2007级本科生岩石力学大作业题目

《岩石力学》大作业1.作业题目结合所学的《岩石力学》课程及相关知识，利用给出的测井数据，对地层力学参数、地应力、地层坍塌压力与破裂压力进行分析计算，作出地层力学参数、地应力、地层坍塌、破裂压力剖面，形成结课作业报告。2.已知条件地层测井数据（见附表）；地层孔隙压力当量密度为1.03g/cm3上覆主应力在3000m处地层当量密度为2.23g/cm3；地应力实测值：在3025m处实测水平最大主应力大约59MPa，水平最小主应力大约49MPa；测井过程中钻井液密度为1.35g/cm3；岩心抗压强度试验结果：井深（m）围压值（MPa）破坏强度（MPa）3030016.125106.53110022.630127.13.要求利用自然伽马测井数据简单分析地层岩性，合理设定或求取Biot系数；利用测井数据计算分析地层的弹性模量、泊松比；根据抗压试验结果，依据莫尔-库仑准则计算单点的粘聚力和内摩擦角，根据实验结果调整合理的系数，利用测井数据计算粘聚力、内摩擦角与地层抗拉强度的连续剖面；采用地层密度积分方法计算上覆主应力，根据地应力实测数据分析水平构造应力系数，采用适当模型计算水平主应力大小，得出上覆地层应力、水平最大和最小主应力剖面；采用直井完整性地层坍塌、破裂压力计算模型，不考虑渗流作用，计算地层坍塌压力和破裂压力；输出结果中单位的使用：地层强度参数采用MPa为单位，地应力、坍塌压力、破裂压力采用当量泥浆密度为单位；岩石力学作业说明1.利用自然伽马测井数据简单分析地层岩性，合理设定或求取Biot系数根据自然伽玛测井数据，由公式（1）、（2）可计算出不同井深处岩石的泥质含量。式中，——泥质的体积含量；IGR——泥质含量指数；GR，GRmin，GRmax——分别表示目的层的、纯砂岩层的和纯泥岩层的自然伽玛读数值，这里取GRmin=30，GRmax=140。GUCR——希尔奇指数，对于第三系地层取3.7，老地层取2。这里取GCUR=3.7。关于Biot系数的设定：当；；。2.利用测井数据计算分析地层的弹性模量、泊松比由声波时差数据算出纵、横声波速度，然后求出，。并通过动静转换得到，。（km/s）（3）（4）（5）（6）（7）式中，、——分别为纵波速度与横波速度。、——动态、静态弹性模量；、——动态、静态泊松比。3.利用测井数据计算粘聚力、内摩擦角与地层抗拉强度的连续剖面。C---粘聚力，----内摩察角A，a，b为经验系数，根据实测数据反算地层单轴抗拉强度和抗压强度。4.计算地应力（1）上覆岩层压力的计算上覆岩层压力梯度一般分段计算，密度和岩性接近的层段作为一个沉积层，即（2）水平主应力的计算（使用黄荣樽法（六五）：式中：是反应两个水平方向上构造应力大小的常数，即构造应力系数。由实测地应力反算5.地层坍塌压力和破裂压力（1）坍塌压力保持井壁稳定的坍塌压力公式式中,（2）破裂压力附件：测井数据井深(m)声波时差（us/ft）伽马测井密度(g/cm3)300088.34191.8662.3914300189.14389.0472.3867300290.46997.2972.3789300393.84697.4732.3597300494.66298.0542.3552300594.33297.0582.357300694.732107.432.3548300794.99490.2022.3533300895.04290.4772.3531300994.71499.392.3549301093.91990.8732.3593301193.86399.9832.3596301294.025101.422.3587301394.593103.212.3555301496.535109.062.345301596.74100.412.3439301697.264102.832.3411301798.259104.672.3358301896.26197.8122.3465301995.957101.12.3481302095.098107.812.3528302195.35994.9612.3514302295.01195.7152.3533302395.512104.892.3505302496.04996.1512.3476302596.233105.92.3466302696.12396.0092.3472302795.61699.0592.35302895.85598.2572.3487302994.896102.992.3539303095.79790.6582.349303195.731101.112.3493303294.83598.7022.3542303395.05991.3182.353303496.15103.252.3471303596.4897.6192.3453303696.16594.1162.347303796.38697.5862.3458303897.178101.22.3416303998.283102.322.3357304095.903101.342.3484304198.32104.822.3355304296.877104.42.3432304397.289107.972.341304498.078100.982.3368304597.79394.6892.3383304699.919100.252.3272304799.04797.6582.3317304899.10697.922.3314304999.106100.42.3314305099.097106.892.3315305198.417103.62.335305298.718102.082.3334305396.935105.032.3429305496.50492.3142.3452305597.092107.542.342305696.03994.0382.3477305795.90794.3712.3484305896.36998.7282.3459305995.715100.182.3494306096.759102.232.3438306199.152107.512.3312306296.50399.8312.3452306394.593.3182.3561306494.717101.192.3549306594.29198.3682.3572306694.70297.7812.355306795.64596.2542.3498306896.648100.122.3444306998.94495.1552.3323307097.973102.512.3374307196.324103.482.3461307295.13796.7372.3526307395.06287.152.353307495.97893.4362.348307595.65196.3722.3498307694.87699.6012.354307795.629104.412.3499307895.28187.1042.3518307996.144105.412.3471308095.27298.2852.3518308195.45899.2182.3508308295.292101.892.3517308395.99193.072.3479308496.375100.642.3459308596.64391.2932.3444308696.80495.8262.3436308798.09995.0442.3367308896.85697.372.3433308995.688109.832.3496309096.743102.212.3439309197.802102.982.3383309296.435105.592.3455309396.67696.2952.3442309496.677104.482.3442309596.61294.7162.3446309695.914103.422.3483309795.53893.912.3504309896.578101.072.3448309997.025100.612.3424310096.492100.892.3452310196.45994.9622.3454310296.751100.532.3438310396.299.0382.3468310497.339100.492.3407310596.284107.582.3463310694.38395.7612.3567310792.77288.3642.3657310893.86793.1272.3596310995.918109.782.3483311097.765103.122.3384311197.66996.8112.339311295.59299.9572.3501311399.029103.082.3318311499.03107.752.3318311599.03104.722.3318311699.05599.62.3317311798.969101.222.3321311899.132103.162.3313311998.458100.832.3348312096.421106.392.3456312196.3231052.3461312294.2396.762.3575312398.206103.292.3361312497.71198.5632.3387312597.214103.712.3414312696.324108.042.3461312796.35396.7592.346312896.11897.2092.3472312997.47893.0372.34313097.194103.512.3415313198.655114.852.3338313296.467107.232.3454313396.81296.9172.3435313495.6105.832.35313596.526101.262.345313696.735103.572.3439313796.47497.1742.3453313896.639100.612.3444313996.04795.592.34763