Research Analysis Imagery

SEM-CL mosaic of quartz cement bridging across macrofracture, El Alamar Formation, Mexican Sierra Madre Oriental

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SEM-CL mosaic of quartz cement bridging across macrofracture, El Alamar Formation, Mexican Sierra Madre Oriental. Width of image is 2.5 mm. Note host-rock grains on both walls. Interpreted fluid inclusion assemblage traces and average homogenization temperature mapped. (B) Regions over which the relative timing of opening can be inferred, by overlap with layers of euhedral cement at the sides of the bridge (Becker et al., 2010). Average and range of homogenization temperature in (A) given for each timing region.Absolute timing can then be inferred from burial history information (e.g. Gray et al., 2001). The increments to the right of the bridge (orange arrow) likely formed earlier, when the fracture was smaller and quartz precipitation bridged a larger portion of the fracture. However, all observed inclusions within this region are single-phase and thus of unknown homogenization temperature. From Hooker, Ph.D. dissertation, 2012.