Abstract Carbonate rocks represent significant aquifers and reservoir rocks in many parts of the world. In this study, twenty-one carbonate samples collected from the exposed rocks at Batroun and Chekka, northern Lebanon, are studied to investigate their lithological characteristics, nannofossil content, and their acoustic and petrophysical properties. Four microfacies are recognized in the studied rocks including packstone, wackstone, wack-mudstone, and the wack-packstone. Nannofossils are detected in the top part of the studied section indicating marine-type depositional conditions for the upper Cretaceous carbonate rocks. The Petrographic analysis revealed also that the studied rocks have moderate to high porosity which is consistent with the measured porosity on core samples. The low porosity of some samples is induced by cementation, which also reduced their permeability. The bulk density varies widely because of the many diagenetic processes that impacted the studied rocks. Moreover, because the primary and secondary wave velocities (Vp, and Vs) are greatly influenced by porosity and density, the samples exhibit extreme variations in acoustic velocities from low values which characterize soft, highly-porous, rocks to higher velocities which are characteristic of compact, massive, and highly-cemented carbonates. Some relationships between the measured petrophysical and acoustic parameters are studied to investigate their mutual dependence, and discuss the impacts of rock composition and diagenetic alterations on the petrophysical properties of the collected rocks. The obtained results are also important in characterizing their mechanical strength, and in the analysis of seismic reflection profiles acquired for equivalent offshore limestone reservoirs in the Levant and the Eastern Mediterranean regions.

中文翻译：

---

黎巴嫩北部上白垩统碳酸盐岩的声学和岩石物理研究

摘要 碳酸盐岩是世界许多地区重要的含水层和储集岩。在这项研究中，研究了从黎巴嫩北部 Batroun 和 Chekka 的裸露岩石中收集的 21 个碳酸盐样品，以调查它们的岩性特征、纳米化石含量以及它们的声学和​​岩石物理特性。在研究的岩石中识别出四种微相，包括泥灰岩、泥灰岩、泥泥岩和泥泥岩。在研究剖面的顶部检测到纳米化石，表明上白垩统碳酸盐岩的海相沉积条件。岩石学分析还表明，所研究的岩石具有中到高的孔隙度，这与岩心样品上测得的孔隙度一致。一些样品的低孔隙度是由胶结作用引起的，这也降低了它们的渗透性。由于影响所研究岩石的许多成岩过程，堆积密度差异很大。此外，由于一次和二次波速度（Vp 和 Vs）受孔隙度和密度的影响很大，因此样品表现出声速的极端变化，从表征软、高孔隙率岩石的低值到表征致密、块状和高度胶结的碳酸盐。研究了测得的岩石物理参数和声学参数之间的一些关系，以研究它们之间的相互依赖关系，并讨论岩石成分和成岩蚀变对收集到的岩石的岩石物理性质的影响。获得的结果对于表征它们的机械强度也很重要，