Mineralogy

The distribution of lithium, rubidium and caesium in igneous and sedimentary rocks

KEYWORD: detrital component characteristics; provenance analysis; Triassic. ABSTRACT: Triassic in the western Tabei uplift is detrital sedimentary. Based on the data of the conglomerate, sandstone framework components and heavy mineral to analyze the Triassic of research area, the result shows that the source rocks are metamorphic rocks, magmatic rocks and sedimentary rocks, whose sources come from Xiqiu Uplift and Luntai Uplift. The western of research area is magmatic and sedimentary rock deposit zone, where is mainly influenced by the Xiqiu Uplift. The middle part of research area is metamorphic and sedimentary rock deposit zone where is mainly influenced by the Xiqiu Uplift and Luntai Uplift. The eastern of research area is metamorphic, sedimentary and magmatic rock deposit zone where is mainly influenced by the Luntai Uplift. The proximal clastic deposits are mainly influenced by the hydrodynamic conditions, palaeohigh and tectonization, so provenance has the characteristics of region and multiple

PLATE 12. Geologic map of the Trinidad coal field._______________ In pocket FIGURE 18. Index map of the Trinidad coal field-_____________________ 19. Cokedale coal bed in the upper part of the Vermejo formation., 20. Frederick coal bed in the Raton formation,,______________ 143 21. Coal bed in the Raton formation intruded by an igneous sill__ 147 TABLES TABLE 1. Analyses of coals from the Trinidad coal field-_________-___--2. Classification of coals by rank_____________-__---_______--3. Total estimated

Highly refractory peridotites are defined here as peridotites more depleted in melt components than abyssal peridotite, i.e. peridotites with spinel showing Cr# (Cr/(Cr+Al) atomic ratio) higher than 0.6. These correspond to the type III peridotite defined by Dick and Bullen (1984) and are reported from forearc regions, such as Izu-Ogasawara, Mariana and Tonga trenches (e.g. Bloomer and Hawkins, 1983; Bloomer and Fisher, 1987; Ishii et al., 1992) and from the Kamuikotan belt, the central axial zone of Hokkaido, northern Japan (e.g. Katoh and Nakagawa, 1986; Makita and Arai, 1997). These peridotites are, however, not common in the upper mantle and their genesis has not been explained thoroughly. We discuss the genesis of highly refractory peridotite from three complexes, the Takadomari, Iwanaidake and Nukabira, in the Kamuikotan belt, Japan, and its bearing on the process of high-Mg andesite magma genesis. The Kamuikotan belt is a tectonic melange zone composed of metamorphic rocks, ultramafic rocks, greenstones and sedimentary rocks. The metamorphic rocks are of typical high-pressure/low-temperature type and ophiolitic rocks which recorded low-pressure ocean-floor metamorphism are distributed in the Horokanai area, northern part of the belt (Ishizuka et al., 1983). Ultramafic rocks form the basal member of the ophiolite in the northern part and are exposed as peridotite complexes of various size in the southern part of the Kamuikotan belt. They are generally in fault contact with surrounding Kamuikotan metamorphic rocks, sediments and mafic volcanic rocks (e.g. Niida and Katoh, 1978). The peridotite complexes mainly consist of harzburgite and dunite which suffered serpentinization to various extent. The Takadomari complex from the northern part, and the Iwanai-dake complex from the southern part of the belt consist of harzburgite, dunite and small amounts of orthopyroxenite. The Nukabira complex (southern part of the belt) consists of lherzolite and harzburgite with dunite and pyroxenites. Podiform chromitite deposits sometimes accompany dunite in the latter two complexes. Primary hydrous minerals are sometimes included in chromian spinel of the former two complexes. The Cr# of chromian spinel and Fo (forsterite) content of olivine in peridotites from the Takadomari complex are high (Cr#=0.64-0.92, Fo=91.9- 94.0), and are higher in dunite than in harzburgite on average. The Cr# and Fo are also high (Cr#=0.43-0.87, Fo=90.8-93.5) in the Iwanai-dake complex and have wider ranges (Cr#=0.18-0.86, Fo=89.0-93.2) in the Nukabira complex. The Cr# of spinel and Fo of olivine in dunite complexes are sometimes similar to or even lower than the values in harzburgite from Iwanai-dake and Nukabira complexes. The mineral chemistry of dunites in the Iwanai-dake and Nukabira complexes depends on their thickness within harzburgite or lherzolite bodies. Thicker dunite layers tend to show higher Cr# of chromian spinel and Fo content of olivine. In addition to this, there are clear systematic variations in lithology across dunite layers and surrounding peridotites. In the case of thick dunite layers, the Cr# of chromian spinel and the Fo content of olivine gradually increase from the surrounding peridotite to the central part of the dunite layer (Cr#>0.6 and Fo>91.5 in dunite). In contrast to this fact, these values in thin dunite layers are similar to the surrounding peridotite, lherzolite or harzburgite (Cr#=0.4- 0.6 and Fo=89-91). These values are generally lower in thinner dunite layers than in the thick ones compared at the center. The harzburgites and dunites in the Takadomari complex are interpreted to be a series of refractory residue after extraction of high-Mg andesite magma; partial melting of the fertile peridotite possibly occurred under hydrous conditions. Harzburgite and lherzolite are mostly simple residue in the Iwanai-dake and Nukabira complexes but their dunites are not simple residue because the Cr# and Fo content are not systematically higher in the dunite than in the harzburgite (e.g. Arai, 1987; 1994). The dunite may be produced by a reaction between wall peridotite and a melt formed at higher pressures (e.g. Quick, 1981; Fisk, 1986; Kelemen, 1990). The differences in thickness and mineral chemistry of dunite layers are due to the difference of the melt/wall peridotite volume ratio. Supplying a large amount of melt caused formation of thick dunite layers and generated high-Mg andesitic magma by the reaction process.

Petrographic, chemical (11 rock analyses), and age determinations (7 whole-rock K-Ar) were made on 27 “basement” well samples from 22 Florida counties north of Lake Okeechobee, and 3 additional K-Ar determinations were made on samples from Georgia. Most of the specimens are diabase, basalt, rhyolite, and basaltic and rhyolitic ash, generally fresh and unaltered, although contiguous sedimentary rocks may show considerable alteration. The igneous rocks are relatively young, the youngest age determined being 89.3 ± 2.2 m.y. (Late Cretaceous). Metamorphosed “granite” and “diorite” which may be altered arkosic sedimentary or igneous rocks gave older ages, up to 480 to 570(?) m.y. (Early Ordovician to Early[?] Cambrian). These older ages were found in two metamorphosed rocks from the central east coast of Florida, where other granitic metamorphic rocks have been reported; similar rock (undated) is present on the central west coast of Florida, and a Paleozoic age (middle Carboniferous) also was found for a metamorphic rock (hornblendite) from western Georgia. These older dated rocks have been considered to be part of a metamorphic basement intruded by the younger igneous rocks; however, hydrothermal alteration of igneous rocks may produce metamorphic textures, and sedimentary rocks may be “granitized” by contiguous igneous intrusives. No unambiguous Piedmont-type crystalline metamorphic rocks, such as mica schist, garnet schist, or sillimanife-andalusite-kyonite schist, have been found by drilling in Florida. The chemical analyses of these rocks per se have little correlative value because of the small size of available samples and the undoubted variability of the rock bodies represented. However, they apparently are the first and only such analyses made of Florida igneous-metamorphic rocks.

To determine the geographical distribution of dissolved inorganic phosphate (DIP) concentrations in stream water in Japan, 1,244 water samples were collected nationwide from watersheds unpolluted by any anthropogenic sources. DIP concentrations were logarithmically normally distributed, and showed a wide range from below the minimum limit of detection (1.5 μg · l-1) to 116 μg · l-1, with a median of 6.6 μg · l-1. The streams with higher concentrations (> 10 μg · l-1) were predominantly in the northern part of Ibaraki, the western parts of Saitama and Tokyo, the region from Ishikawa to Kyoto, and around the Shikoku and Kyusyu mountains. Those with lower concentrations (< 4 μg · l-1) were predominantly in central Hokkaido, Yamagata, the northern part of Gunma and the western part of the Chugoku district. A significant difference (P < 0.001) in DIP concentration was found among subsurface geologies. Watersheds with underlying sedimentary rocks had higher DIP concentrations in their stream water than those with underlying igneous and metamorphic rocks. Among sedimentary rocks, higher DIP concentrations were found in Paleozoic rocks than in Mesozoic and Cenozoic rocks. In igneous rocks, intermediate rocks (andesite) had higher DIP concentrations than acidic rocks (rhyorite and granite). The differences in DIP concentration among various types of igneous and metamorphic rocks coincided with the differences in phosphorus content obtained from the Geochemical Atlas of Japan. In other substances, DIP concentration positively correlated with SiO2 concentration except in Paleozoic and Mesozoic sedimentary rocks. These results indicate that DIP concentrations in stream water are partly controlled by phosphorus content and the mineral weathering of rock or soil.

Chemical balance of the Earth's crust

Major and trace element compositions (including REE) of mineral, thermal, mine and surface waters in SW Germany and implications for water–rock interaction

Sedimentary rocks form at low temperatures and pressures at the surface of Earth owing to deposition by water, wind, or ice. By contrast, igneous and metamorphic rocks form mainly below Earth's surface where temperatures and pressures may be orders of magnitude higher than those at the surface, although volcanic rocks eventually cool at the surface. These fundamental differences in the origin of rocks lead to differences in physical and chemical characteristics that distinguish one kind of rock from another. Sedimentary rocks are characterized particularly by the presence of layers, although layers are also present in some volcanic and metamorphic rocks, and by distinctive textures and structures. Many sedimentary rocks are also distinguished from igneous and metamorphic rocks by their mineral and chemical compositions and fossil content.

With the appearance of Petrology of the metamorphic rocks a longstanding wish of mine has been satisfied, namely the publication of a book on metamorphic rocks designed primarily for non-specialist students interested in the Earth sciences, and which would in this way form a companion to the existing books concerned with igneous and sedimentary rocks. Individual authors necessarily approach their subjects differently not only because of their varied interests but also because of major differences in subject matter. Igneous rocks of a volcanic nature can actually be observed in the making, albeit from a respectful distance, so it has been natural that in studying igneous rocks attention has been directed very much to laboratory investigations into the crystallisation of minerals from silicate melts. Similarly, with sedimentary rocks it is generally possible to gain critical insight into their origins by observing present conditions of sedimentation and by exploration of the oceans. Metamorphic processes, however, can never be observed directly. They are largely, therefore, matters of inference from evidence provided by the rocks themselves, backed by the accumulated evidence of field studies which may be regarded as case histories relating to given sets of geological conditions and events. Since both the nature of the rocks prior to metamorphism, and the conditions to which they are subjected, vary very widely, it is impossible to do justice to all in one book, and certainly in one of an introductory nature. This is perhaps the main justification for emphasis in the present case on selected topics which have prov ed of special interest to the Author in his teaching and research experience. Certainly from my own experience there are few pursuits more exciting and rewarding than studying crystalline rocks, ideally in the field in the first instance, and then petrographically, in order to determine their nature and to interpret their histories. Fortunately this is an experience in which anyone can share who is prepared to gain acquaintance with the minerals concerned and to learn the basic rules of petrographic interpretation.

This study tried to reveal relative surface denudation resistance and ranking by geologic types in the Southern Korean Peninsula using an 1:250,000 digital geologic map and ASTER GDEM. Among rock types such as igneous, sedimentary and metamorphic rocks, metamorphic rock showed the greatest resistance to surface denudation. The most resistant rock to surface denudation by geologic periods (e.g., the Precambrian, Paleozoic, Mesozoic and Cenozoic) was found from the Precambrian. Among the major tectonic settings in the Southern Korean Peninsula such as the Gyeonggi massif, Okcheon belt, Yeongnam massif, Gyeongsang basin and Pohang basin, the Okcheon belt indicated the greatest resistance. The most and least resistant rocks from the representative nine rocks in the Southern Korean Peninsula were Paleozoic limestone, and Cretaceous sedimentary rock and Cenozoic sedimentary rock, respectively. This study suggests that Paleozoic limestone, Cretaceous volcanic rock, Paleozoic sedimentary rock and Precambrian gneiss can be regarded as hard rocks with high elevation, steep slope and complicated relief, while soft rocks with low elevation, gentle slope and simple relief are Jurassic granite, Cretaceous sedimentary rock and Cenozoic sedimentary rock.

Mineral resources have been important to the Alaskan economy for hundreds of years. The Indians, Eskimos, and Aleuts used gold, copper, and other metals for jewelry, utensils, and weapons and as items of trade. The Russians, who arrived in 1728, showed only minor interest in minerals, focusing instead on furs. Nonetheless, records show that they mined iron ore on the Kenai Peninsula in 1793 and located gold there in 1834. In addition, the Russians were aware of copper-rich occurrences in the Copper River basin.The mining industry grew rapidly in Alaska after the United States purchased the region from Russia in 1867. By 1870, gold was being mined near Windham Bay and near Sitka, in southeastern Alaska. The first major hard-rock gold mining began at the Alaska-Juneau, Perseverance, and Treadwell mines near present-day Juneau following the discovery of placer gold near tidewater in 1880. Significant placer mining operations for gold soon spread northward into districts such as Fairban ks, Nome, Iditarod, and Circle.The exploitation of mineral resources, particularly gold, influenced the settlement and development of much of the state. Major cities such as Nome, Fairbanks, and Juneau, the capital, were originally built around early mining camps. By1996, more than 33 million oz of gold, as well as significant amounts of copper, lead, zinc, silver, and platinum-group elements, had been produced. In addition, there has been minor production of nickel. tin, mercury, and uraniumAlaska is presently experiencing a renaissance in mining on federal, state, private, and native lands. From 1990 to 1996, the minerals industly had an annual value of approximately $600 million, with a record 1 billion in 1996. Nearly 3,500 year-round jobs were directly attributed to the minerals industq. Looking forward into the twenty-fi rst centu1y, the outlook is even better. Major mines such as Heel Dog are in production. Recently completed exploration at the Red Dog sedimenta1y exhalative deposit has significantly expanded the reserve base and major mine expansion is contemplated. The Nixon Fork gold skarn deposit was put into production in 1995, with the first ore poured in November. The Greens Creek mine resumed production in late 1996, following renewed exploration and development of the volcanogenic massive sulfide deposit. The Fort Knox gold mine, near Fairbanks, is under construction and is scheduled to yield ore by late 1996. In southwest Alaska exploration success has yielded a significant gold resource at Donlin Creek. In addition, the Kensington-Jualin project is

Cadomian Magmatic Rocks from Zarand (SE Iran) Formed in a Retro-Arc Basin

Muarabungo Groundwater Basin,is locateed in Jambi and West Sumatra Province. Based on the four rainfall stations in Muaratebo, Dusun Rantau Pandan, Sungai Bengkal and Komplek Pengairan PU Station recorded in 2008 to 2011, the precipitation (ppt) in study area is 1799.09 mm/year. Value of evapotranspiration (Evpt) in the study area is equal to 1261.26 mm / year (70.1%). Groundwater Basin of Muarabungo has an infiltration debit of 2,516,791,750 m3 / year and run-off debit (Ro) of 798 042 638 m3 / year. Rock composer in the Muarabungo Groundwater Basin are dominated by Alluvium Deposition, Quaternary rocks, and also the surrounding areas are composed by igneous and metamorphic rocks. Aquifer with a good productvity can be found on Alluvium and sedimentary rocks such as tuff sandy, whereas region without exploitable groundwater are composed by igneous rocks and metamorphic rocks. Based on groundwater quality, Groundwater Basin is divided into 13 facies, namely Ca; Cl, ​​Mg; Cl, ​​Na + K, Cl, Ca; HCO3, Mg; HCO3, Na + K; HCO3, Ca; No. dominant type, Mg; Nodominan type, Na + K; No. dominant type, No. dominant type; Cl, ​​No. dominant type; HCO3, Nodominan type; SO4, and No. dominant type; No. dominant type. The result of water balance measurement in research area is used to show the areas for crisis and secure area. The water balance calculation and determining recharge and discharge areas are needed for developing conservation strategy.

Hf isotope study of Palaeozoic metaigneous rocks of La pampa province and implications for the occurrence of juvenile early Neoproterozoic (Tonian) magmatism in south-central Argentina