon, 2003; Carlisle & Katz, 2006; Moats, 1998). This challenge is magnified by the fact that the vast majority of English words are multisyllabic and constitute an increasingly large proportion of the words in elementary school texts beginning as early as grade 3 (Hiebert, Martin, & Menon, 2005; Kerns et al., 2016). Multisyllabic words are more difficult to read simply because they are long, posing challenges for working memory capacity. In addition, syllable boundaries, word stress, vowel pronunciation ambiguities, less predictable grapheme-phoneme correspondences, and morphological complexity all contribute to long words' difficulty. Research suggests that explicit instruction in both syllabification and morphological knowledge improve poor readers' multisyllabic word reading accuracy; several examples of instructional programs involving one or both of these elements are provided.

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