Fossils, geology and minerals. Highly acclaimed international earth science blog with over 850 articles and book reviews.
Jon Trevelyan (UK) This is the sixth of my series of short articles on fossils of the Ediacaran Period Fractofusus is one of the most abundant and ecologically revealing organisms of the Ediacaran Period, flourishing around 565 million years ago in the deep-marine settings of the Mistaken Point Formation, Newfoundland. … Read More
Jon Trevelyan (UK) This is the first of my series of short articles on fossils of the Ediacaran Period. Charnia is one of the most iconic fossils of the Ediacaran Period, known for its elegant frond-like form and its place among the earliest large, complex organisms in Earth’s history. First … Read More
Kurt Lahmers (USA) A closer look at a dinosaur bone found in the Garden Park area of Cañon City, Colorado (USA) shows some interesting details on the end of the bone. The holes in the dinosaur bone shownin Fig. 1 used to be tube-like structures called Haversian canals. These are … Read More
Jon Trevelyan (UK) This is the first of my series of short articles on fossils of the Pre-Cambrian. The Gunflint stromatolites, preserved in the 1.88-billion-year-old Gunflint Iron Formation of Ontario and Minnesota, offer one of the clearest windows into early complex microbial ecosystems. Formed by thriving mats of cyanobacteria long … Read More
Wayne W Sukow PhD and David L Schuder BA (USA) This is the last of three articles on the beaches of Sedar Bay. The first largely covered the geology of the area, the second discussed collecting minerals from the region, whereas this will cover the collection of fossils. Fossils from … Read More
Wayne W Sukow PhD and David L Schuder BA (USA) This is the second of three articles on the beaches of Sedar Bay. The first largely covered the geology of the area. This article will discuss collecting from the region. Collecting Sedar Bay agates, minerals and fossils The collection of … Read More
Wayne W Sukow PhD and David L Schuder BA (USA) This is the first of three articles about the Upper Peninsula of Michigan. Here, there are many miles of Lake Superior shoreline, but the three articles will just cover the Keweenaw Peninsula, where you can find agates, copper, silver, datolite, … Read More
Zachary Sepulveda (USA) The subject matter of this short article is a rare, agatised snail fossil from the Jurassic Period, which was found in the Morrison Formation, and a dinosaur bone of an unknown species from the same layers. Both specimens are from Colorado. The Morrison Formation is a sequence … Read More
Steven Wade Veatch (USA) Along the Front Range of Colorado, there are more than 200 sandstone dikes emplaced in ancient igneous (crystalline) rocks. Dikes are rock bodies that cut across another, earlier geologic body. These Front Range dikes are unique, because most sandstone dikes are found in other sedimentary rocks. … Read More
Denis Bates and Anna Kozłowska (Poland) Graptolites (grapto + lithos = writing in the rocks) are common Palaeozoic fossils – found from the Cambrian to the Carboniferous. Usually, they are preserved as flattened and altered remains in mudrocks, particularly the black shales or slates known as “Graptolitic Shales” (Fig. 1), … Read More
Wayne Sukow (USA) Found in situ at the Wolverine #2 Mine in Houghton County, MI is a rare and unique Lake Superior agate. Some of those recovered are infused with varying amounts of massive copper, ranging from flecks visible to the unaided eye to solid stretches of native copper. Some … Read More
Steve Koppes (USA) When the solar system was born 4.5 billion years ago, davisite and grossmanite were soon there. These minerals were two of the first solids to form when an interstellar gas cloud collapsed to form the sun. Found in the Allende meteorite (Fig. 1), they now carry the … Read More
Deborah Painter (USA) Why is there a reef in a cavern under a hill in south-central Pennsylvania in the USA? My good friends Richard Hedges and David Hawk and I wanted to know the answer. We had seen various websites which describe an amazing commercial cave with one wall composed … Read More
Mike Viney (USA) Introduction The Front Range of the Colorado Rockies is not a place one would expect to find a residence designed in the style of a European castle. So, for me, it was a delightful surprise to learn about the existence of Cherokee Castle in Sedalia, Colorado (Fig. … Read More
Wayne Sukow (USA) In Part 1 of this article, I showed how agate begins to form. Starting with tiny bubbles on the surface of a cavity in basalt, a husk forms showing their imprints. These bubbles are implicated in the creation of amorphous silica aggregates. There is also a steady … Read More
Today (14 December 2024), we start a four-part series on the geology and chemistry of Lake Superior agates, by Dr Wayne Sukow (USA), who these days is a retired physicist from the National Science Foundation in the USA. Wayner wrote these articles a while ago for us, and provided some … Read More
Steven Wade Veatch (USA) Hidden among geological marvels at a mineral show was a cinnabar-bearing chalcedony breccia-specimen (Fig. 1). The term “breccia” refers to a rock composed of angular fragments, while “chalcedony” describes a type of cryptocrystalline quartz. Adding “cinnabar” specifies the presence of mercury sulphide, which creates a distinctive … Read More
Deborah Painter (USA) The famed English explorer of the “New World”, Captain John Smith, led expeditions during the early 1600s to create charts and plan settlements along the east coast of the United States, from what is now Virginia to Maryland and, on a subsequent voyage, New England. Smith’s map … Read More
Chris Retzlaff (USA) The Redhill Ridge area in Park County, Colorado is a hogback composed of Dakota Sandstone. This fine-grained, Cretaceous sediment – near the town of Fairplay – contains trace fossils (Figs. 1 and 2) that help palaeontologists understand what the environment was like there, more than 65 million … Read More
