painshill Posted January 22, 2012 Share Posted January 22, 2012 Here's a couple of nice ones. Olivine volcanic lava bomb (it has been cut and polished) from Hawaii: Volcanic pumice with fire opal from Mexico: Painshill 1 Roger I keep six honest serving-men (they taught me all I knew);Their names are What and Why and When and How and Where and Who [Rudyard Kipling] Link to comment Share on other sites More sharing options...
bdevey Posted January 26, 2012 Author Share Posted January 26, 2012 Today I received another interesting lava specimen collected on private land just outside of the Craters of the Moon National Monument along the Snake River Plain in southern Idaho. This type of lava specimen is called blue-glassy or Blue Dragon pahoehoe. The blue-glassy lobes form 10-14 days after the base of inflation and 5-10 °C cooler than adjacent silvery lobes of pahoehoe. Other distinct differences are a dense crystalline interior and fluorine-deficient surface that indicate blue-glassy pahoehoe was stagnant for a considerable period within the lava tube system allowing vapors to separate before extrusion. Also attached is page of different lava examples from my COTM souvenir book. Next I'm hoping for a bread-crust or spindle BOMB I've collected basaltic cinder in, blues, greens, golds and so on. All in the same pile, close to the vent that sent them shooting through the air. It's amazing the colors that are produced, depending on there temp, and how high they were sent in the air [cooling rate]. But I never thought about the low oxygen environment in a tube, hmmm Link to comment Share on other sites More sharing options...
bdevey Posted January 26, 2012 Author Share Posted January 26, 2012 Speeking of low oxygen, for fun, here's one from the moon. web site and a Quote.........".Lava from the lunar "seas". "This chunk of bubble-rich lava, collected by the Apollo 15 astronauts, typifies the surface rock of the dark maria (or "seas') on the Moon. Tremendous volcanic eruptions about 3.5 billion years ago flooded much of the Moon with molten lava resembling the volcanic rocks found in Hawaii and Iceland. Unlike Earth rocks, the lunar specimens contain no water; the nature of the gas that made the bubbles remains a mystery"......... Link to comment Share on other sites More sharing options...
Kosmoceras Posted February 12, 2012 Share Posted February 12, 2012 It counts, lets see it......That reminds me, recently a dam was taken out that was up river from me, and now I've seen a couple pieces floating down river. Sorry they are a bit late.... here is some.... Link to comment Share on other sites More sharing options...
dudeman Posted February 12, 2012 Share Posted February 12, 2012 Hey Auspex, just got a text from my Bud who looking after things for us. He said " I used a small amount of vinegar on the backside, did not see any reaction, I think? Not sure what I am looking for?" So, I'm not sure what this tells you, but there it is. P.S. Really nice lava everyone! Hey Auspex, I'm back home from Texas. If you still have questions? Troy Nelson Link to comment Share on other sites More sharing options...
Auspex Posted February 12, 2012 Share Posted February 12, 2012 Hey Auspex, I'm back home from Texas. If you still have questions? I was, with the vinegar thing, looking to see whether it was limestone (which it resembles in the pics). I guess it's not, with no reaction. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
dudeman Posted February 12, 2012 Share Posted February 12, 2012 I tried the vinegar when I got back, just too see for myself and I too saw no reaction. I does not look like Limestone (at least the limestone I'm use too, tan in color) in person, this piece is gray in color. Maybe Limestone from Peru is Gray in color? I have no idea... Troy Nelson Link to comment Share on other sites More sharing options...
piranha Posted March 21, 2012 Share Posted March 21, 2012 Here is another intriguing specimen for this great thread. This is actually a two for one special as a Volcanic Ventifact. One of the volcanologists at UO evaluated the composition and confirms it to be a dense mafic-intrusive that cooled slowly within the magma column. Once it became exposed at the surface wind erosion and sand-blasting etched the two distinct facets which designates this as a Zweikanter meaning a two-faceted ventifact. Other types are Einkanter (one) and Dreikanter (three) that are typically pyramidal in appearance. Stable ventifact formations, not subjected to movement, in conjunction with confident dating methodology can be utilized as paleo-wind indicators to interpret the differences in prevailing winds over time. Paleovolcanology is fun scale 1:1 = actual size of photo Link to comment Share on other sites More sharing options...
bdevey Posted March 28, 2012 Author Share Posted March 28, 2012 (edited) Paleovolcanology is fun I totally agree , Paleoseismology and paleogeography are also interesting. Though it makes me feel Paleo, because I remember when it all was geology. Bob Edited March 28, 2012 by bdevey Link to comment Share on other sites More sharing options...
piranha Posted April 9, 2012 Share Posted April 9, 2012 The following specimens are sure to please the hardcore volcanology enthusiasts. Finally was fortunate to find a couple of classic volcanic bombs (ejecta). The first one is the elusive breadcrust bomb and named for the cracked upper surface that is a solid cooled outer shell in flight but is shattered as hot gasses continued to expand within or upon impact. The next one is a textbook fusiform (spindle) bomb characterized by the elongate and streamlined aspect as formed and solidified in-flight orientation. The spindle also has an explosion feature: the hole shown in spindle photo 1 represents a hollow chamber where hot gas inside the bomb blasted out... perhaps upon impact photo scale = actual size These really are... Da' Bomb Link to comment Share on other sites More sharing options...
Auspex Posted April 9, 2012 Share Posted April 9, 2012 Excellent specimens, Scott And, your explanation is real value-added! "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Paleoc Posted April 10, 2012 Share Posted April 10, 2012 Kimberlite from the Arkansas Crater of Diamonds. Link to comment Share on other sites More sharing options...
AzMin Posted April 27, 2012 Share Posted April 27, 2012 Here are a couple of spindle bombs from flagstaff, AZ. One is fairly large and the other has a piece of Sunstone embedded in its surface. Link to comment Share on other sites More sharing options...
bdevey Posted May 8, 2012 Author Share Posted May 8, 2012 Dang, those are cool you guys! I sure would like a chance to go hunting for a bomb this summer, But Life has thrown me some curve balls lately that have kept me busy, but I'm missing the hunt I love the kimberlite paleoc. I have recently heard of a diamond find some were [unknown] , and have been studying the area for a hunt. But I hope to at least find some Kimberlite. Bob Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now