This work characterizes the rock-mechanical properties and in-situ stress magnitudes of the Cenozoic sedimentary succession encountered in the ODP Leg 161 holes of the western Mediterranean Sea. This study attempts to infer the link between the variation of the rock-mechanical parameters within the Pliocene–Pleistocene stratigraphy with mineralogy and depositional environment. Wireline logs and bulk mineralogical compositions of five scientific holes drilled in the Central Tyrrhenian Basin (974C), South Balearic margin (975C) and Alboran Basin areas (976B, 977A and 979A) were evaluated. Study infers that a lower sedimentation rate in the greater water depths of the Central Tyrrhenian Basin resulted in increased inter-grain bonding and thus higher rock strengths in the Hole 974C sediments when compared to the other drilling sites. Estimated Young’s modulus and elastic property-based brittleness index gradually increase with depth within the lower part of the Pliocene–Pleistocene formation as carbonate % increases in response to the depositional environment shifting from Pleistocene hemipelagic environment to pelagic condition in Pliocene. Our results indicate that the rock strength and elastic brittleness properties can be utilized as confident geological proxies for depositional environments in the western Mediterranean sea region. Density-derived porosity shows an overall normal sediment compaction trend yielding hydrostatic pore pressure. Interpreted vertical stress (13.68–17.45 MPa/km) and minimum horizontal stress (12.19–14.56 MPa/km) gradients infer a normal to strike-slip tectonic regime. Due to the unavailability of calibration data, we inferred the upper bound of maximum horizontal stress (S_H) gradient, ranging between 13.88 and 18.47 MPa/km. E-Quality wellbore breakouts interpreted from the acoustic image logs in Miocene Basement (Hole 976B) suggested NW–SE to N-S S_H azimuth western Alboran Basin, parallel to the African and Eurasian plate movement direction.

这项工作描述了在地中海西部 ODP Leg 161 孔中遇到的新生代沉积层序的岩石力学特性和地应力大小。本研究试图推断上新世-更新世地层中岩石力学参数变化与矿物学和沉积环境之间的联系。对在第勒尼安盆地中部 (974C)、巴利阿里南部边缘 (975C) 和奥尔博兰盆地地区 (976B、977A 和 979A) 钻探的五个科学孔的电缆测井和大块矿物成分进行了评估。研究推断，与其他钻井地点相比，第勒尼安盆地中部较大水深中较低的沉积速率导致颗粒间结合增加，因此 974C 孔沉积物中的岩石强度更高。估计的杨氏模量和基于弹性特性的脆性指数随着上新世-更新世地层下部的深度逐渐增加，因为碳酸盐百分比随着沉积环境从更新世半远洋环境转变为上新世的远洋条件而增加。我们的结果表明，岩石强度和弹性脆性特性可用作西地中海地区沉积环境的可靠地质代理。密度衍生的孔隙度显示出总体正常的沉积物压实趋势，产生静水孔隙压力。解释的垂直应力 (13.68-17.45 MPa/km) 和最小水平应力 (12.19-14.56 MPa/km) 梯度推断出正常到走滑构造体制。由于无法获得校准数据，_H ) 梯度，范围在 13.88 和 18.47 MPa/km 之间。从中新世基底（976B 孔）声学图像测井中解释的 E-Quality 井眼突破表明 NW-SE 到 NS S _H方位角西阿尔博兰盆地，平行于非洲和欧亚板块运动方向。