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The White Stairs This amazing site is a beach in southern Sicily known as Scala dei Turchi. It is a popular beach and tourist destination, both for the views and for the water, which is rich in sedimentary mud coming from the exposed outcrop.
Mid-Morning Shadows
Mesquite Sand Dunes, Death Valley
Stream gauging at the Colosseum The scientist up to his waist in Oregon’s Owyhee River is stream gauging. By measuring the depth of the river at a given point, the volume of water flowing through the river can be determined if you know some basic properties like the shape and width of the channel. The US Geological Survey posted this picture to, in part, slightly brag about the kind of settings geologists get to work in.
Slump folding This sequence of folded layers is a slump fold, formed when sediment falls on a slope and begins to move under the influence of gravity (or other similar stress).
Wind-induced ripple bedform with an obstacle (grass at the center) that resulted in shadow-like impressions by flow disturbance. Wind direction from lower left to upper right. On the coastal dunes along the shore of Niigata city.
風による堆積物の模様と草の障害物による流れの乱れの痕跡
Tidally dominated deltas This is a satellite photo of part of the Gulf of Papua captured by the USGS Landsat program in 1989. It shows two major river deltas – the large river on the western side is the Fly River and the river that splits into many channels in the center of the image is the Kikori River. Several other smaller stream channels sit in-between these two larger features.
Sawanna Łężycka (Łężyce Savanna also known as Łężyckie Rocks, Skałki Łężyckie) is the informal name of the terrain laying south of the Rogowa Kopa mountain (790 m a.s.l.), in the south-western part of the Stołowe (Table) Mountains. The most characteristic feature of the area are the scattered sandstone blocks in allochthonous position. Their origin is still unclear. More than 40 boulders can be found here, from the smallest 2–3 m long to massive ones up to 10 m long and 5–6 m high. They owe their survival to the massiveness of the ‘Upper Sandstone’ and its much higher resistance compared to easily erodible mudstone.
In the past, the sandstones of Sawanna Łężycka were used for the local purposes as an easy accessible material. A few blocks still show signs of such activity and it's very likely some may have disappeared completely.
Long Lakeshore I saw this map and couldn’t help but wonder if this lake would hold the record for highest ratio of “shoreline length to lake area” in all of geologic history.
The Landscape of Capitol Reef National Park. Gently dipping sedimentary rocks of the Waterpocket fold.
1.6 billion year old ripples. Stop and think about that headline for a second, isn’t it remarkable? The casts on the surface of this rock layer preserve patterns made by the ocean flowing over sediment nearly 2 billion years ago.
Fault Bend Fold Not every fault on the planet reaches the surface. In fact, most of them don’t. Many faults form at depths of several kilometers below the Earth’s surface and as they move, the rocks around them can be bent and folded without breaking.
How do we see if the pieces fit? This is a core of sediment taken from the northeastern portion of Australia’s Northern Territory. This area is filled with sedimentary rocks that formed in the latter half of the Precambrian, starting sometime around 1.5 billion years ago. At the time, this section of the planet was a deep basin that was slowly filling with sediments, something like the Gulf of Mexico today.
Confluence Look at this image and try to find the Rio Negro – my eyes actually skipped over it at first because of how incredibly dark it looks. At this spot in the rainforest of Brazil, the longest black water river in the world – the Rio Negro – comes together with the muddy Solimões River. The two waters run side by side for several kilometers before they fully mix as the Rio Negro is warmer and moving more slowly than the waters of the Solimões River, so for some distance the dark water floats on top.
The Umm Ishrin Formation The Umm Ishrin formation is a fascinating and famous geological unit, although it is likely most famous because of the way people have cut it. The ancient city of Petra in Jordan, a UNESCO World Heritage site visited by about a million people per year, is cut into this sandstone.
Stressed out trilobite This trilobite probably feels like an awful lot of us these days. It started off in its normal shape, discarded onto the ocean floor as the organism shed it. That little trilobite shell found its way into sediment and eventually became part of a rock. But then, something happened to that rock – it was put under stress, from the old sedimentary layer being pulled into a mountain building event. The stress was gentle enough that the rock didn’t break, but it was strong enough and lasted long enough that the rock started to gradually shift its shape. Our once normal looking trilobite began shearing and twisting under the strain, bending to the side and eventually taking the shape seen here.
