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Sediment hosted replacement gold deposits, also termed Carlin-type gold deposits from where they were first described, have been major gold producers in the western U.S. (98.8 million ounces discovered; Singer, 1993). Most deposits lie along deep crustal fracture systems which define the Carlin and Battle Mountain Trends (Madrid and Roberts, 1990). Significant new discoveries within the Carlin Trend include the Betze-Post and Meikle ore systems (Bettles and Lauha, 1991), with production of 7.1 million ounces andreserves of 28 million ounces of gold at the end of 1994 (Volk et al, 1995). Reviews of this style of gold mineralization by Bagby and Berger (1985), Sawkins (1984), Sillitoe and Bonham (1990), Berger and Bagby (1991), and Kuehn and Rose (1995) present geological models for this deposit type. Critical in the development of these models has been the recognition of similar deposit types in other settings (e.g., Bau, Sarawak; Wolfenden, 1965; Sillitoe and Bonham, 1990: China; Cunningham et al., 1988: Melco and Barney's Canyon deposits, Bingham District, U.S.; Babcock et al., 1992: Mesel, North Sulawesi; Indonesia; Turner et al., 1994; Garwin et al., 1995: and elsewhere in the eastern and western Pacific Rim, G. Corbett and T. Leach, unpub. data; Gemuts et al, 1996: Fig. S.l).
The term “provenance” originates from the Latin word “provenire,” meaning to originate. Although commonly used to indicate source or parent rock from which sediments were generated, the term “provenance” actually encompasses all factors related to sediment production, with “specific reference to the composition of the parent rocks as well as the physiography and climate of the source area” (Weltje and Eynatten, 2004). Sedimentary provenance data play a critical role in assessing palaeogeographic reconstructions, in constraining lateral displacements in orogens, in characterizing crust that is no longer exposed, in mapping depositional systems, in subsurface correlation, and in predicting reservoir quality (Haughton et al., 1991; Weltje and Eynatten, 2004; Garzanti et al., 2014; Bhattacharya et al., 2016). <...>
This cutting-edge summary combines ideas from several sub-disciplines, including geology, geomorphology, oceanography and geochemistry, to provide an integrated view of Earth surface dynamics in terms of sediment generation, transport and deposition. Introducing a global view of fundamental concepts underpinning source-to-sink studies, it provides an analysis of the component segments which make up sediment routing systems. The functioning of sediment routing systems is illustrated through calculations of denudation and sedimentation as well as the response to external drivers; with the final sections focusing on the stratigraphic record of sediment routing systems. Containing quantitative solutions to a wide range of problems in Earth surface dynamics, this book is suitable for graduate students as well as academic and professional researchers. philip a. allen is Emeritus Professor of Sedimentary Geology at Imperial College London and a process-oriented Earth scientist with a particular interest in the interactions and feedbacks between the solid Earth and its ‘exosphere’ through the critical interface of the Earth’s surface. He has received the Royal Society Wolfson Research Merit Award for 2006 to 2011 and the Lyell Medal from the Geological Society of London in 2007. He served on the Council of the Geological Society from 2008 to 2012, and was Secretary of the Science Committee from 2009 to 2012.
Sediment transport has been, and still is today, one of the most fascinating and challenging research topics in coastal, hydraulic, and environmental engineering. Probably first studies on sediment transport problems can be tracked back to ancient historical periods (i.e., Roman Empire, Egypt etc.) in relation to the sizing and mainte-nance of irrigation canals e.g. [1]. Obviously in this periods problems have been solved only by empirical trial and error method. First theoretical concepts can be referred to DuBuat (1734–1809) who was the first to talk about the concept of shearresistance e.g.[1]. In the following years, there have been many researchers who have contributed to the topic from a theoretical, empirical or experimental point of view (e.g. Du Puit, DuBoys, Reynolds, Forchheimer, Schoklitsch Shields, kennedy, Einstein, and Bagnold) e.g. [1]. In the past, the most of the research is devoted to understand and model the physical processes in order to estimate, for example, the shear stress, the order of magnitude of the sediment transport, bed shear stress and forms. <...>
Sediment-hosted gold deposits in Guizhou, China, are hosted in late Paleozoic and early Mesozoic sedimentary rocks along the southwest margin of the Precambrian Yangtze craton. They have characteristics similar to Carlin-type gold deposits in Nevada and are notably enriched in As, Sb, Hg, and Tl. The Shuiyindong and Yata deposits consist of disseminated, strata-bound sulfides in Permian bioclastic limestone and fault-controlled mineralization in Middle Triassic calcareous clastic rocks, respectively. Mineralization in both deposits consists of barren milky quartz veins, disseminated gold-bearing arsenian pyrite and arsenopyrite, stibnite, realgar, and orpiment. The barren milky quartz veins occur in the ore-controlling structures with an envelope of gold mineralization in the host rock consisting of disseminated gold-bearing arsenian pyrite and arsenopyrite and replacement-style quartz veinlets. Later drusy quartz, stibnite, realgar, and orpiment fill fractures and vugs on the periphery of gold mineralization. Petrography, microthermometry, laser Raman spectroscopy, and laser ablation inductively coupled plasma mass spectrometric (LA-ICP-MS) analyses of fluid inclusions are used to characterize the chemical evolution of ore fluids at Shuiyindong and Yata.
Etymology reveals much about the essence of a word. Science in German, Wissenschaft, is the art of observing whereas science in Chinese, koxue, is the study of classifying. Scientific observations, with the help of modern equipments, have made leaps and bounds in our century, but taxonomy seems irrelevant.
Classification can be science. The rise of the natural sciences in Europe could be traced back to Carl Linnaeus in 1750 when he used criteria of mutual exclusiveness to establish the taxonomy of living organisms. Unfortunately, this prerequisite in dividing and subdividing is not always appreciated, and a common practice in geology has been to "classify" basins through reference to incidental attributes. So, we have coastal basins, back-arc basins, extensionally rifted basins, uccessor basins, deep-sea basins, flysch basins, etc. These qualifications describe the geography, tectonic setting, principal stresses, orogenic chronology, depositional environment or sedimentary association of a basin, but these all could be different aspects of one and the same.
Our modern society has a constant need for raw materials and energy. An on-going effort in exploration and research is necessary, therefore, to discover and develop them. And, in this effort, it is better to appeal to geology than to rely on chance.
The first edition of this book was conceived in 1974 to provide a comprehensive text, covering modern and ancient environments, suitable for advanced university students, research workers and professional geologists. To cover all environments and facies with the authority of an active research worker, we formed a group of authors who knew each other well and shared a similar philosophical view. We could criticize, amend and integrate each other's contributions, while retaining individual styles and responsibility for each chapter.
Sedimentary exhalative (sedex) deposits account for more than 50 percent of the world’s zinc (Zn) and lead (Pb) reserves (Tikkanen, 1986) and furnish more than 25 percent of the world’s current production of these two metals and a significant amount of silver (Ag) (Goodfellow and Lydon, 2007). More than 129 deposits of this type have been recognized in sedimentary basins around the world (Leach and others, 2005b; Goodfellow and Lydon, 2007). A compilation by Taylor and others (2009) shows that deposits occur in 25 sedimentary basins, 7 of which contain more than 10 million metric tons (Mt) of combined Pb+Zn (figs. 1, 2). In order of decreasing endowment, these basins are the Mt. IsaMcArthur basins, Australia (7 deposits containing 112 Mt of Zn+Pb metal); Selwyn basin, Canada (17 deposits, 55 Mt); Brooks Range, Alaska, United States (3 deposits, 40 Mt); Kholodninskoye deposit, Russia (1 deposit, 23 Mt); Rajasthan basin, India (5 deposits, 20 Mt); Belt-Purcell basin, United States and Canada (1 deposit, 19 Mt); and Rhenish basin, Germany (2 deposits, 11 Mt) (fig. 1). <...>
