Permeability and anisotropy of IODP core samples by mobile NMR

主要目标是（1）改进和扩展迄今为止开发的NMR技术，用于在钻井现场使用Halbach扫描仪进行原位岩心分析，以及（2）设计移动的NMR设备，用于在钻井后直接对ODP和IODP程序中的水饱和岩心剖面的孔隙度和孔径分布进行常规非破坏性在线测量。上一个项目生产的设备适用于实验室研究中的原理演示和实验室附近的基础研究。对于常规调查，需要通过滑动台和舒适的操作软件进行改进。有条理的研究旨在提供实验数据的细节以外的孔径分布函数。应用于这一目的的NMR技术是多脉冲弛豫法，常规脉冲梯度NMR，NMR成像，和新的二维NMR实验，相关的弛豫时间和扩散系数的分布。通过结合图像信息、来自弛豫或扩散图的积分孔径分布函数以及来自扩散-扩散相关图的关于孔隙各向异性的积分信息，可获得一组详细数据，其最终可用于对孔隙结构和孔隙连通性进行建模，以最终获得比目前可用的更准确的渗透率估计。

The main objectives are (1) to refine and extend the NMR techniques developed so far for in¿situ core analysis at the drilling site with a Halbach scanner, and (2) to design mobile NMR equipment for routine nondestructive on-line measurements of porosity and pore size distributions of water saturated drill core sections within the ODP and the IODP program directly after drilling. The equipment produced in the previous project is suitable to demonstrate the principles in laboratory studies and to use in basic investigations near to the laboratory. For routine investigations it needs to be improved with a sliding table and comfortable operating software. The methodical study aims at providing experimental data with details beyond the pore-size distribution function. The NMR techniques applied to this purpose are multi-pulse relaxometry, conventional pulse gradient NMR, NMR imaging, and novel two-dimensional NMR experiments which correlate distributions of relaxation-times and diffusion-coefficients. By combining the image information, the integral pore-size distribution function from relaxation or diffusion maps, and the integral information about pore anisotropy from diffusion-diffusion correlation maps, a set of detailed data is available, which eventually can be used to model the pore structure and pore connectivity to finally obtain estimates of permeability more accurate than currently available.