T2分布提供了有關(guān)儲(chǔ)層巖石和流體性質(zhì)非常有用的信息,這也是NMR測(cè)井圖上的基本輸出。NMR測(cè)井的其他輸出大部分可根據(jù)T2分布計(jì)算出來(lái)。根據(jù)NMR回波數(shù)據(jù)計(jì)算出的T2分布可用來(lái)計(jì)算NMR總孔隙度、束縛流體孔隙度和自由流體孔隙度,也能用來(lái)計(jì)算滲透率、評(píng)價(jià)儲(chǔ)層質(zhì)量。通過(guò)將自旋回波信號(hào)擬合成大約3O個(gè)單指數(shù)方程來(lái)計(jì)算T2分布。每個(gè)指數(shù)方程都具有幅度A(T2)和相應(yīng)的衰減時(shí)間T2。擬合過(guò)程由數(shù)學(xué)反演技術(shù)來(lái)實(shí)現(xiàn)。反演結(jié)果是幅度A(T2),單位為孔隙度單位,對(duì)應(yīng)于每個(gè)T2值。A(T2)對(duì)T2的半對(duì)數(shù)圖稱(chēng)為 分布。T2分布以下的面積等于NMR總孔隙度。
上一頁(yè) [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44] [45] [46] [47] [48] [49] [50] [51] [52] [53] [54] [55] [56] [57] [58] [59] [60] [61] [62] [63] [64] [65] [66] [67] [68] [69] [70] [71] [72] [73] [74] [75] [76] [77] [78] [79] [80] [81] [82] [83] [84] 下一頁(yè)
發(fā)表評(píng)論 |