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Ya had me there for a sec!karstcreature wrote:So staining events usually occur separately from initial deposition?
all those formations I chopped were the same color throughout...
HAHA just kidding...thanks for the response...
I *assumed* when you wrote "dyeing to appear igneous" you meant staining on the outside. That's why I wrote my answer the way I did.karstcreature wrote:I'm wondering if some drippy-looking formations in lava tubes could actually be calcareous but through mineral leaching/dyeing actually appear to be of the same igneous rock as the cave(tube) itself
David_Weaver wrote:Lava tubes can also contain solution formations, similar to those we see in limestone/marble caves. These formations originate the same as in carbonate caves. Groundwater dissolves the minerals, carries them into the cave, and precipitates the minerals when the water evaporates. The bedrock around lava tubes contains different minerals than the limestone and marble bedrock surrounding carbonate caves. Consequently, the minerals are different and the formations appear different. The minerals tend to be more silicate based than carbonate based. (Think Opal) Aluminum is also a typical component of these minerals.
Squirrel Girl wrote:
karstcreature wrote:
why do we rarely ever see calcite formations in lava tubes anyway??
thanks
knotty wrote:What causes the different colors in lava? Some of the caves here in Idaho have as many as 7 different colors(7 different flows). Eache flow has there own color. The color is brightes on the surface or glaze but there is color all through the porus section as well.
Initially these eruptions are very violent and produce a lava known as rhyolite. Huge calderas of up to 30 miles in diameter are formed when these devastating eruptions take place. Later a more fluid lava known as basalt flows onto the surface and covers the rhyolitic flows. Yellowstone National Park, the area where the hot spot is believed to be located at this time, is the place where catastrophic rhyolitic eruptions last occurred 600,000 years ago. Craters of the Moon represents the second stage of the eruptions where fluid basaltic lava covered the landscape as recently as 2,000 years ago.
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