Napoleon North Posted September 28, 2017 Share Posted September 28, 2017 Hi It is ichthyosaurus bone piece ? Location: Vistula river area , Pychowice , Kraków ,Southern Poland Age: Jurassic? Link to comment Share on other sites More sharing options...
Fossildude19 Posted September 28, 2017 Share Posted September 28, 2017 I don't think so. Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Napoleon North Posted September 28, 2017 Author Share Posted September 28, 2017 Next photo. Link to comment Share on other sites More sharing options...
jpc Posted September 28, 2017 Share Posted September 28, 2017 Hard to say if it is bone or not, nevermind what animal it might be from. I see no bony texture, but then the pix are pretty small. Link to comment Share on other sites More sharing options...
FossilDAWG Posted September 28, 2017 Share Posted September 28, 2017 I don't think it has a "bone" texture. At any rate such a small fragment could not be identified with any confidence, as no diagnostic features are present. Don Link to comment Share on other sites More sharing options...
abyssunder Posted September 30, 2017 Share Posted September 30, 2017 Maybe fibrous calcite veins with a dark median zone. " Field, petrographic and geochemical analysis of fibrous calcite veins in the Lower Jurassic Shales-with-Beef Member in the Wessex Basin was conducted to investigate the formation mechanism of the veins. Bedding-parallel fibrous calcite veins, including beef veins and tabular cone-in-cone structures, are widespread in the black shales. The calcite veins consist of subvertical fibrous crystals and a dark median zone. The median zone contains scattered clays, pyrite microcrystals, skeletal fragments and amorphous organic matter. The veins exhibit moderate carbon isotope values, ranging from −1.515 to 2.732‰. The oxygen isotope composition ranges from −8.872 to −4.521‰, which is possibly too negative to reflect the primary porewater oxygen isotope signatures and indicates a porewater modification. It is interpreted that the veins mainly derive carbonates from seawater inorganic carbon and bioclasts. The veins formed as closed-system hydraulic fractures in overpressured cells during sediment degassing in the methanogenic zone. The shale beds with a high total organic carbon content could have generated abundant CO2, which may have resulted in either the cementing of the pores in the matrix or overpressure buildup. The skeletal fragments provide a control on the spatial distribution of veins as nuclei for calcite precipitation from supersaturated pore fluids. " - Q. Meng et al. 2017. Early overpressuring in organic-rich shales during burial: Evidence from fibrous calcite veins in the Lower Jurassic Shales-with-Beef Member in the Wessex Basin, UK. Journal of the Geological Society. 174. 869-882 " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
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