頁巖氣文獻翻譯

1、SPE 125975The Role of Economics on Well and Fracture Design Completions ofMarcellus Shale Wells(馬賽勒斯頁巖井在井上的經(jīng)濟學(xué)作用和破裂設(shè)計完成)R. Schweitzer, H.I. Bilgesu, West Virginia U. R. 史懷哲,H.I. Bilgesu,西弗吉尼亞 U。Copyright 2009, Society of Petroleum Engineers 版權(quán)2009石油工程師協(xié)會This paper was prepared for presentation at th

2、e 2009 SPE Eastern Regional Meeting held in Charleston, West Virginia, USA, 2325 September 2009.This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by th

3、e Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, itsofficers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written cons

4、ent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright. (這篇文章是為在2009年9月23到25號在東方地區(qū)的查爾斯頓，西弗吉尼亞，美利堅合眾國舉行的20

5、09石油工程師協(xié)會而頒發(fā)準備的。這篇文章被為頒發(fā)通過SPE 程序委員會，跟著對關(guān)于的信息，在經(jīng)過作者提交的摘要中含有的評論而選擇。文章的目錄還沒有被石油工程師協(xié)會檢閱和是取決于作者的改正。材料不確實必然反映出任何石油工程師,它的官員或者成員的社會的位置。這篇文章的任何部分在沒有經(jīng)過石油工程師協(xié)會的寫作同意而被電子復(fù)制或轉(zhuǎn)載是不被允許的。而批準銷售的復(fù)制是限于不超過300字的摘要；用說明可以不被抄寫。摘要必須突出的標注石油工程師協(xié)會版權(quán)。)Abstract 摘要The demand for energy is increasing exponentially（按指數(shù)律的） in the U.S

6、and internationally.（在美國和國際中人們對能源的需求呈正指數(shù)的增長） As a clean source of energy, the natural gas production is gaining importance.（作為一種能源的來源，天然氣生產(chǎn)正獲得重視） Many potential sources exist for gas production in the Appalachian（阿巴拉契亞） Basin with the Marcellus shale being the largest resource in the U.S. （很多潛在能源來自于

7、在阿巴拉契亞山脈的盆中的氣體產(chǎn)生是由于美國中的最大資源的馬賽勒斯頁巖存在）This covers several states in the Eastern U.S. and plays a vital role in the future of gas production.（這些在美國東部的覆蓋物會在未來天然氣的生產(chǎn)中起到非常重要的作用）One of the unknowns of the Marcellus shale is the lack of commercially available information. （馬賽勒斯頁巖的未知之一是缺少商業(yè)上可用的相關(guān)信息）Informat

8、ion on well andcompletion designs for the Marcellus shale is rather vague（含糊的，不確定的） and tightly lipped.（關(guān)于井和為 馬賽勒斯頁巖完成設(shè)計的信息是相當?shù)哪：驼f不清的。） This information plays a key role in the production of these shale wells and can determine whether or not these wells may or may not be economical.（這些信息將會對這些頁巖井起到重

9、要作用，以及能決定這些井是否能有經(jīng)濟效益）In this study, simulations（仿真品） have been conducted with several wellbore configurations for gas production from the Marcellus shale.（在這個研究中，為了馬賽勒斯頁巖的氣體生產(chǎn)，仿真品被用在一些井眼裝置） Some of the parameters（參數(shù)） studied include lateral（側(cè)面的，橫向的） wellbore length, propped half length and the amoun

10、t of fracture stages along with others. （參數(shù)的研究包括側(cè)面井眼的長度，支撐物的半長以及大部分破裂鉆臺的總重）Economic evaluations were performed to determine the most cost efficient configuration（結(jié)構(gòu)，構(gòu)型）. （經(jīng)濟上的評價是被履行決定最有成本最有效率的配置）The average present day completion costs and projected sale price of gas are used in the calculation proc

11、ess.（氣體的平均目前日子完成成本和預(yù)測特價被在計算的過程中使用。）Introduction(簡介) Over time conventional wells gave way to unconventional wells during the mid 1980s.（在十九世紀80年代中葉傳統(tǒng)時代的井能給不合常規(guī)的井指明道路） This was primarily due to the increase in natural gas prices, unconventional wells were becoming profitable and more companies were w

12、illing to go after them. As of 2000, it became even more profitable and thus the emergence of all new gas plays such as the Marcellus,Haynesville and many others.（這主要由于天然氣價格的不斷增長，非常規(guī)井變的更有經(jīng)濟效益，許多公司更愿意追求他們。就在2000年，它變得越來越有經(jīng)濟效益，因此許多新的氣藏出現(xiàn)了，列如馬賽勒斯，海尼斯維尼以及其他很多） The Marcellus shale is contained within the

13、Devonian（泥盆紀的）/Ohio（俄亥俄） shale and has an estimated gas in place at 168 516 TCF or 70 150 (BCF/sq mile) (Armas, 2008) (Chernoff, 2008) (Sumi, 2008).（馬賽勒斯頁巖被含有在泥盆紀俄亥俄頁巖里面和在168- 516 校正溫度 或者70- 150(十億立方英尺/平方英里）(阿馬斯,2008）(切而諾夫,2008）(蘇米,2008）有一估計氣體放回原位。）According to estimates generated by Deutsche Bank（德

14、意志銀行）, the range of internal rate of return (IRR（內(nèi)部收益率）) for the Marcellus shale is72-100% (Nome, 2008).（根據(jù)經(jīng)過德意志銀行產(chǎn)生的估計, 馬賽勒斯頁巖的內(nèi)部回報率在72-100%(諾姆,2008）的。） IRR is a capital budgeting metric used by firms to decide whether they should make investments.（內(nèi)部回收率是一項公司用來衡量和決定是否應(yīng)該進行投資的編制預(yù)算的標準） It is an indica

15、tor of the efficiency or quality of an investment, as opposed to net present value, which indicates value or magnitude（大小，數(shù)量，等級）. （它是一效率的指示者或者一在投資上的品質(zhì)，如同反對從為凈賺指示對的價值或者大小的現(xiàn)值那樣）The IRR is greater for the Marcellus than for other U.S. shales, they concluded, because of premium（優(yōu)質(zhì)的，高效的） natural gas pric

16、ing due to location and relatively low royalties（礦區(qū)使用費） in Appalachia.（內(nèi)部收益率對馬賽勒斯頁巖來說比對其他美國頁巖還要重大，他們得出的結(jié)論是由于優(yōu)質(zhì)的天然氣價格所選位置以及相對來說在阿巴拉契亞較低的礦區(qū)使用費） In addition, the Marcellus is estimated to have the lowest breakeven price ($3.17) when compared to Haynesville, Barnett, Fayetteville, and Woodford shales.（此

17、外，與海尼斯維尼，巴尼特，非特維尼和伍德頁巖相比馬賽勒斯頁巖在價格的估計上已經(jīng)降到歷史最低3.17美元。） The next closest breakeven（得失相當） price was $4.73 dollars in the Haynesville. These breakeven prices come from the NYMEX（紐約商品交易所） natural gas prices required to drive the individual plays returns down to a 10% weighted average cost of capital.（下一個

18、最封閉的價格得失相當?shù)氖窃诤Ｄ崴咕S尼頁巖中的4.73美元。這些得失相當?shù)膬r格來自紐約商品交易所對天然氣價格要求的驅(qū)動加重到平均個人資本的百分之十） Notably, this study believesthat the five plays（氣藏組合） analyzed represent the “best of breed” among U.S. shale plays, and would not expect most other shale and tight gas（致密地層氣藏） plays to compare to these strong metrics (Nome, 2

19、008).（引人注意的是，這些研究表明那五個氣藏組合分析代表在美國中“最好的生產(chǎn)”頁巖氣藏組合，其他大多數(shù)頁巖和致密底層氣藏組合是不能和這些強有力的衡量標準相比的。（諾姆，2008）Another interesting point is that the total production of U.S. gas from shale predicted at year end 2011 will be nearly eight times greater than at year end 2006. （另一有趣的點是總的產(chǎn)量從在2011年末端預(yù)言的美國頁巖氣體將是在2006年末端的幾乎八倍大

20、。 ）The Woodford, Fayetteville, and Haynesville gas production are currently increasinggreatly while the Marcellus shale is not predicted to really take off until about 2010 (Nome, 2008). （伍德福德，費耶特維爾，和海恩斯維爾天然氣生產(chǎn)正在增加，同時，馬塞勒斯頁巖氣是沒有預(yù)測增長的，直到大約2010年（諾姆，2008）The slower transition inthe Marcellus is due to

21、the difficult terrain（地帶，地區(qū)）, uncertain regulator（可控制的）y environment, lack of infrastructure and proper equipment(Perkins, 2008).（馬塞勒斯頁巖過渡慢是由于地形復(fù)雜，不確定的監(jiān)管環(huán)境，缺乏基礎(chǔ)設(shè)施和適當?shù)脑O(shè)備（帕金斯，2008）。）The problem with typical Marcellus shale wells is the lack of information that has been gathered and that is commerciall

22、y available to the public. （馬塞勒斯頁巖井的典型問題是缺乏已經(jīng)收集到的信息，即可供商業(yè)用途的消息向公眾提供。）The Marcellus formation is a relatively new play and details involving ways to maximize production through well and fracture design have yet to be published.（馬塞勒斯頁巖的形成是一個比較新的發(fā)現(xiàn)，細節(jié)涉及到生產(chǎn)最大化和斷裂設(shè)計，尚未公布。） The Marcellus shale is importan

23、t due to its large size and theeconomic impact that it could have on the U.S.（馬塞勒斯頁巖是很重要的，由于其龐大的規(guī)模和它可能對美國產(chǎn)生的經(jīng)濟影響） As often happens, different companies have certain ideas about the best way to produce the Marcellus shale, while other companies have different development ideas.（正如經(jīng)常發(fā)生的，不同的公司有一定的想法的最佳

24、途徑生產(chǎn)馬塞勒斯頁巖，而其他的公司有不同的發(fā)展思路。） What is the best method to drill in the Marcellus is the question to be answered.（問題的關(guān)鍵是用什么方法在馬塞勒斯頁巖開鉆） Maybe it is vertical wells or possibly horizontal wells; maybe it is a combination of both.（也許這是垂直或水平井可能；也許它是兩者的一個組合） Maybe some areas will be better suited for vertica

25、ls due to geology.（由于地質(zhì)原因，有些區(qū)域也許更適合垂直井）Either way, these shale wells need stimulation to increase the permeability（滲透性）. （無論哪種方式，這些頁巖井需要刺激來增加滲透性）Currently, the pore spaces（孔隙空間） in shales are typically not large enough for even tiny methane molecules to flow through easily.（目前，孔隙空間通常是在頁巖沒有足夠大，甚至微小的甲

26、烷分子輕易流過） Shales may contain natural fractures due to stressfrom overlying rocks（應(yīng)力覆巖）.（頁巖可能含有天然裂縫由于應(yīng)力覆巖） Shale gas has long been produced when natural fractures are present. （頁巖氣一直存在時產(chǎn)生的裂縫。）Recently, however, there hasbeen more development of gas shales due to the use of techniques that create artif

27、icial fractures around well bores known as hydraulic fracturing（水力壓裂） (Sumi, 2008). （最近，然而，由于開發(fā)頁巖氣技術(shù)的發(fā)展，創(chuàng)造人工裂縫周圍井孔，稱為水力壓裂（墨，2008）。）The shale formations are naturally fractured, and made up of two distinct porous media, a shale matrix（基質(zhì)） and a fracture network.（頁巖地層的形成是由于自然破裂，并由不同的多孔介質(zhì)，一頁巖基質(zhì)和裂縫網(wǎng)絡(luò)共同作

28、用的結(jié)果。） Gas can be stored in the molecular size micropore space of the shale; it can also beabsorbed on the surface of the shale, or may be dissolved in the organic content of the shale.（氣體可以存儲在分子大小孔隙空間的頁巖；它也可以吸附在頁巖的表面，或可溶解在有機質(zhì)含量的頁巖中。） The shale matrix contains most of the gas stored in the reservoir

29、, but possesses a low permeability. （頁巖基質(zhì)包含大多數(shù)儲存在儲層里面的氣體，但是有一個低滲透）The fracture network has a high permeability, but a low storage capacity.（裂縫網(wǎng)絡(luò)具有較高的滲透性，但低存儲容量。） It is believed that natural gas is stored in the Devonian shales as both conventional “free” gas and as adsorbed gas, or gas that is physi

30、cally attached to the surface of the shales by Van der Waals-type forces (Lane, 1990).（據(jù)認為，天然氣是儲存在泥盆紀頁巖作為傳統(tǒng)的“自由氣”，如吸附的氣體，或是由物理上范德華力吸附在頁巖的表面（巷，1990） Thesenatural fractures and adsorbed gas have to be accounted for in the reservoir modeling.（這些天然裂縫和吸附氣要在儲層建模中計算。）Approach （處理）A study was conducted usin

31、g a reservoir modeling software package to investigate the gas production from the Marcellus shale.（進行了一項研究，利用儲層建模軟件包研究馬塞勒斯頁巖的氣體生產(chǎn)。） The objective was to compare and contrast the gas production in vertical and horizontal wells with varying fracture half lengths and horizontal lateral lengths.（目的是比較和

32、對比的天然氣生產(chǎn)中的垂直和水平井不同的斷裂長度的一半水平方向的長度。） This paper discusses the Marcellus shale wells along with economic results from this study.（本文討論的是馬塞勒斯頁巖井隨著經(jīng)濟發(fā)展的結(jié)果這項研究。）Reservoir modeling and simulation was conducted using Marcellus shale properties to calculate gas production rates in order to determine economi

33、c feasibility（可用性）.（為確定經(jīng)濟可行性，儲層建模和仿真是利用馬塞勒斯頁巖特性計算產(chǎn)氣率的） Prior to runs with Marcellus shales properties, a Barnett shale well was modeled using the same software and the results were compared to field production data.（馬塞勒斯頁巖之前的運行性能是通過與巴內(nèi)特頁巖是模仿使用相同的軟件和結(jié)果對現(xiàn)場生產(chǎn)數(shù)據(jù)進行了比較。） The primary purpose of the run con

34、ducted for the Barnett shale reservoir was to validate the model setup used in the Marcellus reservoir.（巴內(nèi)特頁巖儲集層程序控制的主要目的是用來驗證該模型設(shè)置用于馬塞勒斯儲層。） Once, all of the production data was simulated, an economic analysis was conducted to determine the most optimal（最優(yōu)的） designs for the parameters（參數(shù)） studied.（

35、曾經(jīng)，對所有的生產(chǎn)數(shù)據(jù)進行了模擬，經(jīng)濟分析，確定最優(yōu)設(shè)計參數(shù)研究。） In order to determine economic feasibility, first a cash flow model was constructed for all of the simulated runs.（為了確定經(jīng)濟可行性，首次軟頁巖流模型構(gòu)造所有的模擬運行。） Once the cash flow charts were constructed, net present values (NPV) can be calculated along with internal rates of retu

36、rn (IRR). （一旦現(xiàn)金流量圖表建造，凈現(xiàn)值（凈現(xiàn)值）可以計算與內(nèi)部收益率（回報率）。）These two values are used to analyze the economic feasibility of the design parameters considered in this study.( 這兩個值是本研究用來分析經(jīng)濟可行性的設(shè)計參數(shù)。） All equations used in the economic analysis are based on theory published in books (Newman (1988) and Ikoku (1985)

37、. （所有方程中使用的經(jīng)濟分析理論都是依據(jù)出版的書籍（紐曼（1988）和ikoku（1985）。）The main parameters needed were: Capital Expenses or Investment, Operating Expenses, Interest rate and Gas price.（主要參數(shù)需要：資本支出或投資，經(jīng)營費用，利息率和天然氣價格。） In a cash flow model, investment is defined as the sum of all costs.（在現(xiàn)金流模型，投資是指的總和的所有費用。） The capital ex

38、penses used in the economic analysis for drilling a horizontal well of varying lateral lengths along with the cost associated with drilling the vertical well are given in（資本支出的經(jīng)濟分析水平井鉆井的不同側(cè)面長度隨著成本與鉆垂直井的進度）Table 1. The costs of fracture treatment per stage depending on the fracture half length employ

39、ed in this study are shown in（表1。受雇于本研究的破裂處理費用每階段取決于裂縫半長） Table 2. All cost values used are general averages based on personal communications with different operators.（表2。所有的成本價值使用的是一般的基礎(chǔ)上平均個人通信與不同的運營商。） Operating costs were assumed to（假設(shè)） remain constant at thirty dollars a day per well. A fixed（固定

40、利率） interest rate of 15% is used throughout the economic study.（在整個經(jīng)濟研究經(jīng)營成本被認為保持在每天三十美元每井。固定利率15%的使用。） A constant gas price of 3 dollars per MSCF（千標準立方英尺） was also used in this study followed by a constant price of 6 dollars per MSCF.（恒天然氣價格3美元千標準立方英尺也被用于這項研究之后，一不變價格6美元千標準立方英尺隨之出現(xiàn)。） This may be a ve

41、ry conservative number for gas price considering todays gas price is 3.33 dollars per MSCF.（這可能是一個非常保守的數(shù)字為天然氣價格考慮到今天的天然氣價格為3.33美元千標準立方英尺。） Thus the 6 dollars cost was used to analyze the difference between the two values.（因此，6美元是用來分析之間的差異值。） Along with thefact that the price of gas is projected to i

42、ncrease at some point in the next ten years, however, a conservative economic analysis is used to prevent overestimation（過高估計） of costs for the project.（事實上，石油價格預(yù)計將增加，在未來的十年，然而，一個保守的經(jīng)濟分析是用來防止過高成本的項目。） In addition, a 12.5% royalty tax was taken out of the totalgas revenue.（此外，12.5%的版稅稅率是從總天然氣收入來的。） F

43、or all cases, the same parameters were used and the economic results were calculated for the first ten years of the wells life.（在所有情況下，對一個十年井的壽命用同樣的參數(shù)和使用的經(jīng)濟效益進行了計算。） Table 3 lists the economic parameters used in the analysis.（表3列出了經(jīng)濟指標分析中的應(yīng)用。）Discussion of Results（討論結(jié)果） The results of economic analy

44、sis for all $3/MSCF cases are given in Table 4. （從經(jīng)濟分析結(jié)果為所有3美元/ 千標準立方英尺，情況見表4。）The results are color coded in light blue for uneconomical results and color coded in dark blue for economical designs.（結(jié)果是彩色編碼在淺藍色不合算的結(jié)果和彩色編碼在深藍色經(jīng)濟的設(shè)計。） The final results from the data discussed above showed that no sing

45、le fractured horizontal or vertical wells were economical.（從最后結(jié)果數(shù)據(jù)上面討論結(jié)果表明，沒有單一裂縫水平或垂直井更具有經(jīng)濟性。） Only the 1000-foot fracture half length well with three fractures was economical regardless of lateral length or spacing. （無論長度或距離只有1000英尺的裂縫半長和三個裂縫是具經(jīng)濟性的。）The same was true with five fractures, except no

46、w a 750 foot and 1000 foot half lengths were economical regardless of lateral length and spacing.（同樣是真實的，有五個裂縫的，無論橫向長度及間距現(xiàn)在除了一個750英尺和1000英尺長度的一半是經(jīng)濟的。） As for seven and nine fracturetreated wells 500, 750, and 1000 foot half lengths were economical regardless of lateral lengths. （對于七和九個裂縫的井無論橫向長度500，

47、750，和1000英尺長度的一半是經(jīng)濟的無論橫向長度。）From the IRR results it was shown that larger amounts of fractures had higher IRRs.（從內(nèi)部收益率的結(jié)果表明，大量的裂縫是有較高的收益率的。） Also, well designs with the same amount of fractures had higher IRRs with longer fracture half lengths yet when the different lateral lengths are considered th

48、e shorter lateral lengths actually had higher IRRs.（此外，井設(shè)計與同樣數(shù)量的裂縫有較高的內(nèi)部收益率的較長的斷裂長度的一半當不同的橫向長度被認為是較短的橫向長度其實有較高的收益率的。） The results of economic analysis for all $6/MSCF cases are given in Table 5.（從經(jīng)濟分析結(jié)果為所有6美元/千標準立方英尺，情況見表5。） The results are color coded in light blue for uneconomical results and colo

49、r coded in dark blue for economical designs.（結(jié)果是彩色編碼在淺藍色不合算的結(jié)果和彩色編碼在深藍色的經(jīng)濟設(shè)計。） The final results differ quite a bit from the 3 dollar gas pricing.（最后的結(jié)果有很大的差異從3美元天然氣價格。） Due to the price change, 24 more of the original well and fracture designs now become economical.（由于價格變化，24以上的原井和斷裂設(shè)計已成為經(jīng)濟的。） Now

50、vertical wells become economical with a 750 and 1000 foot fracture half length regardless of the amount of wells.（現(xiàn)在，不論金額的垂直井與750和1000英尺的裂縫半長成為經(jīng)濟的。） Also three and five stage fracture treatments now become economical in all fracture half length treatments except in the 250 foot fracture half lengths

51、.（三和五階段的裂縫處理已成為經(jīng)濟中的所有裂縫半長的處理除了在250英尺處裂縫的一半長度。） Once again, the IRR showed that the well designs with larger amounts of fractures had higher IRRs.（再次，內(nèi)含報酬率表明，井設(shè)計與大量的裂縫有較高的收益率的。） Also, for well designs with the same amount of fractures, higher IRRs were found with longer fracture half lengths yet when

52、 looking at the different lateral lengths the shorter lateral lengths actually had higher IRRs.（此外，以及設(shè)計與同樣數(shù)量的骨折，高回報率的發(fā)現(xiàn)較長的斷裂長度的一半回看的時候不同的橫向長度與較短的橫向長度卻有較高的收益率的）Figure 1 shows a graphic representation of the economic evaluation（評估） of the NPV values.（圖1顯示的圖形表示的經(jīng)濟評價凈現(xiàn)值價值。） From left to right the number

53、 offracture treatments increases, and in those fracture sections the half length increases from left to right as well.（從左至右數(shù)裂縫處理的增加，并在這些裂縫部的一半長度的增加從左至右。） In the graphical representation, it can easily be seen that larger the amount of fractures and higher the fracture half length, the larger the pro

54、fit and more economical is the well.（在圖形表示，它可以很容易地看到，數(shù)額較大的裂縫和裂縫的一半長度，有較大的利潤和更好的經(jīng)濟。） The red color is the economical study done with 3 $/MSCF gas price shown in the foreground and the blue color is the study done with 6 $/MSCF shown in the background.（紅顏色是經(jīng)濟的研究做了3美元/千標準立方英尺 天然氣價格顯示在前景與藍顏色是研究做了6美元/千標準

55、立方英尺 顯示在背景中。） This figure shows the larger difference in the NPV values and between the two different gas prices.（此圖顯示了較大的差異，凈現(xiàn)值和兩者之間的不同天然氣價格。） The results discussed above are shown in Table 6 for wells with seven fracture designs. （討論的結(jié)果是示于表6井與7裂縫設(shè)計。）As discussed earlier, wells with seven fractures

56、, the only economical results are with half lengths of either, 500, 750 or 1000 feet regardless of length for three dollar gas pricing and all seven fracture treatments were economical at 6 dollar per MSCF gas pricing.（如前面所討論的，井7裂縫，唯一的經(jīng)濟效果與長度的一半或者500，750，或1000英尺，不論長度三美元的天然氣定價和所有7裂縫的經(jīng)濟在6美元每千標準立方英尺天然氣

57、定價。） As seen in Tables 4 and 5 and Figure 1, as the amount of fractures and half length distance increases the IRR and NPV values increase as well.（如在表4和表5和圖1，為大量的裂縫和一半長度的距離增加的內(nèi)部收益率和凈現(xiàn)值價值增加。） As for the difference in lateral lengths it is very close, but actually it doesnt pay to drill the extra 100

58、0 feet of wellbore if you can put the same amount of fracture in the smaller wellbore.（至于差異外側(cè)的長度是非常密切的，但實際上它不付鉆額外的1000英尺如果你能把井相同數(shù)量的裂縫在較小的井。） The shorter wellbores are actually more costefficient over this time period.（在這一時間內(nèi)較短的井筒是更實際的有效成本。）Conclusions（結(jié)論） The Marcellus shale has tons of potential in

59、 this developing play.（馬塞勒斯頁巖在這發(fā)展的過程中有著巨大的潛力。） From this study with given costs, horizontal wells werefound to be more economical when compared to the vertical wells.（從這個考慮成本的研究，水平與垂直井相比有更多的經(jīng)濟性。） Vertical wells were found to be economical in the higher gas pricing scenario（方案）.（垂直井被認為是經(jīng)濟的高天然氣定價方案。） In general when economics were considered, it was shown that the longer fractured half length of 1000feet and maximizing the number