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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.earscirev.2009.10.011 Byline: Harald G. Dill Keywords: economic geology; mineral deposits; geology; mineralogy; classification scheme; spreadsheet Abstract: Economic geology is a mixtum compositum of all geoscientific disciplines focused on one goal, finding new mineral depsosits and enhancing their exploitation. The keystones of this mixtum compositum are geology and mineralogy whose studies are centered around the emplacement of the ore body and the development of its minerals and rocks. In the present study, mineralogy and geology act as x- and y-coordinates of a classification chart of mineral resources called the 'chessboard' (or 'spreadsheet') classification scheme. Magmatic and sedimentary lithologies together with tectonic structures (1-D/pipes, 2-D/veins) are plotted along the x-axis in the header of the spreadsheet diagram representing the columns in this chart diagram. 63 commodity groups, encompassing minerals and elements are plotted along the y -axis, forming the lines of the spreadsheet. These commodities are subjected to a tripartite subdivision into ore minerals, industrial minerals/rocks and gemstones/ornamental stones. Further information on the various types of mineral deposits, as to the major ore and gangue minerals, the current models and the mode of formation or when and in which geodynamic setting these deposits mainly formed throughout the geological past may be obtained from the text by simply using the code of each deposit in the chart. This code can be created by combining the commodity (lines) shown by numbers plus lower caps with the host rocks or structure (columns) given by capital letters. Each commodity has a small preface on the mineralogy and chemistry and ends up with an outlook into its final use and the supply situation of the raw material on a global basis, which may be updated by the user through a direct link to databases available on the internet. In this case the study has been linked to the commodity database of the US Geological Survey. The internal subdivision of each commodity section corresponds to the common host rock lithologies (magmatic, sedimentary, and metamorphic) and structures. Cross sections and images illustrate the common ore types of each commodity. Ore takes priority over the mineral. The minerals and host rocks are listed by their chemical and mineralogical compositions, respectively, separated from the text but supplemented with cross-references to the columns and lines, where they prevalently occur. A metallogenetic-geodynamic overview is given at the bottom of each column in the spreadsheet. It may be taken as the 'sum' or the ' mean' of a number of geodynamic models and ideas put forward by the various researchers for all the deposits pertaining to a certain clan of lithology or structure. This classical or conservative view of metallotects related to the common plate tectonic settings is supplemented by an approach taken for the first time for such a number of deposits, using the concepts of sequence stratigraphy. This paper, so as to say, is a 'launch pad' for a new mindset in metallogenesis rather than the final result. The relationship supergene-hypogene and syngenetic-epigenetic has been the topic of many studies for ages but to keep them as separate entities is often unworkable in practice, especially in the so-called epithermal or near-surface/shallow deposits. Vein-type and stratiform ore bodies are generally handled also very differently. To get these different structural elements (space) and various mineralizing processes (time) together and to allow for a forward modeling in mineral exploration, architectural elements of sequence stratigraphy are adapted to mineral resources. Deposits are geological bodies which need accommodation space created by the environment of formation and the tectonic/geodynamic setting through time. They are controlled by horizontal to subhorizontal reference planes and/or vertical structures. Prerequisites for the deposits to evolve are thermal and/or mechanical gradients. Thermal energy is for most of the settings under consideration deeply rooted in the mantle. A perspective on how this concept might work is given in the text by a pilot project on mineral deposits in Central Europe and in the spreadsheet classification scheme by providing a color-coded categorization into 1. mineralization mainly related to planar architectural elements, e.g. sequence boundaries subaerial and unconformities 2. mineralization mainly related to planar architectural elements, e.g. sequence boundaries submarine, transgressive surfaces and maximum flooding zones/surfaces) 3. mineralization mainly controlled by system tracts (lowstand system tracts transgressive system tracts, highstand system tracts) 4. mineralization of subvolcanic or intermediate level to be correlated with the architectural elements of basin evolution 5. mineralization of deep level to be correlated with the deep-seated structural elements. There are several squares on the chessboard left blank mainly for lack of information on sequence stratigraphy of mineral deposits. This method has not found many users yet in mineral exploration. This review is designed as an 'interactive paper' open, for amendments in the electronic spreadsheet version and adjustable to the needs and wants of application, research and training in geosciences. Metamorphic host rock lithologies and commodities are addressed by different color codes in the chessboard classification scheme. Article History: Received 6 July 2008; Accepted 23 October 2009

Heavy mineral analysis can play an important part in unraveling the extrabasinal (e.g., source area weathering) and intrabasinal processes (e.g., hydraulic processes) that influence the formation of clastic rocks. Various clastic (conglomerates, wackes, arenites, siltstones) and pyroclastic rocks (tuffs, ignimbrites, lahars) spanning the interval from the Upper Carboniferous through the Early Tertiary SE Germany (Bavaria) and the North German Basin were investigated for their transparent and opaque heavy minerals. The samples have been taken from drill cores, percussion holes and outcrops of various environments of deposition which are representative of a cross-section from the basin edge to the basin center (alluvial fan, braided streams, meandering to anastomosing fluvial drainage patterns, swamps, lakes, estuarine and nearshore-marine deposits). Routine heavy mineral analysis may be applied to heavy mineral separates in the grain size fraction from 0.020 mm to 0.200 mm, using heavy liquids of 2.95 g [ml.sup.-1]. The results furnish evidence that the strong points of this method lie in the fields of provenance analysis, paleoenvironmental analysis, and the study of volcanism and hydrothermal alteration. Routine heavy mineral analysis using the petrographic and ore microscope may successfully be combined with trace element analysis using ICPMS (e.g., REE, Th, U, Zr) and isotope studies (e.g., U, Pb). Radiometric age dating and the determination of the chemical composition of detrital apatite in late Paleozoic arenaceous rocks helped to pinpoint the type of source rocks and constrain the age of intrusion of the granites in the provenance area, from which the apatites were derived. This sedimentological method may be of interest to academicians and geologists working in the various fields of applied research alike (e.g., geoengineering, hydrogeology, exploration for hydrocarbons, uranium, coal and placer deposits). Keywords: Germany; heavy minerals; sediment geochemistry; provenance analysis; paleoenvironment; hydrothermal alteration

Aluminium phosphates and sulphates of the alunite supergroup (APS minerals) occur in a wide range of environments of formation covering the metamorphic, igneous and sedimentary realms. Supergene processes, including mineral dressing and dumping when sulphide ores are mined, as well as hypogene alteration are also responsible for the precipitation of APS minerals. In these environments, complex solid solution series (S.S.S.) can form. The general formula of these alunite minerals is [AB.sub.3] [([XO.sub.4]).sub.2][(OH).sub.6], where A is a large cation (Na, U, K, Ag, [NH.sub.4], Pb, Ca, Ba, Sr, REE). B sites are occupied by cations of the elements Al, Fe, Cu and Zn. In nature, the anion [([XO.sub.4]).sup.x-] is dominated by P and S. Mineral dressing and identification of APS minerals often needs a combination of highly sophisticated measures including Atterberg settling methods, XRD, DTA, TGA, TEM-EDX, SEM, EMPA and XRF. In sedimentary rocks APS minerals occur in various rocks and environments of deposition: calcareous, phosphoritebearing, argillaceous-carbonaceous, arenaceous, coal-bearing environments, in soils and paleosols, in saprolite (bauxites, laterites) and in calcareous-argillaceous sequences hosting Carlin-type SHDG deposits. In igneous rocks, APS minerals may be encountered mainly in acidic through intermediate pyroclastic, volcanic and subvolcanic rocks. They occur in barren volcanic rocks and porphyry-type intrusions that have sparked epithermal Au-Ag-base metal deposits, Au-Sb mineralization, APS-bearing argillite and alunite deposits in their immediate surroundings. Granitic and pegmatitic rocks are rarely host of supergene APS mineralization. During low-grade stage regional metamorphism, peraluminous parent rocks originating from a sedimentary or igneous protolith may also give rise to APS mineralization. Peraluminous parent rocks enriched in S and/or P are a prerequisite for the formation of APS minerals that are stable up to a temperature of 400 [degrees] C at moderately high fluid pressure of up to 1 kbar. The various APS mineralizations in nature occur in three zones; a fourth zone may be singled out when the enrichment of APS compounds in waste dumps, in acid mine drainage and during alum production is considered as part of the story. Zone I encompasses APS mineralization observed in metamorphic rocks of lowermost greenschist facies and igneous rocks that have undergone advanced argillic alteration with or without hydrothermal ore and non-metal mineralizations. Zone II following vertically upward in the earth crust is characterised by steam-heated, connate water- and ground water-related APS mineralization. This sort of APS mineralization forms close to the boundary between the vadose and phreatic hydraulic stockwork. The overlying zone III is confined to the topmost part of the vadose or infiltration zone. Its mineralization originated from meteoric waters and may be called supergene in the strict sense. Results obtained from the study of this kind of mineralization can directly be applied to artificial accumulation of APS compounds at the present-day surface. A combination of chemical measures such as S-O-H isotopes and REE variation together with experimentally based mineralogical data may be instrumental in the distinction of supergene and hypogene APS mineralization. This set of data may also assist in the assignment of APS mineralization either to hydrothermal magmatic or to steam-heated acid sulphate mineralizations. The K-bearing end members of the APS S.S.S. have proven to be an efficient tool to determine the age of formation of magmatic, weathering, diagenetic and alteration processes. APS minerals, however, can locally provide much more information to the origin of host and parent rocks than the rock-forming minerals themselves, which make up the host rocks of APS mineralization. [C] 2001 Elsevier Science B.V. All rights reserved. Keywords: alunite supergroup; sediments; igneous rocks; metamorphic rocks; geology; mineralogy