Geology Today最新文献

In 2023, two decades after the restoration of the Victorian Geological Illustrations by the London Borough of Bromley—and the visit of the late HRH Prince Phillip to mark the completion of the restorations—it is clear that these internationally significant sculptures are in a worse state than ever before. Although interest in them remains high, and in spite of the best efforts of the Friends of the Crystal Palace Dinosaurs to protect and interpret them, it is plain that they are greatly at risk. In the year that marks the two-hundredth anniversary of the description of Megalosaurus, depicted in all its magnificence in the park, it is a matter of urgency that we promote the significance of a site that really should be recognized for what it is—world heritage—and its current state of neglect.

Many rock and mineral collectors have roots in the movies and books of Jules Verne, such as Journey to the Centre of the Earth (1864). It seems only fitting that the mineral verneite was recently named after him, one of only three writers (Verne, Goethe and Theophrastus) to have a mineral named after them. Verne was an active amateur geologist, visiting sites throughout Europe. Of Verne's 80 novels, many have geological themes, subthemes or backgrounds second only to the sea. Like in his Journey to the Center of the Earth, Verne's lesser geological novels offer a remarkable literary guide to rocks, minerals and geology. Verne's geology-based novels and writings are extensive and provide a means to re-energize your childhood love of mineral collecting.

Syenites are felsic plutonic igneous rocks characterized by the lack of quartz (<5 percent) or feldspathoids (<10 percent), although quartz syenites have 5–20 percent quartz. Typically they consist of feldspars, predominantly alkali feldspar with minor ferromagnesian minerals, usually pyroxene, amphibole or biotite. Syenites are overwhelmingly rocks of extensional environments and generally occur in areas of continental rifting, such as the African Rift Valley, and also on oceanic islands, such as the Canary archipelago. The extrusive equivalent of syenite is trachyte. As examples, we will look at two plutonic complexes containing syenites: the little-known Kangerlussuaq intrusion in East Greenland and the more familiar Larvik Plutonic Complex in the Oslo region of Norway. Syenites occur in association with both oversaturated (quartz syenites and granites) and foid-bearing rocks (typically nepheline syenites). Agpaitic syenites are highly evolved types with titano-zircono-silicates such as eudialyte. Syenites find use as dimension stones and countertops.

We are living in the midst of a great technological revolution in history—the energy transition from today's fossil fuel-dominated civilization to low-carbon economies and industries. Geoscientists will significantly contribute to energy science, policy and technologies by advancing our knowledge base of the complex interacting processes and substances in Earth's lithosphere, oceans and atmosphere. Mapping the flow of energy in various forms and intensities in Earth systems, exploration of energy resources and minerals and evaluating the environmental impacts of energy technologies from upstream to downstream will be increasingly embedded in geoscience education, research and workforce development. This article outlines major pathways of how geoscience will contribute to various components of the energy transition.

New academic journals come, but some old journals have gone, sad to say. Four contrasting journals that blossomed since the mid-1950s and subsequently vanished are discussed here. The demise of these journals is linked to failing enthusiasm of one form or another, by subscribers, publishers or contributors. Money was often an issue. All were worthy and would form a valid part of the modern diversity of geological publications if only they had survived.

The beauty of an eclogite is something to behold: any petrologist marvels in the combination of red garnet and green omphacite that are the main mineral constituents of the rock. But besides their stunning appearance, there is much more to eclogites: fundamental concepts in metamorphic petrology and geodynamics were developed based on scientific investigations of eclogites. It is well established that they derive from precursor rocks of basaltic composition and form under high-pressure conditions at more than c. 45 km depth, but other aspects of their occurrences and geological significance remain debated. The relative scarcity of eclogites among crustal rocks renders them largely unknown to the layperson, so following the 200th anniversary of the term eclogite in 2022, there is an opportunity to take a closer look at this fascinating rock.

The Jurassic strata running through the county of Buckinghamshire, English south midlands, culminate in the marine to non-marine Upper Tithonian (formerly Portlandian) Portland and Purbeck formations. Despite poor exposure, this richly fossiliferous and strongly regressive carbonate-clastic succession allows reconstruction of shallow marine, coastal lagoonal and ultimately lacustrine environments, against the backdrop of a hot, greenhouse climate.

By the end of the nineteenth century, biostratigraphy had come to be thought of as a matter of induced extinctions, of varying severity, subsequent to which some surviving species would go on to generate forms adapted to the changed Earth environment. John Phillips', proposal from 1841, that the systems comprising the biostratigraphical record could be packaged into three eras—Palaeozoic, Mesozoic and Cenozoic—recognized that the end Permian and end Cretaceous were defined by extinctions that globally eliminated a large proportion of the previously abundant and long-lived terrestrial and marine taxa. These two key horizons are now seen as defining two of a series of at least five Phanerozoic global mass extinctions, each of which suggested a short-lived major disruption of the entire biosphere.