bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adsorbed Gas Composition, and its Impact on Early Time Production
Authors: Walker G. , Branter T. , Miller P. 
Published: February 2017

Abstract
Unconventional shales can include adsorbed gas, mostly calibrated in coal seams at low pressure for CH4 and CO2, whilst also including Natural Gas Liquids and condensates. For the Duvernay formation in Alberta, Canada, the Langmuir pressure can be above 3000psia/200bar, pressures where PVT issues such as dewpoint and liquid yield are important.
The adsorbed gas released first is likely to be enriched in the lighter components, so that the composition of the gas released may not be reflective of the free gas. With an increasing proportion of dry adsorbed gas being released with pressure decline, an alteration in liquid yield can occur, even above the dew point, and this change has been observed in Duvernay production data, As initial production and gas samples will likely be representative of the free gas, such that a conventional fluid sampling and PVT analysis for dewpoint may miss the impact. The objective of this paper is to present compositional simulation work that has been completed to describe this observed behavior with a Langmuir isotherm.
The Marcellus shale has been a good training ground for understanding the impact of adsorbed gas in a dry gas system. In the Marcellus, the adsorbed gas contribution ranges from 30-50%usinghigh pressure adsorption models such as BET. When you shift from dry gas into the more liquid rich phase windows, gas condensates can have a dew point pressure in the range of 4000psia. Adsorption isotherm analysis of the Duvernay have shown Langmuir pressures in the range of 3000psia, therefore the adsorbed gas will become active as soon as the reservoir pressure drops from initial conditions.
If the adsorbed gas released is exactly the same composition as the free gas, the composition will remain unchanged, and the adsorbed gas will merely be a source of additional support, such as in the Marcellus dry gas. However, in a system with natural gas liquids and condensates, compositional effects can be anticipated, primarily with changes in the lighter ends as it is those that liberate first. In producing Duvernay wells, above the saturation pressure, changes in the C1/C2 ratio occur along with liquid yields changes appearing to indicate that the liberation of adsorbed gas in effect.
Multi-Well, Multi-Phase Flowing Material Balance
Authors: Shahamat M. S. , Clarkson C. R. 
Published: February 2017

Abstract
Flowing material balance (FMB) analysis is a practical method for determining original hydrocarbon volumes in-place. It is attractive because it enables performing material balance calculations without having to shut-in wells to obtain estimates of reservoir pressure. However, with some exceptions, its application is limited to single-phase oil and/or gas reservoirs over limited pressure ranges during depletion. In unconventional reservoirs, reservoir and/or production complexities may further restrict FMB usage. Among these complexities are significant production/injection of water, production resulting in higher Gas-Oil-Ratios and pressure drawdowns, geomechanical effects, and multi-well production effects. As a result, application of the conventional FMB to unconventional reservoirs may lead to significant errors in hydrocarbons-in-place estimation.
This paper first discusses the application of conventional FMB to the analysis of single or multi-phase flow in single or multi-well scenarios, and then provides a new, comprehensive version of the FMB to address the above-mentioned complications. For the new FMB, pseudo-pressure is used to account for two-phase oil and gas flow. In addition, by using a general material balance equation, water production/injection and multi-well effects are included in the analysis. The new FMB analysis approach is validated by comparing results against numerical simulation of multi-fractured horizontal wells (MFHWs). These comparisons demonstrate that, not only gas production, but also water production/injection, can have a significant effect on the calculated original in-place hydrocarbon volumes. The new FMB analysis approach provided herein successfully accounts for all flowing phases in the reservoir, and is demonstrated to be applicable for multi-well scenarios.
The methodology presented in this paper maintains the simplicity of FMB, yet accounts for multi-phase flow and multi-well complications. The developed FMB and the presented approach can be used by reservoir engineers to reasonably determine the original volumes of hydrocarbons in-place in both conventional and unconventional reservoirs.
Improved Characterization of Anisotropy in Tight Reservoirs Using Stiffness Tensors and Variable Biot's Poroelasticity
Authors: Shaikh Hamza , Ogunrewo Olakunle 
Published: February 2017

Abstract
Anisotropy measurements in unconventional rocks require fully characterized azimuthal rock properties. Accurate characterization of the minimum in situ horizontal stress plays a vital role in fracture modeling. Underestimation of stresses from applying the assumptions of isotropy leads to poor drilling and completion design. On the other hand, applying a simplified tensors’ assumption and assuming a constant Biot's Poroelastic Coefficient of one overestimates the stresses leading to costly drilling issues and incorrect proppant placement.
First step involves obtaining high frequency directional core samples i.e. vertical (0°), inclined (45°) and horizontal (90°) to derive five independent and continuous velocity profiles (including vertical shear and vertical compressional velocities) and mechanical properties for anisotropic models. Importance of core testing is imperative to deriving pseudo velocity profiles and for dynamic to static conversion of Young's Moduli and Poisson's Ratios. Rock physics govern static core based properties (stress-strain measurements) be used as opposed to dynamic properties measured directly from velocities for accurate characterization of stresses.
Obtaining an inclined ASTM (American Standard Testing Material) standard core plug for rock testing is one of the biggest challenges the industry is facing due to the fragile nature of shale material. Shorter core plugs lead to end-cap friction and scaling related errors by increasing uncertainty in rock properties. These challenges have forces the industry to make a simplified assumption on tenors (i.e. C12=C13) that are imperative to deriving anisotropic mechanical properties from measured azimuthal velocities. Second challenge is the characterization and validation of Biot's poroelasticity theory. Building pore pressure to measure grain compressibility to calculate Biot's constant in unconventional rock types is time consuming and costly. Therefore, many standard models assume a constant Biot's of one. The tensor and Biot's assumptions were investigated independently and fracture modeling was performed to predict the fracture geometry that was also compared with the available calibration data. It was determined that the both tensor and Biot's of one models overestimated the stresses, resulting in an inaccurate fracture geometry prediction. Finally, a variable Biot's model without the simplified tensor assumption derived using inclined velocity measurements was proposed, that composed of fully integrated anisotropic core based rock properties.
The proposed model is a useful tool to accurately characterize the geomechanical properties of unconventional rocks and hence accurately predict the resulting fracture geometry. Good understanding of the stress field around a wellbore allows operators to make informed decision regarding the drilling and completion program of the in-fill wells leading to optimum field development strategies and significant cost savings.
Imbibition Oil Recovery from Tight Rocks with Dual-Wettability Pore-Network A Montney Case Study
Authors: Javaheri Ali , Dehghanpour Hasssan , Wood James 
Published: February 2017

Abstract
Previous studies demonstrate that the Montney rock samples have a dual-wettability pore network. Recovery of the oil retained in the small hydrophobic pores is a unique challenge. In this study, we apply dual-core imbibition (DCI) method on several Montney core plugs and introduce imbibition-recovery (IR) trio to investigate the recovery mechanisms in rocks with dual-wettability pore network. First, we evaluate the wetting affinity of five twin core-plugs from the Montney Formation by measuring spontaneous imbibition of reservoir oil and brine, and by measuring equilibrium contact angle. We place one plug of each pair in the oil and the other in the brine, and measure the weight change periodically. Second, we place the oil-saturated samples in the brine to visualize the expelled oil droplets and measure volume of the recovered oil. We comparatively analyze the spontaneous imbibition data from the first step and the recovery data of the second step in one imbibition-recovery trio (oil imbibition, brine imbibition, and imbibition oil recovery). The results of air-liquid contact angle and spontaneous imbibition on dry samples suggest that the affinity of the samples to oil is higher than that to brine, in an air-liquid system. However, the results of liquid-liquid contact angle and counter-current imbibition tests suggest that the affinity of the samples to water is higher than that to oil, in a liquid-liquid system. For each twin set, the oil recovery curve follows the trend of brine imbibition curve, and the final oil recovery is always less than the equilibrated water uptake of dry samples. This observation indicates that water can only access the hydrophilic part of the pore network initially saturated with oil. Finally, we introduce a porosity-based model to analyze oil-recovery data.
Integrating Petrographic and Petrophysical Analyses with CO2 Permeation and Oil Extraction and Recovery in the Bakken Tight Oil Formation
Authors: Hawthorne Steven B. , Jin Lu , Kurz Bethany A. , Miller David J. , Grabanski Carol B. , Sorensen James A. , Pekot Lawrence J. , Bosshart Nicholas W. , Smith Steven A. , Burton-Kelly Matthew E. , Heebink Loreal V. , Gorecki Charles D. , Steadman Edward N. , Harju John A. 
Published: February 2017

Abstract
Over 40 rock samples were obtained from six Bakken wells which penetrate through the major oil pay including two shale intervals: Upper and Lower Bakken, and two tight intervals that are the targets for drilling: Middle Bakken and Three Forks. Detailed petrographic and petrophysical analyses were performed on the samples to better correlate the extraction results with the physical and geochemical properties of the rocks. Round rods (11.2-mm diameter X ca. 30–40 mm long) drilled from each of the 40 samples were individually exposed in a "bath" of CO2 for 24 hours at reservoir temperature and pressure of 5000 psi and 230°F (34.5 MPa, 110°C), and the recovered crude oil hydrocarbons were collected periodically and analyzed to determine the rates and efficiencies of oil recovery.
For the 26 Middle Bakken and Three Forks rocks, hydrocarbon recovery upon CO2 exposure averaged 86% after 7 hours, and 99% after 24 hours. Recoveries of the crude oil (not including kerogen) from the 15 Upper and Lower shales were surprisingly high with an average of 30% recovered after 7 hours, and 50% recovered after 24 hours. While the Middle Bakken and Three Forks TOC values were ca. 0.3 wt.% (similar to their crude oil content), TOCs for the Upper and Lower Bakken shales were typically 10 to 15 wt.%, with ca. one-tenth of that organic content being crude oil hydrocarbons as opposed to kerogen. The Upper and Lower shales also had significantly smaller pore throat sizes (averaging ca. 3 nm) than the Middle Bakken and Three Forks samples (which averaged ca. 10–26 nm). Additional studies are being performed to determine whether the small pore throat sizes (which approach molecular dimensions) and/or the sorption of crude oil hydrocarbons onto the kerogen in the Upper and Lower shales are responsible for the slower hydrocarbon recovery than that achieved from the Middle Bakken and Three Forks rocks under CO2 exposure.
Currently, the main targets for horizontal drilling are Middle Bakken and Three Forks, where thousands of multistage hydraulically fractured wells have been drilled in the past decade. The high oil recovery factor observed in cores from these intervals, especially when compared to the 7% average recovery in the field, indicates the huge potential for oil recovery factor improvement in these units by increasing oil production based upon supercritical CO2 extraction.
Checklist of Gastropods from the Exclusive Economic Zone (EEZ), Sarawak, Malaysia
Authors: Wan Zabidii Wan Morni  , Siti Akmar Khadijah Ab Rahim  , Richard Rumpet  , Jamil Musel  , Ruhana Hassan  
Published: February 2017

This study provides the first marine gastropod checklist from the Sarawak Exclusive Economic Zone (EEZ). Gastropod samples were collected from selected stations in the Sarawak EEZ using an otter trawl net with a stretched mesh size of 38 mm at the cod end. The trawling operations were conducted more than 12 nautical miles from the coast, and the area was divided into three depth strata: I) 20–50 m, II) 50–100 m and III) 100–200 m. A total of 23 gastropod species were identified during the two-month sampling period from 16 August until 6 October 2015, representing 8 superfamilies, 15 families and 20 genera. Superfamily Tonnoidea was represented by 7 species, followed by Muricoidea (5 species), Cypraeoidea (4 species), and Buccinoidea and Conoidea (both with 2 species). Other superfamilies were represented by a single species. Only 3 species were obtained in 2 depth strata, namely Melo melo, Murex aduncospinosus and Tonna galea. In addition, 9, 13 and 4 species of gastropods were found in strata I, II and III, respectively. The information on gastropod distributions at different depth strata in the Sarawak EEZ could be useful in updating the Malaysian species diversity database.

Kajian ini menyediakan senarai gastropod marin yang pertama dari perairan Zon Ekonomi Eksklusif (ZEE) Sarawak. Sampel gastropod dikumpul dari stesen yang terpilih di ZEE Sarawak. Operasi menunda menggunakan pukat tunda dengan saiz regangan 38 mm pada penghujung pukat. Operasi menunda dijalankan di kawasan melebihi 12 batu nautika dari pesisir pantai dan kawasan stesen dibahagi kepada tiga strata kedalaman iaitu, I) 20–50 m, II) 50–100 m dan III) 100–200 m. Sebanyak 23 spesies gastropod telah dikenalpasti sepanjang dua bulan kajian yang bermula dari 16 Ogos hingga 6 Oktober 2015 di mana ia terdiri daripada 8 superfamili, 15 famili dan 20 genus. Superfamili Tonnidae diwakili 7 spesies, diikuti Muricoidea (5 spesies), Cypraeoidea (4 spesies), Buccinoidea dan Conoidea (2 spesies). Manakala lain-lain superfamili hanya diwakili satu spesies sahaja. Didapati hanya 3 spesies berada di 2 strata kedalaman iaitu Melo melo, Murex aduncospinosus dan Tonna galea. Selain daripada itu, didapati 9, 13 dan 4 spesies gastropod dijumpai masing-masing pada strata I, II dan III. Maklumat berkenaan taburan gastropod dengan perbezaan strata kedalaman di ZEE Sarawak sangat berguna dalam pengemaskinian pangkalan data diversiti spesies di Malaysia.
DISCOURSE: CRIMINAL LIABILITY FOR THE FAILURE OF NATIONAL / REGIONAL DEVELOPMENT PLANNING
Authors: Hidayat Taufik 
Published: February 2017

National / Regional Development Planning (PPN/D) is a derivation of political promises of the head of state / region, hence the National and Regional Development Planning tends to be momentary interests of the head of state / region and / or elitists around him. The National and Regional Development Planning which is put into the program and made as a project can be colored by the elements of corruption, collusion and nepotism and that the program / project is likely to be executed at random. The liability for acts of corruption, collusion, and nepotism that leads to the failure of the National / Regional Development Planning is still noticeably blurry and so light, and limited only when the accountability report of the implementation of the National and Regional Development Planning is declared “rejected”, then the head of state / region concerned would be requested to fix it and / or he could no longer run. On the other hand, the National / Regional Development Planning must have used a large number of resources, so it is interesting to see more deeply, such as the possibility of criminal sanctions which can be imposed as a “deterrent” of a bad faith of the whole process National / Regional Development Planning. Based on those mentioned above, this paper will discuss the possibility to request criminal liability for the failure of the National / Regional Development Planning. The research method used is qualitative descriptive, using secondary data, a literature search. Since the head of state/region is the responsibility center of the government administration, the head of state / region must be responsible for the implementation of National / Regional Development Planning. The rejection of the accountability report presented by the head of state / region is a measure of the failure of the National/Regional Development Planning. Since the National / Regional Development Planning is a derivation of the political promises of the head of state / region at the time of the election campaign, the criminal offenses of fraud could be made as the basis of criminal liability for the failure of the National / Regional Development.
PENYUSUNAN PANDUAN EDUTOURISM HUTAN WISATA TLOGO NIRMOLO GUNA MEMUNCULKAN KARAKTER PESERTA DIDIK KELAS X
Authors: Ma’rifah Destri Ratna , Suryadarma I Gusti Putu 
Published: February 2017

Penelitian ini bertujuan untuk: (1) menghasilkan panduan pembelajaran yang layak digunakan sebagai alternatif sumber belajar biologi di tinjau dari aspek materi/isi, penyajian, kebahasaan, dan kegrafisan; (2) mengetahui keefektifan panduan dalam memunculkan karakter positif peserta didik (bersahabat/komunikatif, tanggung jawab, dan peduli lingkungan) selama kegiatan; dan (3) mengetahui peningkatan pemahaman peserta didik pada materi keanekaragaman lichen dan tumbuhan paku serta lingkungannya. Penelitian ini merupakan penelitian dan pengembangan dengan model 4D (define, design, develop, disseminate). Data hasil penilaian panduan, keterlaksanaan kegiatan, dan kemunculan indikator karakter peserta didik dianalisis secara deskriptif kuantitatif. Saran pengembangan produk dan saran untuk pelaksanaan kegiatan dianalisis secara deskriptif kualitatif. Data skor pemahaman dinalaisis dengan teknik gain score. Hasil penelitian menunjukkan bahwa: (1) panduan belajar layak digunakan sebagai alternatif sumber belajar biologi ditinjau dari aspek materi/isi, penyajian, kebahasaan, dan kegrafisan; (2) panduan belajar secara efektif memunculkan karakter peserta didik (bersahabat/komunikatif, tanggung jawab, dan peduli lingkungan) selama berkegiatan; dan (3) panduan belajar dapat meningkatkan pemahaman peserta didik pada materi keanekaragaman lichen dan tumbuhan paku serta lingkungannya. Kata kunci: panduan, edutourism DEVELOPING EDUTOURISM GUIDES HUTAN WISATA TLOGO NIRMOLO TO ACTUALIZE STUDENT CHARACTER OF GRADE X Abstract This study aims to: (1) developing a suitable learning guides which used as an alternative source of learning biology in terms of the material/content, presentation, linguistic, and graphics components; (2) determine the effectiveness of the guides in eliciting positive behavior of students (friendly/communicative, responsibility, and care for the environment) during activities; and (3) determine student’s improvement understanding of diversity of lichen and ferns as well as the environment. This study is a research and development with the 4D model (define, design, develop, disseminate). Data assessment the guides, activities enforceability, and the actualization of a character indicator learners analyzed quantitatively. Product development advice and suggestions for the implementation of analyzed qualitatively. The results show that: (1) the learning guides was considered very good in terms of material/content, presentation, linguistics, and graphics components; (2) during the activities, learners could actualize character of friendly/communicative, responsible, and care for the environment very positively; and (3) the learning guides could improve learner’s understanding of biodiversity of lichen and fern as well as its surroundings. Keywords: the leraning guides, edutourism
PENGEMBANGAN MULTIMEDIA BERBASIS MASALAH UNTUK MENINGKATKAN MOTIVASI BELAJAR DAN KEMAMPUAN BERPIKIR KRITIS SISWA
Authors: Sari Dwi Septiana , Sugiyarto Kristian Handoyo 
Published: February 2017

Penelitian ini bertujuan untuk: (1) mengembangkan multimedia berbasis masalah dengan materi redoks, (2) menganalisis kualitas multimedia berbasis masalah, serta (3) menguji keefektifan multimedia berbasis masalah dalam meningkatkan motivasi belajar dan kemampuan berpikir kritis peserta didik. Penelitian ini termasuk dalam penelitian dan pengembangan berdasarkan model Borg & Gall. Subjek uji coba dalam penelitian ini meliputi peserta didik kelas X SMA Negeri 6 Yogyakarta. Data dikumpulkan melalui angket untuk validasi media, lembar observasi keterlaksanaan pembelajaran, lembar observasi motivasi belajar, angket motivasi belajar, dan tes kemampuan berpikir kritis. Hasil penelitian menunjukkan bahwa (1) pengembangan multimedia berbasis masalah materi redoks dilaksanakan sesuai dengan prosedur pengembangan, (2) secara umum kualitas multimedia berbasis masalah termasuk dalam kategori sangat baik, dan (3) multimedia berbasis masalah efektif untuk meningkatkan motivasi belajar dan kemampuan berpikir kritis peserta didik pada pembelajaran materi redoks. Kata kunci: multimedia berbasis masalah, motivasi belajar, kemampuan berpikir kritis. DEVELOPING MULTIMEDIA BASED ON PROBLEM TO INCREASE STUDENT’S LEARNING MOTIVATION AND CRITICAL THINKING SKILL Abstract The aims of this research are (1) developing the multimedia based on problem in redox’s chapter, (2) analysing the quality of multimedia based on problem, and (3) testing the effectiveness of multimedia based on problem in increasing student’s learning motivation and critical thinking skill. This research used Borg & Gall research and development’s model. The subject of the research is the grade X students of SMA Negeri 6 Yogyakarta. The data were collected by using media validation’s questionnaire, learning process observation sheet, learning motivation’s questionnaire and obser-vation sheet, and critical thinking skill’s test. The results of the research show that (1) the development of multimedia based on problem in redox’s chapter is done based on the development procedure, (2) generally, the quality of multimedia which has been developed can be categorized as very good; and (3) the multimedia based on problem is effective to increase student’s learning motivation and critical thinking skill in redox’s chapter. Keywords: multimedia based on problem, learning motivation, critical thinking skill