摘要：A significant portion of the global hydrocarbon reserves are found in carbonate reservoirs, and these reservoirs are also key to the exploration in deep and ultradeep reserves in China. However, the complex pore structure leading to unclear understanding of the petrophysical properties of deep carbonates, resulting in a number of challenges to reservoir characterization and fluid prediction. Up to now, there is a lack of systematic rock physics experimental studies in deep carbonates at seismic frequencies. It is thus of great significance in a series of geophysical applications to clarify the role of reservoir pressure and pore fluid variations, due to hydrocarbon depletion induced fluid movements in producing fields, on seismic elastic properties. In this laboratory study, we investigate the influence of pressure and pore fluid on rock elastic moduli and its associated attenuation, through experimental measurements of elastic properties of a saturated tight carbonate at low seismic and ultrasonic frequencies. For the carbonate core with low porosity and low permeability, we evaluate the sensitivity of measured elastic moduli under dry, brine and glycerin saturation to pressure and frequency. We demonstrate that the frequency-dependence of dry Young's modulus is significantly lower than those of fluid saturated core and, the moduli and attenuation in glycerin saturated case are higher than the measurements in brine saturation. The measurements with partial brine saturation show that both Young's modulus and Poisson's ratio increase with brine saturation, yet their dispersion magnitude decreases slightly. Under the assumption of frequency-independent dry elastic properties, the measured Young's modulus and its associated attenuation of the saturated rocks from forced oscillation experiments, which are still scarcely investigated, are in fairly good agreement with predictions of the squirt model with three porosity types at seismic frequencies.

关键字：Seismic frequencies; Dispersion and attenuation; Tight carbonate; Squirt flow; Pore structure

ISSN号：0001-5733

卷、期、页：卷66期12：5141-5156

发表日期：2023-12-01

影响因子：0.000000

期刊分区（SCI为中科院分区）：四区

收录情况：SCI（科学引文索引印刷版）,地学领域高质量科技期刊分级目录（国内T1）,SCIE（科学引文索引网络版）

发表期刊名称：地球物理学报 - CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION

参与作者：未睍,李皓,张家良,潘树林,马宵一,刘卫华

通讯作者：闫国庆

第一作者：贺艳晓,唐跟阳,王尚旭

论文类型：期刊论文

论文概要：贺艳晓,闫国庆,未睍,唐跟阳,王尚旭,李皓,张家良,潘树林,马宵一,刘卫华，Experimental mechanism of elastic parameters in saturated carbonate at seismic frequencies: role of pressure and pore fluid，地球物理学报 - CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION，2023，卷66期12：5141-5156

论文题目：Experimental mechanism of elastic parameters in saturated carbonate at seismic frequencies: role of pressure and pore fluid