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What an awesome rock, there is also three plaques on it dedicated to people who lost their lives , Two were a couple of guys that used to surf here, I am not 100% sure but I think they died in the "Bali bombings"., The other two plaques were for two ladies that died by accident, probably on the beach or drowned..
Juan Vasquez and Gilbert O'Reilly used to mine this area in the 1820's. They were terrible miners and barely made enough to put sagebrush over their heads. So, they decided to start a food wagon business and cater to the other miners. It turned out to be a brilliant idea. When the mining activity died down a few years later, they moved to the Los Angeles area. Their business skyrocketed. After Juan and Gilbert passed on, the business was taken over by family members and continues to prosper. Today you can find their food trucks all over Southern California.
(the above is a fictitious account except for the part about food trucks all over Southern California)
Red Rock State Park, Kern County, California 2015
Age: 150-160Ma
Oxfordian to Kimmeridgian Age
Late Jurassic Epoch
Jurassic Period
Mesozoic Era - Dinosaur times
Location: Yorkshire Coast
Filey Bay
Reighton
Rock Type: Mudstone likely of Ampthill or Kimmeridge Clay Formations
Specimen:
An amphicoelous (both anterior and posterior sides are concave) vertebral body. Such vertebrae are adapted to allow for a degree of flexibility and articulation that is particularly beneficial in an aquatic environment. This structural adaptation helps to streamline the body and facilitate efficient, undulating movements through water. Amphicolous vertebrae have therefore convergently evolved multiple times, such as in both fish and marine reptiles. This is from a plesiosaur according to a visit to Manchester Museum due to the more angular, almost triangular shape, rather than more rounded and coin-like such as in ichthyosaurs apparently. Also generally thicker than a thin ichthyosaur vertebrae.
Species:
Plesiosauroidea (from Greek plēsios, meaning 'near' or 'close to', and sauros, meaning 'lizard') is an extinct clade of carnivorous marine reptiles. They are notable for having the longest neck-to-body ratio of any reptile, with their snake-like necks being a defining feature. Plesiosauroids lived during the Jurassic and Cretaceous periods, first appearing in the Early Jurassic (late Sinemurian stage) and thriving until the mass extinction event at the end of the Cretaceous Period (K-Pg extinction). Although they coexisted with dinosaurs in the Mesozoic era, plesiosauroids were not dinosaurs but rather diapsid reptiles.
The first complete plesiosauroid skeletons were discovered in England by Mary Anning in the early 19th century, making them some of the earliest fossil vertebrates described by science. Plesiosauroids had broad bodies, short tails, and retained two pairs of limbs that evolved into large flippers, which were key to their marine lifestyle. Fossil evidence also frequently includes gastroliths (gut stones), which were likely used to aid digestion or balance in the water.
Recent studies of their teeth have suggested that plesiosauroids, along with other marine reptiles, had a warm-blooded (endothermic) metabolism similar to that of mammals, allowing them to survive in colder waters. Unlike their faster-swimming relatives, the pliosaurs, most plesiosauroids (except for members of the Polycotylidae family) were likely slow swimmers. It is believed they cruised beneath the surface of the water, using their long necks to snap up fish and cephalopods. Their four-flipper swimming adaptation gave them exceptional maneuverability, allowing them to rotate and change direction quickly to catch prey.
Contrary to many artistic reconstructions, plesiosauroids could not lift their heads and necks above the water in a swan-like pose. Even if their necks had the flexibility for such a movement (which they did not), the weight of their neck would have caused their bodies to tip forward, keeping most of the neck submerged.
One significant discovery related to plesiosaur reproduction was made on 12 August 2011, when U.S. researchers described a fossil of a pregnant plesiosaur (Polycotylus latippinus) found in Kansas. This fossil confirmed that plesiosauroids gave birth to a single, large live offspring, contrasting with other marine reptiles that typically gave birth to multiple smaller young. This finding also dispelled previous theories suggesting plesiosauroids crawled onto land to lay eggs, as their anatomy made terrestrial movement unlikely.
Plesiosauroids varied in size depending on the species. Adult individuals, such as those known from near Yorkshire, typically ranged from 3 to 7 meters in length.
Reptiles, as traditionally defined, are a group of tetrapods that typically have ectothermic ('cold-blooded') metabolisms and develop through amniotic eggs. However, modern taxonomy, based on genetic and paleontological evidence, considers reptiles a paraphyletic group. This is because birds (class Aves), which evolved from dinosaurs, are more closely related to crocodilians than to other reptiles. Therefore, birds are often included within the reptilian group in many cladistic systems, redefining Reptilia as a monophyletic clade that includes both birds and reptiles. The exact definition of this clade varies among scientists, with some preferring the term Sauropsida to encompass all amniotes more closely related to reptiles than to mammals.
The earliest proto-reptiles appeared in the Carboniferous period, evolving from reptiliomorph tetrapods that were increasingly adapted to life on land. In addition to modern reptiles, there were many now-extinct groups, some of which disappeared during mass extinction events, such as the Cretaceous–Paleogene extinction. This event wiped out pterosaurs, plesiosaurs, and all non-avian dinosaurs, along with many species of crocodilians and squamates like mosasaurs. Reptiles are tetrapod vertebrates, meaning they either have four limbs or descended from ancestors that did. Unlike amphibians, reptiles do not undergo an aquatic larval stage. Most are oviparous (egg-laying), but some squamates are viviparous, with embryos developing inside the mother, nourished by a placenta rather than enclosed in eggshells.
As amniotes, reptile eggs are protected by membranes, enabling reproduction on dry land. Some viviparous reptiles have placentas analogous to those of mammals and provide initial care to their young. The earliest amniotes, including stem-reptiles, were relatively small and inconspicuous compared to larger tetrapods like Cochleosaurus. However, during the Carboniferous Rainforest Collapse, primitive tetrapods were devastated, while stem-reptiles thrived in the drier conditions. Unlike amphibians, which required water for reproduction, early reptiles could lay their shelled eggs on land, giving them an advantage in the new environment. As a result, amniotes rapidly diversified, adopting new feeding strategies, including herbivory and carnivory, and outcompeting primitive tetrapods.
The dominance of reptiles in terrestrial ecosystems set the stage for the Mesozoic era, also known as the 'Age of Reptiles'. A 2021 study of reptile diversity during the Carboniferous and Permian periods revealed a higher level of diversity than previously thought, comparable to or even exceeding that of synapsids. This period has been proposed as the 'First Age of Reptiles.' The Permian–Triassic extinction event, the most significant mass extinction in Earth's history, caused a prolonged die-off, eliminating most of the earlier parareptile and synapsid megafauna. True reptiles, particularly archosauromorphs, survived and thrived, characterized by elongated hind legs and an upright posture. These early archosaurs eventually gave rise to the dinosaurs and pterosaurs, as well as the ancestors of modern crocodiles.
During the Triassic period, archosaurs became the dominant group, evolving into the dinosaurs and smaller theropods, which later gave rise to birds. The sister group to archosaurs is Lepidosauromorpha, which includes lizards, tuataras, and their fossil relatives. Mosasaurs, one of the major groups of Mesozoic marine reptiles, belong to this clade. Other marine reptiles, such as ichthyosaurs and sauropterygians, evolved during the early Triassic, but their exact phylogenetic placement remains debated. Some researchers link them to lepidosauromorphs, while others associate them with archosauromorphs or classify them as diapsids outside these two groups.
The close of the Cretaceous period saw the extinction of many Mesozoic reptilian megafauna during the Cretaceous–Paleogene extinction event. Large marine reptiles, except for sea turtles, perished, and only semi-aquatic crocodiles and the lizard-like choristoderes, which later became extinct in the Miocene, survived. Of the dinosaurs, only small beaked birds survived this mass extinction, which marked the end of the Mesozoic and the rise of the Cenozoic era. In the aftermath, mammals and birds rapidly diversified, filling the ecological niches left by extinct reptiles. While reptile diversification slowed, they remained key components of the megafauna, especially in the form of large tortoises. Though mammals and birds came to
Age: 343-337Ma
Viséan
Middle Mississippian Epoch
Carboniferous Period - Giant arthropods and amphibians, early reptiles, most plants fern or lycophyte-like, known for tropical forests and seas
Paleozoic Era - pre-Dinosaurs
Location: England
Lancashire
Hurst Green (Stonyhurst)
Dinckley
Dinckley Hall
The brook east of Dinckley Bridge
Rock Type: Bowland Shale Formation mudstone.
Specimen:
A goniatite about 3cm in diameter. Slight shell ridging can be seen. Very crushed and flattened in the shale.
Species:
Goniatites is a genus of extinct ammonoid cephalopods that lived from the Devonian to the Permian periods, roughly 390 to 250 million years ago. The genus belongs to the order Goniatitida, which is characterised by its intricately folded, or lobed, suture lines along the shells. These marine animals had coiled, chambered shells that served as buoyancy aids, allowing them to move vertically within the water column.
The name Goniatites is derived from the Greek word "gonia," meaning "angle," referring to the angular lobes in their suture patterns. This suture design differentiates them from later ammonoids like ceratites and ammonites, which have more complex sutures. As with all ammonoids, the animal resided in the outermost chamber of its shell, while the inner chambers were filled with gas or fluid to control buoyancy.
The shell of Goniatites was generally smooth or only slightly ribbed, and its size varied widely depending on the species, with some reaching several centimetres in diameter. Like other ammonoids, Goniatites is believed to have been an active predator, feeding on small marine organisms such as crustaceans and plankton.
Fossils of Goniatites are commonly found in marine sediments across the world, especially in areas that were once part of shallow seas. Their wide geographic distribution and distinctive suture patterns make them valuable index fossils for dating Palaeozoic rocks. The extinction of Goniatites occurred during the Permian mass extinction, marking the end of this genus.
Ammonoids are an extinct group of spiral-shelled cephalopods belonging to the subclass Ammonoidea, more closely related to modern coleoids (octopuses, squids, and cuttlefish) than to shelled nautiloids like Nautilus. They first appeared during the Devonian period (around 409 million years ago) and went extinct shortly after the Cretaceous-Paleogene extinction event (66 million years ago). Originating from bactritoid nautiloids, ammonoids are commonly referred to as "ammonites," although this term technically applies to the order Ammonitida, the last surviving group of ammonoids from the Jurassic until their extinction.
Ammonites are prized as index fossils, as their presence helps geologists link rock layers to specific time periods. Their fossilized shells typically appear as tightly coiled planispirals, but some variations, such as helically coiled or non-spiraled forms (heteromorphs), have been discovered.
The name "ammonite" derives from the spiral shape of their fossilized shells, which resemble coiled ram's horns. The term comes from Pliny the Elder, who called them "ammonis cornua" ("horns of Ammon") after the Egyptian god Ammon, often depicted with ram’s horns. Many ammonite genera have names ending in -ceras, from the Greek word "kéras" meaning "horn."
Ammonoids are distinguished from nautiloids by the structure of their septa, the walls dividing the chambers of their shells (phragmocone). Their suture lines—the intersection of septa with the outer shell—are more complex, featuring lobes and saddles. Three main suture patterns define ammonoids: Goniatitic – Characterized by undivided lobes and saddles, typical of Paleozoic ammonoids. Ceratitic – Lobes with subdivided tips (saw-toothed) and rounded saddles, common in Triassic ammonoids. Ammonitic – Highly subdivided lobes and saddles, found in Jurassic and Cretaceous ammonoids.
The soft body of ammonoids occupied the largest chamber at the end of the shell coil, while earlier chambers, filled with gas, aided in buoyancy. A tube called the siphuncle connected these chambers, allowing the ammonoid to regulate buoyancy by emptying water from the chambers through osmotic processes. Their shells were generally planispiral, with varying degrees of overlap between the whorls. This degree of overlap is reflected in two main shell types: Involute shells (e.g., Anahoplites) have outer whorls that largely cover earlier whorls. Evolute shells (e.g., Dactylioceras) have minimal overlap, with a large umbilicus exposing earlier whorls.
Ammonoids exhibited various shell forms, each suggesting different lifestyles and levels of hydrodynamic efficiency. Some major forms include: Oxycone – Narrow, involute shells with sharp keels, adapted for rapid swimming. Serpenticone – Evolute, discoidal shells; flattened for efficient acceleration, likely planktonic or nektonic. Spherocone – Broad, globular shells, suited for vertical migration in the water column. Platycone and Discocone – Intermediate forms between oxycones, spherocones, and serpenticones.
These shapes likely influenced how ammonoids swam, with some species (such as Oxynoticeras) thought to have been efficient swimmers, while others were slower bottom-dwellers.
Ammonoids likely lived in the upper 250 meters of the water column and are often found in rocks deposited in open-water conditions. Fossil evidence suggests they may have fed on plankton, with some ammonites showing remains of small molluscs and isopod larvae in their buccal cavities. Like modern cephalopods, ammonoids may have defended themselves by ejecting ink, a feature occasionally preserved in fossil specimens.
The chambered structure of ammonite shells, known as the phragmocone, consisted of progressively larger chambers (camerae) divided by septa. The living animal occupied the last chamber, continuously adding new chambers as it grew. This chambered design helped maintain buoyancy and control movement within the water column. Ammonites with shells that diverged from the typical planispiral shape are known as heteromorphs, featuring more open or non-spiral coiling.
In medieval Europe, ammonite fossils were believed to be petrified snakes, known as "snakestones" or "serpentstones," often associated with legends of saints such as St. Hilda of Whitby and St. Patrick. Traders would sometimes carve or paint snake heads on the fossils to enhance their resemblance to snakes, selling them as objects of mythological or healing significance.
Group sitting on concretions while geologist Sparky Wilson lectures at the Pumpkin Patch in Anza-Borrego Desert State Park, circa 1960s.
Photographer: Unknown
Donor: Louise Gorin
Original: Color print. Original returned to Louise Gorin after scanning.
Credit: James & Louise Gorin Collection, Sierra Club-Angeles Chapter Archives
Image ID (file name): Gorin 025
NO KNOWN COPYRIGHT RESTRICTIONS:
By asserting "no known copyright restrictions," the SIERRA CLUB ANGELES CHAPTER HISTORY COMMITTEE is sharing the benefit of our research without providing an expressed or implied warranty to others who would like to use or reproduce the photograph. This means that we are unaware of any current copyright restrictions on the works so designated, either because the term of copyright may have expired without being renewed, because no evidence has been found that copyright restrictions apply, because the original creator has granted us permission to post the image on the Internet, or because we own the copyright but are not exercising that control. The HISTORY COMMITTEE cannot guarantee that private or commercial use of the images shared herein will not violate the rights of unidentified copyright holders and we cannot be responsible for any liability resulting from the use of these images.
If you make use of a photo from this source, you are reminded to conduct an independent analysis of applicable law before proceeding with a particular new use.
Whilst the Blue John Cavern is a natural cave, parts of it have been altered by man. With mining the Blue John
The Pizzi Bianchi (White Peaks) which overlook the south coast of Ischia. The peaks are made of white tufa, eroded and sculpted over centuries by the weather.
The Pizzi Bianchi (White Peaks) which overlook the south coast of Ischia. The peaks are made of white tufa, eroded and sculpted over centuries by the weather.
Group sitting on concretions while geologist Sparky Wilson lectures at the Pumpkin Patch in Anza-Borrego Desert State Park, circa 1960s.
Photographer: Unknown
Donor: Louise Gorin
Original: Color print. Original returned to Louise Gorin after scanning.
Credit: James & Louise Gorin Collection, Sierra Club-Angeles Chapter Archives
Image ID (file name): Gorin 026
NO KNOWN COPYRIGHT RESTRICTIONS:
By asserting "no known copyright restrictions," the SIERRA CLUB ANGELES CHAPTER HISTORY COMMITTEE is sharing the benefit of our research without providing an expressed or implied warranty to others who would like to use or reproduce the photograph. This means that we are unaware of any current copyright restrictions on the works so designated, either because the term of copyright may have expired without being renewed, because no evidence has been found that copyright restrictions apply, because the original creator has granted us permission to post the image on the Internet, or because we own the copyright but are not exercising that control. The HISTORY COMMITTEE cannot guarantee that private or commercial use of the images shared herein will not violate the rights of unidentified copyright holders and we cannot be responsible for any liability resulting from the use of these images.
If you make use of a photo from this source, you are reminded to conduct an independent analysis of applicable law before proceeding with a particular new use.