Academic literature on the topic 'Rocks in art'

Human representations are one of the most important groups of depictions in rock art in southern Scandinavia. These humans have long been discussed as complete, stable, and temporally-fixed images. The results of a new survey challenge this view. Recording rock art with Reflectance Transformation Imaging (RTI) enabled us to discern a possible sequence of production of individual human representations, their bodily features, and associated objects. Figures from a rock art site in Finntorp (Tanum, Sweden) will be used as an example. Differences in the dimensions of the engraved lines, the chronology of the depicted objects, and the placement of body parts suggest that several individuals may have been involved in making human representations on the rocks, and that their appearance as complete figures is the result of repeated transformations. The results presented demonstrate that Scandinavian rock art is not stable in time. We suggest that rock art is best understood as the creation of communities over time, which enables them to engage with the past by transforming the rocks.

AbstractThis paper is an addition to the recent advances in the field of rock art research and aims to accentuate the significance of rocks and boulders in the production of rock art. I argue that the rock itself must be recognized as an important element in rock art production even in cases where there are no discernible connections between the rock art images and the irregularities found in the rock surface. The paper concerns rock carvings from the Taru Thang site in Ladakh in northern India and builds on ethnography drawn from the Dardic-speaking people of the western Himalayas. I argue that the rocks must be understood as devices of communication between hunters and their supernatural allies, and that the images represent messages conveyed through the rock interface. In these acts of communication, the geological irregularities of the rock surface serve no purpose and have been avoided rather than included in the compositions.

This paper aims to discuss the impact and importance of the karstic caves, which are effective on the emergence and development of cave art and the rocks that generate them. The origin of cave traces to 40 thousand years and the creation of many more works of art and the importance of the rocks to the present day is very important. In particular, carbonate rocks such as limestone and marble became important spaces and raw materials in terms of art history and development. Carbonate deposits placed in the large ocean bowls during geological periods have been elevated and altered land during orogenesis periods. The fact that the carbonate rocks are soluble due to environmental conditions has led to the formation of a large number of caves depending on the size and distribution of the masses forming them. These karstic caves, which constitute a significant part of the caves in the world, have been the habitat of old people for almost 1-1.5 million years. The caves have been very important shelters for life, which became difficult due to the cold climatic conditions during the glacial periods, which were effective during the last 2 million years (Pleistocene). Under the challenging conditions of the Paleolithic period, human societies have tried to survive on the one hand and, on the other hand, achieved their symbolic thinking skills with their developing brain capacities 100,000 years ago. In the following period, the human communities that continued to develop have left very important ruins, which dates back to 40-10 thousand years ago and are regarded as works of art. Structural features of the caves and the rocks forming them are of great importance in the emergence of these works, which are interesting in their techniques as well as their thought style. Karst caves are very suitable for processing in terms of scraping, embossing and various painting techniques depending on the mineral structure of limestone. Besides, since these caves are difficult to access and are prevented from external dangers and risks, they are of great importance for the emergence of this art and reaching to the present day. Keywords: Cave, Karstic rock, Cave art

Coral rocks, as an iconic element of Bali's coast, have a central role in the island's art and culture. Music, musical arts and dance in Bali often use the character and unique shapes of coral rocks found along the coast to become inspiration for works of art. In Jembrana district, precisely in Pengeragoan village, there is Yeh Leh Beach, on this beach there are beautiful coral rocks which later became the inspiration for the creation of the creative percussion work entitled Wajaprani. The rock's sturdy character even when hit by waves is an inspiration for creating dynamic rhythms. with the character of the coral rocks on Yeh Leh Beach, the stylist thought it would be very suitable to use the medium of gamelan gong kebyar to implement the characters on the coral rocks.

A purported cemented sand sculpture found in Pleistocene aeolianite deposits on the Cape south coast of South Africa resembles a stingray (minus a tail) in outline. Symmetry is evident in the rock’s shape and the pattern of grooves on its surface. It is postulated that it may be a three-dimensional example of representational art of another species. Optically stimulated luminescence studies of rocks in the vicinity indicate that it dates to the Middle Stone Age, most probably during Marine Isotope Stage 5 (when high sea levels imply a nearby coastline). The correspondence in shape between the purported sand sculpture and the blue stingray (Dasyatis chrysonota) suggests that it may have been traced from a fresh specimen. Tracings on sand are postulated as a possible ‘stepping stone’ between abstract early palaeoart and representational rock art. Features of the rock suggest that the creation of a stingray sand sculpture may conceivably have been followed by symbolically wounding it and amputating its lethal end. Identification of further ammoglyphs will be important in refining the analysis of this newly identified form of early palaeoart.

The Bureau of Reclamation (BOR) is interested in understanding the human and environmental consequences of past Glen Canyon Dam water release policies and using these data to inform future water release and land management policies. One step in this direction is to understand how American Indian people have used the Colorado River and adjoining lands in Glen Canyon and Grand Canyon. The BOR, through its Glen Canyon Environmental Studies (GCES) office, has provided funds for various American Indian groups to identify places and things of cultural significance in the 300 mile long river and canyon ecosystem that has come to be called the Colorado River Corridor. This study is the second to report on the cultural resources of the Southern Paiute people found in this riverine ecosystem. The rock art study funded by the BOR and managed by the Glen Canyon Environmental Studies (GCES) office is the basis of this report. This study is unique in the history of rock art studies and is unusual when compared with other American Indian cultural resource assessments. There are five unique features of this study. First, all funds for conducting the research were contracted to the Southern Paiute Consortium. Second, the Southern Paiute people decided during the previous studies that their next study would be about rock art. Third, the GCES /BOR permitted research to be conducted in terms of Paiute perceptions of the study area rather than specifically in terms of the scientifically established study area for the project. Thus, it was possible to conduct the Kanab Creek side canyon study. Fourth, all interviews were guided by a ten -page survey instrument, so Southern Paiute responses could be systematically compared. Fifth, both all-male and all- female research trips were conducted, thus producing the first gender - specific interviews of rock art sites. The resulting study is both interdisciplinary and multivocal.

This government-to-government consultation between the Department of Energy, Nevada Operations Office (DOE /NV) and the Consolidated Group of Tribes and Organizations (CGTO) focused on the interpretation of 10 rock art sites; seven on the Nevada Test Site (NTS), and three on the Yucca Mountain Site Characterization Office (YMSCO). The consultation entailed a systematic ethnographic study of petroglyphs, pictographs, and other rock art manipulations. The objective of the project was to gain an understanding of the cultural significance of rock art for contemporary American Indians and its place in their traditional cultural landscapes. Research activities involved visits to rock art sites by tribal elders and tribal cultural experts. During the field visits, Indian consultants responded to standardized interviews and provided observations, comments, and recommendations regarding each of the sites under study. The project involved 14 American Indian tribes and two Indian organizations that represent Indian people having aboriginal and historic ties to lands currently occupied by the NTS. The study was initiated as part of the overall DOE /NV American Indian Program, which includes a decade of project - specific and general consultation efforts. This study built upon previous efforts and contributed to DOE /NV's understanding of American Indian cultural resources on the NTS.

This work is based on the comparative iconographic analysis of a distinct corpus of paintings within the Later Stone Age, Bushman or San art of southern Africa. They are distinct from the rest of the paintings of the region in age, numbers, variety, complexity and density. It defines in detail the principles that determined the form of the paintings - where the primary concern was to depict objects through outline alone - and the canon - the very restricted range of subjects that were depicted. It demonstrates that the human imagery established a set of archetypes, expressing concepts of the roles of men and women in the community through a set of readily legible attributes. The art was thus in essence conceptual and, of its nature, not concerned with the individual, illustration, narrative, documentation or anecdote. Within this framework, the paintings focused on concepts of the various forms and degrees of supernatural energy or potency that all San have believed to be inherent in every person. Further studies demonstrate how large and dangerous animals, particularly the elephant, were conceived as symbols of potency and their hunting as a metaphor for trance. Compositions based on oval shapes and the dots within and emanating from them are shown to be further symbols of aspects of potency. Many recurrent and hitherto ignored motifs attached to human figures are shown to be a graphic commentary on the metaphysics of the archetypes. The study is set in the context of the archaeology of the sub-region, recent studies of San concepts, perceptions and beliefs, a review of previous research, and a critique of influential recent South African work which first integrated paintings with San beliefs.

En el planteamiento previo de este trabajo nos propusimos cinco objetivos que hemos desarrollado a lo largo del estudio y que se detallan a continuación. 1) Documentación del mural La documentación gráfica del mural ha consistido en la realización de un calco digital del mural en base al programa Photoshop y con la ayuda de la aplicación DStrech. A partir de la documentación gráfica hemos identificado 194 motivos en distintas categorías de figuras animales, humanas y elementos esquemáticos y abstractos distribuidos en cinco sectores de la cueva. Todos estos motivos están reproducidos a escala en el calco general y situados en la planimetría de la cavidad. Además, hemos elaborado una aplicación de base de datos específica para nuestras investigaciones referentes al arte rupestre de las sierras centrales de Baja California. La intención es tener unas descripciones estandarizadas que permitan comparar los datos formales de las figuras de una cavidad entre sí y respecto a otros murales. En este estudio incluimos la descripción de la base de datos y su funcionamiento, así como la información perteneciente a la cavidad de El Ratón en forma de ficha individual de cada figura. 2) Proceso de realización del mural La documentación del mural ha servido para establecer el orden de superposición de las figuras que están en contacto y muestran una estratigrafía cromática. El establecimiento de estas superposiciones no está exento de problemas, derivados principalmente de la apreciación del anclaje de los pigmentos, las transparencias de los colores, los repintes y las reelaboraciones de las figuras. A partir de esta información hemos establecido el proceso de ejecución del mural. Para ello hemos tenido también en consideración elementos compositivos y rasgos formales de las figuras pintadas. El resultado son siete fases consecutivas dentro del proceso muralista. Hemos detallado los puntos en la documentación en los que nos hemos basado para establecer el proceso para que pueda juzgarse su idoneidad, y proponemos estudios más detallados que incluyan la elaboración de láminas delgadas en algunos puntos del mural para cerciorarnos de las superposiciones. Por otra parte, hemos confrontado la propuesta de fases que hemos establecido en El Ratón con las fases que R. Viñas propuso para La Pintada y hemos podido apreciar que algunas formas que caracterizan fases consecutivas de La Pintada siguen el mismo patrón en El Ratón. Esto es especialmente apreciable en la evolución del perfil de los cuerpos y la posición de las patas de los cuadúpedos. 3) Contexto cronocultural Durante mucho tiempo los Grandes Murales se han considerado como un fenómeno relativamente homogéneo vinculado con la cultura Comondú, en un periodo de tiempo incluido en las últimas fases de la prehistoria bajacaliforniana. A partir de las observaciones en distintos murales, nuestro equipo de trabajo advirtió que las fases pictográficas que se observan en algunos frisos podían contravenir esta idea inicial y descubrir que el proceso pictográfico de las sierras centrales de Baja California es dilatado en el tiempo. La documentación realizada por R. Viñas en La Pintada y ahora la que presentamos para el caso de El Ratón confirman esta hipótesis: hay una diversidad de momentos pictóricos en los murales que evidencian cambios culturales en un proceso diacrónico dilatado. R. Viñas propone una distinción entre los Grandes Murales con distintas fases internas —en La Pintada propone cuatro fases para los Grandes Murales—; otra etapa pictórica con la inclusión de nuevas formas gráficas que mantendrían elementos de los Grandes Murales, a la que llama «Tradición Gran Mural», y una etapa final en la que predominan los elementos esquemáticos y abstractos y que se desvincula formalmente de los Grandes Murales. Este esquema coincide con nuestras observaciones en El Ratón, donde las fases 1-3 corresponden plenamente a los Grandes Murales, las fases 4 y 5 se incluirían en esa «Tradición Grandes Murales» y las 6 y 7 se apartan formalmente de esta tradición. No obstante, esta propuesta no deja de ser un esquema inicial y el fenómeno rupestre en Baja California es muy complejo como para pensar que a esta tendencia general no le podremos añadir nuevos matices cuando se documenten un mayor número de cavidades pintadas. Las fases finales del arte rupestre de Baja California corresponden a los habitantes de la península que conocieron a los colonizadores europeos. Otra cuestión es establecer el inicio del proceso y las fases intermedias. Las fechas directas sobre los murales establecen una antigüedad que se remonta al Arcaico temprano. La fecha que consideramos fiable obtenida del puma n.º 41 de la cueva de El Ratón (4.845 ±60 BP) es coherente con este entorno de dataciones. Sin embargo, no podemos dar la cuestión por zanjada. En el futuro se deberán establecer proyectos de datación que persigan objetivos específicos. Proponemos la búsqueda de fechas radiocarbónicas que relacionen figuras de las fases de la cronología relativa que se deriva de la documentación, en espera de una coherencia que dé sentido al estudio del proceso y que, posteriormente, sea comparable con el estudio de otros murales. En el caso de El Ratón, la documentación presentada facilita el proceso de selección de figuras potencialmente interesantes para confirmar o corregir la propuesta de las fases pictóricas. 4) Análisis de la composición gráfica del mural El análisis de la composición gráfica del mural nos ha permitido identificar relaciones entre distintas figuras o elementos internos de las pinturas que hemos interpretado como códigos del lenguaje muralista. Los pintores han utilizados los motivos iconográficos, formas, colores, contactos entre figuras, relaciones de simetría, ubicación en el espacio, líneas visuales, sucesiones, actitud y posición de las figuras para crear estos códigos. Estos se manifiestan en ocasiones por su valor recurrente, otras por contraste u oposición y se hacen evidentes en la composición de manera que resultan significativos. Las relaciones codificadas permiten identificar la temática representada dentro del mismo mural, y observar diferencias de estos tratamientos entre sus distintas fases. Conforme avance el estudio de los murales podremos establecer la distribución en extensión geográfica y profundidad histórica de estos códigos y así se convertirán en un elemento para discernir el proceso histórico de los murales rupestres de Baja California. Podremos ver también cómo estos recursos se asemejan o diferencian entre las sierras de San Francisco, Guadalupe y San Borja en una visión amplia del fenómeno de los Grandes Murales. 5) Funcionalidad de la cueva de El Ratón Las cuevas pintadas de la sierra de San Francisco han sido consideradas, a menudo, como agreggaton sites. Tal como fueron definidos para el Paleolítico, estos son yacimientos donde se reúne un grupo numeroso de personas para llevar a cabo una serie de rituales y actos sociales y se caracterizan por una ocupación de mucha gente por poco tiempo. Se espera que esto se refleje de alguna manera en el sedimento arqueológico y en consecuencia quede rastro de la estacionalidad que caracteriza a estas reuniones. Por otro lado, el sitio ha de reunir unas condiciones que permitan concentrar un número importante de asistentes, abundancia de elementos rituales muebles y un panel decorado que presente elementos singulares y decoraciones genéricas. En nuestra opinión, no todas las cuevas pintadas del área de los Grandes Murales cumplían la misma función. Esta apreciación deriva de las obvias diferencias entre distintos tipos de cuevas pintadas que conocemos en las sierras de San Francisco. No es lo mismo una cueva como La Pintada con más de mil figuras, una temática muy variada, muchas fases de realización del mural y una extensión considerable, que pequeñas oquedades que pueden encontrarse en varios barrancos con un número reducido de pinturas, u otras cavidades de mediano tamaño, un mural relativamente con pocas pinturas y una temática unitaria. Pero por el momento, no tenemos unas características definidas que categoricen los distintos tipos de cueva pintada ni siquiera estos sitios de congregación. En el caso de la cueva de El Ratón hemos confrontado sus datos con los provenientes de La Pintada, La Serpiente y El Porcelano y hemos visto que participan de ciertas similitudes y diferencias significativas. En primer lugar, las cuevas de La Pintada y El Ratón son amplias y con una terraza que permite la reunión de un grupo considerable de personas. La cueva de La Serpiente es una grieta en el cantil que apenas puede albergar un número muy reducido de personas y El Porcelano es una cueva mediana sin mucho espacio para grandes reuniones. Si a estas propiedades morfológicas añadimos las características de los respectivos murales vemos que El Ratón y La Pintada comparten rasgos comunes en contraste con los casos de La Serpiente y El Porcelano. Las cuevas de El Ratón y La Pintada presentan una considerable variabilidad de rasgos estilísticos y de recursos técnicos, una paleta de colores amplia y un repertorio iconográfico extenso, a tal punto que los porcentajes son muy similares. Por el contrario, El Porcelano y La Serpiente muestran una gran homogeneidad interna de rasgos estilísticos y de recursos técnicos, una paleta de colores casi monótona y poca variabilidad iconográfica. Es decir, tienen unos rasgos formales muy homogéneos en sus respectivos murales aunque sean dispares entre sí. Por otra parte, en El Ratón y La Pintada existe un proceso de realización prolongado en el tiempo, con distintas fases pictóricas y numerosas superposiciones. Las características de cuatro cuevas pintadas no son suficientes para caracterizar sitios arqueológicos complejos como son los murales pintados de Baja California. Sin embargo, esta comparación orienta en la búsqueda de estas características. De manera provisional y presumiblemente incompleta proponemos que las características que pueden definir los lugares de congregación en la sierra de San Francisco: — Lugares amplios que permitan la reunión de un número importante de gente. — Murales que presenten una considerable variabilidad de rasgos técnicos, estilísticos, cromáticos e iconográficos. — El proceso muralista será dilatado en el tiempo y mostrará diferentes fases. — Probablemente presentarán un tema principal que se complementará en las sucesivas etapas pictóricas y, en algunos casos, se añadirán nuevos temas. Distintos a estos grandes santuarios, podemos encontrar sitios con pinturas que respondan a una temática muy particular, realizados en un momento histórico concreto sin que el uso más o menos continuado del sitio haya requerido ampliar o modificar el mural. Pensamos que corresponden a lugares donde se han celebrado rituales más privados o que han sido pintados por algún motivo muy concreto. Por lo que se refiere al sedimento arqueológico, hemos de advertir que en las cuevas pintadas de estas sierras la potencia estratigráfica es pobre y que el número de excavaciones de que disponemos es escaso. Por eso no nos atrevemos a predecir cómo sería este sedimento en relación con las cuevas pintadas en lugares de congregación. En todo caso, diremos que en El Ratón no hemos identificado disposiciones de material significativas más allá de una concentración del material en hilera paralela a la pared, y que sí hemos documentado unas estructuras de combustión peculiares en cuanto a su función, que pensamos que están relacionadas con los rituales que se llevaron a cabo en este santuario rupestre. Hemos de añadir que la temática representada la cueva de El Ratón muestra una serie de relaciones con temas mitológicos documentados etnográficamente en el entorno cultural, lo que permite una propuesta interpretativa del mural en relación con aspectos astronómicos ligados a los solsticios y, por lo tanto, a la mitología de la renovación estacional y mantenimiento de la periodicidad. Esta propuesta precisa de un estudio más detallado que incluya observaciones in situ en los periodos señalados —especialmente durante el solsticio de verano— y cálculos arqueoastronómicos que abarquen los periodos históricos que nos interese documentar. Para finalizar, presentamos este trabajo del mural de El Ratón como un elemento a tener en cuenta en el estudio global de los Grandes Murales y con la esperanza de crear discusión al respecto. Consideramos que para avanzar necesitamos documentaciones exhaustivas de los murales y el análisis individualizado de los mismos para poder, luego, contrastarlos. Para ello es necesario desarrollar metodologías de documentación que permitan comparaciones parangonables. En este empeño seguiremos trabajando.
The archaeological site of El Ratón Cave: A painted cave in the Sierra de San Francisco (Baja California Sur, Mexico). The painted mural. Albert Rubio i Mora In a previous proposal of this work, we set out five aims which have been developed throughout the present research. These are described below. 1) Recording of the mural painting The visual recording of the mural painting consisted of making a digital carbon copy of the mural using the Photoshop software and with aid of the DStrech plugin. Using this visual record, we have identified 194 motifs of various classes, animal figures, humans, schematic and abstract designs, scattered over five sections in the cave. All of these motifs have been reproduced to scale on the general copy and located in the planimetry of the cave. Additionally, we have compiled a special database for researching the rock art of the Baja California central mountain ranges, or sierras. The aim is to create a resource of standardised descriptions that will allow researchers to compare the formal qualities of the motifs at both the intra- and inter-site levels. In this study, we have included the description of the database and its use, as well as documentation of the data from El Ratón Cave in individual records for each figure. 2) The creation process of the mural The work of recording the painted mural has been useful to establish the order of superimposition of the overlapping figures, which has revealed a chromatic stratigraphy. Determining the order of superimposing images is not without its problems, particularly due to the difficulty of perceiving the pigment background, the colour overlay, and the repainting and modification of the motifs. Using this information, we have been able to establish the sequence of the creation process of the mural. To reconstruct this process, we have also taken into account the composition and formal properties of the figures. The result reveals seven consecutive phases of the painting process. We have detailed the aspects of the record upon which the reconstruction of the work process is based so that it can be assessed. We suggest more specific studies that include making thin prints of some mural sections to corroborate the superimpositions. Finally, we have contrasted our proposal of sequential painting phases at El Ratón with the phases suggested by R. Viñas for La Pintada. We concluded that certain forms which characterize the consecutive phases at La Pintada follow the same pattern at El Ratón. This is better appreciated in the evolution of the profile of the bodies and the position of the quadruped’s feet. 3) Chrono-cultural context For a long time, the Great Murals were considered a relatively homogeneous phenomenon linked to the Comondú culture, which belongs to the latter period of the Baja Californian prehistory. According to the observations made in several rock art sites, our research team noticed that the sequential pictorial phases of some of the panels seemed to contradict that initial assumption and showed that, to the contrary, the painting tradition of the central mountain ranges of Baja California had a long time depth. The recording of La Pintada by R. Viñas and our own research at El Ratón corroborate the hypothesis that there are different painting events in the mural tradition which reflect cultural changes in a long diachronic process. R. Viñas has distinguished various internal phases within the Great Murals. Based on the analysis at La Pintada, he has suggested four Great Mural phases, one pictorial period that includes novel motifs that keep to the elements of the Great Murals, which he has called Great Mural Tradition, and a final phase dominated by schematic and abstract motifs, which is formally removed from the Great Murals. This scheme coincides with our observations at El Ratón, where phases 1 to 3 clearly correspond with the Great Murals, phases 4 and 5 belong to the Great Murals Tradition, and 6 to 7 move away from that tradition. Nevertheless, this proposal is only an initial scheme and the rock art of Baja California is too complex to think that this trend will remain unchanged as more painted sites are recorded. The final phases of the rock art of Baja California belong to the peoples that inhabited the peninsula when the European pioneers arrived. A more pressing issue is to establish the age of the initial and intermediate phases. The direct dates obtained from the paintings suggest an age going back to the early Archaic. The most reliable date, obtained from figure no. 41, the puma, at El Ratón Cave (4,845 +60 BP) is coherent with the range of those dates. However, the issue is not completely resolved. Future dating projects should have well-defined aims. We suggest that radiocarbon dates should concentrate on relating specific figures to the phases of the relative chronology derived from our observations, in order to make sense of the creation process and create a data set that may be compared across mural sites. In the case of El Ratón, our recording can help towards the selection of motifs that could be used for sampling, to test the sequence of pictorial phases. 4) Analysis of the mural’s visual composition The analysis of the visual composition of the mural has thrown light on the associations among figures or internal elements of the paintings, which we interpret as the codes of the mural’s language. To create such codes, the artists seem to have used the iconographic motifs, forms, colours, image overlaps, symmetry relations, location in space, visual lines, sequences, attitude and situation of the motifs. These codes may be identified by their recurrence, contrast, or opposition and become evidently meaningful in the total composition. The codified associations allow us to identify the themes represented in the mural and to distinguish differences between those associations across the various phases. As the research of the murals moves forward we will be able to establish the geographical distribution and historical depth of such codes so that they will become a component that will aid in clarifying the history of the Great Murals of Baja California. We may also be able to observe whether the codes are similar or different across the sierras of San Francisco, Guadalupe and San Borja, in order to obtain a general picture of the Great Mural phenomenon. 5) The function of Cueva del Ratón The painted caves of sierra de San Francisco have often been considered as ‘aggregation sites’. These type of sites, initially defined for the European Palaeolithic, are locations where a numerous group of people convene to carry out a series of rituals and social activities. Thus, they are characterized by a short but intensive occupation. This would somehow be reflected in the archaeological record, leaving some traces of the seasonality that generally typifies such gatherings. Furthermore, the aggregation site should comply with certain conditions to allow the concentration of a large number of attendants, and it should contain portable ritual objects and decorated panels that show singular elements and general motifs. In our opinion, not all painted caves in the region of the Great Murals had the same function. This observation is based on the obvious differences between the various types of painted caves that are known in Sierra de San Francisco. For example, a cave like La Pintada – with over a thousand figures, varied themes, a mural with several creation phases and a large extension – is not the same as the small crevices scattered across the various cliffs with only a few paintings, or the medium-sized rock shelters that contain panels with relatively few figures and one theme. For now, we do not have a fixed set of criteria to categorise the different types of painted caves, or the aggregation sites. In the case of El Ratón Cave, we have contrasted our data against the data from the sites of La Pintada, La Serpeinte and El Porcelano, and we have been able to observe certain meaningful similarities and differences. First, the caves of La Pintada and El Ratón are big and both have a gallery that would allow the gathering of a large group of people. La Serpiente cave is a cliff crevice that can allow access to only a small number of people, and El Porcelano is a medium-sized cave with not much space for a gathering. If these morphological characteristics are seen side by side with the properties of each site’s paintings, we observe that El Ratón and La Pintada share several common traits , whereas this is not the case with La Serpiente and El Porcelano. The caves of El Ratón and La Pintada both show a considerable range of stylistic properties and techniques, an extensive colour palette and iconographic repertoire, to the point that their percentages are quite similar. In contrast, El Porcelano and La Serpiente show a great internal homogeneity of stylistic properties and techniques, an almost monotone colour palette, and little iconographic variety. That is to say, the formal properties of each site’s paintings are very homogeneous, although very different between them. Furthermore, El Ratón and La Pintada reflect a long creation process with different painting phases an numerous superimpositions. The characteristics of just four painted caves are not enough to embody the complex archaeological phenomenon that is the Great Mural rock art of Baja California. However, our observations can guide our search for such criteria. Provisionally and presumably incompletely, we suggest certain characteristics that may define the aggregation sites in the sierra de San Francisco: - Large sites that allow the gathering of a great number of people. - Murals that show considerable variability of techniques, styles, colours, and motifs. - The creation process will have a long time depth and will show several work phases. - Are likely to depict a main theme that will be expanded upon in successive painting stages, and in some cases, new themes will be added. In contrast to the large sanctuaries, there are sites with paintings that portray a singular theme, painted in one single historical moment. Even if these sites were sometimes used continuously over time their murals were not extended or modified. We think that these sites may have been used to celebrate more private rituals or were painted with a very particular aim. Regarding the archaeological sediment, we must point out that the painted caves of the Baja Californian sierras have a poor stratigraphy and the number of excavations has been scarce. For this reason, we can not make any suggestions as to how the sediment of the painted caves would differ from that of aggregation sites. In any case, we will mention that at El Ratón we have not been able to identify any relevant accumulation of archaeological material apart from a concentration of objects aligned to the cave wall. We also recorded some peculiar combustion structures whose function, we believe, may be related to the rituals that were carried out at this rock sanctuary. In addition, the theme depicted at El Ratón Cave has a series of similarities with mythological subjects documented in the ethnography of the cultural region. This allows us to suggest an interpretive reading of the mural in regards of astronomical topics related to the solstices, and consequently to the myth of the seasonal rebirth and cyclic continuity. This suggestion requires a more detailed study that should include in situ observation of the mentioned dates – especially, the summer solstice- and archaeoastronomic calculations that include the historical period we want to research. --- Finally, we present this study of El Ratón mural as a contribution to the global study of the Great Murals, and with it we hope to open a scholarly discussion. We believe that to move forward in this field we need extensive records of the murals and an individual analysis that can be tested afterwards. To this aim we need to develop recording methods that allow us to make reasonable comparisons. We will keep working towards that end.

Thesis (Ph. D.)--University of California, Riverside, 2010.
Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed May 19, 2010). Includes bibliographical references. Also issued in print.

[Truncated abstract] Many researchers have proposed the use of silicate rock fertilizers (SRFs) as alternatives to chemical fertilizers. However, the application of SRFs in modern agricultural practices is limited due mainly to the slow release of plant-nutrient elements from SRFs and consequently many tonnes/ha of SRFs may need to be applied. Simple and inexpensive methods of modifying the physicochemical properties of SRFs are needed to improve the agronomic effectiveness of SRFs. This thesis is focused on the evaluation of high-energy milling to produce superfine particles to improve the effectiveness of mafic (basalt and dolerite) and felsic (gneiss and K-feldspar) rocks for use as fertilizers. The ground mafic rocks are for use as Ca and Mg fertilizers and the ground felsic rocks as K fertilizers. Laboratory and glasshouse experiments were conducted with several potential SRFs. In laboratory experiments, initially milled rocks (Ø< 250 μm for basalt, dolerite, and gneiss; Ø < 150 μm for K-feldspar) were further milled with a ball mill (Spex-8000) for 10, 30, 60, 90, and 120 min under dry and wet (rock/water ratio = 1/3) conditions. To investigate possible reaction between constituents, other subsamples of initially milled basalt, dolerite, and gneiss were added to reagent grade NaCl or KCl (4.5 g rock + 0.5 g NaCl or KCl) and milled for 120 min under dry and wet conditions. Basalt and dolerite were also mixed with K-feldspar at a ratio of 1 : 1 and milled for 120 min under dry and wet conditions. For use in the glasshouse experiment, the initially milled rocks were further milled with a vertical stirred ball mill for 1 h in a dry condition. The elemental and mineralogical compositions of the SRFs were determined using XRF and XRD. Effects of milling on major physicochemical properties of milled rocks were determined, including particle size (Malvern Mastersizer), surface area (BET-N2), quantities of amorphous constituents (XRD, oxalic acid-oxalate extraction, TEM), extractable cations (1M CH3COONH4 pH 7), pHH2O, and electric conductivity. Dissolution kinetics in 0.01M acetic-citric acids (for 56 days) and soil (for 10 months) were determined. Based on the results of these laboratory experiments, a glasshouse experiment was carried out for 12 months to evaluate the effects of SRF application on growth and nutrient uptake of ryegrass grown on several soils. Milling reduced particle size, enhanced amorphism, and increased the release of structural cations from the rocks, with the effects due to dry milling being greater than for wet milling. The optimum milling times which produced maximum amounts of exchangeable cations (Na, K, Ca, and Mg) were 30 - 90 min, depending on rock type. The use of NaCl and KCl as milling additives did not enhance the properties of the SRF

This study aims to examine all aspects of Moroccan rock art and place it in an archaeological and environmental context. Almost 300 sites are now known but few have been studied fully. This work is the first overall analysis to be attempted. Data on climatic changes during the Holocene period, together with archaeological and faunal reports, provided the necessary background to the rock art. The distribution of engraved and painted sites in Morocco is very uneven. Animals were the most frequent themes, but a review of all the sites revealed great site and subject diversity. Four main types of engravings were Identified, their Characteristics described and their distribution plotted. Climatic fluctuations, new animal species, the introduction of meth weapons, the chariot and writing established a chronological framework. A critical appraisal of these events led to a tentative chronology for Moroccan rock art, thought here to have started around 2500 be. The situation of rock art sites showed that they were chosen for very specific reasons, some of them by nomadic pastoralists. Viewing rock art as a medium of communication, it was proposed that the images were messages defining territories, proclaiming ownership or commemorating heroes or battles. The images may have two levels of meaning: one easily understood by members of the group and by outsiders, the second, symbolic, less obviously comprehensible. Moroccan rock art was not an isolated phenomenon in north Africa. The rock art of Algeria, Libya and Mauritania showed both similarities and differences, IrnpMng a cultural link, albeit tenuous, between these countries. Available archaeological, environmental and rock art data revealed striking differences In information-availability between north and south Morocco. Archaeological research has established a chronologicaal nd cultural framework, in northern Morocco,to which rock art adds nothing. On the other hand, rock engravings of metal weapons are almost the only evidence of a Moroccan Bronze Age. In southern Morocco, the distribution of rock art sites reveals intensive human activity in an area little known from excavation. Rock art, archaeology and environment are thus related in this study to producea comprehensive picture of the past.

AbstractBoth on and off the rocks, it is clear that many pictographs and petroglyphs are powerful cultural and social ‘tools’ as well as sacred beings. Indeed, in certain regions of many countries, cultural and socio-political identity is shaped, manipulated, and presented through rock paintings and engravings. In this chapter, we focus on re-contextualised and appropriated Indigenous heritage and rock art motifs, in commercial settings, in sports team mascots, and as integral components of political and national symbols—there are illuminating similarities (as well as differences) that span the globe. Case studies include instances where descendants of the original artists have re-imagined and adapted the meanings and uses of motifs, and also where non-Indigenous/non-descendant groups have appropriated rock art imagery—often without consultation with or permission from Traditional Owners and heritage managers. We offer results from fieldwork and study in North America, northern Australia, and southern Africa.

AbstractDepictions of weapons and of armed human figures in Camunianand Alpinerock art are common, particularly after the advent of metalwork and especially beginning with the Copper Age. They are found on monuments and on rocks, as can be seen clearly in the megalithic sanctuaries featuring stelae, anthropomorphic stelae, and statues-menhir, as well as in the most significant Alpine spiritual centers and elsewhere, such as Val Camonica (It. Valle Camonica, Lo. Al Camònega), Mount Bego (Mont Bégo), Val Tellina, and Monte Baldo, on the Veroneseshore of Lake Garda (Lago di Garda). Depictions of weapons are important for the chronological and cultural placement of the engraved complexes; the depictions of armed human figures that dominate some Alpine engraving sets are no less important. That is particularly the case in Val Camonica and Val Tellina, over a very long period of time running from the Bronze Age up to the Iron Age and even into prehistoric times. The depictions of men holding weapons—in a wide variety of stylistic, iconographic, and compositional arrangements, and belonging to many different periods and stages of engraving—represent a ritual language that was used at the very time the pictures were being created. They are an evocative language that commemorated, revived, and spoke of mythical forefathers, ancestral heroes, departed warriors, founders of communities, and indeed anyone who played an important role in the past and became an object of worship. The ritual gesture of depicting them might have served the ritual function not only of commemoration but of calling their presence back from the past into the community in times of particular need.

When studying objects of mobile art in the Stone Age of Kamchatka, it was assumed that the most ancient artifacts were personal ornamentation (~final Paleolithic, 13.3-12.5 thousand years ago, 12.0-10.1 thousand years ago). These are beads and pendants made of pyrophyllite, agalmatolite, amber, quartzite, slate Stone sculpture was made in the Neolithic (~7.8-4.5 thousand years ago - the beginning of the 2nd millennium AD), while throughout the entire period the ancient artist depicted figurines of fish. Various zoomorphic sculptures (whales, seals, bears, deer, dogs, foxes) appeared in the Middle Neolithic era (~4000-1500 years ago). This is probably due to the formation of a new fauna at that time. During the same period, anthropomorphic sculpture were made. The stone figures are made of local stone rocks (obsidian, flint, chalcedony, basalt) with flake stone technology and sharp retouching. The objects could be used in ritual activities, depict characters from Itel'men myths.

Abstract Central Luconia province is located in South China Sea, Sarawak with development of more than 250 carbonate pinnacles and platform in Middle Miocene to Late Miocene. The study proposes a methodology that has been successfully applied and calibrated to 20 exploration or appraisal wells in both carbonate pinnacles and platform with the objective to model pore types from compressional velocity and subsequently used it for permeability prediction based on Lucia's rock fabric number (RFN). Porosity, permeability, petrography and mercury injection pressure (MICP) data of more than 2000 core plugs and sidewall core samples were analyzed to establish functions in between compressional velocity, pore types and permeability. This paper is established based on two concepts by many authors in the past, but no publication to date has linked these two concepts together. The first concept is the poroelastic behavior of carbonate rock under constant pressure and 100% water saturation is controlled primarily by a combination of porosity and pore geometry (Wyllie et. al., 1958; Anselmetti & Eberli, 1993; Anselmetti et. al. 1997; Eberli et. al., 2003). High aspect ratio pores sample such as molds and vugs, typically has higher pore throat size. The sonic velocity of this sample will plot above Wyllie-time-average (WTA) equation. Low aspect ratio pores such as interparticle and intercrystalline pores, typically has lower pore throat size. The sonic velocity of this sample will plot below WTA equation. The second concept is the Lucia rock fabric number (RFN) which described porosity – permeability relationships for various particle- size groups in non-vuggy or interparticle porosity rocks only. However, our MICP dataset conclude that Lucia RFN number is inversely proportional to dominant pore throat size in carbonate rock with little to no presence of primary porosity. The dominant pore throat size was determined based on the apex of curve in the crossplot of mercury saturation divided by injection pressure to mercury saturation.

Abstract Objectives/Scope X-ray Micro-Computer Tomography (μ-CT) has been widely adopted in earth science and petroleum engineering due to its non-destructive characteristic. Meanwhile, this three-dimensional-imaging method can be integrated with computer simulation to investigate petrophysical properties of reservoir rocks at pore scales. However, the application of μ-CT is limited by the trade-off between field of view and resolution, and it is challenging to indicate the pore structure of rocks, especially for shale or carbonate rocks. To address this issue, deep-learning-based super-resolution techniques have rapidly developed in the past few years. Methodology In this study, a super-resolution algorithm based on the state-of-the-art (STOA) diffusion model is proposed to generate super-resolved CT images for carbonate rocks. The proposed method adapts denoising diffusion probabilistic models to conditional image generation and performs super-resolution through a stochastic denoising process. Cascaded diffusion model is utilized to increase the training speed and generate high fidelity CT images. This method exhibits superior performance in the resolution-enhancement of CT images at various magnification factors (with a large scaling factor of up to 16) without the occurrence of image-noise and image-blurring issue, and the super-resolved CT images performs well for the calculation of petrophysical properties of carbonate rocks. Results This algorithm is applied to the carbonate rock and the performance of the diffusion model is evaluated by quantitative extraction and qualitative visualization. In addition, this method is compared with other methods, such as GAN, Variational Autoencoder, and Super-Resolution Convolutional Neural Networks (SRCNN). The results indicate that the built model shows excellent potential in enhancing the resolution of heterogeneous carbonate rocks. To be specific, the super-resolved images exhibit clear and sharp edges and a detailed pore network. In addition, it performs well on different upscaling factors (up to 16) and is superior to the existing super-resolution approaches (for both supervised and unsupervised algorithms). This study provides a novel deep-learning-based method using a diffusion model to enhance the resolution of μ-CT images of carbonate rocks (up to 16). Novelty The novelty of this study is three-fold. First, this method belongs to unsupervised learning, indicating that pairs of high-resolution and low-resolution CT images are no longer needed. Second, a large scaling factor (up to 16) is reached without an image-blurring issue, which normally occurs in other deep-learning-based super-resolution algorithms. Third, the quality of super-resolved images is promising and faithful when compared with other generated learning methods, such as Generative Adversarial Networks (GAN).

Solar thermal power plants are a promising option for future solar electricity generation. Their main advantage is the possibility to utilize integrated thermal storage capacities, allowing electricity generation on demand. In state of the art solar thermal power plants, two-tank molten-salt thermal energy storages are used. Significant cost reductions are expected by using thermocline thermal energy storage by storing the liquid storage material inside a single tank when compared to a two tank storage system. By embedding a low cost solid filler material inside the storage tank further cost reductions can be achieved. In earlier studies [1, 2] several potential filler materials have been investigated. In these study quartzite turned out to be a promising candidate due to its satisfying thermal stability and availability. At a temperature of approx. 573°C the crystal structure of quartzite changes from trigonal α-quartz phase to the hexagonal β-quartz phase [3]. This quartz conversion results in a volume change [4] that may cause cracking of the quartzite crystals due to weight loads in a packed bed. Since these thermal tests of the study mentioned were limited to 500°C this dunting was not considered. Thus, despite of the published studies there is a need for further, more detailed analysis. One trend in today’s development of solar thermal power plants is to use molten salt as storage material and heat transfer fluid at operating temperatures of 560°C and above. Accordingly, the quartz inversion might limit the applicability of quartzite as a filler material at elevated operating temperatures. Due to this concern, an investigation has been started to investigate the utilizability of natural rocks as low cost filler materials. In the first phase of this investigation a comprehensive literature survey was conducted. Based on this study, magmatic and sedimentary rocks turned out to the most promising rock classes for this application. For the further investigation, basalt was chosen as a suited representative for magmatic and quartzite for sedimentary rocks. In lab-scale tests, these candidate materials were investigated with respect to their: • Calcite content • Thermal stability up to 900°C in air • Thermal stability up to 560°C in molten salt • Cyclic stability between 290°C and 560°C in molten salt • Specific heat capacity up to 600°C In this paper the results of these investigations are presented and future activities are outlined.

Abstract The petroleum industry is one of the few industries that deal with high-pressure high-temperature conditions involving complex fluid behavior, rocks and their interactions, and flow dynamics in the subsurface. Moreover, petroleum industry has the critical domain expertise to reach and manage deep reservoirs both onshore and offshore. These capabilities and know-how put petroleum industry at the forefront to capture, utilize, and store carbon dioxide and other greenhouse gases in the subsurface. The objective of this paper is to review the existing body of literature and outline the most prominent methods or options to manage carbon dioxide (CO2) and other gases. We present the rigorous efforts presented in the literature to implement carbon capture, utilization, and storage (CCUS) projects, in the context of technological challenges, capacities, and perspectives. We categorize the options into three groups: Currently available technologies Near future technology Long term technology Categories (2) and (3) are discussed in terms of cost and scale-up, where both can be an impediment for wide-scale deployment. Many such options are functions of the energy price and as well as local incentives. Therefore, while focusing on the technical aspect we also discuss some of the enabling factors for its application. Some of the elements of (2) are also related to source-sink match yet direct air capture is being highlighted as a remedy of this issue while the costs are still an impediment for widespread use. This paper presents important conclusions from CCUS case studies across the globe within the petroleum industry, including US, Canada, China, Brazil, Norway, and beyond. Moreover, we examine methods that use carbon dioxide and other gases to improve the recovery of hydrocarbons and simultaneously store concentrated CO2 in the subsurface. We also review some of the midstream and petrochemical efforts for transport of CO2 and utilization, including chemical synthesis of materials. Our main conclusion in this review paper is that the petroleum industry has all of the tools and expertise to implement and adopt CCUS projects and to contribute to the sustainable future from a technological perspective. We show that there are many well-established methods in the petroleum industry that can be used directly for CCUS purposes. The petroleum industry may be regarded as a contributor to carbon and other gas emissions, however, in this paper we present the reverse concept that the petroleum industry has all the necessary tools and expertise to capture, utilize, and store carbon gases. The perspective presented in this paper will help petroleum industry to recognize its own strengths with the goal to reduce emissions not only within our industry but also to lead carbon emission reduction efforts from other industries.

Rho-associated coiled-coil kinases (ROCKs) are involved in essential cellular functions such as adhesion, contraction, motility, proliferation, and cell survival/apoptosis. Four ROCK inhibitors have already been approved by the FDA and are used to treat glaucoma (ripasudil and netarsudil), cerebral vasospasm (fasudil), and graft-versus-host disease (belumosudil). Recent studies have focused on exploring the role of ROCK kinase inhibitors in cancer treatment and the development of new ROCK inhibitors. The main objective of this study was to identify critical structural features relevant to the inhibition of ROCK1 using a ligand-based 3D-QSAR (3D quantitative structure-activity relationship) method. The 3D-QSAR model for ROCK1 was created and validated using internal and external validation parameters (R2, Q2, R2pred, rm 2, r/2m, rm̅̅2̅ and ∆r2m). The main structural features that correlate with the inhibition of ROCK1 were identified (e.g., heterocycle with hydrogen donor group like nitrogen atom) and further structural modifications of the ROCK1 inhibitors that contribute to increased activity were proposed (removal of the amino group of the oxadiazole, modification of the substituents of the phenyl ring).

Paleozoic platform carbonate rocks of the Rocky Mountains host Mississippi Valley-type (MVT), magnesite, barite, and REE-barite-fluorite deposits. Farther west, platform carbonate rocks of the Kootenay Arc host MVT and fracture-controlled replacement (FCR) deposits. This is the first systematic LA-ICP-MS study of carbonates in MVT and FCR deposits. We investigated seven MVT deposits in the Rocky Mountains, and five MVT deposits in the Kootenay Arc. None of the post-Archean Australian shale (PAAS)-normalized REE profiles show light REE (LREE) depletion and strong negative Ce anomalies characteristic of modern seawater: some profiles are nearly flat; others show depletion in LREE similar to seawater but without negative Ce anomalies; others are middle REE enriched. Carbonates with a strong positive Eu anomaly precipitated from or interacted with different fluids than carbonates with flatter profiles without a strong positive Eu anomaly. REE signatures reflect crystallization conditions of primary carbonates, and crystallization and re-equilibration conditions of carbonates with ambient fluids during diagenesis, deep burial, and/or metamorphic recrystallization. Chemical evolution of fluids along their migration path, fluid-to-rock ratio, fluid acidity, redox, and temperature also influence REE profile shape, which helps establish genetic and timing constraints on studied deposits and improves knowledge of the metallogeny of the Kootenay Arc and Rocky Mountains.

This file provides whole-rock assay and supporting metadata for 35 samples of phosphate ore and associated rocks from mine, refinery, and prospect entities in southwestern Montana. These assays are to investigate the critical mineral potential of the Phosphoria Formation of sedimentary rocks in Montana.

This volume presents results of research conducted during phase 5 of the Volcanic- and Sedimentary-hosted Base Metals Ore Systems project of the Geological Survey of Canada's Targeted Geoscience Initiative (TGI) program. The papers in this volume include syntheses and primary scientific reports. We present here a synopsis of the findings during this TGI project. Research activities have addressed several mineral deposit types hosted in sedimentary rocks: polymetallic hyper-enriched black shale, sedimentary exhalative Pb-Zn, carbonate-hosted Pb-Zn (Mississippi Valley-type; MVT), and fracture-controlled replacement Zn-Pb. Other carbonate-hosted deposits studied include a magnesite deposit at Mount Brussilof and a rare-earth element-F-Ba deposit at Rock Canyon Creek, both of which lack base metals but are spatially associated with the MVT deposits in the southern Rocky Mountains. Volcanogenic massive-sulfide deposits hosted in volcanic and mixed volcanic-sedimentary host rock settings were also examined. Through field geology, geochemical (lithogeochemistry, stable and radiogenic isotopes, fluid inclusions, and mineral chemistry), and geophysical (rock properties, magnetotelluric, and seismic) tools, the TGI research contributions have advanced genetic and exploration models for volcanic- and sedimentary-hosted base-metal deposits and developed new laboratory, geophysical, and field techniques to support exploration.

Grand Canyon National Park is all about time and timescales. Time is the currency of our daily life, of history, and of biological evolution. Grand Canyon’s beauty has inspired explorers, artists, and poets. Behind it all, Grand Canyon’s geology and sense of timelessness are among its most prominent and important resources. Grand Canyon has an exceptionally complete and well-exposed rock record of Earth’s history. It is an ideal place to gain a sense of geologic (or deep) time. A visit to the South or North rims, a hike into the canyon of any length, or a trip through the 277-mile (446-km) length of Grand Canyon are awe-inspiring experiences for many reasons, and they often motivate us to look deeper to understand how our human timescales of hundreds and thousands of years overlap with Earth’s many timescales reaching back millions and billions of years. This report summarizes how geologists tell time at Grand Canyon, and the resultant “best” numeric ages for the canyon’s strata based on recent scientific research. By best, we mean the most accurate and precise ages available, given the dating techniques used, geologic constraints, the availability of datable material, and the fossil record of Grand Canyon rock units. This paper updates a previously-published compilation of best numeric ages (Mathis and Bowman 2005a; 2005b; 2007) to incorporate recent revisions in the canyon’s stratigraphic nomenclature and additional numeric age determinations published in the scientific literature. From bottom to top, Grand Canyon’s rocks can be ordered into three “sets” (or primary packages), each with an overarching story. The Vishnu Basement Rocks were once tens of miles deep as North America’s crust formed via collisions of volcanic island chains with the pre-existing continent between 1,840 and 1,375 million years ago. The Grand Canyon Supergroup contains evidence for early single-celled life and represents basins that record the assembly and breakup of an early supercontinent between 729 and 1,255 million years ago. The Layered Paleozoic Rocks encode stories, layer by layer, of dramatic geologic changes and the evolution of animal life during the Paleozoic Era (period of ancient life) between 270 and 530 million years ago. In addition to characterizing the ages and geology of the three sets of rocks, we provide numeric ages for all the groups and formations within each set. Nine tables list the best ages along with information on each unit’s tectonic or depositional environment, and specific information explaining why revisions were made to previously published numeric ages. Photographs, line drawings, and diagrams of the different rock formations are included, as well as an extensive glossary of geologic terms to help define important scientific concepts. The three sets of rocks are separated by rock contacts called unconformities formed during long periods of erosion. This report unravels the Great Unconformity, named by John Wesley Powell 150 years ago, and shows that it is made up of several distinct erosion surfaces. The Great Nonconformity is between the Vishnu Basement Rocks and the Grand Canyon Supergroup. The Great Angular Unconformity is between the Grand Canyon Supergroup and the Layered Paleozoic Rocks. Powell’s term, the Great Unconformity, is used for contacts where the Vishnu Basement Rocks are directly overlain by the Layered Paleozoic Rocks. The time missing at these and other unconformities within the sets is also summarized in this paper—a topic that can be as interesting as the time recorded. Our goal is to provide a single up-to-date reference that summarizes the main facets of when the rocks exposed in the canyon’s walls were formed and their geologic history. This authoritative and readable summary of the age of Grand Canyon rocks will hopefully be helpful to National Park Service staff including resource managers and park interpreters at many levels of geologic understandings...

The Finlayson Lake district in southeastern Yukon is composed of a Late Paleozoic arc-backarc system that consists of metamorphosed volcanic, plutonic, and sedimentary rocks of the Yukon-Tanana and Slide Mountain terranes. These rocks host &amp;gt;40 Mt of polymetallic resources in numerous occurrences and styles of volcanogenic massive sulphide (VMS) mineralization. Geochemical and isotopic data from these rocks support previous interpretations that volcanism and plutonism occurred in arc-marginal arc (e.g., Fire Lake formation) and continental back-arc basin environments (e.g., Kudz Ze Kayah formation, Wind Lake formation, and Wolverine Lake group) where felsic magmatism formed from varying mixtures of crust- and mantle-derived material. The rocks have elevated high field strength element (HFSE) and rare earth element (REE) concentrations, and evolved to chondritic isotopic signatures, in VMS-proximal stratigraphy relative to VMS-barren assemblages. These geochemical features reflect the petrogenetic conditions that generated felsic rocks and likely played a role in the localization of VMS mineralization in the district. Preliminary in situ zircon chemistry supports these arguments with Th/U and Hf isotopic fingerprinting, where it is interpreted that the VMS-bearing lithofacies formed via crustal melting and mixing with increased juvenile, mafic magmatism; rocks that were less prospective have predominantly crustal signatures. These observations are consistent with the formation of VMS-related felsic rocks by basaltic underplating, crustal melting, and basalt-crustal melt mixing within an extensional setting. This work offers a unique perspective on magmatic petrogenesis that underscores the importance of integrating whole-rock with mineral-scale geochemistry in the characterization of VMS-related stratigraphy.

New geological mapping in the Tehery Lake-Wager Bay area of northwestern Hudson Bay, Nunavut, frames the emplacement, depositional, and metamorphic histories of the dominant rock types, major structures, and links to neighbouring areas of the central Rae Craton and Chesterfield Block. The area is divided into six domains (Ukkusiksalik, Douglas Harbour, Gordon, and Lunan domains presented here, and Kummel Lake Domain and Daly Bay Complex on adjoining maps) defined by large-scale structures and characterized by differing metamorphic assemblages, Sm-Nd and U-Pb isotopic data, and/or specific lithologies. Meso- to Neoarchean granitoid rocks underlie most of the area and are tectonically intercalated with Archean (volcano)sedimentary packages (Kummel Lake, Lorillard, and Paliak belts). These rocks are locally intruded by ca. 2.62 to 2.58 Ga Snow Island suite granite and cut by younger, thin, east-trending diabase dykes. Paleoproterozoic (volcano)sedimentary rocks are preserved in the Kingmirit belt (Daly Bay Complex) and in basement-cover infolds of Ketyet River group-equivalent strata (Douglas Harbour and Ukkusiksalik domains). In the south, the Daly Bay Complex (comprising mostly mafic granulite-facies rocks) and Kummel Lake Domain (a granulite-grade core complex) share some characteristics with rocks of the Kramanituar and Uvauk complexes, which may delineate the northeastern segment of the ca. 1.90 Ga Snowbird tectonic zone. The Paleoproterozoic Trans-Hudson Orogeny had widespread, penetrative structural and metamorphic effects on the area, and led to the intrusion of the ca. 1.85 to 1.81 Ga Hudson suite monzogranite and mafic ultrapotassic rocks, and ca. 1.83 Ga monzodiorite in the Ukkusiksalik and Douglas Harbour domains. The area is cut by large, southeast-trending gabbro dykes of the 1.267 Ga Mackenzie igneous event.

New geological mapping in the Tehery Lake-Wager Bay area of northwestern Hudson Bay, Nunavut, frames the emplacement, depositional, and metamorphic histories of the dominant rock types, major structures, and links to neighbouring areas of the central Rae Craton and Chesterfield Block. The area is divided into six domains (Ukkusiksalik, Douglas Harbour, and Gordon domains and Daly Bay Complex presented here, and Lunan and Kummel Lake domains on adjoining maps) defined by large-scale structures and characterized by differing metamorphic assemblages, Sm-Nd and U-Pb isotopic data, and/or specific lithologies. Meso- to Neoarchean granitoid rocks underlie most of the area and are tectonically intercalated with Archean (volcano)sedimentary packages (Kummel Lake, Lorillard, and Paliak belts). These rocks are locally intruded by ca. 2.62 to 2.58 Ga Snow Island suite granite and cut by younger, thin, east-trending diabase dykes. Paleoproterozoic (volcano)sedimentary rocks are preserved in the Kingmirit belt (Daly Bay Complex) and in basement-cover infolds of Ketyet River group-equivalent strata (Douglas Harbour and Ukkusiksalik domains). In the south, the Daly Bay Complex (comprising mostly mafic granulite-facies rocks) and Kummel Lake Domain (a granulite-grade core complex) share some characteristics with rocks of the Kramanituar and Uvauk complexes, which may delineate the northeastern segment of the ca. 1.90 Ga Snowbird tectonic zone. The Paleoproterozoic Trans-Hudson Orogeny had widespread, penetrative structural and metamorphic effects on the area, and led to the intrusion of the ca. 1.85 to 1.81 Ga Hudson suite monzogranite and mafic ultrapotassic rocks, and ca. 1.83 Ga monzodiorite in the Ukkusiksalik and Douglas Harbour domains. The area is cut by large, southeast-trending gabbro dykes of the 1.267 Ga Mackenzie igneous event.

New geological mapping in the Tehery Lake-Wager Bay area of northwestern Hudson Bay, Nunavut, frames the emplacement, depositional, and metamorphic histories of the dominant rock types, major structures, and links to neighbouring areas of the central Rae Craton and Chesterfield Block. The area is divided into six domains (Gordon, Lunan, and Kummel Lake domains presented here, and Ukkusiksalik and Douglas Harbour domains and Daly Bay Complex on adjoining maps) defined by large-scale structures and characterized by differing metamorphic assemblages, Sm-Nd and U-Pb isotopic data, and/or specific lithologies. Meso- to Neoarchean granitoid rocks underlie most of the area and are tectonically intercalated with Archean (volcano)sedimentary packages (Kummel Lake, Lorillard, and Paliak belts). These rocks are locally intruded by ca. 2.62 to 2.58 Ga Snow Island suite granite and cut by younger, thin, east-trending diabase dykes. Paleoproterozoic (volcano)sedimentary rocks are preserved in the Kingmirit belt (Daly Bay Complex) and in basement-cover infolds of Ketyet River group-equivalent strata (Douglas Harbour and Ukkusiksalik domains). In the south, the Daly Bay Complex (comprising mostly mafic granulite-facies rocks) and Kummel Lake Domain (a granulite-grade core complex) share some characteristics with rocks of the Kramanituar and Uvauk complexes, which may delineate the northeastern segment of the ca. 1.90 Ga Snowbird tectonic zone. The Paleoproterozoic Trans-Hudson Orogeny had widespread, penetrative structural and metamorphic effects on the area, and led to the intrusion of the ca. 1.85 to 1.81 Ga Hudson suite monzogranite and mafic ultrapotassic rocks, and ca. 1.83 Ga monzodiorite in the Ukkusiksalik and Douglas Harbour domains. The area is cut by large, southeast-trending gabbro dykes of the 1.267 Ga Mackenzie igneous event.

The Mississippi Valley-type, magnesite, and REE-F-Ba deposits in the southeastern Canadian Cordillera are in the weakly deformed/metamorphosed Paleozoic carbonate platform of the Rocky Mountains. Most are hosted in dolostones of the middle Cambrian Cathedral, upper Cambrian Jubilee, and Upper Devonian Palliser formations and spatially associated with hydrothermal dolomite. They occur along structurally controlled facies transitions between the shallow-water carbonate platform and deeper water basin rocks of the Paleozoic continental margin. Their location and morphology reflect episodic rifting along the Paleozoic margin. The carbonate protolith was replaced by fine-grained 'replacive dolomite' followed by several stages of coarser saccharoidal, sparry, and saddle dolomites and sulfides replacing dolostone and filling open spaces. The 87Sr/86Sr, delta-18O, delta-13C, and fluid-inclusion data are consistent with high-temperature fluids interacting with host rocks and show influence of adjacent or underlying siliciclastic rocks. The large range of delta-34S values of sulfides suggests that thermochemical sulfate reduction of seawater sulfate was the main sulfur-reducing process, but bacterial sulfate reduction also occurred locally. Lead isotopes suggest a mixing trend involving highly radiogenic and non-radiogenic end members. These observations are consistent with hydrothermal fluids replacing protoliths, precipitating sulfides, and possibly REE-F-Ba mineralization.