Outside the Interzone
Outside the Interzone 's Latest Posts
There are a number of calcite amygdules in this photo; the largest is in the upper center, and there are several smaller ones nearby. This spot sometimes gets overgrown with brambles, then a road crew will come through and clear them out. Over the next few years, the brambles will grow back, and the cycles repeats. So don't count on being able to find this spot, but it's definitely worthwhile looking for it.Photo unmodified. June 14, 2014. FlashEarth location.
At the southwest (downstream, toward the dam) end of the basalt outcrop near Green Peter Dam, there is what I would guess is a different flow of vesicular basalt. (It's unclear to me just how many individual flows are present in this outcrop.) The vesicles in this flow are less abundant, but much larger than elsewhere, and entirely filled with calcite. In addition, due to shearing in the flowing lava, they are typically pulled out into flattened teardrop-shaped lenses, reminiscent of almonds, […]
A closer view of yesterday's vesicular basalt. This shot is close enough that in crops of the full-size image, one can make out the individual blades. Compare the shape of the circled bits below to the diagrams and photos at this site. I will say, I take issue with their claim that "single individual crystals are very uncommon." Larger crystals that are not in clusters are not common, but smaller crystals, easily identified with the naked eye or with a hand lens, are pretty common, in my […]
I'll be mixing in photos from three different trips to Quartzville over the last couple years for this portion of the series; this one is from the middle of June, and shows a bit of vesicular basalt. The gas bubbles are partly filled with (mostly) stilbite. Note that I can't make that identification from this photo; the resolution isn't good enough. You need to get up close and personal with a hand lens to make that call. With the exception of natrolite, that's generally the case at this […]
Just plain-ole basalt. Dull, right? Well, yes, it can get tedious in a state so well endowed with that rock, but it can be interesting if there's something more than just plain-ole black ugly rock. In this case, the white splotches down lower are mostly Queen Anne's Lace. But the speckles up higher are calcite and zeolites, and those are pretty and interesting. The best way to look for them here is by splitting the cobbles and boulders that have fallen off the face and into the ditch/berm. The […]
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