Scaling and connectivity of joint systems in sandstones from western Norway

摘要: Abstract The scaling properties of a joint system in Devonian sandstones western Norway have been investigated using seven maps, covering areas from 18 to 720 m across, which were generated by mapping the field and low-level aerial photography taken different heights. Each map represent scale ‘window’ on fracture population, bounded resolution at small scales sample size large scales. A power-law relationship between trace length critical observation height (maximum can be identified) is derived used create statistical model for effects. indicates that continuous smooth curve without straight-line segment log-log cumulative frequency distribution plot does not necessarily rule out power law as underlying population distribution. Together, maps indicate powerlaw trace-length with an exponent −2.1. This may valid over four or more orders magnitude, natural lower cut-off around 1 m. significantly −2.0 (strictly selfsimilar case) reflected decrease abundance fractures comparable size, decreases. results apparent connectivity, decreasing scale. High (large-scale) are well connected while lowest (smallest scale) unconnected. Fractures smallest are, however, below limit resolution, represented largest map. variation connectivity has implications fluid flow. When open flow imply that, beyond certain scale, controlling will scale-independent. In this system, appears occur 300 across.