周月明 章成廣 蔡明

摘 ? ? ?要：由于致密砂巖儲(chǔ)層低孔低滲，裂縫發(fā)育程度是影響其產(chǎn)能的重要因素，評(píng)價(jià)裂縫對(duì)其開(kāi)發(fā)具有重要意義。塔里木克深地區(qū)為防止鉆井液的污染，大多采用油基鉆井液進(jìn)行鉆井，大大增加了對(duì)致密砂巖儲(chǔ)層中裂縫評(píng)價(jià)的難度。針對(duì)這一問(wèn)題，從全波列橫波信息探討了聲波測(cè)井在致密砂巖儲(chǔ)層中裂縫評(píng)價(jià)的方法及應(yīng)用。考慮巖性、物性的影響，通過(guò)陣列聲波數(shù)據(jù)提取出橫波衰減系數(shù)，然后根據(jù)實(shí)驗(yàn)得到的衰減系數(shù)與裂縫寬度的關(guān)系，反演出裂縫寬度，進(jìn)而反演出裂縫滲透率。同時(shí)根據(jù)成像資料，得到的裂縫等級(jí)與根據(jù)孔隙度得到的儲(chǔ)層等級(jí)建立了與產(chǎn)能的關(guān)系。利用該方法得到的裂縫滲透率與成像解釋成果圖對(duì)應(yīng)良好，并且最終的產(chǎn)能等級(jí)整體與試油結(jié)論相吻合，表明利用橫波信息在致密砂巖裂縫評(píng)價(jià)中的效果好。

關(guān) ?鍵 ?詞：裂縫評(píng)價(jià);陣列聲波;橫波滲透率;克深地區(qū)

中圖分類(lèi)號(hào)：TE122.2+4 ? ? ? ?文獻(xiàn)標(biāo)識(shí)碼： A ? 文章編號(hào)： 1671-0460（2019）12-2844-04

Abstract： For tight sandstone reservoirs， the degree of crack development is an important factor affecting their productivity due to their low porosity and low permeability. In order to prevent the pollution of drilling fluids in Tarim Keshen area， oil base drilling fluid is always used during drilling， which greatly increases the difficulty of evaluating cracks in tight sandstone reservoirs. Aiming at this problem， the method of acoustic wave logging in the evaluation of fractures in tight sandstone reservoirs was developed from the aspect of full-wavelength shear wave information in sonic data. Considering the influence of lithology and physical properties， the shear wave attenuation coefficient was extracted from the array acoustic data， and then the crack width was inversed according to the relationship between the attenuation coefficient and the crack width obtained by the experiment， and then the crack permeability was inverted. According to the imaging data， the crack grade obtained from the crack parameters and the reservoir grade obtained from the porosity were used to establish an evaluation method that can be well correlated with the productivity. The fracture permeability obtained by this method was in good agreement with the imaging interpretation result map， and the final productivity grade was consistent with the test oil conclusion， showing that the shear wave information was good effect in the evaluation of tight sandstone cracks.

Key words： Crack evaluation; Array sound wave; Transverse wave permeability; Keshen area

塔里木盆地克深地區(qū)目的層為致密裂縫性低孔砂巖儲(chǔ)層，具有儲(chǔ)層巖性復(fù)雜、基質(zhì)儲(chǔ)層物性差、裂縫發(fā)育等特點(diǎn)。由于低孔低滲，裂縫不僅是油氣儲(chǔ)集空間，它的存在還改變了儲(chǔ)層的滲流特性[1]，所以裂縫發(fā)育程度是影響該區(qū)產(chǎn)能的重要因素，能夠有效評(píng)價(jià)裂縫對(duì)其開(kāi)發(fā)具有重要意義。起初，在裂縫識(shí)別方法上是以常規(guī)測(cè)井為主。隨著電子技術(shù)和測(cè)量技術(shù)的迅猛發(fā)展，Kitsunezaki 于 1980 年進(jìn)行了偶極橫波測(cè)井的研究，在淺層裸眼井中獲取了可靠的橫波信號(hào)。1984 年，美孚石油公司的 Zemanek 等首次研究完成了偶極聲波測(cè)井技術(shù)，在現(xiàn)場(chǎng)硬地層和松散地層中進(jìn)行了橫波數(shù)據(jù)連續(xù)測(cè)量。1985 年，Everhart 和 Chang 針對(duì)套管井中進(jìn)行偶極橫波測(cè)井進(jìn)行了理論研究[2]。章成廣[3]等利用聲波全波資料識(shí)別氣層的理論基礎(chǔ)、識(shí)別氣層的方法研究。唐軍[4]等分別從斯通利波、縱橫波以及交叉偶極子聲波等3方面拓展了聲波測(cè)井在裂縫定量刻畫(huà)中的應(yīng)用，并考慮裂縫徑向延伸特性，建立了與產(chǎn)能關(guān)系密切的裂縫測(cè)井評(píng)價(jià)模式。宋祎[5]等提出一種新的利用全波列聲波測(cè)井資料識(shí)別氣層的方法，即速度幅度聯(lián)合法，根據(jù)縱波和橫波在氣層中速度和幅度的變化來(lái)識(shí)別氣層。張曉波[6]等分別對(duì)帶井眼補(bǔ)償?shù)穆曀贉y(cè)井、聲波全波列測(cè)井、超聲成像測(cè)井和多極子陣列聲波測(cè)井等新一代的測(cè)井方法的原理、特點(diǎn)及應(yīng)用現(xiàn)狀進(jìn)行了闡述，以及在地層評(píng)價(jià)中的作用進(jìn)行實(shí)例分析和應(yīng)用效果評(píng)價(jià)。劉宇[7]針對(duì)陣列聲波測(cè)井的傳播理論、數(shù)值模擬算法、陣列波形數(shù)據(jù)的處理與反演以及地質(zhì)與工程應(yīng)用進(jìn)行了較深入的研究。胡紅[8]等用陣列聲波資料進(jìn)行井旁裂縫的識(shí)別、儲(chǔ)層流體性質(zhì)的判別、水力裂縫壓裂高度的預(yù)測(cè)和確定等。