![]() ![]() ![]() It splashed down approximately 29 hours later off the coast of Florida, USA. 3, 2020)Īstronauts aboard the International Space Station farewelled over 2000 kg of scientific experiments and hardware on Sunday 23 January as a cargo Dragon spacecraft began its return to Earth.ĮSA astronaut Matthias Maurer captured the resupply vehicle in all its glory as it departed the orbital outpost at 15:40 GMT/16:40 CET. sandstone" and "Field geology: bedrock exposures" albums. See other examples of geological details in my "Paskapoo Fm. sandstone and shale) were deposited in and around rivers (in river channels, and on the floodplains adjacent to the main river channels) in what is now southern Alberta, and unsurprisingly, plants would have grown on the floodplain (overbank) areas, just as they do near rivers today. Back in Early Tertiary time, sand and mud (later lithified into Paskapoo Fm. 60 million years old) that has been used as building stone at a site in south Calgary. This view of sedimentary geological details is from a boulder of Paskapoo Formation sandstone (Early Tertiary age: ca. To recognize such subtle details, it helps to have the 'expert eye' of a clastic sedimentologist, a type of geologist that specializes in this sort of thing. The original sedimentary bedding (flat to low-angle layering) is faintly visible in a few spots: near the upper left and lower right corners of the view, low-angle laminations (sloping down to the left) in the sandstone are the internal micro-layering of preserved ripple structures. Preservation of the root structures is patchy and irregular in some places. Some of the root structures show downward branching: inverted V shapes or inverted Y shapes (the 'wishbone' shape near the upper right corner is the best-defined example of this). The reddish-brown (oxidized, rusty) vertical linear structures are the fossilized impressions (casts, traces) of plant roots that grew downward into sandy soil (later buried and lithified into sandstone). ![]() This photo shows a cross-sectional view (a roughly planar surface perpendicular to the originally flat sedimentary bedding/layering). ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |