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Sample records for terrane puketeraki range

  1. Stratigraphic and structural implications of conodont and detrital zircon U—Pb ages from metamorphic rocks of the Coldfoot terrane, Brooks Range, Alaska

    Science.gov (United States)

    Moore, Thomas E.; Aleinikoff, John N.; Harris, Anita G.

    1997-01-01

    New paleontologic and isotopic data from the Emma Creek and Marion Creek schists of the Coldfoot terrane, Arctic Alaska superterrane, central Brooks Range, suggest Devonian and possibly younger ages of deposition for their sedimentary protoliths. Conodonts from marble of the Emma Creek schist, intruded by a roughly 392 Ma orthogneiss, are late Lochkovian (early Early Devonian, between about 408 and 396 Ma) and Silurian to Devonian at two other locations. Spherical to oblong detrital zircons from quartz-mica schist of the overlying Marion Creek schist yield mostly discordant U—Pb data suggestive of provenance ages of 3.0, 2.0-1.8, and 1.5-1.4 Ga; however, several euhedral grains of zircon from Marion Creek quartz-mica schist have concordant U—Pb ages from 370 to 360 Ma. The Marion Creek schist in our study area therefore is at least 26 m.y. younger than the Emma Creek schist. The age data imply that the protolith of the Emma Creek schist is age correlative with Devonian carbonate rocks in the Hammond and North Slope terranes, whereas the Marion Creek schist is age correlative with Upper Devonian and Lower Mississippian clastic sedimentary rocks of the Endicott Group in the Endicott Mountains terrane and shale and carbonate units in the De Long Mountains and Sheenjek River terranes. Consequently, tectonic models restoring the entire Coldfoot terrane beneath partly or wholly coeval rocks of the Hammond, Endicott Mountains, De Long Mountains, and Sheenjek River terranes of the Arctic Alaska superterrane require revision. Alternative reconstructions, including restoration of the Coldfoot terrane inboard of the Endicott Mountains terrane or outboard of the De Long Mountains and Sheenjek River terranes are plausible but require either larger amounts of shortening than previously suggested or indicate problematic facies relations.

  2. Stable Isotope Evidence for a Complex Fluid Evolution of the Northwestern British Columbia Coast Ranges Related to Terrane Accretion

    Science.gov (United States)

    Moertle, J.; Holk, G. J.

    2015-12-01

    Stable isotope geochemistry reveals a complex fluid evolution for the Western Metamorphic Belt (WMB), Coast Ranges Batholith (CRB), Central Gneiss Complex (CGC) and Coast Ranges Megalineament (CRM). These fluids are a product of a complex tectonic history related to terrane accretion that includes oblique convergence, metamorphism, magmatism, and orogenic collapse. From W-to-E, these fluid systems are as follows. High-pressure greenschist-to-amphibolite facies metasedimentary rocks of the WMB record variable mineral δD (-61 to -104‰) and δ18O (e.g., quartz +9.6 to +13.4‰) values with multiple minerals in apparent isotopic equilibrium (T ~ 450-550°C) suggest a low W/R system dominated by metamorphic fluids. Variable and non-equilibrium δD (-53 to -143‰) and δ18O (e.g., biotite +2.3 to +5.3‰) values from diorites of the Quottoon pluton affected by the ductile CRM suggest a complex evolution that involved both metamorphic and meteoric-hydrothermal fluids in this dextral shear zone; these results differ from those 300 km along strike to the north that documented only metamorphic fluids in the CRM (Goldfarb et al., 1988). Our data and those of Magaritz and Taylor (1976) from granulite facies metasediments of the CGC and plutons of the western CRB reveal homogeneous δD values (-62 to -78‰) and a restricted range of δ18O values (e.g., quartz +8.5 to +11.5‰) with all minerals in equilibrium at T > 570°C indicate a system dominated by magmatic fluids. Calculated whole-rock δ18O values (~ +7‰) for the Quottoon pluton and CRB intrusive rocks suggest a mantle origin for these magmas. Reinterpretation of very low δD (< -150‰) and quartz-feldspar δ18O pairs that display extreme disequilibrium (feldspar δ18O values as low as -5‰) from the Ponder pluton, eastern CRB, and Hazelton Group point reveals that the major meteoric-hydrothermal system that affected these rocks was related to Eocene detachment faulting along the Shames Lake fault system, a

  3. Tectonostratigraphic Terranes of the Circum-Pacific Region

    Science.gov (United States)

    Van der Voo, Rob

    Have you always wondered where the Tujunga, Baldy, and Cortez terranes might be located today, let alone during the Cretaceous or early Tertiary? This book may provide the answer, because in a little less than 600 pages for $32, which includes a marvelously produced color map of the entire Circum-Pacific region, one can read almost everything one wants to know about Earth's “ring of fire” and its displaced or suspect terranes. The printing, proofreading, illustrations, and references are all of the highest caliber, and the book is handsomely produced indeed. In page-by-page reading, I found maybe five typographical errors, but I will spare you the details.The contents of the book are divided into five parts, comprising principles or applications of terrane analysis and four unequally long parts on the four quadrants of the Pacific coasts. The northeast quadrant includes Alaska, the Canadian Cordillera, the U.S. coastal and Rocky Mountain belts, and Mexico; the northwest includes Kamchatka, northeast Asia, China, Japan, Taiwan, and the Philippines; the southwest section has articles on Australia, Malaya, Indonesia, New Zealand, and Antarctica; and the southeast comprises the Andes from Colombia to southern Chile. The book offers introductory text for beginning students of terrane analysis, as well as plenty of useful details and data for the expert who needs a handy reference volume. Subject matter or emphasis ranges from hydrocarbon generation in marginal basins, biogeography, paleomagnetism, geochronology, and structural and metamorphic aspects to stratigraphy and shows how the entire discipline of geological sciences is contributing to terrane analysis. There is literally something here for everyone in solid Earth science.

  4. Circum-North Pacific tectonostratigraphic terrane map

    Science.gov (United States)

    Nokleberg, Warren J.; Parfenov, Leonid M.; Monger, James W.H.; Baranov, Boris B.; Byalobzhesky, Stanislav G.; Bundtzen, Thomas K.; Feeney, Tracey D.; Fujita, Kazuya; Gordey, Steven P.; Grantz, Arthur; Khanchuk, Alexander I.; Natal'in, Boris A.; Natapov, Lev M.; Norton, Ian O.; Patton, William W.; Plafker, George; Scholl, David W.; Sokolov, Sergei D.; Sosunov, Gleb M.; Stone, David B.; Tabor, Rowland W.; Tsukanov, Nickolai V.; Vallier, Tracy L.; Wakita, Koji

    1994-01-01

    The companion tectonostratigraphic terrane and overlap assemblage of map the Circum-North Pacific presents a modern description of the major geologic and tectonic units of the region. The map illustrates both the onshore terranes and overlap volcanic assemblages of the region, and the major offshore geologic features. The map is the first collaborative compilation of the geology of the region at a scale of 1:5,000,000 by geologists of the Russian Far East, Japanese, Alaskan, Canadian, and U.S.A. Pacific Northwest. The map is designed to be a source of geologic information for all scientists interested in the region, and is designed to be used for several purposes, including regional tectonic analyses, mineral resource and metallogenic analyses (Nokleberg and others, 1993, 1994a), petroleum analyses, neotectonic analyses, and analyses of seismic hazards and volcanic hazards. This text contains an introduction, tectonic definitions, acknowledgments, descriptions of postaccretion stratified rock units, descriptions and stratigraphic columns for tectonostratigraphic terranes in onshore areas, and references for the companion map (Sheets 1 to 5). This map is the result of extensive geologic mapping and associated tectonic studies in the Russian Far East, Hokkaido Island of Japan, Alaska, the Canadian Cordillera, and the U.S.A. Pacific Northwest in the last few decades. Geologic mapping suggests that most of this region can be interpreted as a collage of fault-bounded tectonostratigraphic terranes that were accreted onto continental margins around the Circum-

  5. Relationships between the Brook Street Terrane and Median Tectonic Zone (Median Batholith) : evidence from Jurassic conglomerates

    International Nuclear Information System (INIS)

    Tulloch, A.J.; Kimbrough, D.L.; Landis, C.A.; Mortimer, N.; Johnston, M.R.

    1999-01-01

    U-Pb zircon ages of 237-180 Ma and c. 280 Ma of seven granitoid clasts from the Rainy River Conglomerate which lies within the eastern Median Tectonic Zone (Median Batholith) in Nelson, and the Barretts Formation of the Brook Street Terrane in Southland, constrain the depositional ages of both units to be no older than c. 180-200 Ma (Early Jurassic). The minimum age of the Rainy River Conglomerate is constrained by the 147 +2 -1 Ma (Latest Jurassic) emplacement age of the One Mile Gabbronorite (new name: previously western Buller Diorite). The ages and chemistry of five of the granitoid clasts are broadly compatible with derivation from rocks that are now represented by Triassic plutons of the Median Tectonic Zone (Median Batholith), although ages as young as 180 Ma are slightly outside the range of the latter as currently exposed in New Zealand. The age (273-290 Ma, 237 +/- 3 Ma) and chemistry of the other two clasts (one each from Rainy River Conglomerate and Barretts Formation) suggest derivation from the Brook Street Terrane. Similarity in stratigraphic age, depositional characteristics, granitoid clast ages and composition between Rainy River Conglomerate and Barretts Formation suggests that they are broadly correlative and collectively overlapped a combined Brook Street Terrane - Median Batholith (MTZ) before the Late Jurassic (147 +2 -1 Ma). Sedimentary overlap may also have continued across to Middle Jurassic conglomeratic strata in the Murihiku Terrane to the east of the Brook Street Terrane. A U-Pb zircon age of 261 +/- 2 Ma is reported for Pourakino Trondhjemite of the Brook Street Terrane. (author). 56 refs., 10 figs., 4 tabs

  6. Provenance analysis of the Late Paleozoic sedimentary rocks in the Xilinhot Terrane, NE China, and their tectonic implications

    Science.gov (United States)

    Han, Jie; Zhou, Jian-Bo; Wilde, Simon A.; Song, Min-Chun

    2017-08-01

    The Xilinhot Terrane is located in the eastern segment of the Central Asian Orogenic Belt in NE China, and is a key to a hotly debated issue on the Paleozoic tectonic evolution of this giant progenic belt. To constrain the tectonic evolution of the Xilinhot Terrane in the Late Paleozoic, we undertook zircon U-Pb dating and geochemical analyses of the Zhesi and Benbatu formations in the Suolun and Xi Ujimqin areas in the Xilinhot Terrane. Samples of the Benbatu Formation yield detrital zircon U-Pb ages ranging from 2659 Ma to 316 Ma, with four age populations at: 2659-1826 Ma, 1719-963 Ma, 590-402 Ma, and 396-316 Ma, whereas samples from the Zhesi Formation yield detrital zircon U-Pb ages ranging from 1967 Ma to 250 Ma, with four age populations at: 1967-1278 Ma, 971-693 Ma, 561-403 Ma, and 399-250 Ma. The age groups of both the Benbatu and Zhesi formations in the Xilinhot Terrane are similar to those in other parts of the Central Asian Orogenic Belt (CAOB). This evidence indicates that the Xilinhot Terrane is a microcontinent, and not an accretionary complex as previously thought. Furthermore, the youngest zircon grains in the Benbatu and Zhesi formations yield weighted mean 206Pb/238U ages of 322 ± 12 Ma (MSDW = 0.12, n = 4) and 257 ± 2.8 Ma (MSDW = 1.6, n = 8), respectively. Combined with fossil data, our new data suggest that the Benbatu and Zhesi formations in the Xilinhot Terrane were possibly deposited at ∼322 Ma and ∼257 Ma, respectively. Based on the provenance of the Carboniferous-Permian sandstones came from the blocks of NE China, we speculate that the Xilinhot Terrane is the western part of the Songliao block.

  7. Mafic rocks from Erinpura gneiss terrane in the Sirohi region ...

    Indian Academy of Sciences (India)

    (2011). (b) Lithostratigraphic map (adapted from Roy and Sharma 1999) showing occurrence of the Daba mafic body within Erinpura granite terrane around Sirohi (SW Rajasthan). Sampled section along NW–SE traverse is also shown. sector of the Delhi Fold Belt (DFB) represents a. Grenvillian age (∼1 Ga) arc terrane ...

  8. Lower precambrian of the Keivy Terrane, Northeastern Baltic Shield: A stratigraphic succession or a collage of tectonic sheets?

    Science.gov (United States)

    Balagansky, V. V.; Raevsky, A. B.; Mudruk, S. V.

    2011-03-01

    The Keivy Terrane in the northeastern Baltic Shield appreciably differs from the adjacent tectonic blocks. In the northwestern part of this terrane (the Serpovidny Range), an outlier of Paleoproterozoic supracrustal rocks called the Serpovidny structure is surrounded by Archean (?) Keivy high-alumina paraschists. As follows from structural and magnetic data, the Paleoproterozoic rocks are deformed into a tight sheath fold 8 × 2 km in size at the surface and 5 km in length along the sheath axis. Faults parallel to the boundaries of the layers and locally cutting them off at an acute angle are involved in folding as well. The outer boundaries of the Serpovidny structure are tectonic. This structure is complementary to a larger tectonic lens composed of the Keivy mica schists. It is concluded that all of the supracrustal rocks of the Serpovidny Range are in fact tectonic sheets and lenses deformed into sheath folds. The literature data show that kilometer-scale sheath folds occur throughout the Keivy paraschist belt and most likely were formed owing to thrusting of the Murmansk Craton onto the Keivy Terrane in the south-southwestern direction. Foliation and lineation related to thrusting have been established in the Archean silicic metavolcanics and peralkaline granites occupying the most part of the terrane. In contrast, the granitoids and gabbroanorthosites of the Archean basement, which form a block 90 × 20 km in the southwestern Keivy Terrane, were not affected by Paleoproterozoic deformation. In other words, a detached assembly of tectonic sheets composed of the upper and middle crustal rocks that underwent deformation at the initial stage of the Paleoproterozoic Lapland-Kola Orogeny and the Archean basement, which is free of this deformation, are distinguished. The depth of detachment is estimated at 20-25 km. The detachment of the upper and middle crust in the Keivy Terrane and its position in the structure of the Baltic Shield are consistent with a

  9. Unusual central Nevada geologic terranes produced by Late Devonian Antler orogeny and Alamo impact

    Science.gov (United States)

    Poole, Forrest G.; Sandberg, Charles

    2015-01-01

    This Special Paper is the product of nearly 25 years of geologic investigations. It is an exposition of two small areas, both less than 25 km east of the Mississippian Roberts Mountains allochthon, but each displaying a different, unique geologic terrane, previously undocumented in Nevada and perhaps in North America. One area, the Bisoni-McKay, at the south end of the Fish Creek Range, displays an olistostrome, shed eastward during the late Late Devonian (early Famennian) from a migrating Antler orogenic forebulge. The other, the Warm Springs–Milk Spring, at the south end of the Hot Creek Range, displays a deeper marine terrane affected by the early Late Devonian (middle Frasnian) Alamo impact.

  10. Cretaceous-Eocene provenance connections between the Palawan Continental Terrane and the northern South China Sea margin

    Science.gov (United States)

    Shao, Lei; Cao, Licheng; Qiao, Peijun; Zhang, Xiangtao; Li, Qianyu; van Hinsbergen, Douwe J. J.

    2017-11-01

    The plate kinematic history of the South China Sea opening is key to reconstructing how the Mesozoic configuration of Panthalassa and Tethyan subduction systems evolved into today's complex Southeast Asian tectonic collage. The South China Sea is currently flanked by the Palawan Continental Terrane in the south and South China in the north and the two blocks have long been assumed to be conjugate margins. However, the paleogeographic history of the Palawan Continental Terrane remains an issue of uncertainty and controversy, especially regarding the questions of where and when it was separated from South China. Here we employ detrital zircon U-Pb geochronology and heavy mineral analysis on Cretaceous and Eocene strata from the northern South China Sea and Palawan to constrain the Late Mesozoic-Early Cenozoic provenance and paleogeographic evolution of the region testing possible connection between the Palawan Continental Terrane and the northern South China Sea margin. In addition to a revision of the regional stratigraphic framework using the youngest zircon U-Pb ages, these analyses show that while the Upper Cretaceous strata from the Palawan Continental Terrane are characterized by a dominance of zircon with crystallization ages clustering around the Cretaceous, the Eocene strata feature a large range of zircon ages and a new mineral group of rutile, anatase, and monazite. On the one hand, this change of sediment compositions seems to exclude the possibility of a latest Cretaceous drift of the Palawan Continental Terrane in response to the Proto-South China Sea opening as previously inferred. On the other hand, the zircon age signatures of the Cretaceous-Eocene strata from the Palawan Continental Terrane are largely comparable to those of contemporary samples from the northeastern South China Sea region, suggesting a possible conjugate relationship between the Palawan Continental Terrane and the eastern Pearl River Mouth Basin. Thus, the Palawan Continental

  11. Emplacement kinematics of nepheline syenites from the Terrane ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Nepheline syenite plutons emplaced within the Terrane Boundary Shear Zone of the Eastern Ghats. Mobile Belt west of Khariar in northwestern Orissa are marked by a well-developed magmatic fabric including magmatic foliation, mineral lineations, folds and S-C fabrics. The minerals in the plutons, namely microcline ...

  12. The Apuseni Mountains, Romania, a Variscan Collage of Ordovician Gondwanan Terranes

    Science.gov (United States)

    Balintoni, I. C.; Balica, C.; Zaharia, L.; Chen, F.; Cliveti, M.; Hann, H. P.; Ghergari, L.

    2007-12-01

    The basement of the Apuseni Mountains, Romania, consists of three pre-Variscan terranes, sutured during an Early Variscan amalgamation around 351 Ma (Balintoni et al., this volume). The northern Someş Terrane (ST) is predominantly gneissic, while the southern Baia de Arieş Terrane (BAT) is dominated by the presence of large carbonate lenses, although metagranites and other types of orthogneisses can be found. These two terranes are sutured through the Biharia terrane, probably an accreted island arc. LA-ICP-MS datings on zircons extracted from orthogneisses and metagranites were performed in order to constrain the age of ST and BAT. A number of previously CL-imaged crystals were ablated at the China's University of Geosciences, Wuhan. From ST we dated an orthogneiss occurring in structurally lowermost position, a metatuff situated in the upper strongly retrogressed part and a twenty detrital crystal population sampled from a metasandstone. The 206Pb/238U apparent ages were projected using the weighted average plots.A magmatic crystallization age of 472.8±5.0 Ma (Upper Early Ordovician) resulted for one of the orthogneiss samples, besides several older ages at 505.7, 566.3 and 708.2 Ma corresponding to inherited cores. Another sample from the same rock appeared strongly affected by lead loss during a later thermotectonic event, most of the apparent ages grouping around 352±14 Ma. This age is similar with the age of the suture between ST and BT (Balintoni et al., this volume). The main zircon population of one metatuff sample furnished an averaged age of 423±7.2 Ma, also found in two additional samples, but their significance is obscure for the moment. Two primary magmatic ages arise at 464.2 and 473.8 Ma, an older value of 758.7 Ma corresponding to an inherited core. Detrital zircon ages range between 534.8 and 2596.8 Ma. The younger value represents an upper age constraint for the protolith age of ST-rocks. From BAT we dated the Lupşa metaporphyroid and the

  13. A new classification of the Turkish terranes and sutures and its implication for the paleotectonic history of the region

    Science.gov (United States)

    Moix, Patrice; Beccaletto, Laurent; Kozur, Heinz W.; Hochard, Cyril; Rosselet, François; Stampfli, Gérard M.

    2008-04-01

    phase (Late Triassic), thus suturing the Paleotethys. At that time, the Taurus plate developed foreland-type basins, filled with flysch-molasse deposits that locally overstepped the lower plate Taurus terrane and were deposited in the opening Neotethys to the south. These olistostromal deposits are characterized by pelagic Carboniferous and Permian material from the Paleotethys suture zone found in the Mersin mélange. The latter, as well as the Antalya and Mamonia domains are represented by a series of exotic units now found south of the main Taurus range. Part of the Mersin exotic material was clearly derived from the former north Anatolian passive margin (Huğlu-type series) and re-displaced during the Paleogene. This led us to propose a plate tectonic model where the Anatolian ophiolitic front is linked up with the Samail/Baër-Bassit obduction front found along the Arabian margin. The obduction front was indented by the Anatolian promontory whose eastern end was partially subducted. Continued slab roll-back of the Neotethys allowed Anatolian exotics to continue their course southwestward until their emplacement along the Taurus southern margin (Mersin) and up to the Beydağları promontory (Antaya-Mamonia) in the latest Cretaceous-Paleocene. The supra-subduction ocean opening at the back of the obduction front (Troodos-type Ocean) was finally closed by Eocene north-south shortening between Africa and Eurasia. This brought close to each other Cretaceous ophiolites derived from the north of Anatolia and those obducted on the Arabian promontory. The latter were sealed by a Maastrichtian platform, and locally never affected by Alpine tectonism, whereas those located on the eastern Anatolian plate are strongly deformed and metamorphosed, and affected by Eocene arc magmatism. These observations help to reconstruct the larger frame of the central Tethyan realm geodynamic evolution.

  14. Gondwanan/peri-Gondwanan origin for the Uchee terrane, Alabama and georgia: Carolina zone or Suwannee terrane(?) and its suture with Grenvillian basement of the Pine Mountain window

    Science.gov (United States)

    Steltenpohl, M.G.; Mueller, P.M.; Heatherington, A.L.; Hanley, T.B.; Wooden, J.L.

    2008-01-01

    The poorly known, suspect, Uchee terrane occupies a critical tectonic position with regard to how and when peri-Gondwanan (Carolina) and Gondwanan (Suwannee) terranes were sutured to Laurentia. It lies sandwiched between Laurentian(?) continental basement exposed in the Pine Mountain window and adjacent buried Gondwanan crust of the Suwannee terrane. The Uchee terrane has been proposed as both a septum of Piedmont rocks that once was continuous across the erosionally breached Pine Mountain window or part of the Carolina zone. To help resolve this issue, we conducted U-Pb (SHRIMP-RG) (sensitive high-resolution ion microprobe-reverse geometry) zircon studies and whole-rock isotopic analyses of principal metasedimentary and metaplutonic units. U-Pb ages for zircons from the Phenix City Gneiss suggest igneous crystallization at ca. 620 Ma, inheritance ca. 1000 to ca. 1700 Ma, and a ca. 300 Ma (Alleghanian) overprint recorded by zircon rims. Zircons from the metasedimentary/metavolcaniclastic Moffits Mill Schist yield bimodal dates at ca. 620 and 640 Ma. The 620 to 640 Ma dates make these rocks age-equivalent to the oldest parts of the Carolina slate belt (Virgilina and Savannah River) and strongly suggest a Gondwanan (Pan-African and/or Trans-Brasiliano) origin for the Uchee terrane. Alternatively, the Uchee terrane may be correlative with metamorphic basement of the Suwannee terrane. The ca. 300 Ma overgrowths on zircons are compatible with previously reported 295 to 288 Ma 40Ar/39Ar hornblende dates on Uchee terrane rocks, which were interpreted to indicate deep tectonic burial of the Uchee terrane contemporaneous with the Alleghanian orogeny recorded in the foreland. Temperature-time paths for the Uchee terrane are similar to that of the Pine Mountain terrane, indicating a minimum age of ca. 295 Ma for docking. In terms of tectono-metamorphic history of the Uchee terrane, it is important to note that no evidence for intermediate "Appalachian" dates (e.g, Acadian or

  15. Paleomagnetism of early Tertiary Alaska Peninsula rocks and implications for docking of peninsular terrane

    Energy Technology Data Exchange (ETDEWEB)

    Whitney, J.W.; Levinson, R.A.; Van Alstine, D.R.

    1985-04-01

    In order to refine the tectonic history of the peninsular terrane, Alaska, 22 sites (averaging 10 samples/site) in Paleogene Tertiary volcanic and sedimentary formations were sampled in the vicinity of Chignik, on the Pacific side of the Alaska Peninsula. Ten of the sites were drilled in the early Oligocene Meshik volcanics, ranging from andesite to basalt, and the other twelve sites were drilled in the late Eocene Tolstoi Formation sediments. Nine of the volcanic sites yielded stable R and/or N characteristic magnetization. Virtually no fine-grained, interbedded sediments occur with the Meshik volcanics at the sample sites, thus making reliable paleohorizontal determinations difficult. Although flow attitudes were tentatively used, it became rapidly apparent that problems of initial dip were insurmountable. As a result, all volcanic sites were considered unreliable for determining a meaningful paleomagnetic inclination. Upon thermal demagnetization, five of the sedimentary sites were judged stable. The mode of the paleomagnetic direction was calculated, D/I = 349.8/75.3(..beta..95 = 8.5), indicating no significant rotation. Uncertainties in structural corrections, however, may render only the inclination meaningful, which, from McFadden statistics yields, I = 75.9, ..cap alpha..95 = 7.9, corresponding to a paleolatitude of 63.3/sup 0/. This paleolatitude agrees with the expected value for the North American craton at 40 m.y. B.P., implying that the peninsular terrane had docked at at least that time.

  16. Chronologic constraints on the tectonic evolution of the Wilson Lake terrane of the Grenville Province, Canada

    DEFF Research Database (Denmark)

    Reno II, Barry Len; Korhonen, F.J.; Stout, J.H.

    the Grenville Orogen in North America. Many of these terranes record evidence of two orogenies: the Labradorian Orogeny at ca. 1710-1600 Ma, and the Grenville Orogeny at ca. 1080-980 Ma. The rocks in the Wilson Lake terrane are interpreted to have been subjected to peak pressures of ~0.95 GPa...... and ~930°C during the Labradorian Orogeny (Korhonen et al., in prep., Stability of sapphirine + quartz in the Wilson Lake terrane: calculated equilibria in NCKFMASHTO). The final amalgamation of the Wilson Lake terrane over the underlying Parautochthonous Belt is interpreted to have occurred during...... the Grenville Orogeny, when the terrane was subjected to a lower-T (500-350°C) overprinting. However, petrologic and chronologic evidence for the Grenville orogeny is limited in the Wilson Lake terrane. Here we present results from a monazite chemical (U-Th)-Pb chronologic study in order to provide constraints...

  17. Punta del Este terrane : a better knowledge

    International Nuclear Information System (INIS)

    Preciozzi, F.; Sanchez Bettucci, L; Basei, M.

    2002-01-01

    Field Punta del Este (TPE) is constituted by a series of gneisses and migmatites formed in the range of 1000 and 900 Ma, and have been intensely reworked during Rio Doce orogeny (ca. 600-500 Ma). This cortical segment represents high-grade metamorphic terrain, correlatable with complex gneiss Southwest Africa, particularly with Kibariáno Belt - Namaqualanos recognized in the southwestern portion of Africa (Namibia). U-Pb zircon ages in tonalite granitoids indicate values ​​between 1000 and 900 Ma and were interpreted as indicating the time of generation of these rocks. This should also be the age of high-grade metamorphism that affected a large part of the gneissic rocks of the region. Moreover, the anatectic related mobilized leucosomes ages of migmatites gave ca. 520-540 Ma, indicating that the metamorphic conditions (overlapping) during the Rio Doce orogeny reached at least the amphibolite facies. The metasedimentary cover TPE occurs in the vicinity of the towns of La Paloma Rocha. These are represented by a siliciclastic metasedimentary sequence represented by Rocha Formation. Despite the poly phase deformation and low grade metamorphism affecting this training, primary structures are common such as stratification plano-parallel, cross-bedding, hummock y and massive levels with gradational stratification

  18. Paleobiogeographic affinities of emsian (late early devonian) gastropods from farewell terrane (west-central Alaska)

    Science.gov (United States)

    Fryda, J.; Blodgett, R.B.

    2008-01-01

    The vast majority of Emsian gastropods from Limestone Mountain, Medfra B-4 quadrangle, west-central Alaska (Farewell terrane) belong to species with lecithotrophic larval strategy. The present data show that there is no significant difference in the paleobiogeo-graphic distribution of Emsian gastropod genera with lecithotrophic and planktotrophic larval strategies. Numerical analysis of the faunal affinities of the Emsian gastropod fauna from the Farewell terrane reveals that this terrane has much stronger faunal connections to regions like Variscan Europe, eastern Australia, and the Alexander terrane of southeast Alaska than to cratonic North America (Laurentia). The Canadian Arctic Islands is the only region of cratonic North America (Laurentia) that shows significant faunal affinities to the Emsian gastropod faunas of the Farewell terrane. The analysis also indicates a close faunal link between the Farewell and Alexander terranes. Published paleontological and geological data suggest that the Farewell and Alexander terranes represents tectonic entities that have been rifted away from the Siberia, Baltica, or the paleo-Pacific margin of Australia. The results of the present numerical analysis are not in conflict with any of these possibilities. However, the principle of spatial continuity of the wandering path prefers Siberia as the most probable "parental" paleocontinent for the derivation of both the Farewell and Alexander terranes. ?? 2008 The Geological Society of America.

  19. The basement of the Eastern Cordillera, Colombia: An allochthonous terrane in northwestern South America

    Science.gov (United States)

    Forero Suarez, A.

    The fault system of the Borde Llanero of Colombia represents the limit between two early Paleozoic geologic provinces: the Guiana Shield (Gondwana) to the east, and an allochthonous terrane — formerly a piece of the North American continent — to the west. The Baudó Range, the Western Cordillera, and the western flank of the Central Cordillera are the result of post-Jurassic accretion. In contrast the pre-Emsian metamorphic rocks of the eastern flank of the Central Cordillera, of the Eastern Cordillera of Colombia, and of the Mérida Andes correspond to an allochthonous terrane that was accreted to the north-western continental border of South America during the collision between North America and Gondwana in Silurian-Early Devonian times. Geochronologic and petrographic data indicate the presence of the Grenvillian granulite belt, represented by the Garzón-Sierra Nevada de Santa Marta belt. This belt is separated from the Guiana Shield by a magmatic tract which is parallel to the Borde Llanero of Venezuela and Colombia. The late Paleozoic regional metamorphism in the Northern Andes of Colombia occurred during Late Silurian-Early Devonian times. Since the late Emsian, a sedimentary cycle was initiated on this allochthonous basement. The faunal records of northwestern South America and the North American continent are indistinguishable for that time. This similarity clearly shows that both northwestern South America and the North American regions of the Appalachians and New Mexico belong to the same paleobiogeographic province. The faunal communication in this case supports the idea of the immediate neighborhood of the two continents.

  20. Yield of bedrock wells in the Nashoba terrane, central and eastern Massachusetts

    Science.gov (United States)

    DeSimone, Leslie A.; Barbaro, Jeffrey R.

    2012-01-01

    The yield of bedrock wells in the fractured-bedrock aquifers of the Nashoba terrane and surrounding area, central and eastern Massachusetts, was investigated with analyses of existing data. Reported well yield was compiled for 7,287 wells from Massachusetts Department of Environmental Protection and U.S. Geological Survey databases. Yield of these wells ranged from 0.04 to 625 gallons per minute. In a comparison with data from 103 supply wells, yield and specific capacity from aquifer tests were well correlated, indicating that reported well yield was a reasonable measure of aquifer characteristics in the study area. Statistically significant relations were determined between well yield and a number of cultural and hydrogeologic factors. Cultural variables included intended water use, well depth, year of construction, and method of yield measurement. Bedrock geology, topography, surficial geology, and proximity to surface waters were statistically significant hydrogeologic factors. Yield of wells was higher in areas of granites, mafic intrusive rocks, and amphibolites than in areas of schists and gneisses or pelitic rocks; higher in valleys and low-slope areas than on hills, ridges, or high slopes; higher in areas overlain by stratified glacial deposits than in areas overlain by till; and higher in close proximity to streams, ponds, and wetlands than at greater distances from these surface-water features. Proximity to mapped faults and to lineaments from aerial photographs also were related to well yield by some measures in three quadrangles in the study area. Although the statistical significance of these relations was high, their predictive power was low, and these relations explained little of the variability in the well-yield data. Similar results were determined from a multivariate regression analysis. Multivariate regression models for the Nashoba terrane and for a three-quadrangle subarea included, as significant variables, many of the cultural and

  1. Interpretation and tectonic implications of cooling histories: An example from the Black Mountains, Death Valley extended terrane, California

    Science.gov (United States)

    Holm, Daniel K.; Dokka, Roy K.

    1993-04-01

    In the Death Valley extended terrane of California, the Black Mountains have long been considered unique because they largely lack the miogeoclinal cover rocks characteristic of the surrounding ranges. Fission-track ages presented here are combined with published 40Ar/ 39Ar ages and used to construct cooling path envelopes for samples of Precambrian crystalline basement and Miocene plutonic rocks collected across the entire range. The cooling history reconstructions are used to differentiate between contrasting Miocene unroofing histories proposed for this range. Apatite and zircon fission-track ages from the southeastern portion of the range suggest unroofing occurred there at ˜ 13-8.5 Ma from temperatures well below 300°C. Cooling age data from the central Black Mountains indicate major unroofing at 8.5-6.0 Ma from temperatures greater than 300°C. Old cooling ages from directly beneath the highly extended Amargosa chaos rocks are consistent with the chaos rocks being part of an allochthonous slice that was tectonically transported from high crustal levels onto deeper crustal levels. Scenarios for the Miocene unroofing history of this range rely heavily on interpretations of the depth of emplacement of Miocene plutons in the core of the range. Thermochronologic and geobarometric data and thermal modeling of intrusion cooling suggest emplacement of an 11.6 Ma pluton into the crystalline core at a depth of 10-15 km. Both the cooling-age data and considerations of the local geology seem to preclude an unroofing history dominated by erosion of the overlying miogeoclinal section. The morphology of the cooling path envelopes constructed here are similar to those constructed for detachment fault terranes. The data are most consistent with unroofing involving tectonic denudation (10-15 km) along a single, westerly dipping detachment zone. Diachronous rapid cooling from southeast to northwest within the range is interpreted as a result of the lower plate undergoing

  2. Cenozoic extensional tectonics of the Western Anatolia Extended Terrane, Turkey

    International Nuclear Information System (INIS)

    Cemen, I; Catlos, E J; Gogus, O; Diniz, E; Hancer, M

    2008-01-01

    The Western Anatolia Extended Terrane in Turkey is located on the eastern side of the Aegean Extended Terrane and contains one of the largest metamorphic core complexes in the world, the Menderes massif. It has experienced a series of continental collisions from the Late Cretaceous to the Eocene during the formation of the Izmir-Ankara-Erzincan suture zone. Based our field work and monazite ages, we suggest that the north-directed postcollisional Cenozoic extension in the region is the product of three consecutive stages, triggered by three different mechanisms. The first stage was initiated about 30 Ma ago, in the Oligocene by the Orogenic Collapse the thermally weakened continental crust along the north-dipping Southwest Anatolian shear zone. The shear zone was formed as an extensional simple-shear zone with listric geometry at depth and exhibits predominantly normal-slip along its southwestern end. But, it becomes a high-angle oblique-slip shear zone along its northeastern termination. Evidence for the presence of the shear zone includes (1) the dominant top to the north-northeast shear sense indicators throughout the Menderes massif, such as stretching lineations trending N10E to N30E; and (2) a series of Oligocene extensional basins located adjacent to the shear zone that contain only carbonate and ophiolitic rock fragments, but no high grade metamorphic rock fragments. During this stage, erosion and extensional unroofing brought high-grade metamorphic rocks of the Central Menderes massif to the surface by the early Miocene. The second stage of the extension was triggered by subduction roll-back and associated back-arc extension in the early Miocene and produced the north-dipping Alasehir and the south-dipping Bueyuek Menderes detachments of the central Menderes massif and the north-dipping Simav detachment of the northern Menderes massif. The detachments control the Miocene sedimentation in the Alasehir, Bueyuek Menderes, and Simav grabens, containing high

  3. Cenozoic extensional tectonics of the Western Anatolia Extended Terrane, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Cemen, I; Catlos, E J [Boone Pickens School of Geology, Oklahoma State University, 105 Noble Research Center, Stillwater OK 74078 (United States); Gogus, O [University of Toronto, Department of Geology, Earth Sciences Centre, 22 Russell St. Toronto, Ontario, M5S 3B1 (Canada); Diniz, E [Occidental Oil and Gas Corporation, PO Box 22757, Houston TX 77227 (United States); Hancer, M [Pamukkale Universitesi, Muhendislik Fakultesi, Jeoloji Muh. Bolmu, Denizli, 20070 Turkey (Turkey)], E-mail: icemen@okstate.edu

    2008-07-01

    The Western Anatolia Extended Terrane in Turkey is located on the eastern side of the Aegean Extended Terrane and contains one of the largest metamorphic core complexes in the world, the Menderes massif. It has experienced a series of continental collisions from the Late Cretaceous to the Eocene during the formation of the Izmir-Ankara-Erzincan suture zone. Based our field work and monazite ages, we suggest that the north-directed postcollisional Cenozoic extension in the region is the product of three consecutive stages, triggered by three different mechanisms. The first stage was initiated about 30 Ma ago, in the Oligocene by the Orogenic Collapse the thermally weakened continental crust along the north-dipping Southwest Anatolian shear zone. The shear zone was formed as an extensional simple-shear zone with listric geometry at depth and exhibits predominantly normal-slip along its southwestern end. But, it becomes a high-angle oblique-slip shear zone along its northeastern termination. Evidence for the presence of the shear zone includes (1) the dominant top to the north-northeast shear sense indicators throughout the Menderes massif, such as stretching lineations trending N10E to N30E; and (2) a series of Oligocene extensional basins located adjacent to the shear zone that contain only carbonate and ophiolitic rock fragments, but no high grade metamorphic rock fragments. During this stage, erosion and extensional unroofing brought high-grade metamorphic rocks of the Central Menderes massif to the surface by the early Miocene. The second stage of the extension was triggered by subduction roll-back and associated back-arc extension in the early Miocene and produced the north-dipping Alasehir and the south-dipping Bueyuek Menderes detachments of the central Menderes massif and the north-dipping Simav detachment of the northern Menderes massif. The detachments control the Miocene sedimentation in the Alasehir, Bueyuek Menderes, and Simav grabens, containing high

  4. Cenozoic extensional tectonics of the Western Anatolia Extended Terrane, Turkey

    Science.gov (United States)

    Çemen, I.; Catlos, E. J.; Gogus, O.; Diniz, E.; Hancer, M.

    2008-07-01

    The Western Anatolia Extended Terrane in Turkey is located on the eastern side of the Aegean Extended Terrane and contains one of the largest metamorphic core complexes in the world, the Menderes massif. It has experienced a series of continental collisions from the Late Cretaceous to the Eocene during the formation of the Izmir-Ankara-Erzincan suture zone. Based our field work and monazite ages, we suggest that the north-directed postcollisional Cenozoic extension in the region is the product of three consecutive stages, triggered by three different mechanisms. The first stage was initiated about 30 Ma ago, in the Oligocene by the Orogenic Collapse the thermally weakened continental crust along the north-dipping Southwest Anatolian shear zone. The shear zone was formed as an extensional simple-shear zone with listric geometry at depth and exhibits predominantly normal-slip along its southwestern end. But, it becomes a high-angle oblique-slip shear zone along its northeastern termination. Evidence for the presence of the shear zone includes (1) the dominant top to the north-northeast shear sense indicators throughout the Menderes massif, such as stretching lineations trending N10E to N30E; and (2) a series of Oligocene extensional basins located adjacent to the shear zone that contain only carbonate and ophiolitic rock fragments, but no high grade metamorphic rock fragments. During this stage, erosion and extensional unroofing brought high-grade metamorphic rocks of the Central Menderes massif to the surface by the early Miocene. The second stage of the extension was triggered by subduction roll-back and associated back-arc extension in the early Miocene and produced the north-dipping Alaşehir and the south-dipping Büyük Menderes detachments of the central Menderes massif and the north-dipping Simav detachment of the northern Menderes massif. The detachments control the Miocene sedimentation in the Alaşehir, Büyük Menderes, and Simav grabens, containing high

  5. Ordovician graptolites from the basal part of the Palaeozoic transgressive sequence in the Karadere area, Zonguldak Terrane, NW Turkey

    Directory of Open Access Journals (Sweden)

    M. Cemal Göncüoglu

    2014-12-01

    Full Text Available The Karadere area to the east of Safranbolu in NW Anatolia is one of the very few localities in Turkey where the contact between the Cadomian basement and the Lower Palaeozoic transgressive succession is well exposed. The Ordovician graptolite Rhabdinopora flabelliformis (Eichwald ssp. was found in the basal part of the Bakacak Formation, indicating an Early to early Late Tremadocian age for the beginning of the Palaeozoic transgression in the Zonguldak terrane. A few metres above this occurrence, another horizon contains Paradelograptus cf. antiquus (T. S. Hall, which mainly ranges into the Late Tremadocian. Higher up in the Ordovician succession, a new graptolite bed confirms an early Darriwilian (Dw1 age for the middle part of the Karadere Formation with the occurrence of the biozonal index Levisograptus austrodentatus (Harris & Keble and the first record of Tetragraptus cor (Strandmark in the area. The palaeobiogeographic distribution of these Karadere fossils is in agreement with a peri-Gondwanan affinity of the Zonguldak Terrane of the Pontides, NW Anatolia, during the Early–Middle Ordovician.

  6. 40Ar/39Ar incremental-release ages of biotite from a progressively remetamorphosed Archean basement terrane in southwestern Labrador

    International Nuclear Information System (INIS)

    Dallmeyer, R.D.

    1982-01-01

    Gneisses within Archean basement terrane adjacent to the southwestern portion of the Labrador Trough were variably retrograded during a regional metamorphism of Grenville age (ca. 1000 Ma). Bioties from non-retrograded segments of the gneiss terrane record 40 Ar/ 39 Ar plateau and isochron ages which date times of cooling following an episode of the Kenoran orogeny (2376-2391 Ma). A suite of gneiss samples displaying varying degrees of retrograde alteration was collected across the Grenville metamorphic gradient. Bioties in these samples show no petrographic evidence of retrograde alteration, however they do record internally discordant 40 Ar/ 39 Ar age spectra. Although the extent of internal discordance is variable, the overall character of the release patterns is similar with younger apparent ages recorded in intermediate-temperature gas fractions. The total-gas dates range from 2257+-27 Ma (northwest) to 1751+-23 Ma (southeast), suggesting that variable quantities of radiogenic argon were lost from the Archean biotites during Grenville metamorphism. The 'saddle-shaped' nature of the discordant spectra indicates that argon loss was not accomplished through single-stage, volume diffusion processes. (orig./ME)

  7. Petrography and geochronology (U/Pb-Sm/Nd) the Passagem Granite, Pensamiento Granitoid Complex, Paragua Terrane, SW Amazon Craton, Mato Grosso, Brazil

    International Nuclear Information System (INIS)

    Jesus, Gisely Carmo de; Sousa, Maria Zelia Aguiar de; Ruiz, Amarildo Salina; Matos, Joao Batista de

    2010-01-01

    The Passagem granite includes stocks, plugs and dikes located in the Ricardo Franco hill - Vila Bela da Santissima Trindade region - state of Mato Grosso, central Brazil. The Passagem Granite is included in the Paragua terrane - SW Amazonian Craton. It consists of isotropic monzogranite, sienogranite and more rarely granodiorites with leucocratic dark gray to white color. These rocks range from hypidomorphic inequigranular to xenomorphic texture, fine to medium grained. Biotite is the only primary mafic present as essential phase and characterize an expanded slightly acid sequence formed by a sub-alkaline magmatism of high-potassium calc-alkaline, slightly peraluminous composition from arc magmatic tectonic environment during a post-collisional period. Mechanism of fractional crystallization of plagioclase, biotite, titanite, apatite and zircon associated with simultaneous crustal assimilation are suggested for the evolution of these rocks. The results support the hypothesis of a post-collisional magmatism in the Paragua terrane at 1284 +- 20 Ma corresponding to the crystallization age of the Passagem granite. This paper propose that Passagem Granite represents as an extension in Brazilian terrane of the Pensamiento Granitoid Complex. (author)

  8. Cebollati group, Nico Perez terrane: Definition and age

    International Nuclear Information System (INIS)

    Gaucher, C; Chemale, F.; Bossi, J.; Castiglioni, E.; Castiglioni, E.

    2010-01-01

    The Cebollati Group (Nico Perez Terrane) is formally erected in this work to include a meta sedimentary succession informally known as L as Teta s Complex . It is shown that the stratigraphy of the unit can be reconstructed at a number of sections between Minas and Zapicìn, using sedimentary structures and stromatolites as geo petal indicators. The basement of the group is represented by metamorphic rocks and granitoids of the La China Complex, for which a new U-Pb zircon age of 3.029 ± 54 Ma is presented. The Cebollatií Group comprises, from base to top, three formations: the Arroyo Ma lo Formation (sandstones and petites), Cerro de Valuable Formation (dolostones, partly stromatolitic, and p elites) and the Cerro del Diamant e Formation (p elites, BIF, quartz-pebble conglomerates and sandstones). The mean thickness of the Cebollatií Group is ca. 2 km, being greatest in the south and diminishing to the north. Available ages for the unit suggested a Neoarchean depositional age of 2.75 Ga. However, in this work 12 Nd model ages are presented for sedimentary rocks of the Cebollatí Group, which are mostly younger than 2.75 Ga, the youngest being 1.64 Ga. These ages call into question the Neoarchean age accepted for the unit, suggesting a Meso proterozoic depositional age. The evidence supporting both views is discussed in view of the new data. The minimum age of the Cebollatí Group is 1.3 Ga on the basis of carbon isotope ratios of dolostones and deformational ages consistently around 1.25 Ga

  9. Exhumation of (ultra-high-pressure terranes: concepts and mechanisms

    Directory of Open Access Journals (Sweden)

    C. J. Warren

    2013-02-01

    Full Text Available The formation and exhumation of high and ultra-high-pressure, (UHP, rocks of crustal origin appears to be ubiquitous during Phanerozoic plate subduction and continental collision events. Exhumation of (UHP material has been shown in some orogens to have occurred only once, during a single short-lived event; in other cases exhumation appears to have occurred multiple discrete times or during a single, long-lived, protracted event. It is becoming increasingly clear that no single exhumation mechanism dominates in any particular tectonic environment, and the mechanism may change in time and space within the same subduction zone. Subduction zone style and internal force balance change in both time and space, responding to changes in width, steepness, composition of subducting material and velocity of subduction. In order for continental crust, which is relatively buoyant compared to the mantle even when metamorphosed to (UHP assemblages, to be subducted to (UHP conditions, it must remain attached to a stronger and denser substrate. Buoyancy and external tectonic forces drive exhumation, although the changing spatial and temporal dominance of different driving forces still remains unclear. Exhumation may involve whole-scale detachment of the terrane from the subducting slab followed by exhumation within a subduction channel (perhaps during continued subduction or a reversal in motion of the entire plate (eduction following the removal of a lower part of the subducting slab. Weakening mechanisms that may be responsible for the detachment of deeply subducted crust from its stronger, denser substrate include strain weakening, hydration, melting, grain size reduction and the development of foliation. These may act locally to form narrow high-strain shear zones separating stronger, less-strained crust or may act on the bulk of the subducted material, allowing whole-scale flow. Metamorphic reactions, metastability and the composition of the subducted crust

  10. Pb-Nd Isotopes Indicate the Origin of Island Arc Terranes in the Early Paleozoic Pacific.

    Science.gov (United States)

    Münker

    2000-03-01

    The Takaka Terrane in New Zealand is one of the best exposed arc fragments of the early Paleozoic Australian-Antarctic convergent margin and constitutes one of the most outboard terranes of this margin in paleogeographic reconstructions. Pb-Nd isotope compositions of clinopyroxenes from the Cambrian Devil River Volcanics of the Takaka Terrane enable identification of the location of the terrane in the Paleo-Pacific Ocean. The Devil River Volcanics, a suite of primitive arc and back-arc rocks, are interbedded with the partly continent-derived Haupiri Group sediments. Extremely radiogenic Pb and unradiogenic Nd compositions in the arc rocks cannot be explained by assimilation of the Haupiri Group sediments or a continental basement of such a composition. Pb isotope compositions of the Takaka Terrane sediments are much less radiogenic and overlap with crustal compositions of the Lachlan Fold Belt in Australia, suggesting that both units are derived from one source, the Australian-Antarctic Pacific margin. Pb-Nd isotope compositions in the Devil River Volcanics reflect contamination of their mantle sources by subducted sediments derived from Archean provinces in either Antarctica or Laurentia. Both provinces show characteristically high 207Pb/204Pb500 and were located at the Pacific rim in the Cambrian. Mixing between mantle and Proterozoic continental material from present western South America or eastern Laurentia cannot explain the high 207Pb/204Pb500 in the New Zealand rocks. As in New Zealand, extreme spreads in Pb-Nd isotope compositions in other Cambrian volcano-sedimentary sequences in southeast Australia and Tasmania can be explained by the same model, suggesting that all these fragments originated along the Australian-Antarctic Gondwana margin. Pb isotope compositions of arc rocks, therefore, provide a new tool for terrane analysis in the early Paleozoic Pacific ocean.

  11. Simultaneous batholith emplacement, terrane/continent collision, and oroclinal bending in the Blue Mountains Province, North American Cordillera

    Czech Academy of Sciences Publication Activity Database

    Žák, J.; Verner, K.; Tomek, Filip; Holub, F. V.; Johnson, K.; Schwartz, J. J.

    2015-01-01

    Roč. 34, č. 6 (2015), s. 1107-1128 ISSN 0278-7407 Institutional support: RVO:67985831 Keywords : anisotropy of magnetic susceptibility (AMS) * North American Cordillera * orocline * pluton emplacement * terrane accretion * terrane/continent collision Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.750, year: 2015

  12. Zircon U-Pb ages and geochemistry of granitoids in the Truong Son terrane, Vietnam: Tectonic and metallogenic implications

    Science.gov (United States)

    Shi, Mei-Feng; Lin, Fang-Cheng; Fan, Wen-Yu; Deng, Qi; Cong, Feng; Tran, My-Dung; Zhu, Hua-Ping; Wang, Hong

    2015-04-01

    Truong Son terrane, one of the most important tectonic and metallogenic terranes in Indochina block, is composed of many volcano-plutonic complexes. Reported here is geochronological and geochemical data obtained from six different volcano-plutonic complexes. The new data reveals that the granite from the Hai Van complex is 438 Ma in age, and shows collision-related geochemical characteristics; whereas another five samples from five volcano-plutonic complexes present consistent emplacement and crystallization ages ranging from 261 to 242 Ma. Dien Bien granodiorite, Phia Bioc monzogranite and Dong Trau rhyolite display typical subduction-related calc-alkaline affinity (e.g., depletion in Nb-Ta and Ti and enrichment in Rb and La), while monzogranite from Song Ma complex displays collision-related shoshoniteseries and granites from Bengiang-Queson complex are related to post-collision calc-alkaline series. Based on these observations, in combination with the previous published geochronological data, we propose that at least four major stages of magmatic activities occurred during the Paleozoic and the Early Mesozoic through the Truong Son terrane: Ordovician-Silurian (420-470 Ma), Late Carboniferous-Early Permian (280-300 Ma), Late Permian to Mid-Triassic (245-270 Ma) and Middle-Late Triassic (200-245 Ma). These magmatic activities are not only attributed to the Tethyan Song Ma ocean southwestward subduction but also related to Paleo Tamky-Phuoc Son oceanic bidirectional subduction. Synthesized with regional metallogenic data, we identified three metallogenic epochs: (1) Late Carboniferous-Early Permian (280-300 Ma) arc-magmatic hydrothermal Cu-Au-Fe polymetallic metallogenic system related to the Tamky-Phuoc Son ocean north-dipping subduction; (2) Late Permian-Middle Triassic (245-280 Ma) arc-magmatic hydrothermal Cu-Au-Fe and orogenic W-Sn-Au polymetallic metallogenic system, which linked to both Paleo-Tethyan Song Ma ocean south-dipping subduction and Tamky

  13. Petrography and geochemistry of five granitic plutons from south central Uruguay: contribution to the knowledge of the Piedra Alta terrane

    International Nuclear Information System (INIS)

    Preciozzi, F.

    2005-01-01

    Granitoid rocks in south-central Uruguay are largely concentrated in three east-west trending metamorphic belts, known as (from south to north) the Montevideo Belt, the San José Belt and the Arroyo Grande Belt. These belts are separated from one another by intervening bands of gneisses of granitic composition. The whole assemblage, the gneisses as well as the metamorphic belts and their associated granites, collectively constitute the Piedra Alta Terrane. Five of these granite plutons, two from the San José Belt and three from the Arroyo Grande Belt, have been studied in some detail and the chemical composition of 86 samples (major elements as well as a selected suite of trace elements) have been determined. These data, as well as Rb-Sr isotopic data, show that these plutons are typically composite in nature, and that the various units range in age from 1900 Ma to 2500 Ma. The older ages were obtained from the main units of the plutons themselves whereas the younger ages are from late dykes which were emplaced into the plutons and which are clearly not related to them. The plutons are predominantly, but not exclusively, of calc-alkaline affinity and are typically synorogenic whereas the dykes are post-orogenic and are either calc-alkaline or alkaline in composition. These data have been incorporated into a tectonic model for the Piedra Alta Terrane which is considerably different from that heretofore proposed. The essential features of the geological history of the area are: 1) development of an older ''basement'' of granitic gneisses 2) deposition, upon or adjacent to this gneisses basement, of a typical Archean greenstone belt assemblage (no komatiites so far reported) 3) Paleo-proterozoic metamorphism, followed by syn-tectonic to post-tectonic intrusion of the plutonic rocks 4) major tectonic dislocation(s) associated with the Transamazonian orogeny 5) dyke emplacement (post-orogenic to anorogenic) following the Transamazonian orogeny

  14. Post-remagnetisation vertical axis rotation and tilting of the Murihiku Terrane (North Island, New Zealand)

    NARCIS (Netherlands)

    van de Lagemaat, Suzanna H.A.; Boschman, Lydian M.; Kamp, Peter J.J.; Langereis, Cor G.; van Hinsbergen, Douwe J.J.

    2018-01-01

    We collected palaeomagnetic sample sets from Murihiku Terrane, North Island to constrain its palaeolatitude during the Late Triassic–Jurassic. The majority of the sample host rocks were remagnetised. However, a few samples show a magnetic signal that possibly recorded a primary remanent

  15. Brunovistulian terrane (Bohemian Massif, Central Europe) from late Proterozoic to late Paleozoic: a review

    Czech Academy of Sciences Publication Activity Database

    Kalvoda, J.; Bábek, O.; Fatka, O.; Leichmann, J.; Melichar, R.; Nehyba, S.; Špaček, Petr

    2008-01-01

    Roč. 97, č. 3 (2008), s. 497-518 ISSN 1437-3254 Institutional research plan: CEZ:AV0Z30120515 Keywords : Bohemian Massif * Brunovistulian terrane * Variscan orogeny Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.970, year: 2008

  16. New Insights from Seismic Imaging over the Youanmi Terrane, Western Australia

    Science.gov (United States)

    Ahmadi, Omid; Juhlin, Christopher

    2014-05-01

    The Youanmi terrane is located in the central parts of the Yilgarn craton, Western Australia, an Archean granite-greenstone unit containing numerous mineral deposits such as gold, base metals, nickel, uranium and gemstones. The terrane is surrounded by the Kalgoorlie and Narryer terranes to the east and west, respectively. To the southwest it is bounded by the South West terrane. In order to study the transitions between the Youanmi terrane and the surrounding terranes, as well as identifying potential mineral rich areas, the Geological Survey of Western Australia acquired three deep crustal 2D seismic profiles with a total length of about 700 km in 2010. Correlated record lengths of 20 seconds allow the deep structure of the crust to be investigated with the data, down to Moho depths and greater. Initial processing using a conventional 2D flow show a highly reflective crust with several interesting features. We have now reprocessed the data following mainly the previous processing flow, but with a focus on the shallower crust, less than 10 seconds (about 27 km). Due to the complex geology in the region, 3D aspects of the structures need to be considered in the data processing. Therefore, we investigated the effect of cross-dip corrections to the data. The cross-dip correction has two advantages; (i) reflections are more coherent and enhanced after the correction and (ii) the orientation and dip angle of the geological structures of the corresponding reflections can be identified in the cross-line direction. Where the profiles intersect each other sparse 3D processing can be performed. First arrival travel-time tomography was also tested on parts of the dataset. Travel-time inversion may provide better velocity models at shallow depths than standard reflection seismic processing provides. Preliminary results show that the travel-time tomography has a depth of investigation of about 1 km, a depth that is of interest for mining purposes. Therefore, the tomography

  17. The age and composition of the pre-Cenozoic basement of the Jalisco Block: implications for and relation to the Guerrero composite terrane

    Science.gov (United States)

    Valencia, Victor A.; Righter, Kevin; Rosas-Elguera, Jose; López-Martínez, Margarita; Grove, Marty

    2013-09-01

    The Jalisco Block is thought to be part of the Guerrero terrane, but the nature and age of the underlying crystalline basement are largely unknown. We have collected a suite of schists, granitoids, and weakly metamorphosed marine sediments from various parts of the Jalisco Block including Atenguillo and Ameca, Mascota and San Sebastián, Cuale, Puerto Vallarta, Punta Mita, Yelapa, and Tomatlán. The schists range in age from 135 to 161 Ma, with many exhibiting Proterozoic and Phanerozoic zircon ages. The granitoids range in age from 65 to 90 Ma, and are calc-alkaline compositionally—similar to granitoids from the Puerto Vallarta and Los Cabos batholiths. The Jalisco granitoids also experienced similar uplift rates to granitoids from the regions to the north and south of the Jalisco Block. The marine sediments yield a maximum depositional age of 131 Ma, and also contain a significant zircon population with ages extending back to the Archean. Granitoids from this study define two age groups, even after the effects of thermal resetting and different closure temperatures are considered. The 66.8-Ma silicic ash flow tuff near Union de Tula significantly expands the extent of this Cretaceous-Paleocene age ash flow tuff unit within the Jalisco Block, and we propose calling the unit "Carmichael silicic ash flow tuff volcanic succession" in honor of Ian Carmichael. The ages of the basement schists in the Jalisco Block fully overlap with the ages of terranes of continental Mexico, and other parts of the Guerrero terrane in the south, confirming the autochthonous origin of the Jalisco Block rather than exotic arc or allochthonous origin. Geologic data, in combination with geochronologic and oxygen isotopic data, suggest the evolution of SW Mexico with an early 200-1,200-Ma passive margin, followed by steep subduction in a continental arc setting at 160-165 Ma, then shallower subduction by 135 Ma, and finally, emplacement of granitoids at 65-90 Ma.

  18. Lithospheric electrical structure of the middle Lhasa terrane in the south Tibetan plateau

    Science.gov (United States)

    Liang, Hongda; Jin, Sheng; Wei, Wenbo; Gao, Rui; Ye, Gaofeng; Zhang, Letian; Yin, Yaotian; Lu, Zhanwu

    2018-04-01

    The Lhasa terrane in southern Tibetan plateau is a huge tectono-magmatic belt and an important metallogenic belt. Its formation evolution process and mineralization are affected by the subduction of oceanic plate and subsequent continental collision. However, the evolution of Lhasa terrane has been a subject of much debate for a long time. The Lithospheric structure records the deep processes of the subduction of oceanic plate and continental collision. The magnetotelluric (MT) method can probe the sub-surface electrical conductivity, newly dense broadband and long period magnetotelluric data were collected along a south-north trending profile that across the Lhasa terrane at 88°-89°E. Dimensionality analyses demonstrated that the MT data can be interpreted using two-dimensional approaches, and the regional strike direction was determined as N110°E.Based on data analysis results, a two-dimensional (2-D) resistivity model of crust and upper mantle was derived from inversion of the transverse electric mode, transverse magnetic mode and vertical magnetic field data. Inversion model shows a large north-dipping resistor that extended from the upper crust to upper mantle beneath the Himalaya and the south of Lhasa Terrane, which may represent the subducting Indian continental lithosphere. The 31°N may be an important boundary in the Lhasa Terrane, the south performs a prominent high-conductivity anomaly from the lower crust to upper mantle which indicates the existence of asthenosphere upwelling, while the north performs a higher resistivity and may have a reworking ancient basement. The formation of the ore deposits in the study area may be related to the upwelling of the mantle material triggered by slab tearing and/or breaking off of the Indian lithosphere, and the mantle material input also contributed the total thickness of the present-day Tibetan crust. The results provide helpful constrains to understand the mechanism of the continent-continent collision and

  19. Origin and tectonic evolution of early Paleozoic arc terranes abutting the northern margin of North China Craton

    Science.gov (United States)

    Zhou, Hao; Pei, Fu-Ping; Zhang, Ying; Zhou, Zhong-Biao; Xu, Wen-Liang; Wang, Zhi-Wei; Cao, Hua-Hua; Yang, Chuan

    2017-12-01

    The origin and tectonic evolution of the early Paleozoic arc terranes abutting the northern margin of the North China Craton (NCC) are widely debated. This paper presents detrital zircon U-Pb and Hf isotopic data of early Paleozoic strata in the Zhangjiatun arc terrane of central Jilin Province, northeast (NE) China, and compares them with the Bainaimiao and Jiangyu arc terranes abutting the northern margin of the NCC. Detrital zircons from early Paleozoic strata in three arc terranes exhibit comparable age groupings of 539-430, 1250-577, and 2800-1600 Ma. The Paleoproterozoic to Neoarchean ages and Hf isotopic composition of the detrital zircons imply the existence of the Precambrian fragments beneath the arc terranes. Given the evidences from geology, igneous rocks, and detrital zircons, we proposed that the early Paleozoic arc terranes abutting the northern margin of the NCC are a united arc terrane including the exotic Precambrian fragments, and these fragments shared a common evolutionary history from Neoproterozoic to early-middle Paleozoic.

  20. Crustal structure of norther Oaxaca terrane; The Oaxaca and caltepec faults, and the Tehuacan Valley. A gravity study.

    Science.gov (United States)

    Campos-Enriquez, J. O.; Alatorre-Zamora, M. A.; Ramón, V. M.; Belmonte, S.

    2014-12-01

    Northern Oaxaca terrane, southern Mexico, is bound by the Caltepec and Oaxaca faults to the west and east, respectively. These faults juxtapose the Oaxaca terrane against the Mixteca and Juarez terranes, respectively. The Oaxaca Fault also forms the eastern boundary of the Cenozoic Tehuacan depression. Several gravity profiles across these faults and the Oaxaca terrane (including the Tehuacan Valley) enables us to establish the upper crustal structure of this region. Accordingly, the Oaxaca terrane is downward displaced to the east in two steps. First the Santa Lucia Fault puts into contact the granulitic basamental rocks with Phanerozoic volcanic and sedimentary rocks. Finally, the Gavilan Fault puts into contact the Oaxaca terrane basement (Oaxaca Complex) into contact with the volcano-sedimentary infill of the valley. This gravity study reveals that the Oaxaca Fault system gives rise to a series of east tilted basamental blocks (Oaxaca Complex?). A structural high at the western Tehuacan depression accomadates the east dipping faults (Santa Lucia and Gavilan faults) and the west dipping faults of the Oaxaca Fault System. To the west of this high structural we have the depper depocenters. The Oaxaca Complex, the Caltepec and Santa Lucia faults continue northwestwards beneath Phanerozoic rocks. The faults are regional tectonic structures. They seem to continue northwards below the Trans-Mexican Volcanic Belt. A major E-W to NE-SW discontinuity on the Oaxaca terrane is inferred to exist between profiles 1 and 2. The Tehuacan Valley posses a large groundwater potential.

  1. Age/isotopic characterisation of the Waipapa Group in Northland and Auckland, New Zealand, and implications for the status of the Waipapa Terrane

    International Nuclear Information System (INIS)

    Adams, C.J.; Maas, R.

    2004-01-01

    Rb-Sr ages of low-grade metasediments of the Waipapa Group (probable Permian-Jurassic) of Northland and Auckland range from Late Triassic (c. 209-217 Ma) to Middle Jurassic (c. 164-174 Ma), reflecting deformation and metamorphism during the Rangitata Orogeny. K-Ar ages indicate Middle Jurassic (c. 165-175 Ma) uplift and cooling of the western Omahuta-Puketi Forest block, and later, Middle-Late Jurassic (c. 150-160 Ma) cooling of the Helena Bay to Hunua Ranges eastern coastal block. In the intervening Western Bay of Islands block, there is evidence of local Early Cretaceous (c. 135 Ma) metamorphism. Rb-Sr whole-rock isochron age (t) and initial 87 Sr/ 86 Sr ratio (i) data support the assignment of Waipapa Group of the westernmost, Omahuta-Puketi block to the Caples Terrane. The remaining data have a consistent (t)-(i) signature, with (i) values 0.7039-0.7049, unlike Permian-Cretaceous Torlesse Supergroup metasediments with more radiogenic (i) values, typically >0.7060. They thus support the retention of a separate, Waipapa Terrane which continues southwards through central North Island to the Kaimanawa Ranges, and probably to Kapiti Island, and schist equivalents in eastern Marlborough. (author). 62 refs., 5 figs., 3 tabs

  2. Modulation of Crustal Faulting in the Crescent Terrane by the Volume of Underthrust Accretionary Complex Along the Washington Cascadia Forearc

    Science.gov (United States)

    Brocher, T. M.

    2017-12-01

    Amphibious seismic experiments reveal widespread underthrusting of Cascadia accretionary rocks beneath basalts of the Crescent terrane, a large igneous province in the Washington forearc. Along margin variations in the volumes of the underthrust accretionary rocks appear to modulate the faulting within the overlying Crescent terrane, which hosts nearly all of the seismicity in the Washington forearc: the underlying accretionary rocks appear to deform aseismically. The underthrusting and underplating of large volumes of accretionary rocks on the Olympic Peninsula have uplifted and completely eroded a significant volume of the Crescent terrane, affecting the load-bearing strength of the forearc. I propose that as a consequence, the remnant Crescent terrane is actively deforming, as evidenced by the concentrated seismicity within it beneath Puget Lowland. This seismicity, focal mechanisms, fault geometries, and seismic tomography indicate that clockwise rotation and north-south compression of the forearc crust inferred from GPS data are accommodated by numerous thrust and strike slip faults in the remnant Crescent terrane. In addition to the spatial association between the erosion of the Crescent terrane on the Olympic Peninsula and the crustal faulting beneath Puget Lowland, support for the interpretation that the two are related also derives from the temporal coincidence between the mid to late Miocene uplift of the Crescent terrane on the peninsula and the mid-Miocene initiation of the thrust faulting in the lowland. In contrast, the underthrusting and underplating of lower volumes of accretionary rocks in the Washington forearc south of the Olympic Peninsula correlate with lower rates of crustal seismicity. These lower volumes of accretionary rocks have not caused the removal of a significant fraction of the Crescent terrane, resulting in a stronger, more structurally coherent Crescent terrane that deforms at lower rate than to the north.

  3. Late Triassic Porphyritic Intrusions And Associated Volcanic Rocks From The Shangri-La Region, Yidun Terrane, Eastern Tibetan Plateau: Implications For Adakitic Magmatism And Porphyry Copper Mineralization

    Science.gov (United States)

    Wang, B.; Zhou, M.; Li, J.; Yan, D.

    2011-12-01

    The Yidun terrane, located on the eastern margin of the Tibetan plateau, has been commonly considered to be a Triassic volcanic arc produced by subduction of the Ganzi-Litang oceanic lithosphere. The Yidun terrane is characterized by numerous arc-affinity granitic intrusions located along a 500-km-long, north-south-trending belt. Among these granitic bodies, several small porphyritic intrusions in the southern segment of the terrane (Shangri-La region) are associated with large porphyry copper deposits. These porphyritc intrusions are composed of diorite and quartz diorite, and spatially associated with andesites and dacites. LA-ICP-MS zircon U-Pb ages of the intrusions range from 230 to 215 Ma. The andesites and dacites are intercalated with slates and sandstones and have ages of around 220 Ma. The intrusive and volcanic rocks have SiO2 contents from 56.6 to 67.1 wt.%, Al2O3 from 14.2 to 17.4 wt.% and MgO from 1.9 to 4.2 wt.%. They show significant negative Nb-Ta anomalies on primitive mantle-normalized spidergrams. They have high La/Yb (13-49) ratios with no prominent Eu anomalies. All the rocks have high Sr (258-1980 ppm), and low Y (13-21 ppm) with high Sr/Y ratios (29-102). The geochemical features indicate that both the volcanic rocks and porphyritic intrusions were derived from adakitic magmas. They have similar initial 87Sr/86Sr ratios (0.7058 to 0.7077) and ɛNd (-1.88 to -4.93) values, but can be further divided into two groups: high silica (HSA) and low silica adakitic rocks (LSA). The HSA, representing an early stage of magmatism (230 to 215 Ma), were derived from oceanic slab melts with limited interaction with the overlying mantle wedge. At 215 Ma, more extensive interaction resulted in the formation of LSA. We propose that HSA were produced by flat subduction leading to melting of oceanic slab, whereas subsequent slab break-off caused the significant interaction between slab melts and the mantle wedge and thus the generation of the LSA. Compared with

  4. Thermochronology of the Sulu ultrahigh-pressure metamorphic terrane: Implications for continental collision and lithospheric thinning

    Science.gov (United States)

    Liu, Li-Ping; Li, Zheng-Xiang; Danišík, Martin; Li, Sanzhong; Evans, Noreen; Jourdan, Fred; Tao, Ni

    2017-08-01

    The thermal history of the Dabie-Sulu orogenic belt provides important constraints on the collision process between the South China and North China blocks during the Mesozoic, and possible lithospheric thinning event(s) in the eastern North China Block. This study reports on the thermal evolution of the Sulu ultrahigh-pressure metamorphic (UHP) terrane using zircon U-Pb geochronology and multiple thermochronology methods such as mica and hornblende 40Ar/39Ar, zircon and apatite fission track, and zircon and apatite (U-Th)/He dating. 40Ar/39Ar and zircon (U-Th)/He data show that the UHP terrane experienced accelerated cooling during 180-160 Ma. This cooling event could be interpreted to have resulted from extensional unroofing of an earlier southward thrusting nappe, or, more likely, an episode of northward thrusting of the UHP rocks as a hanging wall. A subsequent episode of exhumation took place between ca. 125 Ma and 90 Ma as recorded by zircon (U-Th)/He data. This event was more pronounced in the northwest section of the UHP terrane, whereas in the southeast section, the zircon (U-Th)/He system retained Jurassic cooling ages of ca. 180-160 Ma. The mid-Cretaceous episode of exhumation is interpreted to have resulted from crustal extension due to the removal of thickened, enriched mantle. A younger episode of exhumation was recorded by apatite fission track and apatite (U-Th)/He ages at ca. 65-40 Ma. Both latter events were linked to episodic thinning of lithosphere along the Sulu UHP terrane in an extensional environment, likely caused by the roll-back of the Western Pacific subduction system.

  5. Low Angle Contact Between the Oaxaca and Juárez Terranes Deduced From Magnetotelluric Data

    Science.gov (United States)

    Arzate-Flores, Jorge A.; Molina-Garza, Roberto; Corbo-Camargo, Fernando; Márquez-Ramírez, Víctor

    2016-10-01

    We present the electrical resistivity model along a profile perpendicular to the Middle America trench in southern Mexico that reveals previously unrecognized tectonic features at upper to mid-crustal depths. Our results support the hypotheses that the upper crust of the Oaxaca terrane is a residual ~20 km thick crust composed by an ~10 km thick faulted crustal upper layer and an ~10 km thick hydrated and/or mineralized layer. Oaxaca basement overthrust the younger Juárez (or Cuicateco) terrane. The electrical resistivity model supports the interpretation of a slab subducting at a low angle below Oaxaca. Uplift in the Oaxaca region appears to be related to fault reactivation induced by low angle subduction. In the Juárez terrane, isostatic forces may contribute to uplift because it is largely uncompensated. In the Sierra Madre del Sur, closer to the coast, uplift is facilitated by slab-dehydration driven buoyancy. Both gravity and resistivity models are consistent with a thinned upper crust in the northeast end of the profile.

  6. Circum-Pacific accretion of oceanic terranes to continental blocks: accretion of the Early Permian Dun Mountain ophiolite to the E Gondwana continental margin, South Island, New Zealand

    Science.gov (United States)

    Robertson, Alastair

    2016-04-01

    Accretionary orogens, in part, grow as a result of the accretion of oceanic terranes to pre-existing continental blocks, as in the circum-Pacific and central Asian regions. However, the accretionary processes involved remain poorly understood. Here, we consider settings in which oceanic crust formed in a supra-subduction zone setting and later accreted to continental terranes (some, themselves of accretionary origin). Good examples include some Late Cretaceous ophiolites in SE Turkey, the Jurassic Coast Range ophiolite, W USA and the Early Permian Dun Mountain ophiolite of South Island, New Zealand. In the last two cases, the ophiolites are depositionally overlain by coarse clastic sedimentary rocks (e.g. Permian Upukerora Formation of South Island, NZ) that then pass upwards into very thick continental margin fore-arc basin sequences (Great Valley sequence, California; Matai sequence, South Island, NZ). Field observations, together with petrographical and geochemical studies in South Island, NZ, summarised here, provide evidence of terrane accretion processes. In a proposed tectonic model, the Early Permian Dun Mountain ophiolite was created by supra-subduction zone spreading above a W-dipping subduction zone (comparable to the present-day Izu-Bonin arc and fore arc, W Pacific). The SSZ oceanic crust in the New Zealand example is inferred to have included an intra-oceanic magmatic arc, which is no longer exposed (other than within a melange unit in Southland), but which is documented by petrographic and geochemical evidence. An additional subduction zone is likely to have dipped westwards beneath the E Gondwana margin during the Permian. As a result, relatively buoyant Early Permian supra-subduction zone oceanic crust was able to dock with the E Gondwana continental margin, terminating intra-oceanic subduction (although the exact timing is debatable). The amalgamation ('soft collision') was accompanied by crustal extension of the newly accreted oceanic slab, and

  7. Precise U-Pb Zircon Constraints on the Earliest Magmatic History of the Carolina Terrane.

    Science.gov (United States)

    Wortman; Samson; Hibbard

    2000-05-01

    The early magmatic and tectonic history of the Carolina terrane and its possible affinities with other Neoproterozoic circum-Atlantic arc terranes have been poorly understood, in large part because of a lack of reliable geochronological data. Precise U-Pb zircon dates for the Virgilina sequence, the oldest exposed part, constrain the timing of the earliest known stage of magmatism in the terrane and of the Virgilina orogeny. A flow-banded rhyolite sampled from a metavolcanic sequence near Chapel Hill, North Carolina, yielded a U-Pb zircon date of 632.9 +2.6/-1.9 Ma. A granitic unit of the Chapel Hill pluton, which intrudes the metavolcanic sequence, yielded a nearly identical U-Pb zircon date of 633 +2/-1.5 Ma, interpreted as its crystallization age. A felsic gneiss and a dacitic tuff from the Hyco Formation yielded U-Pb zircon dates of 619.9 +4.5/-3 Ma and 615.7 +3.7/-1.9 Ma, respectively. Diorite and granite of the Flat River complex have indistinguishable U-Pb upper-intercept dates of 613.9 +1.6/-1.5 Ma and 613.4 +2.8/-2 Ma. The Osmond biotite-granite gneiss, which intruded the Hyco Formation before the Virgilina orogeny, crystallized at 612.4 +5.2/-1.7 Ma. Granite of the Roxboro pluton, an intrusion that postdated the Virgilina orogeny, yielded a U-Pb upper intercept date of 546.5 +3.0/-2.4 Ma, interpreted as the time of its crystallization. These new dates both provide the first reliable estimates of the age of the Virgilina sequence and document that the earliest known stage of magmatism in the Carolina terrane had begun by 633 +2/-1.5 Ma and continued at least until 612.4 +5.2/-1.7 Ma, an interval of approximately 25 m.yr. Timing of the Virgilina orogeny is bracketed between 612.4 +5.2/-1.7 Ma and 586+/-10 Ma (reported age of the upper Uwharrie Formation). The U-Pb systematics of all units studied in the Virgilina sequence are simple and lack any evidence of an older xenocrystic zircon component, which would indicate the presence of a continental

  8. Rodinian granulites from southern Qiangtang terrane: Implications for tectonic evolution of the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Tingyuan Yuan

    2017-03-01

    Full Text Available Bordered by the Longmu Co-Shuang Hu-Lancangjiang suture zone in the north and east, as well as the Bangong Nujiang suture zone in the south and west, the southern Qiangtang terrane is one of the least-studied blocks in the Tibetan region. The early tectonic evolution of the southern Qiangtang terrane has remained a controversy for a long time. Here we report granulites from the Tongka high-grade metamorphic complexes in the southern Qiangtang terrane. The mafic granulites occur as small lenses in the felsic granulites and leucogranites with peak mineral assemblage including garnet (core + diopside + low An plagioclase + quartz. The retrograde assemblage is represented by garnet (rim + pargasite + high An plagioclase + quartz. The fine-grained aggregates of feldspar + garnet + aluminosilicates + rutile around reddish-brown biotite relics in the felsic granulites are interpreted as products of partial melting of biotites. Thermobarometric estimates for the peak assemblages of the mafic rocks are P = 17.5 kbar and T = 811 °C, whereas the retrograde assemblages of the mafic rocks experienced decompression to P = 10.4 kbar, at T = 674 °C. Zircon texture and SIMS U-Pb data reveal that the felsic granulites were derived from Achaean to Proterozoic sedimentary rocks that underwent high-temperature metamorphism and transformation to paragneisses or granitoids at 1100 to 1000 Ma. During 950–900 Ma, the crystalline rocks were further buried deeply to be transformed into the felsic granulites. We therefore interpret the Tongka high-grade metamorphic complexes to be a portion of the Rodinian continental collision belt. Evidently some domains of the Rodinian continental crust were thickened during the Grenville events, similar to the more recent processes in the Himalaya and Tibetan plateau. The Tongka high-grade metamorphic complexes which form the basement of the southern Qiangtang terrane was subsequently disrupted and

  9. Isotopic provenance analysis and terrane tectonics: a warning about sediment transport distances

    International Nuclear Information System (INIS)

    Bassett, K.N.

    1999-01-01

    Full text: In the last 10 years the field of provenance analysis has undergone a revolution with the development of single-crystal isotopic dating techniques, the most common being U/Pb zircon and 40Ar/39Ar techniques. These have allowed age determination of single crystals thus providing more detail about probable provenance of each individual grain rather than an averaged population of grains. The usefulness for resolving complex terrane accretion and translation histories was immediately obvious and there have been many studies in many different regions aimed at tracking terrane motions by provenance of individual grains upward through the stratigraphy of a basin. Recent research in the North American Cordilleran terranes and in the New Zealand Torlesse Superterrane show how widely used and powerful these provenance analysis techniques are. However, isotopic provenance analysis has often been presented as key information to resolve controversies around terrane translation histories with very little discussion of the context of sedimentary facies and sediment transport mechanisms. An example is the recent use of U/Pb detrital zircon ages as the supposedly controversy-ending evidence for the amount of lateral translation of the Insular Superterrane in British Columbia (Baja BC) (Mahoney et al., 1999). The zircon grains were separated from fine-grained turbidite deposits and could easily have been transported over very large distances by a variety of mechanisms; yet they were presented as definitively resolving the Baja BC controversy. Modern examples illustrate the problem of using the provenance of fine grained sediment to constrain terrane tectonics. Sediment in the tip of the Bengal submarine fan was transported ∼3000 km from source, first by fluvial processes then by sediment gravity flow in the submarine fan. The detrital isotopic ages of single grains are the same as the depositional ages indicating a very rapid unroofing and transport rate with minimal

  10. The Svalbard Caledonides - a collage of Laurentian, Timanian and exotic terranes assembled by Silurian - Late (?) Devonian transcurrent faulting.

    Science.gov (United States)

    Andresen, Arild; Gasser, Deta

    2014-05-01

    New field and geochronological data from NE Greenland and Svalbard indicate that most of the sub-terranes making up the Svalbard Caledonides (Eastern, Northwestern and Southwestern Terranes) are derived from Laurentias eastern margin. The Neoproterozoic deposits of the Eastern Terrane (Nordaustlandet) show an almost one to one correlation with the Late Neoproterozoic Eleonore Bay Supergroup in NE Greenland. Great similarities also exist between the substratum to the Neoproterozoic deposits in the two areas. The "Barentsian plate/continent" is interpreted to be derived from Laurentias eastern margin Lithologic similarities also exist between parts of the Northwestern Terrane and NE Greenland. The geologic evolution of Svalbard`s Southwestern Terrane, with subduction complexes and Late Neoproterozoic intrusives (Timanian ?) is poorly understood. It will, however, be argued that there is no need to invoke considerable right lateral strike-slip movement of the Motalefjellet subduction complex and related rocks from a position in Arctic Canada to their present position within the Southwestern Terrane, as proposed by some authors. The structural grain of the Svalbard Caledonides, oblique to East Greenland and Scandinavian Caledonides, as well as the Ellesmerian Orogen, is interpreted to be due to counter-clockwise rotation (c. 45o) of the Caledonian trend. A counter-clockwise rotation is to be expected when the northward moving terranes reached the E-W trending Franklinian Basin north of Greenland/Laurentia, which in Early Devonian time had not yet started to close. The model predicts that there should be a dramatic change in the Caledonian structural grain somewhere south of Bjørnøya. It is furthermore speculated that the fan-shaped orientation of Late Paleozoic rift basins in the Western Barents Sea is controlled by reactivation of the rotated structural trend (e.g. Billefjorden Fault Zone and Billefjorden Trough).

  11. Distribution and Diversity of Carboniferous and Permian Colonial Rugose Coral Faunas in Western North America: Clues for Placement of Allochthonous Terranes

    Directory of Open Access Journals (Sweden)

    Calvin H. Stevens

    2012-05-01

    Full Text Available Colonial rugose corals are common in western cratonal North America and in some of the allochthonous terranes, now amalgamated against its western margin. Throughout the Late Paleozoic, the coral faunas in these two different settings were significantly different. Comparisons of these faunas suggest that during the Mississippian the Alexander terrane probably was southwest of Arctic Alaska and the Stikine terrane probably lay west of the southern part of the North American craton. The Cache Creek terrane lay far out in the Paleopacific Ocean. The Pennsylvanian faunas suggest that the Quesnellia and Eastern Klamath terranes were situated southwest of Arctic Alaska and the Alexander terrane was somewhat farther southwest and farther from cratonal North America. The Stikine terrane continued to be positioned west of the southern part of the North American craton. During the Early Permian, terranes with a cratonal faunal aspect may have lain 2000–3000 km west of cratonal North America and latitudinally generally southwest of their present positions. In the Middle Permian these terranes were carried southward relative to the North American craton. Simultaneously the Tethyan Realm expanded eastward.

  12. Two possibilities for New Siberian Islands terrane tectonic history during the Early Paleozoic based on paleomagnetic data

    Science.gov (United States)

    Metelkin, Dmitry V.; Chernova, Anna I.; Vernikovsky, Valery A.; Matushkin, Nikolay Yu.

    2017-04-01

    The New Siberian Islands (NSI), located in the East Siberian Sea in the junction region of various structural elements, are a key target for deciphering the tectonic evolution of the Eastern Arctic. In recent years, we went on several expeditions and gathered an extensive geological material for this territory. Among other things, we could prove that the basement of the De Long and Anjou archipelagos structures is Precambrian and the overlying Paleozoic sections formed within the same terrane. The form of the boundaries of the NSI terrane are actively debated and are probably continued from the Lyakhovsky islands in the south-west to the southern parts of the submerged Mendeleev Ridge, for which there is increasing evidence of continental crust. Today there are several models that interpret the Paleozoic-Mesozoic tectonic history and structural affiliation of the NSI terrane. Some propose that the Paleozoic sedimentary section formed in a passive margin setting of the Siberian paleocontinent. Others compare its history with marginal basins of the Baltica and Laurentia continents or consider the NSI terrane as an element of the Chukotka-Alaska microplate. These models are mainly based on results of paleobiogeographical and lithological-facies analyses, including explanations of probable sources for detrital zircons. Our paleomagnetic research on sedimentary, volcanogenic-sedimentary and igneous rocks of the Anjou (Kotelny and Bel'kovsky islands) and De Long (Bennett, Jeannette and Henrietta islands) archipelagos let us calculate an apparent polar wander path for the early Paleozoic interval of geological history, which allows us to conclude that the NSI terrane could not have been a part of the continental plates listed above, but rather had active tectonic boundaries with them. Our paleomagnetic data indicate that the NSI terrane drifted slowly and steadily in the tropical and subtropical regions no higher than 40 degrees. However, the main uncertainty for the

  13. Predicted velocity and density structure of the exhuming Papua New Guinea (PNG) ultrahigh-pressure (UHP) terrane

    Science.gov (United States)

    Brownlee, S. J.; Hacker, B. R.; Salisbury, M. H.; Seward, G.; Little, T. A.; Baldwin, S.; Abers, G. A.

    2012-12-01

    The Papua New Guinea (PNG) ultrahigh-pressure (UHP) terrane is the youngest known on Earth, and is actively exhuming, making it the ideal location to study mechanisms of UHP exhumation. Electron backscatter diffraction (EBSD) measurements show that the PNG UHP terrane is dominated by rocks with weakly oriented quartz and feldspar and less abundant strongly oriented hornblende, clinopyroxene, and mica. Acoustic velocities measured at high pressures (600 MPa) show that VP is 5.8-6.3 km/s for gneiss samples, 6.5-7.7 km/s for amphibolite, and 7.7-8.2 km/s for eclogite and VS is 3.4-3.9 km/s for gneiss, 4.0-4.4 km/s for amphibolite, and 4.5-4.6 km/s for eclogite. Velocities and anisotropies calculated from mineral crystal preferred orientations (CPOs) are equivalent to within 5% of the measured values. The highest seismic anisotropy for the PNG terrane is calculated for amphibolite at 8% and 7% for VP and VS, respectively. Calculations of seismic velocities at depth based on predicted mineral assemblages indicate that the exhuming UHP terrane is of dominantly mafic composition below ~20 km depth. Anisotropy in the PNG terrane is expected to be quite low and is controlled by foliation orientation. If observable, changes in seismic anisotropy across the exhuming body may be used to differentiate among the different proposed UHP exhumation mechanisms.

  14. SHRIMP zircon U-Pb ages and tectonic implications of igneous events in the Ereendavaa metamorphic terrane in NE Mongolia

    Science.gov (United States)

    Miao, Laicheng; Zhang, Fochin; Baatar, Munkhtsengel; Zhu, Mingshuai; Anaad, Chimedtseren

    2017-08-01

    The Ereendavaa metamorphic terrane in NE Mongolia has long been considered as a Pre-Altaid block or a Precambrian cratonic terrane with a Paleoproterozoic basement overlain by Neoproterozoic-Cambrian rocks, but the idea has not been supported by any isotopic dating. Sensitive high resolution ion microprobe (SHRIMP) zircon U-Pb dating on gneisses, amphibolite and schists (mylonites) of the Ereendavaa terrane suggests that the terrane mainly formed during Early Paleozoic (495-464 Ma) and Late Paleozoic-Early Mesozoic (295-172 Ma). A minor amount of Precambrian rocks might have been involved in the formation of the protoliths of these rocks, as shown by Precambrian inherited zircons (1796-794 Ma). The new age data also suggest that the Ereendavaa terrane experienced at least two periods of magmatism: (1) Early Paleozoic (495-464 Ma) and (2) Late Paleozoic-Early Mesozoic (295-172 Ma), which are probably produced by the subduction of the Paleo Asian Ocean in the south and the subduction of the Mongol-Okhotsk Ocean in the north, respectively. The mylonitized granite (172 Ma) and undeformed pegmatite (163 Ma) are interpreted to be syn- and post-kinematic products. The new age data constrain the closure of the Mongol-Okhotsk Ocean at mid-Jurassic.

  15. New paleomagnetic data from Argun terrane. Testing its association with Amuria and the Mongol-Okhotsk Ocean

    Science.gov (United States)

    Gordienko, I. V.; Metelkin, D. V.; Vetluzhskikh, L. I.; Mikhaltsov, N. E.; Kulakov, E. V.

    2018-02-01

    In this study we present new paleomagnetic and geologic data obtained from Ediacaran and Cambrian sedimentary rocks of Argun terrane, which is traditionally considered a key-element of the hypothetical Amuria composite continent. Since 1990, when Amuria was first proposed in paleogeographic reconstructions, it became one of the key-elements in the global paleotectonic schemes. A scenario when Amuria collision with Siberian margin resulted in formation of the Mongol-Okhotsk Ocean is universally accepted and supported by majority of researchers. However, time of Amuria's final assembly and relative position of the blocks within Amuria before the collision with Siberia is still a topic of debate. Questions about principal allocation of Argun terrane and its relation to Amuria during the late Neoroterozoic — Cambrian are addressed in this study. Paleomagnetic poles for the Ediacaran — early Cambrian rocks of Argun terrane differ within an error from coeval poles from Siberia indicating that Argun terrane could have been located similar to its present day position with respect to Siberia already at 560-525 Ma. This observation calls into question association of Argun terrane with Amuria, which in classic reconstructions is usually placed close to the North China Craton. It also questions our current understanding of the Amuria paleo-continent and consequently, accuracy of global paleogeographic reconstructions for the late Neoproterozoic-Cambrian in general, and those of the eastern part of the Central Asia in particular.

  16. Seismic signatures of the Pan-African orogeny: implications for southern Indian high-grade terranes

    Science.gov (United States)

    Rai, Abhishek; Gaur, V. K.; Rai, S. S.; Priestley, K.

    2009-02-01

    We present the results of a study designed to investigate and compare the seismic characteristics of the once contiguous terranes of eastern Gondwanaland, now incorporated in five separated continental masses, which, during the Neoproterozoic (~600Ma) Pan-African orogeny, suffered a high degree of thermal stress and deformation. Receiver functions and surface wave data from stations located in East Antarctica, Sri Lanka, the southern-Indian high-grade terranes, Madagascar and the Tanzania-Mozambique belt, were used to determine the shear-wave velocity structure, Moho depth and VP/VS values of the respective crustal segments. This study provides an additional dimension to the otherwise well-documented characteristic petrology of their surface exposures and other geological signatures such as their extensive granulitization and gem formation during the Pan-African event. Analysis of the receiver functions and surface wave data for these seismic stations located on their present day widely distributed continental fragments have been made. It is observed that with the exception of KOD (at Kodaikanal hill), situated on the southern Indian granulites having the thickest crust (~43.5 km), most of the Pan-African granulitic terranes have a crustal thicknesses of ~37 +/- 0.8km, with a transition to higher velocity at mid-crustal depths, and that their bulk composition is felsic. Average crustal VP/VS values (1.704 +/- 0.03) and thicknesses (37.8 +/- 0.8km), for four stations (SYO, PALK, TRV and ABPO), now located in East Antarctica, Sri Lanka, India and Madagascar, respectively, show remarkable similarity, indicating that the Pan-African orogeny was extensive enough to reorder the crustal structure of a wide region with a broadly similar stamp.

  17. A kinematic model for the formation of the Siletz-Crescent forearc terrane by capture of coherent fragments of the Farallon and Resurrection plates

    Science.gov (United States)

    McCrory, Patricia A.; Wilson, Douglas S.

    2013-01-01

    The volcanic basement of the Oregon and Washington Coast ranges has been proposed to represent a pair of tracks of the Yellowstone hotspot formed at a mid-ocean ridge during the early Cenozoic. This interpretation has been questioned on many grounds, especially that the range of ages does not match the offshore spreading rates and that the presence of continental coarse clastic sediments is difficult to reconcile with fast convergence rates between the oceanic plates and North America. Updates to basement geochronology and plate motion history reveal that these objections are much less serious than when they were first raised. Forward plate kinematic modeling reveals that predicted basement ages can be consistent with the observed range of about 55–49 Ma, and that the entire basement terrane can form within about 300 km of continental sources for clastic sediments. This kinematic model indicates that there is no firm reason to reject the near-ridge hotspot hypothesis on the basis of plate motions. A novel element of the model is the Resurrection plate, previously proposed to exist between the Farallon and Kula plates. By including the defunct Resurrection plate in our reconstruction, we are able to model the Farallon hotspot track as docking against the Oregon subduction margin starting about 53 Ma, followed by docking of the Resurrection track to the north starting about 48 Ma. Accretion of the Farallon plate fragment and partial subduction of the Resurrection fragment complicates the three-dimensional structure of the modern Cascadia forearc. We interpret the so-called “E” layer beneath Vancouver Island to be part of the Resurrection fragment. Our new kinematic model of mobile terranes within the Paleogene North American plate boundary allows reinterpretation of the three-dimensional structure of the Cascadia forearc and its relationship to ongoing seismotectonic processes.

  18. High-precision UPb ages of metamorphic rutile: application to the cooling history of high-grade terranes

    Science.gov (United States)

    Mezger, K.; Hanson, G.N.; Bohlen, S.R.

    1989-01-01

    Metamorphic rutiles occurring in granulite and upper amphibolite facies metapelitic rocks of the Archean Pikwitonei granulite domain (Manitoba) and the Proterozoic Adirondack terrane (New York) give concordant and near concordant UPb ages. The Pb concentrations in rutile range from 2.85 to 168 ppm, U concentrations range from 10.9 to 390 ppm and the measured 206Pb 204Pb ratios range from 182 to 22,100 corresponding to 238U 204Pb ratios of 398-75,100. The proportions of radiogenic 208Pb are very low, ranging from 0.0 to 6.9% of total radiogenic Pb. The habits of the rutile crystals range from stubby to acicular, the physical properties vary from opaque/black to transparent/reddish-brown. Separate batches of black and reddish-brown rutile grains from the same samples have similar U and Pb concentrations, Pb-isotope ratios, and yield the same U Pb ages within analytical uncertainty. No correlation of U concentration and 206Pb 204Pb ratios with morphology or color of the rutiles was observed among the samples analyzed. Most rutiles yield concordant UPb ages which are reproducible within analytical uncertainty, i.e. generally ??2 Ma. The UPb ages for prograde rutile are younger than the time of peak metamorphism given by UPb ages for garnet and zircon, and also younger than UPb ages for sphene and monazite, and 40Ar 39Ar and KAr ages for hornblende but older than 40Ar 39Ar and KAr ages for biotite from the same area. This suggests that the rutile ages reflect cooling below closure temperatures. Within a single hand-specimen, and thus for an identical thermal history, larger rutile grains give older ages than do smaller grains. This suggests that volume diffusion is the most probable mechanism responsible for the ages being younger than the time of peak metamorphism. It also suggests that the dimensions for such diffusion are directly related to the dimensions of the rutile crystal and not to the dimensions of sub-grain domains, as is the case for Ar diffusion in

  19. Interpretation of gravity profiles across the northern Oaxaca terrane, its boundaries and the Tehuacán Valley, southern Mexico

    Science.gov (United States)

    Campos-Enríquez, J. O.; Alatorre-Zamora, M. A.; Keppie, J. D.; Belmonte-Jiménez, S. I.; Ramón-Márquez, V. M.

    2014-12-01

    A gravity study was conducted across the northern Oaxaca terrane and its bounding faults: the Caltepec and Oaxaca Faults to the west and east, respectively. These faults juxtapose the Oaxaca terrane against the Mixteca and Juarez terranes, respectively. The Oaxaca Fault also forms the eastern boundary of the Cenozoic Tehuacán depression. On the west, at depth, the Tehuacán valley is limited by the normal buried Tehuacán Fault. This gravity study reveals that the Oaxaca Fault system gives rise to a series of east tilted basamental blocks (Oaxaca Complex). The tectonic depression is filled with Phanerozoic rocks and has a deeper depocenter to the west. The gravity data also indicate that on the west, the Oaxaca Complex, the Caltepec and Santa Lucia faults continue northwestwards beneath Phanerozoic rocks. A major E-W to NE-SW discontinuity is inferred to exist between profiles 1 and 2.

  20. Two-stage terrane assembly in Western Gondwana: Insights from structural geology and geophysical data of central Borborema Province, NE Brazil

    Science.gov (United States)

    Santos, Lauro Cézar M. de Lira; Dantas, Elton L.; Vidotti, Roberta M.; Cawood, Peter A.; dos Santos, Edilton J.; Fuck, Reinhadt A.; Lima, Haroldo M.

    2017-10-01

    Combined geophysical and structural data from the Transversal Subprovince of the Borborema Province (NE Brazil) highlight the internal structure of, and interrelationships between, the constituent terranes. Radiometric and magnetic maps show distinctive signatures for the Archean-Paleoproterozoic Alto Moxotó and Meso-to Neoproterozoic Alto Pajeú and Pernambuco-Alagoas terranes. Mapped radiometric and first and second order magnetic lineaments, associated with Euler deconvolution, enable correlation between geophysical data and major structures. In addition to early related deformation of the Alto Moxotó Terrane, combined analysis of late transposition foliations, lineations and kinematic criteria reveal a complex structural evolution marked by two distinct assembly stages. The first phase is characterized by thrust tectonics with top-to-the-south vergence, resulting in the juxtaposition of the allochtonous Alto Pajeú Terrane with the structurally underlying Alto Moxotó Terrane. The terrane boundary is delineated by the Serra de Jabitacá Shear Zone, which is associated with low dipping collisional granitic sheets and ca. 1.0 Ga mafic-ultramafic rocks interpreted as obtudcted ophiolite remnants. Later strike-slip movements strongly folded and obliterated thrust-related markers, and the continental scale E-W Pernambuco Lineament is interpreted as the result of lateral assembly between the composite Alto Pajeú-Alto Moxotó terranes and the Pernambuco-Alagoas Terrane during the metamorphic peak of the Brasiliano orogeny. Evolution of the Borborema Province reflects accretionary processes during the assembly of Western Gondwana.

  1. The Punta del Este Suspect Terrane: a possible counterpart in Eastern Uruguay of the Namaqua Complex and Gariep Belt in Western Africa

    International Nuclear Information System (INIS)

    Preciozzi, F.; Basei, M.; Peel, E.

    2005-01-01

    two tectono-stratigraphic sets with the eastern portion occupied by parautochthonous units of a passive continental margin (Port Nolloth Zone) and a western allochthonous domain (Marmora Terrane). The evidences of blueschist facies metamorphism, countless times referred in the literature (Kröner, 1974; Porada, 1979), have been recently ruled out by Frimmel and Hartnady (1992). The sedimentation period of the Gariep Group is attributed to the Neoproterozoic because it lays discordantly on the rhyolite units (Ross Pinah Formation) dated by the single zircon evaporation technique as 735Ma (Frimmel, 1995). Meert §& Van der Voo (1994) correlated diamictite intercalations, probably of age between 580 and 560 Ma, in the upper portion of the Gariep Group with the glacial deposits of Vendian age. The northeastern portion of the Gariep Group is covered by not metamorphosed sediments of the Nama Group. In the South-American counterpart, that is, the South-Brazilian region and the Uruguayan territory, an old western domain is observed The Central Domain is represented by the Rio de La Plata Craton (sensus Almeida et al.,1973) ,by de Nico Perez Terrane (Bossi et al.,1992 ;Valentines Block,PavasTerrane (Preciozzi et al.,1979) and the Rivera granitic-gneissic complex ..All of them were generated or intensively reworked during the Neoproterozoic, distributed along its eastern border and as a whole organised in the NE-SW direction. In these domain, a granitic-migmatitic infrastructure and sedimentary basins and low- to medium metamorphic grade covers predominate, related to the Lavalleja-supergroup and Zanja del Cerro Grande Group The Rocha formation is developed as a metasedimentary cover in the Punta del Este Terrane,being associated to the Atlantic Domain. Geochronologic studies recently performed in the southeastern portion of Uruguay allowed the identification of igneous rocks with U-Pb ages in zircons ranging from 650 to 1000Ma. These ages, added to the geological

  2. Cretaceous–Eocene provenance connections between the Palawan Continental Terrane and the northern South China Sea margin

    NARCIS (Netherlands)

    Shao, Lei; Cao, Licheng; Qiao, Peijun; Zhang, Xiangtao; Li, Qianyu; van Hinsbergen, Douwe J.J.

    2017-01-01

    The plate kinematic history of the South China Sea opening is key to reconstructing how the Mesozoic configuration of Panthalassa and Tethyan subduction systems evolved into today's complex Southeast Asian tectonic collage. The South China Sea is currently flanked by the Palawan Continental Terrane

  3. Microprobe monazite constraints for and early (ca. 790 Ma) Braziliano orogeny: The Embu Terrane, southeastern Brazil

    International Nuclear Information System (INIS)

    Vlach, Silvio R.F

    2001-01-01

    The evolution of the Mantiqueira Orogenetic System, Southeastern Brazil, comprises discrete episodes of tectonic collage and docking of remnants of Rodinia break-up in the borders of the Sao Francisco Craton. This system is related to the closure of the Adamastor ocean and assemblage of the western Gondwana super-continent during Neoproterozoic times (ca. 610-530 Ma, Brito Neves et al., 1999; Campos Neto, 2000). This report presents monazite microprobe dating results for metassediments from the Embu Complex, an important lithological unit from the Ribeira Belt, currently included in the Juiz de Fora terrane, a unit added to the Sao Francisco Craton at ca. 600-580 Ma. (Campos Neto, 2000). The age results unravel a main metamorphic episode and related orogeny at ca. 790 Ma and bring new insights concerning the agglutination of Gondwana in this region during the Neoproterozoic (au)

  4. The metallogeny of Late Triassic rifting of the Alexander terrane in southeastern Alaska and northwestern British Columbia

    Science.gov (United States)

    Taylor, C.D.; Premo, W.R.; Meier, A.L.; Taggart, J.E.

    2008-01-01

    A belt of unusual volcanogenic massive sulfide (VMS) occurrences is located along the eastern margin of the Alexander terrane throughout southeastern Alaska and northwestern British Columbia and exhibits a range of characteristics consistent with a variety of syngenetic to epigenetic deposit types. Deposits within this belt include Greens Creek and Windy Craggy, the economically most significant VMS deposit in Alaska and the largest in North America, respectively. The occurrences are hosted by a discontinuously exposed, 800-km-long belt of rocks that consist of a 200- to 800-m-thick sequence of conglomerate, limestone, marine elastic sedimentary rocks, and tuff intercalated with and overlain by a distinctive unit of mafic pyroclastic rocks and pillowed flows. Faunal data bracket the age of the host rocks between Anisian (Middle Triassic) and late Norian (late Late Triassic). This metallogenic belt is herein referred to as the Alexander Triassic metallogenic belt. The VMS occurrences show systematic differences in degree of structural control, chemistry, and stratigraphic setting along the Alexander Triassic metallogenic belt that suggest important spatial or temporal changes in the tectonic environment of formation. At the southern end of the belt, felsic volcanic rocks overlain by shallow-water limestones characterize the lower part of the sequence. In the southern and middle portion of the belt, a distinctive pebble conglomerate marks the base of the section and is indicative of high-energy deposition in a near slope or basin margin setting. At the northern end of the belt the conglomerates, limestones, and felsic volcanic rocks are absent and the belt is composed of deep-water sedimentary and mafic volcanic rocks. This northward change in depositional environment and lithofacies is accompanied by a northward transition from epithermal-like structurally controlled, discontinuous, vein- and pod-shaped, Pb-Zn-Ag-Ba-(Cu) occurrences with relatively simple mineralogy

  5. Are turtleback fault surfaces common structural elements of highly extended terranes?

    Science.gov (United States)

    Çemen, Ibrahim; Tekeli, Okan; Seyitoğlu, Gűrol; Isik, Veysel

    2005-12-01

    The Death Valley region of the U.S.A. contains three topographic surfaces resembling the carapace of a turtle. These three surfaces are well exposed along the Black Mountain front and are named the Badwater, Copper Canyon, and Mormon Point Turtlebacks. It is widely accepted that the turtlebacks are also detachment surfaces that separate brittlely deformed Cenozoic volcanic and sedimentary rocks of the hanging wall from the strongly mylonitic, ductilely deformed pre-Cenozoic rocks of the footwall. We have found a turtleback-like detachment surface along the southern margin of the Alasehir (Gediz) Graben in western Anatolia, Turkey. This surface qualifies as a turtleback fault surface because it (a) is overall convex-upward and (b) separates brittlely deformed hanging wall Cenozoic sedimentary rocks from the ductilely to brittlely deformed, strongly mylonitic pre-Cenozoic footwall rocks. The surface, named here Horzum Turtleback, contains striations that overprint mylonitic stretching lineations indicating top to the NE sense of shear. This suggests that the northeasterly directed Cenozoic extension in the region resulted in a ductile deformation at depth and as the crust isostatically adjusted to the removal of the rocks in the hanging wall of the detachment fault, the ductilely deformed mylonitic rocks of the footwall were brought to shallower depths where they were brittlely deformed. The turtleback surfaces have been considered unique to the Death Valley region, although detachment surfaces, rollover folds, and other extensional structures have been well observed in other extended terranes of the world. The presence of a turtleback fault surface in western Anatolia, Turkey, suggests that the turtleback faults may be common structural features of highly extended terranes.

  6. A comparison of the seismic structure of oceanic island arc crust and continental accreted arc terranes

    Science.gov (United States)

    Calvert, A. J.

    2015-12-01

    Amalgamation of island arcs and their accretion to pre-existing continents is considered to have been one of the primary mechanisms of continental growth over the last 3 Ga, with arc terranes identified within Late Archean, Proterozoic, and Phanerozoic continental crust. Crustal-scale seismic refraction surveys can provide P wave velocity models that can be used as a proxy for crustal composition, and although they indicate some velocity variation in accreted arcs, these terranes have significantly lower velocities, and are hence significantly more felsic, than modern island arcs. Modern oceanic arcs exhibit significant variations in crustal thickness, from as little as 10 km in the Bonin arc to 35 km in the Aleutian and northern Izu arcs. Although globally island arcs appear to have a mafic composition, intermediate composition crust is inferred in central America and parts of the Izu arc. The absence of a sharp velocity contrast at the Moho appears to be a first order characteristic of island arc crust, and indicates the existence of a broad crust-mantle transition zone. Multichannel seismic reflection surveys complement refraction surveys by revealing structures associated with variations in density and seismic velocity at the scale of a few hundred meters or less to depths of 60 km or more. Surveys from the Mariana and Aleutian arcs show that modern middle and lower arc crust is mostly non-reflective, but reflections are observed from depths 5-25 km below the refraction Moho suggesting the localized presence of arc roots that may comprise gabbro, garnet gabbro, and pyroxenite within a broad transition from mafic lower crust to ultramafic mantle. Such reflective, high velocity roots are likely separated from the overlying arc crust prior to, or during arc-continent collision, and seismic reflections within accreted arc crust document the collisional process and final crustal architecture.

  7. Geophysical modeling of the northern Appalachian Brompton-Cameron, Central Maine, and Avalon terranes under the New Jersey Coastal Plain

    Science.gov (United States)

    Maguire, T.J.; Sheridan, R.E.; Volkert, R.A.

    2004-01-01

    A regional terrane map of the New Jersey Coastal Plain basement was constructed using seismic, drilling, gravity and magnetic data. The Brompton-Cameron and Central Maine terranes were coalesced as one volcanic island arc terrane before obducting onto Laurentian, Grenville age, continental crust in the Taconian orogeny [Rankin, D.W., 1994. Continental margin of the eastern United States: past and present. In: Speed, R.C., (Ed.), Phanerozoic Evolution of North American Continent-Ocean Transitions. DNAG Continent-Ocean Transect Volume. Geological Society of America, Boulder, Colorado, pp. 129-218]. Volcanic island-arc rocks of the Avalon terrane are in contact with Central Maine terrane rocks in southern Connecticut where the latter are overthrust onto the Brompton-Cameron terrane, which is thrust over Laurentian basement. Similarities of these allochthonous island arc terranes (Brompton-Cameron, Central Maine, Avalon) in lithology, fauna and age suggest that they are faulted segments of the margin of one major late Precambrian to early Paleozoic, high latitude peri-Gondwana island arc designated as "Avalonia", which collided with Laurentia in the early to middle Paleozoic. The Brompton Cameron, Central Maine, and Avalon terranes are projected as the basement under the eastern New Jersey Coastal Plain based on drill core samples of metamorphic rocks of active margin/magmatic arc origin. A seismic reflection profile across the New York Bight traces the gentle dipping (approximately 20 degrees) Cameron's Line Taconian suture southeast beneath allochthonous Avalon and other terranes to a 4 sec TWTT depth (approximately 9 km) where the Avalonian rocks are over Laurentian crust. Gentle up-plunge (approximately 5 degrees) projections to the southwest bring the Laurentian Grenville age basement and the drift-stage early Paleozoic cover rocks to windows in Burlington Co. at approximately 1 km depth and Cape May Co. at approximately 2 km depths. The antiformal Shellburne

  8. The effect of the mineral dissolution and deformation of slope stability on nature terrane

    Science.gov (United States)

    Choi, J.; Chae, B.

    2012-12-01

    A landslide on nature terrane is mainly occurred by rainfall, snowmelt, earthquakes and rock/soil weathering process. Especially, the role of rainfall and rock/soil weathering in slope stability is very important because it causes decreased in shear strength by reducing the soil cohesion. Quartz is the most abundant crust-forming mineral on earth. This mineral contributes to the formation of crystalline rocks such as granite, gneiss, and sandstone. Therefore, in case of the slope consisted by granite, gneiss, and sandstone, the slope stability can be affected by the mineral weathering process such as mineral dissolution and deformation because the shear strength, one of the key factors to calculate the slope stability, can be reduced by mineral weathering. That is, mineral weathering including dissolution and deformation between the minerals can reduce the soil cohesion on nature terrane. Many studies have found that quartz exhibits a notably slow rate of dissolution at room temperature. Therefore, to achieve rapid dissolution at room temperature, other methods should be considered, including 1) expanding the surface area of quartz to increase the reaction area and 2) applying high pressure to the contact area of crystals to increase the dissolution rate. However, dissolution of the surface of quartz is difficult to observe when using powdered quartz to maximize the surface area. Therefore, we used beads and single quartz crystals to observe and analyze the dissolution of the surface. The former can be used to maximize the surface area of quartz, and high-pressure conditions can be applied to the latter. A confocal laser scanning microscope (CLSM) was subsequently used to observe the dissolution patterns on the quartz surface. Numerical analyses using the finite element method (FEM) were also performed to quantify the deformation of the contact area. Quartz dissolution was observed in both experiments. This deformation was due to a concentrated compressive stress

  9. Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting

    Science.gov (United States)

    Chen, Chen; Gilbert, Hersh; Fischer, Karen M.; Andronicos, Christopher L.; Pavlis, Gary L.; Hamburger, Michael W.; Marshak, Stephen; Larson, Timothy; Yang, Xiaotao

    2018-01-01

    Seismic discontinuities between the Moho and the inferred lithosphere-asthenosphere boundary (LAB) are known as mid-lithospheric discontinuities (MLDs) and have been ascribed to a variety of phenomena that are critical to understanding lithospheric growth and evolution. In this study, we used S-to-P converted waves recorded by the USArray Transportable Array and the OIINK (Ozarks-Illinois-Indiana-Kentucky) Flexible Array to investigate lithospheric structure beneath the central U.S. This region, a portion of North America's cratonic platform, provides an opportunity to explore how terrane accretion, cratonization, and subsequent rifting may have influenced lithospheric structure. The 3D common conversion point (CCP) volume produced by stacking back-projected Sp receiver functions reveals a general absence of negative converted phases at the depths of the LAB across much of the central U.S. This observation suggests a gradual velocity decrease between the lithosphere and asthenosphere. Within the lithosphere, the CCP stacks display negative arrivals at depths between 65 km and 125 km. We interpret these as MLDs resulting from the top of a layer of crystallized melts (sill-like igneous intrusions) or otherwise chemically modified lithosphere that is enriched in water and/or hydrous minerals. Chemical modification in this manner would cause a weak layer in the lithosphere that marks the MLDs. The depth and amplitude of negative MLD phases vary significantly both within and between the physiographic provinces of the midcontinent. Double, or overlapping, MLDs can be seen along Precambrian terrane boundaries and appear to result from stacked or imbricated lithospheric blocks. A prominent negative Sp phase can be clearly identified at 80 km depth within the Reelfoot Rift. This arrival aligns with the top of a zone of low shear-wave velocities, which suggests that it marks an unusually shallow seismic LAB for the midcontinent. This boundary would correspond to the top of a

  10. Temperature time evolution of the Assynt Terrane of the Lewisian Gneiss Complex of Northwest Scotland from zircon U-Pb dating and Ti thermometry

    OpenAIRE

    CROWLEY, QUENTIN

    2015-01-01

    The Lewisian Gneiss Complex of Northwest Scotland is a classic Precambrian basement gneiss complex. The Lewisian is divided into a number of terranes on the basis of structural, metamorphic and geochronological evidence. The most well-studied of these is the Assynt Terrane, which forms the central part of the Lewisian outcrop on the Scottish mainland. Field evidence shows that it has a complex tectonothermal history, the early stages of which remain poorly constrained. This paper sets out to ...

  11. Bokan Mountain peralkaline granitic complex, Alexander terrane (southeastern Alaska): evidence for Early Jurassic rifting prior to accretion with North America

    Science.gov (United States)

    Dostal, Jaroslav; Karl, Susan M.; Keppie, J. Duncan; Kontak, Daniel J.; Shellnutt, J. Gregory

    2013-01-01

    The circular Bokan Mountain complex (BMC) on southern Prince of Wales Island, southernmost Alaska, is a Jurassic peralkaline granitic intrusion about 3 km in diameter that crosscuts igneous and metasedimentary rocks of the Alexander terrane. The BMC hosts significant rare metal (rare earth elements, Y, U, Th, Zr, and Nb) mineralization related to the last stage of BMC emplacement. U–Pb (zircon) and 40Ar/39Ar (amphibole and whole-rock) geochronology indicates the following sequence of intrusive activity: (i) a Paleozoic basement composed mainly of 469 ± 4 Ma granitic rocks; (ii) intrusion of the BMC at 177 ± 1 Ma followed by rapid cooling through ca. 550 °C at 176 ± 1 Ma that was synchronous with mineralization associated with vertical, WNW-trending pegmatites, felsic dikes, and aegirine–fluorite veins and late-stage, sinistral shear deformation; and (iii) intrusion of crosscutting lamprophyre dikes at >150 Ma and again at ca. 105 Ma. The peralkaline nature of the BMC and the WNW trend of associated dikes suggest intrusion during NE–SW rifting that was followed by NE–SW shortening during the waning stages of BMC emplacement. The 177 Ma BMC was synchronous with other magmatic centres in the Alexander terrane, such as (1) the Dora Bay peralkaline stock and (2) the bimodal Moffatt volcanic suite located ∼30 km north and ∼100 km SE of the BMC, respectively. This regional magmatism is interpreted to represent a regional extensional event that precedes deposition of the Late Jurassic – Cretaceous Gravina sequence that oversteps the Wrangellia and Alexander exotic accreted terranes and the Taku and Yukon–Tanana pericratonic terranes of the Canadian–Alaskan Cordillera.

  12. North America as an exotic terrane'' and the origin of the Appalachian--Andean Mountain system

    Energy Technology Data Exchange (ETDEWEB)

    Dalziel, I.W.D; Gahagan, L.M. (Univ. of Texas, Austin, TX (United States). Inst. for Geophysics); Dalla Salda, L.H. (Univ. Nacional de La Plata, La Plata (Argentina). Centro de Investigaciones Geologicas)

    1992-01-01

    North America was sutured to Gondwana in the terminal Alleghanian event of Appalachian orogenesis, thus completing the late Paleozoic assembly of Pangea. The suggestion that the Pacific margins of East Antarctica-Australia and Laurentia may have been juxtaposed during the Neoproterozoic prompts reevaluation of the widely held assumptions that the ancestral Appalachian margin rifted from northwestern Africa during the earliest Paleozoic opening of Iapetus, and remained juxtaposed to that margin, even though widely separated from it at times, until the assembly of Pangea. The lower Paleozoic carbonate platform of northwestern Argentina has been known for a long time to contain Olenellid trilobites of the Pacific or Columbian realm. Although normally regarded as some kind of far-travelled terrane that originated along the Appalachian margin of Laurentia, it has recently been interpreted as a fragment detached from the Ouachita embayment of Laurentia following Taconic-Famatinian collision with Gondwana during the Ordovician. The Oaxaca terrane of Mexico, on the other hand, contains a Tremadocian trilobite fauna of Argentine-Bolivian affinities, and appears to have been detached from Gondwana following the same collision. The Wilson cycle'' of Iapetus ocean basin opening and closing along the Appalachian and Andean orogens may have involved more than one such continental collision during clockwise drift of Laurentia around South America following late Neoproterozoic to earliest Cambrian separation. Together with the collisions of baltic and smaller terranes with Laurentia, this could explain the protracted Paleozoic orogenic history of both the Appalachian and proto-Andean orogens.

  13. UTE park group and other meso proterozoic units of the Nico Perez terrane: Rodina connecting

    International Nuclear Information System (INIS)

    Gaucher, C; Chemale, F.; Bossi, J.; Sial, A.; Chiglino, L.

    2010-01-01

    The Parque UTE Group is a volcano sedimentary succession metamorphosed in green schist facies, comprising (from base to top): the Canada Espinillo Formation (prasinites, pelites, andesite s), the Mina Valencia Formation (dolostones, limestones, marls) and the Cerro del Mast il Formation (black pelites, limestones, acid tuffs). Thickness of the GPU exceeds 2.5 km; base and top are not exposed. U-Pb zircon ages for basic magmatic rocks at the base and rhyolites at the top yielded 1492±4 and 1429±21 Ma, respectively. 13C values of carbonates of the Pug are characterized by a plateau at +1‰ VPDB, bracketed between two negative excursions.These values are consistent with an early Mesoproterozoic depositional age. Detrital zircon age spectra show that the source area of the GPU was the Nico Perez Terrane, being thus native to the Rio de la Plata Craton (Rpc). A Mesoproterozoic tectonic event at 1.25 Ga, recorded at both sides of the Sarandi del Yi mega shear, is discussed. New U-Pb zircon ages are presented for the La China Complex at its type area, where a schistosity N60W cuts the metamorphic banding and is parallel to thrusts dated K-Ar at 1253±32 Ma. The ages obtained are: 3096±45 Ma (main metamorphic event) and 1252 Ma (lower intercept). These data confirm the occurrence of a Grenvillian-aged tectonic event in Uruguay, suggesting that the RPC was part of the super continent Rodinia

  14. Paragneiss zircon geochronology and trace element geochemistry, North Qaidam HP/UHP terrane, western China

    Science.gov (United States)

    Mattinson, C.G.; Wooden, J.L.; Zhang, J.X.; Bird, D.K.

    2009-01-01

    In the southeastern part of the North Qaidam terrane, near Dulan, paragneiss hosts minor peridotite and UHP eclogite. Zircon geochronology and trace element geochemistry of three paragneiss samples (located within a ???3 km transect) indicates that eclogite-facies metamorphism resulted in variable degrees of zircon growth and recrystallization in the three samples. Inherited zircon core age groups at 1.8 and 2.5 Ga suggest that the protoliths of these rocks may have received sediments from the Yangtze or North China cratons. Mineral inclusions, depletion in HREE, and absence of negative Eu anomalies indicate that zircon U-Pb ages of 431 ?? 5 Ma and 426 ?? 4 Ma reflect eclogite-facies zircon growth in two of the samples. Ti-in-zircon thermometry results are tightly grouped at ???660 and ???600 ??C, respectively. Inclusions of metamorphic minerals, scarcity of inherited cores, and lack of isotopic or trace element inheritance demonstrate that significant new metamorphic zircon growth must have occurred. In contrast, zircon in the third sample is dominated by inherited grains, and rims show isotopic and trace element inheritance, suggesting solid-state recrystallization of detrital zircon with only minor new growth. ?? 2009 Elsevier Ltd.

  15. Post-peak metamorphic evolution of the Sumdo eclogite from the Lhasa terrane of southeast Tibet

    Science.gov (United States)

    Cao, Dadi; Cheng, Hao; Zhang, Lingmin; Wang, Ke

    2017-08-01

    A reconstruction of the pressure-temperature-time (P-T-t) path of high-pressure eclogite-facies rocks in subduction zones may reveal important information about the tectono-metamorphic processes that occur at great depths along the plate interface. The majority of studies have focused on prograde to peak metamorphism of these rocks, whereas after-peak metamorphism has received less attention. Herein, we present a detailed petrological, pseudosection modeling and radiometric dating study of a retrograded eclogite sample from the Sumdo ultrahigh pressure belt of the Lhasa terrane, Tibet. Mineral chemical variations, textural discontinuities and thermodynamic modeling suggest that the eclogite underwent an exhumation-heating period. Petrographic observations and phase equilibria modeling suggest that the garnet cores formed at the pressure peak (∼2.5 GPa and ∼520 °C) within the lawsonite eclogite-facies and garnet rims (∼1.5 GPa and spans an interval of ∼7 million years, which is a minimum estimate of the duration of the eclogite-facies metamorphism of the Sumdo eclogite.

  16. Petrography and geochronology (U/Pb-Sm/Nd) the Passagem Granite, Pensamiento Granitoid Complex, Paragua Terrane, SW Amazon Craton, Mato Grosso, Brazil; Petrologia e geocronologia (U/Pb-Sm/Nd) do Granito Passagem, Complexo Granitoide Pensamiento, SW do Craton Amazonico (MT)

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Gisely Carmo de, E-mail: giselycarmo@hotmail.co [Universidade Federal de Mato Grosso (ICET/UFMT), Cuiaba, MT (Brazil). Inst. de Ciencias Exatas e da Terra. Programa de Pos-Graduacao em Geociencias; Sousa, Maria Zelia Aguiar de, E-mail: mzaguiar@terra.com.b [Universidade Federal de Mato Grosso(ICET/UFMT), Cuiaba, MT (Brazil). Inst. de Ciencias Exatas e da Terra. Dept. de Recursos Minerais; Ruiz, Amarildo Salina; Matos, Joao Batista de, E-mail: asruiz@gmail.co, E-mail: jmatos@cpd.ufmt.b [Universidade Federal de Mato Grosso (ICET/UFMT), Cuiaba, MT (Brazil). Inst. de Ciencias Exatas e da Terra. Dept. de Geologia Geral

    2010-09-15

    The Passagem granite includes stocks, plugs and dikes located in the Ricardo Franco hill - Vila Bela da Santissima Trindade region - state of Mato Grosso, central Brazil. The Passagem Granite is included in the Paragua terrane - SW Amazonian Craton. It consists of isotropic monzogranite, sienogranite and more rarely granodiorites with leucocratic dark gray to white color. These rocks range from hypidomorphic inequigranular to xenomorphic texture, fine to medium grained. Biotite is the only primary mafic present as essential phase and characterize an expanded slightly acid sequence formed by a sub-alkaline magmatism of high-potassium calc-alkaline, slightly peraluminous composition from arc magmatic tectonic environment during a post-collisional period. Mechanism of fractional crystallization of plagioclase, biotite, titanite, apatite and zircon associated with simultaneous crustal assimilation are suggested for the evolution of these rocks. The results support the hypothesis of a post-collisional magmatism in the Paragua terrane at 1284 +- 20 Ma corresponding to the crystallization age of the Passagem granite. This paper propose that Passagem Granite represents as an extension in Brazilian terrane of the Pensamiento Granitoid Complex. (author)

  17. Combined U-Pb SHRIMP and Hf isotope study of the Late Paleozoic Yaminué Complex, Rio Negro Province, Argentina: Implications for the origin and evolution of the Patagonia composite terrane

    Directory of Open Access Journals (Sweden)

    Carlos J. Chernicoff

    2013-01-01

    Combining geological and isotope data, as well as geophysical models, we identify the Yaminué Complex within the La Esperanza-Yaminué crustal block flanked by two other, distinct crustal blocks: the Eastern block which forms part of the Patagonia terrane sensu stricto, located in the eastern Patagonian region, and the Western block forming part of the Southern Patagonia terrane. Their origins and timing of amalgamation to form the Patagonia composite terrane are also discussed.

  18. Recognition of the Kaweka Terrane in northern South Island, New Zealand : preliminary evidence from Rb-Sr metamorphic and U-Pb detrital zircon ages

    International Nuclear Information System (INIS)

    Adams, C.J.; Mortimer, N.; Campbell, H.J.; Griffin, W.L.

    2011-01-01

    Detrital zircon U-Pb ages and Rb-Sr metamorphic ages from low-grade Torlesse Supergroup metasedimentary rocks from North Canterbury and Marlborough provide preliminary evidence for a continuation of the Kaweka Terrane of the central North Island into the Torlesse Composite Terrane of the South Island. This would extend from the south side of the Wairau Fault in the upper Wairau River valley southwards to the Lake Tennyson and Lake Sumner areas, and as far as Hawarden. Rb-Sr ages indicate Jurassic metamorphism, 170±24 Ma, with initial 87 Sr/ 86 Sr ratios at that time 0.7073 ± 0.0007 i.e. similar to their North Island counterparts. These Kaweka Terrane rocks have detrital zircon ages that follow the distinctive pattern of the Torlesse rocks in general, i.e. substantial (>30%) Permian-Triassic and Precambrian-Early Palaeozoic groupings, but they also have minor youngest age components c. 175-165 Ma which constrain a maximum Early-Middle Jurassic depositional age. In detail, significant, older zircon components are Late Permian-Early Triassic (260-240 Ma) and Late Triassic (220-210 Ma), but the Precambrian-Early Palaeozoic detrital zircon ages are more scattered. The Kaweka Terrane thus forms a linear belt (c. 500 km) along the length of the Torlesse Composite Terrane in both North and South Islands. In the South Island it coincides with the Esk Head Belt, i.e. east of the Rakaia Terrane (Triassic-Late Permian) and west of the Pahau Terrane (Early Cretaceous-Late Jurassic). (author). 61 refs., 4 figs., 2 tabs.

  19. Park Volcanics, Murihiku Terrane, New Zealand : petrology, petrochemistry, and tectonic significance

    International Nuclear Information System (INIS)

    Coombs, D.S.; Cook, N.D.J.; Kawachi, Y.; Johnstone, R.D.; Gibson, I.L.

    1996-01-01

    The Late Triassic to Early Jurassic Park Volcanics Group comprises minor shallow intrusive and extrusive bodies emplaced during mainly marine sedimentation of the Murihiku Terrane, southern New Zealand. Gowan Andesite in western Southland and Glenham Porphyry andesites in eastern Southland are high-K andesites. Glassy examples have commonly lost K during alteration. Orthoclase contents of Or 3.6-3.7 in plagioclase phenocrysts at An 50 confirm the high-K nature of the melts at the time of phenocryst crystallisation. The Gowan andesites have higher Fe/Mg than the Glenham and related differences in minor element chemistry suggesting lower ∫O 2 during fractionation of the parent magma. Pinney Volcanics in western Southland are mostly high-K trachydacites but, like Glenham Porphyry, include minor rhyolite. Barnicoat Andesite in the Nelson area is medium-K olivine andesite, marginally tholeiitic in terms of its FeO*/MgO versus SiO 2 behaviour, but otherwise is typically calc-alkaline, as are the Gowan, Glenham, and Pinney. Analyses of pyroxenes (augites, orthopyroxenes, reaction rim and groundmass pigeonites) reveal xenocrysts recording an early stage of magma fractionation, slight iron enrichment in the andesite stage, and lowered Fe/Mg and increased Ca contents in augites of the most felsic rocks. Titanian tschermakite and titanian magnesio-tschermakite of deep-seated origin participated in fractionation leading to the Pinney Volcanics, and magnesio-hornblende, edenite, and biotite crystallised as minor late stage minerals following high-level emplacement of Gowan Andesite and siliceous Glenham Porphyry members. Low 87 Sr/ 86 Sr ratios (c. 0.7034-0.7037), REE and multi-element distribution patterns, and the mineralogical features collectively suggest fractionation of the andesites from parental basalt originating in an enriched mantle wedge above a subduction zone, with minimal contamination by continental crust. High-K andesites appear to be unknown in clearly

  20. Bathymetric gradients within a Paleozoic Island Arc, southeastern Alaska (Alexander Terrane)

    Energy Technology Data Exchange (ETDEWEB)

    Soja, C.M. (Smith College, Northampton, MA (USA))

    1990-05-01

    Early to Late Silurian (Wenlock-Ludlow) limestones belonging to the Heceta Formation reflect bathymetric gradients within the ancient island arc exposed in the Alexander terrane of southeastern Alaska. These rocks record the earliest occurrence of widespread carbonate deposition in the region and represent the earliest foundation for shallow-water platform development within the arc. The excellent preservation of platform, platform margin, and slope deposits contrasts with the poor preservation of many marine sediments that originated within other island arcs. Hence, these limestones provide important insights into the styles, processes, and bathymetry of carbonate deposition in island arcs. Carbonate depositional sites within the arc extended laterally from nearshore intertidal and relatively shallow subtidal zones of a marine platform, to the seaward margins of a rimmed shelf, and into deeper subtidal areas of a slope environment. Fossiliferous deposits that originated on the platform comprise a diversity of shelly benthos, including corals and stromatoporoids in growth position. Dasycladacean algae, oncoids, and Amphipora also indicate shallow-water conditions. Organic buildups and reefs were constructed by cyanobacteria, massive stromatoporoids, corals, and algae at the platform margin. Deposition beyond the seaward edge of the shelf is evident from the carbonate turbidites that consist of skeletal debris of shallow-water derivation and an absence of coarse siliciclastic detritus. Sedimentation and resedimentation along a bathymetric gradient within the arc is especially well illustrated by the carbonate breccias that are enclosed within these deep subtidal sediments. They comprise detached stromatolites and clasts of shallow-water origin that were derived from the platform and its margin during periodic slumping of the shelf edge.

  1. Ultramafic Terranes and Associated Springs as Analogs for Mars and Early Earth

    Science.gov (United States)

    Blake, David; Schulte, Mitch; Cullings, Ken; DeVincezi, D. (Technical Monitor)

    2002-01-01

    Putative extinct or extant Martian organisms, like their terrestrial counterparts, must adopt metabolic strategies based on the environments in which they live. In order for organisms to derive metabolic energy from the natural environment (Martian or terrestrial), a state of thermodynamic disequilibrium must exist. The most widespread environment of chemical disequilibrium on present-day Earth results from the interaction of mafic rocks of the ocean crust with liquid water. Such environments were even more pervasive and important on the Archean Earth due to increased geothermal heat flow and the absence of widespread continental crust formation. The composition of the lower crust and upper mantle of the Earth is essentially the-same as that of Mars, and the early histories of these two planets are similar. It follows that a knowledge of the mineralogy, water-rock chemistry and microbial ecology of Earth's oceanic crust could be of great value in devising a search strategy for evidence of past or present life on Mars. In some tectonic regimes, cross-sections of lower oceanic crust and upper mantle are exposed on land as so-called "ophiolite suites." Such is the case in the state of California (USA) as a result of its location adjacent to active plate margins. These mafic and ultramafic rocks contain numerous springs that offer an easily accessible field laboratory for studying water/rock interactions and the microbial communities that are supported by the resulting geochemical energy. A preliminary screen of Archaean biodiversity was conducted in a cold spring located in a presently serpentinizing ultramafic terrane. PCR and phylogenetic analysis of partial 16s rRNA, sequences were performed on water and sediment samples. Archaea of recent phylogenetic origin were detected with sequences nearly identical to those of organisms living in ultra-high pH lakes of Africa.

  2. Precambrian Terranes of African affinities in the southeastern part of Brazil and Uruguay

    International Nuclear Information System (INIS)

    Preciozzi, F.; Basei, M.; Siga Junior, H.; Sato, K.; Kaufuss, G.

    2006-01-01

    The interest in correlating terranes at opposite margins of the South Atlantic Ocean reflects a natural curiosity of both researchers who work in the eastern South-America and who study southwestern Africa. On a large scale scenario the geology of this region is characterized by a central portion composed of Neoproterozoic-Cambrian belts (Dom Feliciano, Kao ko, Damara, Gariep, Saldania) having on each side old gneissic-migmatitic terrains on both continents (Luis Alves, Rio de La Plata, Kalahari and Congo). In South America the Neoproterozoic Dom Feliciano Belt (DFB) predominates in the eastern part of the region and is internally organized according to three different crustal segments characterized, from southeast to northwest, by a Granite belt (deformed I-type medium to high calc-alkaline granites and alkaline granitoid rocks; a Schist belt (volcano-sedimentary rocks metamorphosed from green schist to amphibolite facies and intrusive granitoids), and a Fore land basin (anchimetamorphic sedimentary and volcanic rocks), the latter situated between the Schist belt and the Archean-Paleoproterozoic fore land. Despite discontinuously covered by younger sediments, the NS continuity of these three crustal segments is suggested by similar lithotypes, structural characteristics, ages and isotopic signature, as well as by the gravimetric data. The Major Gercino, Cordilheira, and Sierra Ballena shear zones are part of the major NE-SW lineaments that affect all southern Brazilian and Uruguayan Precambrian terrains. They separate the Dom Feliciano Schist Belt (supra crustal rocks of the Brusque-Porongos and Lavalleja groups), to the West, from the granitoids of the Granite belt, to the East. The shear zones are characterized by a regional NE trend and a resultant oblique direction of movement where ductile-brittle structures predominate

  3. A geologic guide to Wrangell-Saint Elias National Park and Preserve, Alaska; a tectonic collage of northbound terranes

    Science.gov (United States)

    Winkler, Gary R.; with contributions by MacKevett, E. M.; Plafker, George; Richter, D.H.; Rosenkrans, D.S.; Schmoll, H.R.

    2000-01-01

    Wrangell-Saint Elias National Park and Preserve, the largest unit in the U.S. National Park System, encompasses near 13.2 million acres of geological wonderments. This geologic guide presents history of exploration and Earth-science investigation; describes the complex geologic makeup; characterizes the vast college of accretion geologic terranes in this area of Alaska's continental margin; recapitulates the effects of earthquakes, volcanoes, and glaciers; characterizes the copper and gold resources of the parklands; and describes outstanding locales within the park and preserve area. A glossary of geologic terms and a categorized list of additional sources of information complete this report.

  4. Late Cretaceous tectonothermal evolution of the southern Lhasa terrane, South Tibet: Consequence of a Mesozoic Andean-type orogeny

    Science.gov (United States)

    Dong, Xin; Zhang, Ze-ming; Klemd, Reiner; He, Zhen-yu; Tian, Zuo-lin

    2018-04-01

    The Lhasa terrane of the southern Tibetan Plateau participated in a Mesozoic Andean-type orogeny caused by the northward subduction of the Neo-Tethyan oceanic lithosphere. However, metamorphic rocks, which can unravel details of the geodynamic evolution, are rare and only exposed in the south-eastern part of the Lhasa terrane. Therefore, we conducted a detailed petrological, geochemical and U-Pb zircon geochronological study of the late Cretaceous metamorphic rocks and associated gabbros from the Nyemo inlier of the southern Lhasa terrane. The Nyemo metamorphic rocks including gneisses, schists, marbles and calc-silicate rocks, experienced peak amphibolite-facies contact metamorphism under P-T conditions of 3.5-4.0 kbar and 642-657 °C with a very high geothermal gradient of 45-50 °C/km, revealing a distinct deflection from the steady-state geotherm during low-pressure metamorphism. Inherited magmatic zircon cores from the metamorphic rocks yielded protolith ages of 197-194 Ma, while overgrowth zircon rims yielded metamorphic ages of ca. 86 Ma. Whole-rock chemistry and zircon Hf isotopes suggest that the protoliths of the gneisses and schists are andesites and tuffs of the early Jurassic Sangri Group, which were derived from a depleted mantle source of a continental arc affinity. The coeval intimately-associated gabbro (ca. 86 Ma) crystallized under P-T conditions of 3.5-5.3 kbar and 914-970 °C, supplying the heat flux high enough to cause the contact metamorphism of the Sangri Group rock types. We propose that the intrusion of the gabbro and a simultaneous pressure increase of up to 4.0 kbar, which is related to crustal thickening due to crustal overthrusting and the intrusion of mafic material, resulted in the late Cretaceous metamorphism of the early Jurassic Sangri Group during an Andean-type orogeny. Furthermore the Nyemo metamorphic rocks, which have previously been considered to represent slivers of the Precambrian metamorphic basement of the Lhasa terrane

  5. Comparison of Conventional, Trace Element, and Pseudosection Thermobarometry in UHP Eclogite, North Qaidam Terrane, Western China

    Science.gov (United States)

    Mattinson, C. G.; Regel, M. E.; Zhang, J.

    2014-12-01

    In the southeastern North Qaidam terrane, near Dulan, felsic host gneisses enclose minor eclogite lenses. A small (~3°C/km) increase in temperatures to the west based on Zr-in-Rt thermometry is supported by a textural trend of zoned garnet with prograde mineral inclusions in the west to unzoned garnet with only peak-stage inclusions in the east. A western eclogite sample contains minor Ep and trace Phe in addition to Grt-Omp-Qtz-Rt; a strong foliation is defined by banding of Grt and Omp. Garnet Ca falls significantly from core (Alm44Prp23Grs32) to rim (Alm48Prp27Grs23). Phengite contains 3.34-3.36 Si pfu. Conventional Grt-Omp-Phe thermobarometry yields 23-27 kbar, 660-730°C, and Zr-in-Rt thermometry yields 671 ± 9°C (n = 37). An isochemical phase diagram (pseudosection) for the system NCKFMASHO calculated with PerpleX indicates that garnet Xgrs decreases with increasing P and T, suggesting that observed garnet zoning reflects prograde growth. Garnet rim compositional isopleths intersect at 23-27 kbar, 580-620°C, depending on choice of effective bulk composition and assumed Fe3+/Fetotal. Garnet rims help define the foliation, suggesting that these P-T conditions apply to this deformation. An eastern eclogite sample contains minor Ep and abundant, coarse-grained Phe in addition to Grt-Omp-Qtz-Rt; foliation is weak. Garnet zoning is weak; compositions are Alm41-43Prp26-28Grs29-32. Phengite cores contain 3.48-3.56 Si pfu. Conventional Grt-Omp-Phe thermobarometry yields 32-36 kbar, 700-750°C, and Zr-in-Rt thermometry yields 691 ± 12°C (n = 34). Conventional thermobarometry and pseudosections yield similar peak P-T conditions, but from different mineral compositions: thermobarometry yields peak P from high-Ca Grt, but the pseudosection yields peak P from intermediate-Ca Grt; maximum Ca in Grt is predicted at lower P and T. Pseudosection-based peak Ts are significantly lower than those from Zr-in-Rt and conventional thermometry. Wide isopleth spacing in the

  6. Geology of the Severnaya Zemlya Archipelago and the North Kara Terrane in the Russian high Arctic

    Science.gov (United States)

    Lorenz, Henning; Männik, Peep; Gee, David; Proskurnin, Vasilij

    2008-05-01

    The Severnaya Zemlya Archipelago is located at 80°N near the continental shelf break, between the Kara and Laptev seas. Sedimentary successions of Neoproterozoic and Palaeozoic age dominate the bedrock geology. Together with Northern Tajmyr, Severnaya Zemlya constitutes the main land areas of the North Kara Terrane (NKT), which is inferred here to have been a part of the Timanide margin of Baltica, i.e. an integral part of Baltica at least since the Vendian. Vendian turbidites derived from the Timanide Orogen are inferred to have been deposited on Neoproterozoic greenschist facies, granite-intruded basement. Shallow-water siliclastic deposition in the Early to Mid-Cambrian was followed by highly organic-rich shales in the Late Cambrian and influx of more turbidites. An episode of folding, the Kan’on River deformation, separates these formations from the overlying Tremadocian conglomerates and sandstones. In the Early Ordovician, rift-related magmatic rocks accompanied the deposition of variegated marls, sandstones, carbonates and evaporites. Dark shales and gypsiferous limestones characterise the Mid-Ordovician. Late Ordovician quartz-sandstones mark a hiatus, followed by carbonate rocks that extend up into and through most of the Silurian. The latter give way upwards into Old Red Sandstones, which are inferred to have been deposited in a Caledonian foreland basin. Deformation, reaching the area in the latest Devonian or earliest Carboniferous and referred to as the Severnaya Zemlya episode, is thought to be Caledonian-related. The dominating E-vergent structure was controlled by décollement zones in Ordovician evaporite-bearing strata; detachment folds and thrusts developed in the west and were apparently impeded by a barrier of Ordovician igneous rocks in the east. Below the décollement zones, the Neoproterozoic to Early Ordovician succession was deformed into open to close folds. The exposed strata in the lower structural level have been juxtaposed with

  7. Uncertainty in 14C model ages of groundwater: The influence of soil gas in terranes dominated by C3 plants

    Science.gov (United States)

    Nelson, S.; Hart, R.; Eggett, D.

    2009-12-01

    Groundwater is the largest source of fresh water readily available to humanity and aquifers with long residence times are particularly susceptible to overuse. Thus, it is important to have quantitative estimates of the residence time of water in such aquifers. Many models used to calculate 14C ages of groundwater depend on an estimate of the δ13C value of carbon dioxide in soil at the time of recharge, a value that must be estimated. Other work has suggested that for terranes dominated by C3 plants, -23‰ is an appropriate value, and sensitivity calculations show that the apparent age of a groundwater is strongly dependent on the choice of this parameter. This is especially true where the measured values of δ13C of dissolved inorganic carbon (DIC) are used to estimate the contribution of “dead” carbon to the DIC load via the dissolution of calcite in the aquifer and soil zones. To better understand the temporal and spatial isotopic and abundance variability of soil carbon dioxide, we established soil gas sampling sites that encompassed a wide variety of settings in terms of season, elevation, climate, and plant community that were sampled monthly throughout regions of the state of Utah where C3 flora dominate. Direct measurements of soil gas suggest a value of -21.8 ± 1.4‰ (1σ) is a good input variable as long as: a) C3 vegetation dominates, and b) extreme aridity does not prevail such that plant densities and soil microbial activities are minimized. If recharge is envisaged to occur during spring and early summer in highly vegetated uplands, a value of -24.0 ± 0.6‰ may be more appropriate as statistical analysis reveals that seasonality and plant density are most clearly correlated to the carbon isotope composition of carbon dioxide in soil gas. Although the two values and ranges cited above values do not diverge strongly from other published estimates, they place fairly narrow limits on the uncertainty of ±500 and ±200 yr., respectively, in

  8. Post-collisional basalts of the Acampamento Velho Formation, Camaquã Basin, São Gabriel Terrane, southernmost Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Vedana

    Full Text Available ABSTRACT: The basic volcanic rocks in the Palma region, southern portion of the São Gabriel Terrane, have always been interpreted as generated during the active subduction period of the São Gabriel orogeny (Cryogenian. This terrane was built as the result of the Charrua Ocean closure between 900-680 Ma. The basalts show a subhorizontal igneous flow foliation and porphyritic texture, with plagioclase phenocrysts in a thin matrix composed of plagioclase, augite and magnetite, commonly altered to actinolite, chlorite and epidote. They have amygdales and veinlets reflecting a pervasive hydrothermal phase and are affected by thermal metamorphism related to Jaguari granite intrusion. Two samples were dated by the U-Pb zircon geochronology and yielded crystallization ages of 563±2 Ma and 573±6 Ma. The basalts have transitional composition from tholeiitic to calc-alkaline, metaluminous character, trace elements patterns rich in large-ion lithophile element (LILE with negative anomalies of Nb, P and Ti, slight enrichment in light rare-earth elements (LREE and horizontal pattern of heavy rare earth elements (HREE. The data allow interpreting the basalts as belonging to the Acampamento Velho Formation of the Camaquã Basin, and related to the basalts of the Ramada and Taquarembó plateaus. These associations represent the final evolution of the volcanism generated in the post-collisional period of the Dom Feliciano Belt.

  9. Development and application of a soil organic matter-based soil quality index in mineralized terrane of the Western US

    Science.gov (United States)

    Blecker, S.W.; Stillings, Lisa L.; Amacher, M.C.; Ippolito, J.A.; DeCrappeo, N.M.

    2013-01-01

    Soil quality indices provide a means of distilling large amounts of data into a single metric that evaluates the soil’s ability to carry out key ecosystem functions. Primarily developed in agroecosytems, then forested ecosystems, an index using the relation between soil organic matter and other key soil properties in more semi-arid systems of the Western US impacted by different geologic mineralization was developed. Three different sites in two different mineralization types, acid sulfate and Cu/Mo porphyry in California and Nevada, were studied. Soil samples were collected from undisturbed soils in both mineralized and nearby unmineralized terrane as well as waste rock and tailings. Eight different microbial parameters (carbon substrate utilization, microbial biomass-C, mineralized-C, mineralized-N and enzyme activities of acid phosphatase, alkaline phosphatase, arylsulfatase, and fluorescein diacetate) along with a number of physicochemical parameters were measured. Multiple linear regression models between these parameters and both total organic carbon and total nitrogen were developed, using the ratio of predicted to measured values as the soil quality index. In most instances, pooling unmineralized and mineralized soil data within a given study site resulted in lower model correlations. Enzyme activity was a consistent explanatory variable in the models across the study sites. Though similar indicators were significant in models across different mineralization types, pooling data across sites inhibited model differentiation of undisturbed and disturbed sites. This procedure could be used to monitor recovery of disturbed systems in mineralized terrane and help link scientific and management disciplines.

  10. Constraints of detrital zircon U-Pb ages and Hf isotopes on the provenance of the Triassic Yidun Group and tectonic evolution of the Yidun Terrane, Eastern Tibet

    Science.gov (United States)

    Wang, Bai-Qiu; Wang, Wei; Chen, Wei Terry; Gao, Jian-Feng; Zhao, Xin-Fu; Yan, Dan-Ping; Zhou, Mei-Fu

    2013-05-01

    Eastern Tibet to the west of the Yangtze Block consists of the Yidun and Songpan-Ganzi Terranes, separated by the Ganzi-Litang suture zone. The Yidun Terrane includes the Zhongza Massif to the west, but the eastern part of the Yidun terrane is covered by the Yidun Group extending from the south (Shangri-La region) to the north (Changtai region). The Yidun Group, from the base upward, includes the Lieyi, Qugasi, Tumugou and Lanashan formations, which are mainly composed of volcanic-flysch successions. Based on the ages of volcanic interlayers and plutonic intrusions, depositional ages of the Qugasi and Tumugou formations are considered to be slightly older than 230 Ma and ca. 220-230 Ma respectively, which are prominently older than the previous estimates. The Yidun Group in the Changtai region has two prominent detrital zircon age peaks at 400-480 and 880-980 Ma and a minor peak at 2.45-2.50 Ga. This pattern suggests a detritus source from the Zhongza Massif, which was a micro-continent separated from the western Yangtze Block. In contrast, the Yidun Group in the Shangri-La region has various zircon age spectra among different formations. The Qugasi Formation in this region has detrital zircon age patterns similar to the Yidun Group in the Changtai region. However, the overlying Tumugou Formation shows distinct age peaks at Triassic (220-240 Ma), Neoproterozoic (~ 720-880 Ma), and Paleoproterozoic (~ 1.75-1.90 Ga). This age pattern is similar to that of the Xikang Group of the Songpan-Ganzi Terrane to the east. The detrital zircon age difference between the Qugasi and Tumugou formations in this region indicates a transition of sedimentary sources from the Zhongza Massif to locally distributed Triassic magmatic rocks at ~ 230 Ma. It is thus suggested that the Songpan-Ganzi Terrane may have been connected to or collided with the southern part of the Yidun Terrane during the Late Triassic, whereas the Songpan-Ganzi Terrane and the northern part of the Yidun Terrane

  11. Late Triassic porphyritic intrusions and associated volcanic rocks from the Shangri-La region, Yidun terrane, Eastern Tibetan Plateau: Adakitic magmatism and porphyry copper mineralization

    Science.gov (United States)

    Wang, Bai-Qiu; Zhou, Mei-Fu; Li, Jian-Wei; Yan, Dan-Ping

    2011-11-01

    Early Mesozoic porphyritic intrusions in the Shangri-La region, southern Yidun terrane, SW China, are spatially associated with andesites and dacites. These intrusions are composed of diorite and quartz diorite, and are closely related to copper mineralization. LA-ICP-MS zircon U-Pb ages of the intrusions range from 230 to 215 Ma. The associated andesites and dacites are interlayered with slates and sandstones and have ages of around 220 Ma. All of the intrusive and extrusive rocks have similar, highly fractionated REE patterns and high La/Yb (13-49) ratios with no prominent Eu anomalies. They display pronounced negative Nb-Ta and Ti anomalies on primitive mantle-normalized spidergrams. Their SiO2 contents range from 56.6 to 67.1 wt.%, Al2O3 from 14.2 to 17.4 wt.% and MgO from1.9 to 4.2 wt.%. All the rocks have high Sr (258-1980 ppm), and low Y (13-21 ppm) with high Sr/Y ratios (29-102). These features suggest that both the volcanic rocks and porphyritic intrusions were derived from adakitic magmas. They have similar initial 87Sr/86Sr ratios (0.7058 to 0.7077) and εNd (- 1.88 to - 4.93) values, but belong to high silica (HSA) and low silica adakitic rocks (LSA). The HSA represent an early stage of magmatism (230 to 215 Ma) and were derived from oceanic slab melts with limited interaction with the overlying mantle wedge during ascent. At 215 Ma, more extensive interaction produced the LSA. We propose that the early adakitic magmas (HSA) formed by flat subduction leading to melting of oceanic slab, whereas subsequent slab break-off caused the significant interaction between slab melts and the mantle wedge and thus the generation of the later adakitic magmas (LSA).

  12. Stratigraphy, geochronology, and accretionary terrane settings of two Bronson Hill arc sequences, northern New England

    Science.gov (United States)

    Moench, R.H.; Aleinikoff, J.N.

    2003-01-01

    the southern Laurentian margin, but northwest of the principal Iapetan suture, or Red Indian line. The Boil Mountain-Jim Pond-Hurricane Mountain sequence was ramped northwestward over the Chain Lakes massif at ???475 Ma, on the basal Boil Mountain surface. This obduction probably occurred slightly before obduction on the Baie Vert-Brompton surface (BBL), farther NW, over the Laurentian margin, and was followed by Dead River flysch sedimentation, which ended with the abrupt onset of Ammonoosuc-sequence arc magmatism at ???470 Ma. Ammonoosuc eruptions probably ended at ???460 Ma, when Iapetus closed along the Red Indian line. During a following magmatic hiatus of ???3-5 m.y., now represented by portions of the Partridge Formation that overlie the Ammonoosuc Volcanics, subduction polarity reversed, and subduction resumed below the northwest-dipping Brunswick subduction complex (BSC) of New Brunswick, Canada. Quimby-sequence magmatism (???456-435 Ma) on the newly accreted Laurentian margin occurred above the BSC, whose footwall is now buried to the southeast by mainly Silurian clastic sediments of the Merrimack-Fredericton trough, deposited in the "Fredericton Sea". In Silurian to Early Devonian time, the NW-dipping BSC footwall was paired with a SE-dipping subduction zone that produced arc magmas of the Coastal Volcanic belt, built on the composite Avalon and adjacent peri-Avalonian terranes. Orogen-normal extension produced by rapid rollback of both subduction zones narrowed the Fredericton Sea, produced the Central Maine and Connecticut Valley-Gaspe?? basins, and culminated in the Acadian orogeny when the sea completely closed in Early Devonian time. Published by Elsevier Science Ltd.

  13. Latest Paleozoic early Mesozoic structures in the central Oaxaca Terrane of southern Mexico: deformation near a triple junction

    Science.gov (United States)

    Centeno-Garcia, E.; Keppie, J. Duncan

    1999-01-01

    Paleozoic rocks in the Oaxaca Terrane of southern Mexico occur as two outliers (Rio Salinas and Santiago Ixtaltepec) unconformably overlying the 1-Ga Oaxaca Complex. They consist of the Upper Cambrian-Lower Ordovician Tiñu Formation, Mississippian Santiago Formation, lower-middle Pennsylvanian Ixtaltepec Formation and the unfossiliferous Yododeñe Formation of presumed Permian or younger age. These Paleozoic rocks have been deformed by several sets of structures. Three moderately westerly-dipping, bedding-parallel shear zones displaying dextral kinematic indicators (C-S fabrics, curvilinear isoclinal folds, en-echelon boudinage, en-echelon veins, and strained amygdales) occur along the boundaries between the Tiñu and Santiago formations, between the Santiago and Ixtaltepec formations, and within the Ixtaltepec Formation in the Santiago Ixtaltepec outlier. The bedding and these bedding-parallel shear zones are deformed by N-S, upright-asymmetric, subhorizontal folds accompanied by a slaty or spaced cleavage, that are in turn deformed by several sets of kink bands: subhorizontal and steeply dipping E-W, NW-SE and NE-SW. In the northern part of the Santiago Ixtaltepec outlier, the stratigraphy, bedding-parallel shear zones and slaty cleavage are displaced by NW-SE normal faults, all of which are truncated by the angular unconformity at the base of the Cretaceous, which brackets their age as post-Early Permian and pre-Cretaceous. Geometric correlation of the major N-S folds with E-vergent thrusting of the Oaxacan Complex over the Juarez Terrane suggests that they are older than Middle Jurassic. No age constraints are available for the kink and chevron folds; however, most may be related to Laramide structures in the overlying Cretaceous rocks. Unfolding the major structures in the Paleozoic rocks reorients the bedding-parallel shear zones to subhorizontal detachment shear zones or faults with a top-to-the-north sense of displacement. They may be related to either

  14. Pre-Cenozoic History of the Jalisco Block (Guerrero Terrane of West-Central Mexico) From U- Pb Geochronology

    Science.gov (United States)

    Valencia, V. A.; Righter, K. O.; Gehrels, G.; Ruiz, J.; Ducea, M.; Rosas-Helguera, J.

    2007-05-01

    The Jalisco Block is a fault-bounded crustal fragment, located along the western edge of the Trans-Mexican Volcanic Belt of west-central Mexico, and it forms part of the Triassic-Jurassic Guerrero terrane. Because of its extensive Miocene-Quaternary volcanic cover and Early Cretaceous-Tertiary intrusions, little is known about its Pre-Tertiary history. U-Pb (LA-MC-ICPMS) zircon geochronology of metasedimentary (Quartz Feldespathic Schist), marine sedimentary and plutonic rocks from several localities of the Jalisco Block (southern Mexico) were determined to constrain the geological evolution of this region. Results for the metasedimentary rocks, which are present as roof pendants, indicate a depositional age between the Late Triassic and Middle Jurassic. The older depositional sequence (Late Triassic) shows an important continental influence with subordinate clusters from the Carboniferous (297 Ma), Ordovician (446 Ma), Late and Middle Proterozoic (760, 1041, 1200, 1500 Ma) and Archean (~~2700 Ma), whereas the youngest depositional sequence (Middle Jurassic) have mainly Jurassic zircons, indicating sedimentation in a restricted basin. Ages of turbiditic marine sediments reveal a maximum depositional age of ~~130 Ma (Early Cretaceous), comparable to zircon populations from other areas of the Guerrero Terrane, and with minor age peaks at 320, 480-560, 743, 997-1260, and ~~2750 Ma. Magmatic granitic rocks from Atenguillo, Puerto Vallarta, Mascota and Tomatlan have ages of ~~60 Ma, ~~74 Ma and 80-90 Ma. These ages overlap with previously determined ages of granites and rhyolitic ash flow tuffs from the Jalisco Block, Baja California, Sonora and Sinaloa states. On the other hand, a granitic sample of Cuale region yielded a middle Jurassic age. Metasedimentary and sedimentary rocks of the Jalisco Block have a depositional evolution similar to coeval formations in the Guerrero and Alisitos terranes. We conclude that this

  15. Cenozoic mantle composition evolution of southern Tibet indicated by Paleocene ( 64 Ma) pseudoleucite phonolitic rocks in central Lhasa terrane

    Science.gov (United States)

    Qi, Yue; Gou, Guo-Ning; Wang, Qiang; Wyman, Derek A.; Jiang, Zi-Qi; Li, Qiu-Li; Zhang, Le

    2018-03-01

    The question of whether continental subduction processes in collisional orogenic belts can trigger wide-spread mantle metesomatism and crustal material recycling remains unresolved. Miocene (25-8 Ma) ultrapotassic rocks in southern Tibet are the only mantle-derived magmatic rocks emplaced after the collision between India and Asia and they have been linked to the onset of east-west extensional stresses as the surface uplift of the Tibetan Plateau reached near-maximum elevation. However, their petrogenesis remains highly controversial, particularly the issue of whether their extremely enriched Sr-Nd isotopic characteristics were related to metasomatism derived from subducted Indian continental materials during the Cenozoic. Here we report on a Paleocene silicate-unsaturated, pseudoleucite phonolitic dike, in the Rongniduo area of central Lhasa terrane. In-situ SIMS (secondary ion mass spectrometry) apatite U-Pb age indicates the dike was generated at 64.1 ± 4.2 Ma, which slightly predates the age of initial India and Asia collision (about 55-50 Ma). This is the oldest age yet reported for ultrapotassic rocks in southern Tibet. Samples from this dike have distinctly more depleted Sr-Nd (whole rock: (87Sr/86Sr)i = 0.7064 to 0.7062, εNd(t) = - 1.5 to 0.4; in situ apitite: (87Sr/86Sr)i = 0.7059 to 0.7060, εNd(t) = - 2.0 to 0.4) isotopic compositions, than those of Miocene (25-8 Ma) ultrapotassic rocks in the central Lhasa terrane ((87Sr/86Sr)i = 0.7106 to 0.7399, εNd(t) = - 10.6 to - 18.5). Our new data provides important constraints on pre-collisional mantle characteristics beneath the Lhasa terrane. We suggest that these 64 Ma pseudoleucite phonolitic rocks were derived from the enriched lithospheric mantle metasomatized by subducted Tethyan oceanic materials in response to Neo-Tethyan slab roll-back. As a consequence, the younger Miocene ultrapotassic rocks, which display different geochemical compositions from the pre-collisional ultrapotassic rocks, were most

  16. Geochronological and geochemical constraints on the origin of the Yunzhug ophiolite in the Shiquanhe-Yunzhug-Namu Tso ophiolite belt, Lhasa Terrane, Tibetan Plateau

    Science.gov (United States)

    Zeng, Yun-Chuan; Xu, Ji-Feng; Chen, Jian-Lin; Wang, Bao-Di; Kang, Zhi-Qiang; Huang, Feng

    2018-02-01

    The formation of the Shiquanhe-Yunzhug-Namu Tso ophiolite mélange zone (SNMZ) within the Lhasa Terrane, Tibetan Plateau, is key to understanding the Mesozoic tectonic evolution of this terrane, which remains controversial. We show that the Yunzhug ophiolite in the central segment of the SNMZ formed at 150 Ma, based on U-Pb dating of zircons from a gabbroic sample in a well-developed sheeted dike complex. Geochemically, these mafic rocks are dominated by E-MORB-type compositions, along with minor amounts of rocks with P-MORB-type compositions. The samples also exhibit high εNd(t) values and lack negative Nb and Ta anomalies. Data for all the samples plot within the MORB array on a Th/Yb-Nb/Yb diagram. Therefore, these mafic rocks most likely formed in either a slow spreading oceanic setting or an embryonic ocean, and not in a back-arc basin as has been previously assumed. Taking into account the regional geology, we propose that the Yunzhug ophiolite is part of a distinct ophiolitic belt and represents material formed in an embryonic ocean within the Lhasa Terrane, which provides new insights into the Jurassic tectonic evolution of the Lhasa Terrane.

  17. U-Pb detrital zircon geochronology from the basement of the Central Qilian Terrane: implications for tectonic evolution of northeastern Tibetan Plateau

    Science.gov (United States)

    Liu, Changfeng; Wu, Chen; Zhou, Zhiguang; Yan, Zhu; Jiang, Tian; Song, Zhijie; Liu, Wencan; Yang, Xin; Zhang, Hongyuan

    2018-03-01

    The Tuolai Group dominates the Central Qilian Terrane, and there are different opinions on the age and tectonic attribute of the Tuolai Group. Based on large-scale geologic mapping and zircon dating, the Tuolai Group is divided into four parts: metamorphic supracrustal rocks, Neoproterozoic acid intrusive rocks, early-middle Ordovician acid intrusive rocks and middle Ordovician basic intrusive rocks. The metamorphic supracrustal rocks are the redefined Tuolai complex-group and include gneiss and schist assemblage by faulting contact. Zircon U-Pb LA-MC-ICP-MS dating was conducted on these samples of gneiss and migmatite from the gneiss assemblage, quartzite, two-mica schist and slate from the schist assemblage. The five detrital samples possess similar age spectra; have detrital zircon U-Pb main peak ages of 1.7 Ga with youngest U-Pb ages of 1150 Ma. They are intruded by Neoproterozoic acid intrusive rocks. Therefore, the Tuolai Group belonging to late Mesoproterozoic and early Neoproterozoic. With this caveat in mind, we believe that U-Pb detrital zircon dating, together with the geologic constraints obtained from this study and early work in the neighboring regions. We suggest that the formation age of the entire crystalline basement rocks of metasedimentary sequence from the Central Qilian Terrane should be constrained between the Late Mesoproterozoic and the Late Neoproterozoic, but not the previous Paleoproterozoic. The basement of the Central Qilian Terrane contains the typical Grenville ages, which indicates the Centre Qilian Terrane have been experienced the Grenville orogeny event.

  18. U-Pb detrital zircon geochronology from the basement of the Central Qilian Terrane: implications for tectonic evolution of northeastern Tibetan Plateau

    Science.gov (United States)

    Liu, Changfeng; Wu, Chen; Zhou, Zhiguang; Yan, Zhu; Jiang, Tian; Song, Zhijie; Liu, Wencan; Yang, Xin; Zhang, Hongyuan

    2017-08-01

    The Tuolai Group dominates the Central Qilian Terrane, and there are different opinions on the age and tectonic attribute of the Tuolai Group. Based on large-scale geologic mapping and zircon dating, the Tuolai Group is divided into four parts: metamorphic supracrustal rocks, Neoproterozoic acid intrusive rocks, early-middle Ordovician acid intrusive rocks and middle Ordovician basic intrusive rocks. The metamorphic supracrustal rocks are the redefined Tuolai complex-group and include gneiss and schist assemblage by faulting contact. Zircon U-Pb LA-MC-ICP-MS dating was conducted on these samples of gneiss and migmatite from the gneiss assemblage, quartzite, two-mica schist and slate from the schist assemblage. The five detrital samples possess similar age spectra; have detrital zircon U-Pb main peak ages of 1.7 Ga with youngest U-Pb ages of 1150 Ma. They are intruded by Neoproterozoic acid intrusive rocks. Therefore, the Tuolai Group belonging to late Mesoproterozoic and early Neoproterozoic. With this caveat in mind, we believe that U-Pb detrital zircon dating, together with the geologic constraints obtained from this study and early work in the neighboring regions. We suggest that the formation age of the entire crystalline basement rocks of metasedimentary sequence from the Central Qilian Terrane should be constrained between the Late Mesoproterozoic and the Late Neoproterozoic, but not the previous Paleoproterozoic. The basement of the Central Qilian Terrane contains the typical Grenville ages, which indicates the Centre Qilian Terrane have been experienced the Grenville orogeny event.

  19. Post-Nevadan deformation along the Bear Mountains fault zone: Implications for the Foothills terrane, central Sierra Nevada, California

    Science.gov (United States)

    Paterson, Scott R.; Tobisch, Othmar T.; Radloff, Judith K.

    1987-06-01

    Southern parts of the Foothills terrane, Sierra Nevada, California, consist of western and eastern sequences of volcanic rocks and overlying slate-gray wacke units separated by a multiply deformed and lithologically chaotic central belt. Structural and strain studies suggest that the intensity of regional ductile deformation decreased from greater than 50% shortening in the western belt to less than 30% shortening in the eastern belt and that much of this ductile deformation is younger than the timing usually assumed for the Nevadan orogeny. These structures are in turn deformed by a large ductile shear zone representing the southern continuation of the Bear Mountains fault zone. This shear zone separates the western and central belts, has an oblique east-over-west sense of movement, and deforms the western margin of the Guadalupe igneous complex. These observations suggest that the eastern and western volcanic sequences are pieces of arcs amalgamated along the Bear Mountains fault zone during and after Nevadan deformation.

  20. Delineating the major KREEP-bearing terranes on the moon with global measurements of absolute thorium abundances

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, D.J.; Feldman, W.C.; Barraclough, B.L.; Elphic, R.C.; Prettyman, T.H. [Los Alamos National Lab., NM (United States); Binder, A.B. [Lunar Research Inst., Gilroy, CA (United States); Maurice, S. [Observatoire Midi-Pyrenees, Toulouse (France); Miller, M.C. [Lawrence Livermore National Lab., CA (United States)

    1999-03-01

    The Lunar Prospector (LP) Gamma-Ray Spectrometer (GRS) has been used to map the global composition of thorium on the lunar surface. Previous LP results of relative thorium abundances demonstrated that thorium is highly concentrated in and around the nearside western maria and less so in the South Pole Aitken (SPA) basin. Using new detector modeling results and a larger data set, the authors present here a global map of absolute thorium abundances on a 2{degree} by 2{degree} equal-area pixel scale. Because thorium is a tracer of KREEP-rich material, these data provide fundamental information regarding the locations and importance of terranes that are rich in KREEP bearing materials.

  1. Paleoproterozoic (ca. 1.8 Ga) arc magmatism in the Lützow-Holm Complex, East Antarctica: Implications for crustal growth and terrane assembly in erstwhile Gondwana fragments

    Science.gov (United States)

    Takahashi, Kazuki; Tsunogae, Toshiaki; Santosh, M.; Takamura, Yusuke; Tsutsumi, Yukiyasu

    2018-05-01

    The Lützow-Holm Complex (LHC) of East Antarctica forms a part of the latest Neoproterozoic-Cambrian high-grade metamorphic segment of the East African-Antarctic Orogen. Here we present new petrological, geochemical, and zircon U-Pb geochronological data on meta-igneous rocks from four localities (Austhovde, Telen, Skallevikshalsen, and Skallen) in the LHC, and evaluate the regional Paleoproterozoic (ca. 1.8 Ga) arc magmatism in this terrane for the first time. The geochemical features reveal a volcanic-arc affinity for most of the meta-igneous rocks from Austhovde and Telen, suggesting that the protoliths of these rocks were derived from felsic to mafic arc magmatic rocks. The protoliths of two mafic granulites from Austhovde are inferred as non-volcanic-arc basalt such as E-MORB, suggesting the accretion of remnant oceanic lithosphere together with the volcanic-arc components during the subduction-collision events. The weighted mean 206Pb/238U ages of the dominant population of magmatic zircons in felsic orthogneisses from Austhovde and Telen show 1819 ± 19 Ma and 1830 ± 10 Ma, respectively, corresponding to Paleoproterozoic magmatic event. The magmatic zircons in orthogneisses from other two localities yield upper intercept ages of 1837 ± 54 Ma (Skallevikshalsen), and 1856 ± 37 Ma and 1854 ± 45 Ma (Skallen), which also support Paleoproterozoic magmatism. The earlier thermal events during Neoarchean to Early Paleoproterozoic are also traced by 206Pb/238U ages of xenocrystic zircons in the felsic orthogneisses from Austhovde (2517 ± 17 Ma and 2495 ± 15 Ma) and Telen (2126 ± 16 Ma), suggesting partial reworking of the basement of a 2.5 Ga microcontinent during ca. 1.8 Ga continental-arc magmatism. The timing of peak metamorphism is inferred to be in the range of 645.6 ± 10.4 to 521.4 ± 12.0 Ma based on 206Pb/238U weighted mean ages of metamorphic zircon grains. The results of this study, together with the available magmatic ages as well as geophysical and

  2. The influence of upper-crust lithology on topographic development in the central Coast Ranges of California

    Science.gov (United States)

    Garcia, A.F.; Mahan, S.A.

    2012-01-01

    A fundamental geological tenet is that as landscapes evolve over graded to geologic time, geologic structures control patterns of topographic distribution in mountainous areas such that terrain underlain by competent rock will be higher than terrain underlain by incompetent rock. This paper shows that in active orogens where markedly weak and markedly strong rocks are juxtaposed along contacts that parallel regional structures, relatively high topography can form where strain is localized in the weak rock. Such a relationship is illustrated by the topography of the central Coast Ranges between the Pacific coastline and the San Andreas fault zone (SAFZ), and along the length of the Gabilan Mesa (the "Gabilan Mesa segment" of the central Coast Ranges). Within the Gabilan Mesa segment, the granitic upper crust of the Salinian terrane is in contact with the accretionary-prism m??lange upper crust of the Nacimiento terrane along the inactive Nacimiento fault zone. A prominent topographic lineament is present along most of this lithologic boundary, approximately 50 to 65. km southwest of the SAFZ, with the higher topography formed in the m??lange on the southwest side of the Nacimiento fault. This paper investigates factors influencing the pattern of topographic development in the Gabilan Mesa segment of the central Coast Ranges by correlating shortening magnitude with the upper-crust compositions of the Salinian and Nacimiento terranes. The fluvial geomorphology of two valleys in the Gabilan Mesa, which is within the Salinian terrane, and alluvial geochronology based on optically-stimulated luminescence (OSL) age estimates, reveal that the magnitude of shortening accommodated by down-to-the-southwest tilting of the mesa since 400ka is less than 1 to 2m. Our results, combined with those of previous studies, indicate that at least 63% to 78% of late-Cenozoic, northeast-southwest directed, upper-crustal shortening across the Gabilan Mesa segment has been accommodated

  3. Raman spectroscopy of detrital garnet from the (U)HP terrane of eastern Papua New Guinea

    Science.gov (United States)

    Andò, Sergio; Baldwin, Suzanne L.; Fitzgerald, Paul G.; Malusà, Marco G.; Aliatis, Irene; Vezzoli, Giovanni; Garzanti, Eduardo

    2013-04-01

    adjacent to orogenic systems, Raman-assisted heavy-mineral studies allow us to detect the first arrival of eclogitic garnet, and thus to assess the minimum age of exhumation and final unroofing of high-pressure rocks (Malusà et al., 2011; Malusà and Garzanti, 2012). However, in the (U)HP terrane of southeastern Papua New Guinea, sediments derived from the actively exhuming D'Entrecasteaux Island core complexes are still being deposited offshore, are rarely preserved sub-aerially, and as such stratigraphic constraints are limited. Raman analysis of detrital garnets from placer sand thus provides invaluable constraints to compare with mineral assemblages preserved in exhumed eclogites. REFERENCES Andò S., Bersani D., Vignola P., Garzanti E. 2009. Raman spectroscopy as an effective tool for high-resolution heavy-mineral analysis: Examples from major Himalayan and Alpine fluvio-deltaic systems. Spectrochim. Acta A73:450-455. Andò S., Morton A., Garzanti E. 2013. Metamorphic grade of source rocks revealed by chemical fingerprints of detrital amphibole and garnet. Geol. Soc. London Spec. Publ. Sediment Provenance Studies in Hydrocarbon Exploration & Production. Baldwin S.L., Monteleone B., Webb L.E., Fitzgerald P.G., Grove M., Hill E.J. 2004. Pliocene eclogite exhumation at plate tectonic rates in eastern Papua New Guinea. Nature 431:263-267. Baldwin S.L., Webb L.E., Monteleone B.D. 2008. Late Miocene coesite-eclogite exhumed in the Woodlark Rift. Geology 36:735-738 Bersani D., Andò S., Vignola P., Moltifiori G., Marino I.G., Lottici P.P., Diella V., 2009. Micro-Raman spectroscopy as a routine tool for garnet analysis. Spectrochim. Acta A73:484-491. Hill E.J., Baldwin S.L. 1993. Exhumation of high-pressure metamorphic rocks during crustal extension in the D'Entrecasteaux region, Papua New Guinea. J. Metam. Geol. 11:261-277. Malusà M.G., Faccenna C., Garzanti E., Polino R. 2011. Divergence in subduction zones and exhumation of high-pressure rocks (Eocene Western Alps

  4. New Geochronology and Radiometric Age Dates Improve the Definition and Continuity of Accreted Tectonic Terranes of Northern Venezuela and the Lesser Antilles

    Science.gov (United States)

    Baquero, M.; Mann, P.; Audemard, F. A.

    2017-12-01

    We use new and compiled geochronology and radiometric dates from the area of Venezuela to Tobago to define the following crustal provinces: 1) Guyana shield forms a sub-circular area of Pan-African rocks against which all younger terranes have collided and partially assumed its rounded shape: ages for the Guyana Shield range from >3.4 Ga to 1.8 Ga; 2) accreted Paleozoic rocks form a sub-circular, largely buried province that surround the Guiana Shield to the north and west; the El Pilar strike-slip fault forms the abrupt, northern limit of the Precambrian-Paleozoic craton in Venezuela characterized by crustal thicknesses of 40-50 km; 3) the Early to Late Cretaceous Great Arc of the Caribbean forms a continuous basement high that can be traced from northern Colombia, through the ABC Islands to La Blanquilla Island, and north along the Aves Ridge to the Greater Antilles; ages of the GAC generally are in the range of Late Cretaceous to early Eocene and have geochemistry consistent with intra-oceanic island arcs or oceanic plateau rocks with the exception of La Orchila Island with a Paleozoic intrusive age; the GAC collided from west to east with the passive margin of South America from Paleocene in western Venezuela to Plio-Pleistocene in the Trinidad area and marks the west to east passage of the Caribbean plate past the South American plate; 4) a post-GAC rifting event affected the GAC-South America suture from late Eocene to middle Miocene time in the Falcón Basin of western Venezuela with ages on intrusive and volcanic from 34 to 15.4 Ma; these ages are coeval with intrusive ages from the southernmost Lesser Antilles on Los Frailes and Los Testigos Islands and range from 35.7±2.6 to 36.4±0.5 Ma; the age of the intervening basin, the Bonaire basin, is poorly known but may be coeval with the Oligocene-Miocene extension that extended the suture zone in western Venezuela and extended the Lesser Antilles arc in early Middle Miocene time to form the Lesser Antilles

  5. Timing of the final closure of the Paleo-Asian Ocean in the Alxa Terrane: Constraints from geochronology and geochemistry of Late Carboniferous to Permian gabbros and diorites

    Science.gov (United States)

    Liu, Qian; Zhao, Guochun

    2017-04-01

    The Alxa Terrane is a crucial place situated between the North China Craton to the east and the Tarim Craton to the west. The Late Paleozoic magmatic record in the Alxa Terrane places important constraints on the timing of the final closure of the middle segment of the Paleo-Asian Ocean (PAO). In this study, new LA-ICPMS zircon U-Pb dating results reveal ca. 300-268 Ma gabbros and diorites in the Bayan Nuru area in the eastern part of the Alxa Terrane. The 300 Ma gabbros show plagioclase accumulations with anorthite compositions (An92-95), arc-like geochemical affinities with relative enrichment in large ionic lithophile elements and depletion in high field strength elements (e.g., Ti, Nb and Ta), as well as negative Hf(t) (-6.01 to -1.75) and Nd(t) (-9.5 to -7.1) values and high initial 87Sr/86Sr ratios (0.707157-0.707220). These features indicate a magma source of an enriched lithospheric mantle metasomatized by high fluid activities. In comparison, the 280-268 Ma gabbros and diorites also have arc-like geochemical affinities but show increasingly evolved isotope compositions, implying more sediment inputs. Compiled zircon ɛHf(t) and whole-rock ɛNd(t) values of the magmatic rocks in the Alxa Terrane decrease from the Late Carboniferous to the Early Permian, and increase from the Middle Permian to the Triassic. The considerably large spread in ɛHf(t) and ɛNd(t) values at ca. 280-265 Ma likely reflects a tectonic switch from a subduction setting to a post-collisional setting, corresponding to the timing of the final closure of the PAO in the Alxa Terrane. Thus, the PAO progressively closed from west to east along the northern margin of the Tarim Craton, the Alxa Terrane, and then the northern margin of the North China Craton during Late Carboniferous to Middle Triassic time. This work was financially supported by a NSFC Project (41190075) entitled "Final Closure of the Paleo-Asian ocean and Reconstruction of East Asian Blocks in Pangea", the fifth

  6. The Cannery Formation--Devonian to Early Permian arc-marginal deposits within the Alexander Terrane, Southeastern Alaska

    Science.gov (United States)

    Karl, Susan M.; Layer, Paul W.; Harris, Anita G.; Haeussler, Peter J.; Murchey, Benita L.

    2011-01-01

    cherts on both Admiralty and Kupreanof Islands contain radiolarians as young as Permian, the age of the Cannery Formation is herein extended to Late Devonian through early Permian, to include the early Permian rocks exposed in its type locality. The Cannery Formation is folded and faulted, and its stratigraphic thickness is unknown but inferred to be several hundred meters. The Cannery Formation represents an extended period of marine deposition in moderately deep water, with slow rates of deposition and limited clastic input during Devonian through Pennsylvanian time and increasing argillaceous, volcaniclastic, and bioclastic input during the Permian. The Cannery Formation comprises upper Paleozoic rocks in the Alexander terrane of southeastern Alaska. In the pre-Permian upper Paleozoic, the tectonic setting of the Alexander terrane consisted of two or more evolved oceanic arcs. The lower Permian section is represented by a distinctive suite of rocks in the Alexander terrane, which includes sedimentary and volcanic rocks containing early Permian fossils, metamorphosed rocks with early Permian cooling ages, and intrusive rocks with early Permian cooling ages, that form discrete northwest-trending belts. After restoration of 180 km of dextral displacement of the Chilkat-Chichagof block on the Chatham Strait Fault, these belts consist, from northeast to southwest, of (1) bedded chert, siliceous argillite, volcaniclastic turbidites, pillow basalt, and limestone of the Cannery Formation and the Porcupine Slate of Gilbert and others (1987); (2) greenschist-facies Paleozoic metasedimentary and metavolcanic rocks that have Permian cooling ages; (3) silty limestone and calcareous argillite interbedded with pillow basalt and volcaniclastic rocks of the Halleck Formation and the William Henry Bay area; and (4) intermediate-composition and syenitic plutons. These belts correspond to components of an accretionary complex, contemporary metamorphic rocks, forearc-basin deposits,

  7. Thermal gradient and geochronology of a Paleozoic high-grade terrane in the northeastern Cathaysia block, South China

    Science.gov (United States)

    Zhao, Lei; Zhai, Mingguo; Zhou, Xiwen; Santosh, M.; Ma, Xudong

    2016-11-01

    The Chencai terrane in the northeastern Cathaysia Block forms part of the northeast extension of the Paleozoic orogeny in South China. Recent field investigations have revealed the occurrence of high grade rocks in this terrane including granulite facies metapelites (khondalites) and orthopyroxene-bearing granulites. However, the thermal gradients and metamorphic history of this region have not been well constrained, thus impeding a better understanding of the geodynamic history of the Paleozoic orogeny in South China. Here we report results from a systematic study on the metamorphic PT conditions and geochronology of the orthopyroxene granulites and metasedimentary rocks (metapelites) from the Chencai area. The orthopyroxene granulites preserve granulite facies peak assemblage of Opx + Grt + Pl + Kfs + Qtz and a retrograde P-T trajectory. Peak PT conditions are 845-860 °C and 0.83-0.86 Gpa, corresponding to a thermal gradient of 30 °C/km which is much hotter than the normal thermal gradient of continental crust. Mineral compositions of the metasedimentary rocks re-equilibrated during retrograde metamorphism so that the peak PT conditions recorded by these rocks are much lower than those obtained from the orthopyroxene granulite. Peak PT conditions are 710-720 °C, 0.57-0.58 Gpa for garnet-biotite gneiss and 760-780 °C, 0.60-0.62 Gpa for biotite garnetite. Zircon U-Pb dating shows that this episode of granulite facies metamorphism occurred at 430-450 Ma and the detrital population shows minor or no contribution from the basement rocks of the Cathaysia Block. The Neoproterozoic rocks occurring along the Jiangnan belt are considered to have provided the sedimentary source as indicated by the two main age peaks of 0.79 Ga and 0.83 Ga from the detrital zircon cores. Lu-Hf isotope data on the zircons indicates extensive alteration and little new zircon growth during the Paleozoic metamorphism. The εHf(t) values and model ages (TDM1) of zircons suggest that the

  8. Kinematics of Post-Collisional Extensional Tectonics and Exhumation of the Menderes Massif in the Western Anatolia Extended Terrane, Turkey

    Science.gov (United States)

    Cemen, I.; Catlos, E. J.; Diniz, E.; Gogus, O.; Ozerdem, C.; Baker, C.; Kohn, M. J.; Goncuoglu, C.; Hancer, M.

    2006-12-01

    The Western Anatolia Extended Terrane in Turkey is one of the best-developed examples of post-collisional extended terranes and contains one of the largest metamorphic core complexes in the world, the Menderes massif. It has experienced a series of continental collisions from the Late Cretaceous to the Eocene as the Neotethys Ocean closed and the Izmir-Ankara-Erzincan suture zone was formed. Based our field work and monazite ages, we suggest that the north-directed postcollisional Cenozoic extension in the region is the product of three consecutive, uninterrupted stages, triggered by three different mechanisms. The first stage was initiated about 30 Ma ago, in the Oligocene by the Orogenic Collapse the thermally weakened continental crust along the north-dipping Southwest Anatolian shear zone. The shear zone was formed as an extensional simple-shear zone with listric geometry at depth and exhibits predominantly normal- slip along its southwestern end. But, it becomes a high-angle oblique-slip shear zone along its northeastern termination. Evidence for the presence of the shear zone includes (1) the dominant top to the north-northeast shear sense indicators throughout the Menderes massif, such as stretching lineations trending N10E to N30E; and (2) a series of Oligocene extensional basins located adjacent to the shear zone that contain only carbonate and ophiolitic rock fragments, but no high grade metamorphic rock fragments. During this stage, erosion and extensional unroofing brought high-grade metamorphic rocks of the central Menderes massif to the surface by the early Miocene. The second stage of the extension was triggered by subduction roll-back and associated back-arc extension in the early Miocene and produced the north-dipping Alasehir and the south-dipping Buyuk Menderes detachments of the central Menderes massif and the north-dipping Simav detachment of the northern Menderes massif. The detachments control the Miocene sedimentation in the Alasehir, Buyuk

  9. Paleomagnetism of Early Paleozoic Rocks from the de Long Archipelago and Tectonics of the New Siberian Islands Terrane

    Science.gov (United States)

    Metelkin, D. V.; Chernova, A. I.; Matushkin, N. Y.; Vernikovskiy, V. A.

    2017-12-01

    The De Long archipelago is located to the north of the Anjou archipelago as a part of a large group between the Laptev Sea and the East Siberian Sea - the New Siberian Islands and consists of Jeannette Island, Bennett Island and Henrietta Island. These islands have been shown to be part of a single continental terrane, whose tectonic history was independent of other continental masses at least since the Ordovician. Paleomagnetic and precise geological data for the De Long archipelago were absent until recently. Only in 2013 special international field trips to the De Long Islands could be organized and geological, isotope-geochronological and paleomagnetic studies were carried out.On Jeannette Island a volcanic-sedimentary sequence intruded by mafic dikes was described. The age of these dikes is more likely Early Ordovician, close to 480 Ma, as evidenced by the results of our 40Ar/39Ar and paleomagnetic investigations of the dolerites as well as the result from detrital zircons in the host rocks published before. On Bennett Island, there are widespread Cambrian-Ordovician mainly terrigenous rocks. Paleomagnetic results from these rocks characterize the paleogeographic position of the De Long archipelago at 465 Ma and perhaps at 530 Ma, although there is no evidence for the primary origin of magnetization for the latter. On Henrietta Island the Early Cambrian volcanic-sedimentary section was investigated. A paleomagnetic pole for 520 Ma was obtained and confirmed by new 40Ar/39Ar results. Adding to our previous paleomagnetic data for the Anjou archipelago the extended variant of the apparent polar wander path for the New Siberian Island terrane was created. The established paleolatitudes define its location in the equatorial and subtropical zone no higher than 40 degrees during the Early Paleozoic. Because there are no good confirmations for true polarity and related geographic hemisphere we present two possibilities for tectonic reconstruction. But both these

  10. Early Cretaceous I-type granites in the Tengchong terrane: New constraints on the late Mesozoic tectonic evolution of southwestern China

    Directory of Open Access Journals (Sweden)

    Yi Fang

    2018-03-01

    Full Text Available The Early Cretaceous granitoids that are widespread in the Tengchong terrane of Southwest China play a critical role in understanding the tectonic framework associated with the Tethyan oceans. In this study, we present a detailed description of zircon U–Pb ages, whole-rock geochemistry and Hf isotopes for the Laoxiangkeng pluton in the eastern Tengchong terrane and elucidate their petrogenesis and geodynamic implications. Zircon U–Pb dating of the Laoxiangkeng pluton yields ages of 114 ± 1 Ma and 115 ± 1 Ma, which imply an Early Cretaceous magmatic event. The Laoxiangkeng pluton enriched in Si and Na, is calc-alkaline and metaluminous, and has the characteristics of highly fractionated I-type granites. Zircons from the pluton have calculated εHf(t values of −12.7 to −3.7 and two-stage model ages of 1327–1974 Ma, respectively, indicating a mixed source of partial melting of Paleo-Neoproterozoic crust-derived compositions with some inputs of mantle-derived magmas. By integrating all available data for the regional tectonic evolution of the eastern Tethys tectonic domain, we conclude that the Early Cretaceous magmatism in the Tengchong terrane was produced by the northeastward subduction of the Meso-Tethyan Bangong–Nujiang Ocean.

  11. Ancient terrane boundaries as probable seismic hazards: A case study from the northern boundary of the Eastern Ghats Belt, India

    Directory of Open Access Journals (Sweden)

    Saibal Gupta

    2014-01-01

    Full Text Available In the eastern part of the Indian shield, late Paleozoic–Mesozoic sedimentary rocks of the Talchir Basin lie precisely along a contact of Neoproterozoic age between granulites of the Eastern Ghats Mobile Belt (EGMB and amphibolite facies rocks of the Rengali Province. At present, the northern part of the basin experiences periodic seismicity by reactivation of faults located both within the basin, and in the Rengali Province to the north. Detailed gravity data collected across the basin show that Bouguer anomalies decrease from the EGMB (∼+15 mGal, through the basin (∼−10 mGal, into the Rengali Province (∼−15 mGal. The data are consistent with the reportedly uncompensated nature of the EGMB, and indicate that the crust below the Rengali Province has a cratonic gravity signature. The contact between the two domains with distinct sub-surface structure, inferred from gravity data, coincides with the North Orissa Boundary Fault (NOBF that defines the northern boundary of the Talchir Basin. Post-Gondwana faults are also localized along the northern margin of the basin, and present-day seismic tremors also have epicenters close to the NOBF. This indicates that the NOBF was formed by reactivation of a Neoproterozoic terrane boundary, and continues to be susceptible to seismic activity even at the present-day.

  12. Confirmation of the southwest continuation of the Cat Square terrane, southern Appalachian Inner Piedmont, with implications for middle Paleozoic collisional orogenesis

    Science.gov (United States)

    Huebner, Matthew T.; Hatcher, Robert D.; Merschat, Arthur J.

    2017-01-01

    Detailed geologic mapping, U-Pb zircon geochronology and whole-rock geochemical analyses were conducted to test the hypothesis that the southwestern extent of the Cat Square terrane continues from the northern Inner Piedmont (western Carolinas) into central Georgia. Geologic mapping revealed the Jackson Lake fault, a ∼15 m-thick, steeply dipping sillimanite-grade fault zone that truncates lithologically distinct granitoids and metasedimentary units, and roughly corresponds with a prominent aeromagnetic lineament hypothesized to represent the southern continuation of the terrane-bounding Brindle Creek fault. Results of U-Pb SHRIMP geochronology indicate Late Ordovician to Silurian granitoids (444–439 Ma) occur exclusively northwest of the fault, whereas Devonian (404–371 Ma) granitoids only occur southeast of the fault. The relatively undeformed Indian Springs granodiorite (three individual bodies dated 317–298 Ma) crosscuts the fault and occurs on both sides, which indicates the Jackson Lake fault is a pre-Alleghanian structure. However, detrital zircon signatures from samples southeast of the Jackson Lake fault reveal dominant Grenville provenance, in contrast to Cat Square terrane detrital zircon samples from the northern Inner Piedmont, which include peri-Gondwanan (600–500 Ma) and a prominent Ordovician-Silurian (∼430 Ma) signature. We interpret the rocks southeast of the Jackson Lake fault to represent the southwestern extension of the Cat Square terrane primarily based on the partitioning of granitoid ages and lithologic distinctions similar to the northern Inner Piedmont.Data suggest Cat Square terrane metasedimentary rocks were initially deposited in a remnant ocean basin setting and developed into an accretionary prism in front of the approaching Carolina superterrane, ultimately overridden by it in Late Devonian to Early Mississippian time. Burial to >20 km resulted in migmatization of lower plate rocks, forming an infrastructure beneath the

  13. Cryogenian alkaline magmatism in the Southern Granulite Terrane, India: Petrology, geochemistry, zircon U-Pb ages and Lu-Hf isotopes

    Science.gov (United States)

    Santosh, M.; Yang, Qiong-Yan; Ram Mohan, M.; Tsunogae, T.; Shaji, E.; Satyanarayanan, M.

    2014-11-01

    The Southern Granulite Terrane (SGT) in India preserves the records of the formation and recycling of continental crust from Mesoarchean through Paleoproterozoic to Neoproterozoic and Cambrian, involving multiple subduction-accretion-collision associated with major orogenic cycles. A chain of unmetamorphosed and undeformed alkaline magmatic intrusions occurs along the northern margin of the SGT aligned along paleo-suture zones. Here we investigate two representative plutons from this suite, the Angadimogar syenite (AM) and the Peralimala alkali granite (PM) through field, petrological, geochemical, zircon U-Pb and Lu-Hf studies. Magma mixing and mingling textures and mineral assemblages typical of alkaline rocks are displayed by these plutons. The whole-rock major and trace element data characterize their alkaline nature. In trace element discrimination diagrams, the AM rocks straddle between the VAG (volcanic-arc granites) and WPG (within plate granites) fields with most of the samples confined to the VAG field, whereas the PM rocks are essentially confined to the WPG field. The diversity in some of the geochemical features between the two plutons is interpreted to be the reflection of source heterogeneities. Most zircon grains from the AM and PM plutons display oscillatory zoning typical of magmatic crystallization although some grains, particularly those from the PM pluton, show core-rim structures with dark patchy zoned cores surrounded by irregular thin rims resulting from fluid alteration. The weighted mean 206Pb/238U ages of the magmatic zircons from three samples of the AM syenite are in the range of 781.8 ± 3.8 Ma to 798 ± 3.6 Ma and those from two samples of the PM alkali granite yield ages of 797.5 ± 3.7 Ma and 799 ± 6.2 Ma. A mafic magmatic enclave from the AM pluton shows weighted mean 206Pb/238U age of 795 ± 3.3 Ma. The AM and PM plutons also carry rare xeneocrystic zircons which define upper intercept concordia ages of 3293 ± 13 Ma and 2530

  14. Timing, Controls and Tectonic Context of Gold Mineralisation in the Southern Uplands-Longford-Down Terrane, Caledonides, Scotland and Ireland.

    Science.gov (United States)

    Rice, Samuel; Cuthbert, Simon; Hursthouse, Andrew

    2017-04-01

    The relationships between regional tectonic, magmatic and metamorphic events and hydrothermal mineralisation in orogenic settings are controversial [1]. The geotectonic development of the Caledonian orogenic belt of the northern British Isles, which hosts some significant gold deposits, is well-constrained and provides an excellent framework for investigating these relationships. Gold mineralisation at two of the best known deposits, Curraghinalt and Cononish, located in the Grampian Terrane, has recently been shown to have occurred between 462.7 and 452.8 Ma, during the Late Ordovician Grampian event of the Caledonian orogeny [2]. In the Southern Uplands-Longford-Down Terrane syn and post-kinnematic intrusions constrain the age of mineralisation to between 418 and 397 Ma. Mineralisation is hosted by late Caledonian transverse D3 structures of Early Devonian age [3]. Fluid inclusion data indicate that the auriferous quartz veins were deposited from a low salinity carbonic mesothermal ( 330°C) fluid of apparently mixed magmatic-metamorphic origin, consistent with a Caledonian orogenic origin [4-6]. Gold mineralisation is associated with contemporaneous minor intrusions at several localities [7-9] exhibiting comparable mineralogy, geochemistry, fluid inclusion types and structural relationships, indicating that coeval regional magmatism may have been a significant factor for all of the deposits. Gold mineralisation in the SULDT occurred during a transition from compression to strike-slip deformation coeval with a regional pulse of orogenic magmatism [10]. The common association between gold deposits in Phanerozoic orogenic settings and intrusions may explain overlapping characteristics between orogenic, intrusion-related and porphyry gold deposits and may reflect the important role of magmatism in conveying the heat to drive hydrothermal systems at shallow crustal levels. Further work will focus on constraining the sources of mineralising fluids and metals. 1

  15. A transect through the base of the Bronson Hill Terrane in western New Hampshire

    Science.gov (United States)

    Walsh, Gregory J.; Valley, Peter M.; Sicard, Karri R.; Thompson, Thelma Barton; Thompson, Peter J.

    2012-01-01

    This trip will present the preliminary results of ongoing bedrock mapping in the North Hartland and Claremont North 7.5-minute quadrangles in western New Hampshire. The trip will travel from the Lebanon pluton to just north of the Sugar River pluton (Fig. 1) with the aim of examining the lower structural levels of the Bronson Hill anticlinorium (BHA), and the nature of the boundary with the rocks of the Connecticut Valley trough (CVT). Spear and others (2002, 2003, 2008) proposed that western New Hampshire was characterized by five major faults bounding five structural levels including, from lowest to highest, the “chicken yard line”, Western New Hampshire Boundary Thrust, Skitchewaug nappe, Fall Mountain nappe, and Chesham Pond nappe. Lyons and others (1996, 1997) showed the lowest level cored by the Cornish nappe and floored by the Monroe fault. Thompson and others (1968) explained the geometry of units by folding without major thrust faults, and described the second level as the Skitchewaug nappe. This trip will focus on the two lowest levels which we have revised to call the Monroe and Skitchewaug Mountain thrust sheets. Despite decades of geologic mapping in the northeastern United States at various scales, little 1:24,000-scale (or larger scale) modern bedrock mapping has been published for the state of New Hampshire. In fact, of the New England states, New Hampshire contains the fewest published, modern bedrock geologic maps. Conversely, adjacent Vermont has a relatively high percentage of modern bedrock maps due to focused efforts to create a new state-wide bedrock geologic map over the last few decades. The new Vermont map (Ratcliffe and others, 2011) has identified considerable gaps in our knowledge of the bedrock geology in adjacent New Hampshire where published maps are, in places, more than 50 years old and at scales ranging from 1:62,500 to 1:250,000. Fundamental questions remain concerning the geology across the Connecticut River, especially in

  16. The Dom Feliciano belt (Brazil-Uruguay)and its fore land (Rio de la Plata Craton): framework, tectonic evolution and correlations with similar terranes of southwestern Africa

    International Nuclear Information System (INIS)

    Basei, M.; Siga, O.; Masquelin, H.; Harara, O.; Reis Neto, J.; Preciozzi, F.

    2000-01-01

    The Dom Feliciano Belt (DFB) stretches for ca. 1,200 km along southeastern Brazil and eastern Uruguay, with an average width of 150 km. From its northern limit in Santa Catarina to its termination m Uruguay, DFB is internally organized according three crustal segments characterized, from southeast to northwest, by a Granitoid belt (calci-alkaline to alkaline granitoid rocks deformed to different degrees); a Schist belt (volcano-sedimentary rocks metamorphosed from green schist to amphibolite facies), and a Fore land belt (sedimentary and anchimetamorphic volcanic rocks), the latter situated between the Schist belt and the old western terranes. Despite discontinuously covered by younger sediments, the continuity of these three segments is suggested by the similar lithotypes and structural characteristics, as well as by the gravimetric geophysical signature.In this work, DBF is interpreted as the product of successive subduction s and collisions related to the agglutination of different terranes generated or intensely reworked from the Neoproterozoic to the Cambrian, during the Brasiliano and Rio Doce orogenesis, with maximum time starting at 900 Ma (opening of the Adamastor Ocean) and ending at 530 Ma (deformation of the fore land basins) related to the tecto no-magmatic events associated with the formation of the Western Gondwana.Besides the Neoproterozoic DFB and its fore land, the Rio de la Plata Craton and the Luis Alves Microplate, constituted by Paleoproterozoic gneissic-migmatitic rocks, two other tectonic units can be recognized in southeastern Brazil and eastern Uruguay: the Sao Gabriel Block (RS) where Neoproterozoic juvenile material can be characterized in regional scale (in great part associated with an island are), and the Punta del Este Terrane, which presents, in southern Uruguay, an ortho gneiss basement with ages around 1,000 Ma and a meta sedimentary cover (Rocha Group), which can correspond in the South-American portion, to the Namaqua and Gariep

  17. Draa Sfar, Morocco: A Visean (331 Ma) pyrrhotite-rich, polymetallic volcanogenic massive sulphide deposit in a Hercynian sediment-dominant terrane

    OpenAIRE

    Marcoux , Eric; Belkabir , Abdelhay; Gibson , Harold L.; Lentz , David; Ruffet , Gilles

    2008-01-01

    International audience; Draa Sfar is a Visean, stratabound, volcanogenic massive sulphide ore deposit hosted by a Hercynian carbonaceous, black shale-rich succession of the Jebilet terrane, Morocco. The ore deposit contains 10 Mt grading 5.3 wt.% Zn, 2 wt.% Pb, and 0.3 wt.% Cu within two main massive sulphides orebodies, Tazakourt (Zn-rich) and Sidi M'Barek (Zn–Cu rich). Pyrrhotite is by far the dominant sulphide (70 to 95% of total sulphides), sphalerite is fairly abundant, chalcopyrite and ...

  18. Paleomagnetic constraints on early collisional deformation along the eastern margin of the Qiantang terrane (Tibetan plateau) at 50 and 37 Ma.

    Science.gov (United States)

    Roperch, Pierrick; Dupont-Nivet, Guillaume; Guillot, Stéphane; Goussin, Fanny; Huang, Wentao; Replumaz, Anne; Yang, Zhang; Guo, Zhaojie; Song, Bowen

    2017-04-01

    Ongoing controversies on the timing and latitude of the India-Asia collision with associated formation of the Tibetan plateau have major implications on geodynamic, climatic and biotic models. Rock paleomagnetic inclinations and declinations enable in principle to quantify respectively paleolatitudes and tectonic rotations. However, shallow paleomagnetic inclinations observed for most of the Cenozoic rocks across the active belts of Central Asia have been controversially interpreted as resulting from non dipolar geomagnetic fields, inclination flattening in the sedimentary data or large scale continental deformation. In addition tectonic rotations from the Eastern margin of Tibet may result from extrusion or dextral shear associated with implication on the early collision. We present new paleomagnetic results from two Cenozoic basins of the Eastern part of the Qiantang block characterized by two short-lived volcanic fields at 37-38Ma (Nangqian area) and 49-51Ma (Xialaxiu area). In the Xialaxiu area, we sampled the volcanic field near the town of Xialaxiu and red beds filling the Sangalaxiu basin 10 to 20km farther north. Results from the red beds after tilt correction (D=328.3°, I=34.3°, α95=7.6°) confirm the result (D=322.0°, I=32.3°, α95=9.5°) previously obtained by Cogne et al., (1999) but the age and nature of the characteristic magnetization are uncertain. The mean direction calculated from 21 sites in volcanic rocks provides a more reliable paleofield (D=11.9°, I=41.6°, α95=8.0°). Comparison with the expected direction for stable Eurasia suggest no rotation but significant post 50 Ma shortening north of the Qiantang block in agreement with results from the Lhasa terrane at the same age (56-47 Ma) (van Hinsbergen et al., 2012). In the Nangqian basin, paleomagnetic sites have been collected in red beds sediments, sills and dikes intruding the red bed sequence and in extrusive volcanic rocks mainly found on top of the sedimentary sequence. A well

  19. On the Paleotectonic Evolution of the Pacific Margin of Southern Mexico, the Maya and Juchatengo Terranes and Chochal Formation Guatemala:Insights from Paleomagnetic and Isotopic Studies

    Science.gov (United States)

    Guerrero Garcia, J. C.; Herrero-Bervera, E.

    2009-05-01

    In the paleogeographic reconstruction of Mexico and northern Central America, evidence shows that the entire region is a collage of suspect terranes transported from abroad, whose timing and sense of motion are now beginning to be understood. Among these, the Chortis block and the Baja California Peninsula have been proposed as pieces of continent separated from the Pacific coast of southwestern Mexico, that have moved either southeastward by the Farallon plate or northwestward by the Kula plate. Isotopic mineral ages from coastal granites along the coast from Puerto Vallarta, Jalisco (80 Ma) to Puerto Angel, Oaxaca (11 Ma) record systematic decrease of cooling ages from NW to SE. These results also constrain the position of the Kula- Farallon spreading axis north of Puerto Vallarta. Previous studies mainly confined to the northern margin of the Chortis block, confirmed a left-lateral displacement of 130 km in Neogene time. Further studies suggested times of detachment increased to 30 Ma, 40 Ma, and 66 Ma. We conclude that several indicators, namely: (a) the truncated nature of the Pacific coast of SW Mexico; (b) the genesis of the Kula-Farallon ridge at 85 Ma; (c) the 2,600 km of northward transport of Baja British Columbia from the present-day latitude of the Baja California Peninsula, beginning at 85 Ma; (d) the paleomagnetic counterclockwise rotations of areas both in the Chortis block and along the Mexican coast, during Late Cretaceous-Paleogene time, and (e) the systematic NW-SE decrease of radiometric dates beginning at 85 Ma in Puerto Vallarta and ending at approximately 11 Ma in Puerto Angel, Oaxaca , point to this time and region for the onset of strike-slip drifting of the Chortis block toward its current position. On the other hand, in the reconstruction of past movements of tectonic plates, the determination of reliable paleomagnetic poles is of utmost importance. To achieve accurate results, a full knowledge of the rock magnetic properties of the

  20. Recycling of Amazonian detrital zircons in the Mixteco terrane, southern Mexico: Paleogeographic implications during Jurassic-Early Cretaceous and Paleogene times

    Science.gov (United States)

    Silva-Romo, Gilberto; Mendoza-Rosales, Claudia Cristina; Campos-Madrigal, Emiliano; Morales-Yáñez, Axél; de la Torre-González, Alam Israel; Nápoles-Valenzuela, Juan Ivan

    2018-04-01

    In the northeastern Mixteco terrane of southern Mexico, in the Ixcaquixtla-Atzumba region, the recycling of Amazonian detrital zircons records the paleogeography during the Mesozoic period in the context of the breakup of Pangea, a phenomenon that disarticulated the Sanozama-La Mora paleo-river. The clastic units of southern Mexico in the Ayuquila, Otlaltepec and Zapotitlán Mesozoic basins, as well as in the Atzumba Cenozoic basin, are characterized by detrital zircon contents with ages specific to the Amazonian craton, ranging between 3040 and 1278 Ma. The presence of zircons of Amazonian affinity suggests a provenance by recycling from carrier units such as the La Mora Formation or the Ayú Complex. In the area, the Ayú and Acatlán complexes form the Cosoltepec block, a paleogeographic element that during Early Cretaceous time acted as the divide between the slopes of the paleo-Gulf of Mexico and the paleo-Pacific Ocean. The sedimentological characteristics of the Jurassic-Cenozoic clastic successions in the Ixcaquixtla-Atzumba region denote relatively short transport in braided fluvial systems and alluvial fans. In this way, several basins are recognized around the Cosoltepec block. At the southeastern edge of the Cosoltepec block, the Ayuquila and Tecomazúchil formations accumulated in the Ayuquila continental basin on the paleo-Pacific Ocean slope. On the other hand, within the paleo-Gulf of Mexico slope, in the Otlaltepec continental basin, the Piedra Hueca and the Otlaltepec formations accumulated. The upper member of the Santa Lucía Formation accumulated in a transitional environment on the southwestern shoulder of the Zapotitlán basin, as well as on the paleo-Gulf of Mexico slope. In the Ayuquila basin, a marine transgression is recognized that advanced from south to north during the Late Jurassic. At the northeastern edge of the Cosoltepec block, we propose that the Santa Lucía formation attests to a transgression from the paleo-Gulf of Mexico

  1. The basement of the Punta de Este Terrane: A meso proterozoic heritage at the eastern border of Rio de La Plata craton

    International Nuclear Information System (INIS)

    Preciozzi, F.; Peel, E.; Sanchez, L.; Basei, M.

    2005-01-01

    U-Pb zircon ages between 1000 and 900 Ma corresponding to the nuclei of zircon crystals extracted from the basement of the Punta del Este Terrane (Eastern Uruguay) allowed the correlation of the protoliths of this domain with rocks attributed to the Namaqua Belt in Southwestern Africa. SHRIMP ages obtained for the ortho gneissic rocks allowed to place at ca. 750 Ma the generations of gneisses and migmatites. Differently from what occurred in Africa, reworking of this crustal segment during the Brasiliano-Pan african orogenesis was very intense, reaching the granulite facies around 640Ma. Acid volcanic and volcaniclastic rocks (Sierra de Aguirre Formation) with ages around 570 Ma, late sedimentary basins (San Carlos Formation) and post-tectonic granitoids (Santa Teresa and José Ignacio batholith s) mark the end of the events related with the Brasiliano/Pan-African orogenesis. The final collision between the Punta del Este Terrane and the western domains represented by the Dom Feliciano Belt and the Río de La Plata Craton may have occurred at around 535 Ma

  2. Kyanite Formation and Element Fractionation in the High-Al Eclogites from the Sulu UHP Metamorphic Terrane

    Directory of Open Access Journals (Sweden)

    Yung-Hsin Liu

    2010-01-01

    Full Text Available Eclogite compositions are critical parameters for under standing chemical evolution in the Earth, particularly in subduction zones. A group of eclogites from the Sulu ultra-high pres sure (UHP metamorphic terrane in eastern China shows uncommon petrographic and compositional features. They are characterized by (1 zoisite porphyroblasts coexisting with inclusion-free, inclusion-containing, and net work kyanite, (2 high Al2O3 of 18.4 - 29.2% with high MgO of 8.59 - 11.3%, and (3 intensive HFSE-REE fractionations represented by [Zr/Sm]ch and [Ti/Gd]ch ratios of 0.1 - 3.9 and 1.1 - 9.0, respectively. High-pressure fluids played a major role on developing these features. Kyanite shows two textural varieties. KyI is inclusion-free and in apparent textural equilibrium with gar net and omphacite, implying formation from plagioclase break down. KyII includes kyanite networks and porphyroblasts; the former occurs mostly in gar net, whereas the latter encloses gar net and omphacite grains. KyII were crystallized at the expense of gar net and omphacite during eclogite-fluid interaction. The low [HREE]ch ratios of 1 - 2 indicate that the protoliths were arc cumulates. The well-de fined in verse Al2O3-SiO2 and Al2O3-CaO correlations are not the characteristics of igneous precursors; there fore, must reflect metamorphic modifications. The comparison to mafic cumulates shows that the low-Al samples are compositionally better representatives of protoliths. Mass balance calculations point to anolivine gabbronoritic protolith. The intensive HFSE-REE fractionations reflect compositional differences between two sample groups. Group I samples have superchondritic HFSE-REE ratios [(Nb/La, Zr/Sm, Ti/Gdch = 2 - 7] with depletions in LREE. In contrast, group II samples show HFSE depletions and LREE enrichments. These compositional differences were explained as reflecting element mobility during eclogite-fluid inter action. Released at temperatures > 750°C, the high

  3. The relative and absolute chronology of strato-tectonic events in the Gorom-Gorom granitoid terrane and Oudalan-Gorouol belt, northeast Burkina Faso

    Science.gov (United States)

    Tshibubudze, Asinne; Hein, Kim A. A.; McCuaig, T. Campbell

    2015-12-01

    The integration of field mapping and analytical studies of magmatic units of the northeast of Burkina Faso has provided new information on the tectonic and magmatic evolution of the Oudalan-Gorouol belt and the Gorom-Gorom granitoid terrane. Structural, geochemical and geochronological analyses have helped to clarify the geological evolution of the region during the Tangaean Event (D1) and Eburnean Orogeny (D2) through to the Wabo Tampelse Event (D3). Further to this, zircon U-Pb geochronology data have demonstrated that the Oudalan-Gorouol belt and the Gorom-Gorom granitoid terrane represents some of the oldest outcropping geology in the Palaeoproterozoic Baoulé-Mossi domain recognised to date, with the oldest age at 2253 ± 9 Ma. The geochronology and geology suggests that the basement or a pre-Birimian crust to the Birimian Supergroup may be found in the northeast of Burkina Faso. The Eburnean Orogeny in the northeastern Burkina is preceded by the two phases of deformation (D1-x and D1), and two phases of magmatism. D1-x is associated with the emplacement of the Dori Batholith at the onset of D1 (2164-2141 Ma). D1 ductile-brittle deformation formed F1 folds and discrete high-strained mylonite zones that deformed the Oudalan-Gorouol belt and the Gorom-Gorom granitoid terrane during a southwest-directed palaeo-principal transport direction. The pre-Birimian to Birimian supracrustal rocks and intrusions were regionally metamorphosed during D1 to greenschist to amphibolite facies. The Eburnean Orogeny (2130-1980 Ma) is characterised by northwest-southeast shortening; it was followed by north-northwest to south-southeast shortening with development of sinistral strike-slip faults and shears. D2 brittle-(ductile) deformation is manifested by refolding of F1 by northeast-trending F2, and development of a pervasive northeast-trending S2 to S2-C foliation. Metamorphic grade attained greenschist facies during D2 with development of the mineral assemblage of quartz

  4. Map Showing Geologic Terranes of the Hailey 1°x2° Quadrangle and the western part of the Idaho Falls 1°x2° Quadrangle, south-central Idaho

    Data.gov (United States)

    Department of the Interior — The paper version of Map Showing Geologic Terranes of the Hailey 1°x2° Quadrangle and the western part of the Idaho Falls 1°x2° Quadrangle, south-central Idaho was...

  5. Regional framework and geology of iron oxide-apatite-rare earth element and iron oxide-copper-gold deposits of the Mesoproterozoic St. Francois Mountains Terrane, southeast Missouri

    Science.gov (United States)

    Day, Warren C.; Slack, John F.; Ayuso, Robert A.; Seeger, Cheryl M.

    2016-01-01

    This paper provides an overview on the genesis of Mesoproterozoic igneous rocks and associated iron oxide ± apatite (IOA) ± rare earth element, iron oxide-copper-gold (IOCG), and iron-rich sedimentary deposits in the St. Francois Mountains terrane of southeast Missouri, USA. The St. Francois Mountains terrane lies along the southeastern margin of Laurentia as part of the eastern granite-rhyolite province. The province formed during two major pulses of igneous activity: (1) an older early Mesoproterozoic (ca. 1.50–1.44 Ga) episode of volcanism and granite plutonism, and (2) a younger middle Mesoproterozoic (ca. 1.33–1.30 Ga) episode of bimodal gabbro and granite plutonism. The volcanic rocks are predominantly high-silica rhyolite pyroclastic flows, volcanogenic breccias, and associated volcanogenic sediments with lesser amounts of basaltic to andesitic volcanic and associated subvolcanic intrusive rocks. The iron oxide deposits are all hosted in the early Mesoproterozoic volcanic and volcaniclastic sequences. Previous studies have characterized the St. Francois Mountains terrane as a classic, A-type within-plate granitic terrane. However, our new whole-rock geochemical data indicate that the felsic volcanic rocks are effusive derivatives from multicomponent source types, having compositional similarities to A-type within-plate granites as well as to S- and I-type granites generated in an arc setting. In addition, the volcanic-hosted IOA and IOCG deposits occur within bimodal volcanic sequences, some of which have volcanic arc geochemical affinities, suggesting an extensional tectonic setting during volcanism prior to emplacement of the ore-forming systems.The Missouri iron orebodies are magmatic-related hydrothermal deposits that, when considered in aggregate, display a vertical zonation from high-temperature, magmatic ± hydrothermal IOA deposits emplaced at moderate depths (~1–2 km), to magnetite-dominant IOA veins and IOCG deposits emplaced at shallow

  6. Advanced Land Observing Satellite (ALOS) Phased Array Type L-Band Synthetic Aperture Radar (PALSAR) mosaic for the Kahiltna terrane, Alaska, 2007-2010

    Science.gov (United States)

    Cole, Christopher J.; Johnson, Michaela R.; Graham, Garth E.

    2015-01-01

    The U.S. Geological Survey (USGS) has initiated a multi-disciplinary study investigating the applicability of remote sensing technologies for geologic mapping and identification of prospective areas for base and precious metal deposits in remote parts of Alaska. The Kahiltna terrane in southwestern Alaska was selected for investigation because of its known mineral deposits and potential for additional mineral resources. An assortment of technologies is being investigated to aid in remote analysis of terrain, and includes imaging spectroscopy (hyperspectral remote sensing), high spatial resolution electro-optical imagery, and Synthetic Aperture Radar (SAR). However, there are significant challenges to applying imaging spectroscopy and electro-optical imagery technologies in this area because of the low solar angle for parts of the year, seasonal periods of darkness and snow cover, and the frequently cloudy weather that characterizes Alaska. Synthetic Aperture Radar (SAR) was selected because this technology does not rely on solar illumination and has all-weather capability.

  7. Mantle accretion evidence during the neoproterozoic of the Pernambuco-Alagoas terrane, and its significance to the evolution of the Borborema Province, NE Brazil

    International Nuclear Information System (INIS)

    Silva Filho, A.F.; Guimaraes, I.P; Van Schmus, W.R

    2001-01-01

    The Borborema Province is located in NE Brazil, corresponding to the western part of a major fold belt, which extends from Brazil to West Africa. According to paleogeographic reconstruction, it is located between the Congo, Sao Francisco and West Africa cratons. The Pernambuco-Alagoas Terrane is a major tectonic unit of the Borborema Province and comprises high-grade metamorphic sequences and the greatest granitic batholiths of this province. The granitic batholiths Maribondo-Correntes, Buique-Paulo Afonso and Aguas Belas-Caninde and their ortho derived country rocks show metaluminous and peraluminous compositions, and εNd(0,60 Ga) between +3,2 and -2,0 and T DM between 0,90 Ga and 1,20 Ga. These Nd isotope data favour a crustal evolution hypothesis involving accretion of juvenile material at least during the Brasiliano orogenesis collision and perhaps the formation of a juvenile lithosphere during the end of the Mesoproterozoic (au)

  8. Petrogenesis, U-Pb and Sm-Nd geochronology of the Furna Azul Migmatite: partial melting evidence during the San Ignacio Orogeny, Paragua Terrane, SW Amazon Craton

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Newton Diego Couto do; Ruiz, Amarildo Salina; Pierosan, Ronaldo; Lima, Gabrielle Aparecida de; Matos, Joao Batista; Lafon, Jean-Michel; Moura, Candido Augusto Veloso, E-mail: newtongeologia@hotmail.com, E-mail: asruiz@gmail.com, E-mail: ronaldo.pierosan@yahoo.com.br, E-mail: gabilimagel@gmail.com, E-mail: lafonjm@ufpa.br, E-mail: prof.jmatos@gmail.com, E-mail: candido@ufpa.br [Universidade Federal do Para (GEOCIAM/UFPA), Belem, PA (Brazil). Instituto Nacional de Ciencia e Tecnologia de Geociencias da Amazonia

    2016-11-01

    The Furna Azul Migmatite is a ∼10 km{sup 2} complex located in Pontes e Lacerda city, Mato Grosso, Brazil. It belongs to Paragua Terrane, limit with Rio Alegre Terrane, southeast of San Ignacio Province, in Amazon Craton. It consists of transitional metatexites with amphibolite enclaves and dioritic injections. The rocks were divided in residuum rich and leucosome rich; both have three deformation phases marked by folded stromatic layers affected by spaced foliation and metamorphosed in amphibolite facies, represented by garnet, biotite, sillimanite, and by the clinopyroxene in the enclaves. The metamorphic retrograde to greenschist is marked by formation of chlorite, muscovite and prehnite. Residuum-rich metatexites show higher CaO and Na{sub 2}O contents, separating them from K{sub 2}O, Ba and Rb enriched transitional metatexites. U-Pb on zircon and Sm-Nd whole-rocks dating indicates that the residuum-rich metatexite crystallized at 1436 ± 11 Ma, with a T{sub DM} age of 1.90 Ga and ε{sub Nd(1.43)} of -0.54, whereas the dioritic injection crystallized at 1341,7 ± 17 Ma with a T{sub DM} age of 1.47 Ga and ε{sub Nd(1.34)} of 3.39. These results indicate that the Furna Azul Migmatite protolith was formed during the San Ignacio Orogeny and was reworked during the same orogeny, as basement for collisional to post-magmatic granites from Pensamiento Intrusive Suite. (author)

  9. The Ranging and Nanosatellite Guidance Experiment (RANGE)

    OpenAIRE

    Gunter, Brian C.; Davis, Byron; Lightsey, Glenn; Braun, Robert D.

    2016-01-01

    The Ranging And Nanosatellite Guidance Experiment (RANGE) cubesat mission was recently selected for a flight opportunity as part of the Skybox University Cubesat Partnership, with a tentative launch date scheduled for 2016. The RANGE mission involves two 1.5U cubesats flying in a leader-follower formation with the goal of improving the relative and absolute positioning capabilities of nanosatellites. The satellites' absolute positions will be tracked using GPS receivers synchronized with mini...

  10. Eclogite Facies Relicts and Decompression Assemblages; Evidence for the Exhumation of a Large Coherent Metabasite Block From > 40 km Depth; Central Metamorphic Terrane, Eastern Klamath Mountains, Northern California

    Science.gov (United States)

    Barrow, W. M.; Fairhurst, R. J.; Metcalf, R. V.

    2007-12-01

    Recent exhumation models for eclogite terranes have focused on the exhumation of sialic rocks. Exhumed high pressure terranes are typically > 85% - 90% sialic material with only minor amounts of mafic and ultramafic rock. Most known metabasitic eclogites are blocks in mélange rather than large coherent bodies. The Central Metamorphic terrane (CMt) is a large (~300 km3) coherent, fault-bounded package of metabasites thought to represent a remnant of a downing plate subducted in an intra-oceanic convergent margin. Thermochronology indicates that the CMt was metamorphosed and later accreted to the base of the Trinity ophiolite along the Trinity fault during Early Permian extension (Hbl and Musc 40Ar/39Ar ages of 275 Ma - 294 Ma). Previous work suggested that the peak metamorphic temperatures and pressures were ~650°C and 0.4 to 0.8 GPa (Peacock and Norris, 1989) which is consistent with the amphibolite facies mineral assemblage. Trace element data confirm the NMORB-like composition of CMt metabasite protoliths. Newly discovered relict textures, however, suggest that CMt amphibolites record much deeper subduction burial with subsequent decompression exhumation. A decompression sequence consisting of rutile cores within ilmenite crystals mantled by titanite is observed in CMt amphibolite samples. Zr-in-rutile thermometry (Watson et al., 2006) combined with experimental data for rutile stability in metabasites (Ernst and Lui, 1998) suggests that relict rutile crystals preserve early P-T conditions of ~600°C and > 1.3 GPa consistent with eclogite facies metamorphism. Transition from eclogite facies is further supported by ilmenite-plagioclase-amphibole symplectites suggesting replacement of garnet (Bhowmik and Roy, 2003) during decompression. Amphibole compositions vary significantly and reflect lower grade (low Na, Al, Ti actinolite) overprint of earlier amphibolite facies compositions (high Na, Al, Ti magnesio- hornblende). Application of the Al-Ti hornblende

  11. Two Cenozoic tectonic events of N-S and E-W extension in the Lhasa Terrane: Evidence from geology and geochronology

    Science.gov (United States)

    Huang, Feng; Xu, Ji-Feng; Chen, Jian-Lin; Wu, Jian-Bin; Zeng, Yun-Chuan; Xiong, Qiu-Wei; Chen, Xue-Feng; Yu, Hong-Xia

    2016-02-01

    Cenozoic active structures in the Tibetan Plateau are mainly regional N-S trending extensional faults and grabens, and E-W trending extensional tracks that are related to the transition from syn- to post-collision between India and Asia. E-W trending tracks are parallel to the direction of Neo-Tethyan oceanic convergence and consist of extensional volcanic-sedimentary basins and magmatic dykes in the southern Lhasa Terrane, Tibet. N-S trending tracks comprise faults and grabens, which are widely developed in Tibet. It remains unknown how and when the geodynamic transition from E-W to N-S trending tectonic tracks occurred. This study describes both E-W and N-S trending tectonic tracks identified at Dazi area of southern Lhasa Terrane, where E-W trending mafic dykes intruded a granitoid and late-stage N-S trending felsic dykes cut across E-W trending mafic dykes. Zircons from four granitoid samples yield consistent crystallization ages of ca. 60 Ma and positive εHf(t) values (~+ 9). An altered dioritic vein, which cuts the mafic dykes, yields an age of ca. 53 Ma. These new dating results indicate that E-W trending dykes, which formed due to regional N-S extension, were emplaced between 60 and 53 Ma. In addition, two N-S trending monzonitic porphyritic dykes, which cut the mafic dykes, yield U-Pb zircon ages of ca. 17 Ma with moderate positive εHf(t) values (+ 3 to + 9.6), as well as a NNE-SSW trending quartz monzonitic dyke, which cuts all other types of dykes, yields U-Pb ages of ca. 13 Ma. This suggests that E-W extension took place between 17 and 13 Ma. These results, in combination with existing age data for Gangdese granitoids and mafic magmatism, indicate the occurrence of two major extensional events at 60-53 Ma and 17-13 Ma. In turn, this implies that the transition from E-W to N-S trending tectonic and the onset of E-W extension occurred at ca. 17 Ma or slightly earlier. Paleocene granitoids have geochemical characteristics that are indicative of both

  12. Late-Proterozoic to Paleozoic history of the peri-Gondwana Calabria-Peloritani Terrane inferred from a review of zircon chronology.

    Science.gov (United States)

    Fornelli, Annamaria; Micheletti, Francesca; Piccarreta, Giuseppe

    2016-01-01

    U-Pb analyses of zircon from ten samples of augen gneisses, eight mafic and intermediate metaigneous rocks and six metasediments from some tectonic domains along the Calabria-Peloritani Terrane (Southern Italy) contribute to knowledge of peri-Gondwanan evolution from Late-Proterozoic to Paleozoic times. All samples were equilibrated under amphibolite to granulite facies metamorphism during the Variscan orogeny. The zircon grains of all considered samples preserve a Proterozoic memory suggestive of detrital, metamorphic and igneous origin. The available data fit a frame involving: (1) Neoproterozoic detrital input from cratonic areas of Gondwana; (2) Pan-African/Cadomian assemblage of blocks derived from East and West African Craton; (3) metamorphism and bimodal magmatism between 535 and 579 Ma, within an active margin setting; (4) rifting and opening of Ordovician basins fed by detrital input from the assembled Cadomian blocks. The Paleozoic basins evolved through sedimentation, metamorphism and magmatism during the Variscan orogeny involving Palaeozoic and pre-Paleozoic blocks. The Proterozoic zircon records decidedly decrease in the high grade metamorphic rocks affected by Variscan pervasive partial melting.

  13. Telemetry-Based Ranging

    Science.gov (United States)

    Hamkins, Jon; Vilnrotter, Victor A.; Andrews, Kenneth S.; Shambayati, Shervin

    2011-01-01

    A telemetry-based ranging scheme was developed in which the downlink ranging signal is eliminated, and the range is computed directly from the downlink telemetry signal. This is the first Deep Space Network (DSN) ranging technology that does not require the spacecraft to transmit a separate ranging signal. By contrast, the evolutionary ranging techniques used over the years by NASA missions, including sequential ranging (transmission of a sequence of sinusoids) and PN-ranging (transmission of a pseudo-noise sequence) whether regenerative (spacecraft acquires, then regenerates and retransmits a noise-free ranging signal) or transparent (spacecraft feeds the noisy demodulated uplink ranging signal into the downlink phase modulator) relied on spacecraft power and bandwidth to transmit an explicit ranging signal. The state of the art in ranging is described in an emerging CCSDS (Consultative Committee for Space Data Systems) standard, in which a pseudo-noise (PN) sequence is transmitted from the ground to the spacecraft, acquired onboard, and the PN sequence is coherently retransmitted back to the ground, where a delay measurement is made between the uplink and downlink signals. In this work, the telemetry signal is aligned with the uplink PN code epoch. The ground station computes the delay between the uplink signal transmission and the received downlink telemetry. Such a computation is feasible because symbol synchronizability is already an integral part of the telemetry design. Under existing technology, the telemetry signal cannot be used for ranging because its arrival-time information is not coherent with any Earth reference signal. By introducing this coherence, and performing joint telemetry detection and arrival-time estimation on the ground, a high-rate telemetry signal can provide all the precision necessary for spacecraft ranging.

  14. The Park Volcanics Group : field relations of an igneous suite emplaced in the Triassic-Jurassic Murihiku Terrane, South Island, New Zealand

    International Nuclear Information System (INIS)

    Coombs, D.S.; Cook, N.D.J.; Campbell, J.D.

    1992-01-01

    Park Volcanics Group is proposed for igneous rocks, either shallow intrusive or extrusive, emplaced in the Murihiku Terrane during Triassic-Jurassic times. The term replaces Park Intrusives of Mutch, some members of which are shown to be extrusive rather than intrusive. Formation status within the group is given to Gowan Andesite and Pinney Volcanics (new names) in western Southland, Glenham Porphyry in eastern Southland, and Barnicoat Andesite (new) in the Richmond area, Nelson. Gowan Andesite is a porphyritic feldspar two-pyroxene andesite with a glassy or microcrystalline groundmass. A suite of low-grade metavolcanic rocks which forms the main mass of Malakoff Hill and which has formerly been included in the 'Park Intrusives' is here excluded and ascribed to the Takitimu Group; representative chemical data are given. Glenham Porphyry is typically a porphyritic feldspar two-pyroxene andesite texturally similar to the Gowan Andesite but with significant geochemical differences. Two volumetrically minor members are recognised, Habukinini Trachydacite and Kenilworth Rhyolite. In the north of its outcrop area, Glenham Porphyry is emplaced on or into Late Triassic terrestrial beds; in the middle it overlies Kaihikuan (Middle Triassic) and is overlain by Otapirian (latest Triassic) marine beds; and in the southeast it is directly overlain by Ururoan (late Early to early Middle Jurassic) conglomerates and marine sandstones. Pinney Volcanics are restricted to a very few, probably one, massive conglomeratic horizon in the Oretian Stage. The commonest rock type is a two-pyroxene trachydacite, modified by very-low-grade burial metamorphism. Auto-brecciation is characteristic and rock types change over short distances. Hornblende-rich variants occur as well as more felsic varieties including rhyolite ignimbrite. These may have been erupted onto a bouldery floodplain or shallow-marine surface, but alternatively may have been mass-emplaced by debris avalanche resulting from

  15. Clinopyroxene as a key for tracing a history of crystallization and recrystallization of coronitic metagabbro in high-grade metamorphic terranes

    Science.gov (United States)

    Egorova, Svetlana; Stepanova, Alexandra

    2017-04-01

    The evaluation PT-parameters of magmatic crystallization is usually complicated for metagabbros in high-grade metamorphic terranes. Sometimes intensively metamorphosed coronitic gabbronorites preserve relics of primary magmatic mineral assemblage that could give valuable information on the conditions of melt crystallization. However, to use the composition of this relict minerals one should be sure that relict magmatic minerals in coronotic metagabbros did not change their primary composition despite the fact of high-grade metamorphic overprinting. Clinopyroxene is the most important concentrator of REE in igneous and metamorphic mafic rocks because its trace element composition is a sensitive indicator of physico-chemical conditions of the clinopyroxene-bearing-rocks formation. The Belomorian mobile belt (BMB) of the eastern part of the Fennoscandian Shield is high-garde metamorphic terrane. High-Mg coronitic metagabbronorites are widespread in BMB. In spite of metamorphic alteration at high-pressure amphibolite (to eclogite) facies conditions they often preserve relicts of primary igneous mineral assemblages that consist of olivine, orthopyroxene, clinopyroxene (augite) and plagioclase. Corona textures usually developed between mafic minerals and plagioclase. In general, coronas consist of orthopyroxene, clinopyroxene (Na-rich diopside), hornblende (with or without spinel inclusions) and garnet. Trace element composition of relict (primary-igneous?) and corona-forming (around magmatic orthopyroxene) clinopyroxenes from paleoproterozoic coronitic metagabbronorites of the BMB was studied using SIMS Cameca IMS 4f. Igneous clinopyroxenes from fresh olivine gabbronorites of age ca. 2.45 Ga in the Karelian craton were used as reference composition for igneous clinopyroxenes. The major element contents in relict clinopyroxenes from coronitic metagabbronorites determined using EDS EPMA is very similar to the igneous clinopyroxene from gabbronorites of the Karelian craton

  16. Devonian granitoids and their hosted mafic enclaves in the Gorny Altai terrane, northwestern Central Asian Orogenic Belt: crust-mantle interaction in a continental arc setting

    Science.gov (United States)

    Chen, Ming; Sun, Min

    2016-04-01

    Granitoids are a major component in the upper continental crust and hold key information on how did the continental crust grow and differentiate. This study focuses on the Yaloman intrusive complex from the Gorny Altai terrane, northwestern Central Asian Orogenic Belt (CAOB). The association of granitoids and mafic enclaves can provide important clues on the source nature, petrogenetic processes and geodynamic setting of the Yaloman intrusive complex, which in turn will shed light on the crustal evolution in the northwestern CAOB. Zircon U-Pb dating shows that the granitoids, including quartz diorites and granodiorites, were emplaced in ca. 389-387 Ma. The moderate Na2O + K2O contents and low A/CNK values indicate that these rocks belong to the sub-alkaline series with metaluminous to weakly peraluminous compositions. The granitoids yield two-stage zircon Hf model ages of ca. 0.79-1.07 Ga and whole-rock Nd model ages of ca. 0.90-0.99 Ga, respectively, implying that they were mainly sourced from Neoproterozoic juvenile crustal materials. The mafic enclaves show an almost identical crystallization age of ca. 389 Ma. The identification of coarse-grained xenocrysts and acicular apatites, together with the fine-grained texture, makes us infer that these enclaves are likely to represent magmatic globules commingled with the host magmas. The low SiO2 and high MgO contents of the mafic enclaves further suggest that substantial mantle-derived mafic melts were probably involved in their formation. Importantly, the SiO2 contents of the granitoids and mafic enclaves are well correlated with other major elements and most of the trace elements. Also a broadly negative correlation exists between the SiO2 contents and whole-rock epsilon Nd (390 Ma) values of the granitoids. Given the observation of reversely zoned plagioclases within the granitoids and the common occurrence of igneous mafic enclaves, we propose that magma mixing probably played an important role in the formation

  17. Partial melting and rapid exhumation of a Pliocene UHP terrane: CA-TIMS zircon results from Normanby Island, Papau New Guinea

    Science.gov (United States)

    DesOrmeau, J. W.; Gordon, S. M.; Little, T. A.; Bowring, S. A.

    2012-12-01

    Some ultra-high pressure (UHP) terranes contain eclogite embedded within migmatitic gneisses that preserve evidence for multiple episodes of partial melting. Understanding the mechanisms by which crustal rocks are subducted to mantle depths and subsequently exhumed requires understanding the timing of metamorphism and the timing and role of partial melting. The D'Entrecasteaux Islands of southeastern Papua New Guinea (PNG) expose Pliocene UHP eclogites contained within migmatitic host gneisses. Garnet-whole rock Lu-Hf geochronology suggests UHP metamorphism may have begun by ca. 7 Ma, and Ar-Ar thermochronology indicates that the rocks were exhumed to the surface by ca. 2 Ma; the history between 7 and 2 Ma is crucial for tectonic models of PNG. We have applied U-Pb chemical-abrasion thermal-ionization mass spectrometry (CA-TIMS) geochronology to zircons separated from granitoid intrusions within the host gneisses to better understand the timing and role of melting in the exhumation of the PNG UHP rocks. Three granodiorite intrusions were collected from Normanby Island as it has received far less study in previous investigations than the other D'Entrecasteaux Islands (Goodenough and Fergusson) and exposes the contact of the UHP-HP rocks against the structurally overlying, weakly metamorphosed rocks of the Papuan ultramafic belt (PUB). From the west side of Normanby dome in contact with the PUB, zircons from a foliated protomylonitic granodiorite sill yielded 206Pb/238U dates of ca. 4.1 Ma. In comparison, on the eastern side of Normanby dome, zircons from a weakly foliated, discordant pegmatitic dike yielded a complex array of zircon analyses and the youngest dates are ca. 4.1 Ma. The zircons extracted from these deformed intrusions are interpreted to date melt emplacement, crystallization, and zircon growth, which may be coeval with amphibolite facies (570-730 °C and ~7-12 Kbar) metamorphism recorded from Goodenough and Fergusson Islands. Zircons from a non

  18. Dryden Aeronautical Test Range

    Data.gov (United States)

    Federal Laboratory Consortium — Recently redesignated to honor Dr. Hugh L. Dryden, NASA's Dryden Aeronautical Test Range (DATR) supports aerospace flight research and technology integration, space...

  19. U-Pb SHRIMP geochronology of zircon in garnet peridotite from the Sulu UHP terrane, China: Implications for mantle metasomatism and subduction-zone UHP metamorphism

    Science.gov (United States)

    Zhang, R.Y.; Yang, J.S.; Wooden, J.L.; Liou, J.G.; Li, T.F.

    2005-01-01

    We studied the Zhimafang ultrahigh-pressure metamorphic (UHP) peridotite from pre-pilot drill hole PP-1 of Chinese Continental Scientific Drilling project in the Sulu UHP terrane, eastern China. The peridotite occurs as lens within quartofeldspathic gneiss, and has an assemblage of Ol + Opx + Cpx + Phl + Ti-clinohumite (Ti-Chu) + Grt (or chromite) ?? magnesite (Mgs). Zircons were separated from cores at depths of 152 m (C24, garnet lhezolite), 160 m (C27, strongly retrograded phlogopite-rich peridotite) and 225 m (C50, banded peridotite), and were dated by SHRIMP mass spectrometer. Isometric zircons without inherited cores contain inclusions of olivine (Fo91-92), enstatite (En91-92), Ti-clinohumite, diopside, phlogopite and apatite. The enstatite inclusions have low Al2O3 contents of only 0.04-0.13 wt.%, indicating a UHP metamorphic origin. The weighted mean 206Pb/238U zircon age for garnet lherzolite (C24) is 221 ?? 3 Ma, and a discordia lower intercept age for peridotite (C50) is 220 ?? 2 Ma. These ages are within error and represent the time of subduction-zone UHP metamorphism. A younger lower intercept age of 212 ?? 3 Ma for a foliated wehrlite (C27) was probably caused by Pb loss during retrograde metamorphism. The source of zirconium may be partially attributed to melt/fluid metasomatism within the mantle wedge. Geochronological and geochemical data confirm that the mantle-derived Zhimafang garnet peridotites (probably the most representative type of Sulu garnet peridotites) were tectonically inserted into a subducting crustal slab and subjected to in situ Triassic subduction-zone UHP metamorphism. ?? 2005 Elsevier B.V. All rights reserved.

  20. Geology, petrology, U-Pb (SHRIMP) geochronology of the Morrinhos granite - Paragua terrane, SW Amazonian craton: implications for the magmatic evolution of the San Ignacio orogeny

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Ohana; Ruiz, Amarildo Salina; Sousa, Maria Zelia Aguiar de, E-mail: ohana.geo@gmail.com, E-mail: asruiz@gmail.com, E-mail: mzaguiar@terra.com.br [Universidade Federal de Mato Grosso (UFMT), Cuiaba, MT (Brazil). Instituto de Ciencias Exatas e da Terra. Dept. de Geologia Geral; Batata, Maria Elisa Froes, E-mail: elisabatata@bol.com.br [Universidade Federal de Mato Grosso (UFMT), Cuiaba, MT (Brazil). Grupo de Pesquisa em Evolucao Crustal e Tectonica; Lafon, Jean-Michel [Universidade Federal do Para (GEOCIAM/UFPA), Belem, PR (Brazil). Inst. Nacional de Cencia e Tecnologia de Geociencias da Amazonia

    2014-09-15

    Morrinhos granite is a batholith body that is slightly elongated in the NNW direction and approximately 1,140 km{sup 2} long; it is located in the municipality of Vila Bela da Santissima Trindade of the state of Mato Grosso, Brazil, in the Paragua Terrane, Rondonian-San Ignacio Province, in the SW portion of the Amazonian Craton. This intrusion displays a compositional variation from tonalite to monzogranite, has a medium to coarse inequigranular texture and is locally porphyritic; biotite is the predominant mafic in one of the facies, and hornblende is predominant in the other, with both metamorphosed into the green schist facies. The studied rocks characterize an intermediate to acidic sequence that was formed by a subalkaline magmatism; the series is alkali-calcic to metaluminous to slightly peraluminous, and the rocks evolved through fractioned crystallization mechanisms. The structural data show two deformation phases represented by penetrative foliation (S{sub 1}) and open folds (D{sub 2}), and both phases were most likely related to the San Ignacio Orogeny. The geochronological (U-Pb SHRIMP) and isotopic (Sm-Nd) investigations of these rocks indicated a crystallization age of 1350±12Ma, T{sub DM} of approximately 1.77 Ga and εNd{sub (1.35}) with a negative value of -2.57, suggesting that their generation was related to a partial melting process of a Paleoproterozoic (Statherian) continental crust. The results herein indicate that the Morrinhos granite was generated in a continental magmatic arc in a late- to post-orogenic stage of the San Ignacio Orogeny, and it can be recognized as belonging to the Pensamiento Intrusive Suite. (author)

  1. Tracking the exhumation of a Pliocene (U)HP terrane: U-Pb and trace-element constraints from zircon, D'Entrecasteaux Islands, Papua New Guinea

    Science.gov (United States)

    DesOrmeau, Joel W.; Gordon, Stacia M.; Little, Timothy A.; Bowring, Samuel A.

    2014-10-01

    Domal structures within the D'Entrecasteaux Islands of eastern Papua New Guinea expose ultrahigh-pressure (UHP) Pliocene (5.6-4.6 Ma) eclogites and evidence for partial melting. To better interpret the (U)HP exhumation history, U-Pb geochronology and trace-element abundances were determined in zircon from variably deformed host gneiss and crystallized melt (leucosomes, sills, dikes, and plutons) from the Goodenough and Normanby Domes by ID-TIMS (isotope-dilution thermal ionization mass spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry), respectively, to constrain the timing of melt crystallization and deformation relative to UHP metamorphism. Zircons extracted from orthogneiss and deformed granodiorite sills of Normanby Dome, located ˜40 km southeast of the UHP eclogite, record HP metamorphism from 5.66 ± 0.02 to 5.04 ± 0.07 Ma, and melt crystallization at ˜4.1 Ma. Strongly deformed, layer-parallel leucosomes from Goodenough Dome, ˜20 km northwest of the UHP eclogite, began to crystallize by 3.85 ± 0.02 Ma. These dates indicate that melt crystallization began in the Goodenough and Normanby Domes within ˜0.75 m.y. of (U)HP metamorphism. The ID-TIMS dates from the orthogneiss and crystallized melt show that exhumation and cooling of the (U)HP rocks in the PNG terrane began first in the east, within Normanby Dome, then to the west, in the Goodenough Dome ˜1 m.y. later, and finally the middle dome rocks, exposed within the Mailolo Dome, cooled ˜2 m.y. after exhumation of Normanby Dome. All domes reveal synchronous crystallization of late, nondeformed melts, and final extension-driven exhumation by 1.82 ± 0.03 Ma.

  2. On Range of Skill

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Miltersen, Peter Bro; Sørensen, Troels Bjerre

    2008-01-01

    size (and doubly exponential in its depth). We also provide techniques that yield concrete bounds for unbalanced game trees and apply these to estimate the Range of Skill of Tic-Tac-Toe and Heads-Up Limit Texas Hold'em Poker. In particular, we show that the Range of Skill of Tic-Tac-Toe is more than...

  3. Home range and travels

    Science.gov (United States)

    Stickel, L.F.; King, John A.

    1968-01-01

    The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

  4. Soliton microcomb range measurement

    Science.gov (United States)

    Suh, Myoung-Gyun; Vahala, Kerry J.

    2018-02-01

    Light detection and ranging systems are used in many engineering and environmental sensing applications. Their relatively large size and cost, however, tend to be prohibitive for general use in autonomous vehicles and drones. Suh and Vahala and Trocha et al. show that optical frequency combs generated by microresonator devices can be used for precision ranging and the tracking of fast-moving objects. The compact size of the microresonators could broaden the scope for widespread applications, providing a platform for miniaturized laser ranging systems suitable for photonic integration.

  5. Antenna Pattern Range (APR)

    Data.gov (United States)

    Federal Laboratory Consortium — TheAntenna Pattern Range (APR)features a non-metallic arch with a trolley to move the transmit antenna from the horizon to zenith. At the center of the ground plane,...

  6. Atlantic Test Range (ATR)

    Data.gov (United States)

    Federal Laboratory Consortium — ATR controls fully-instrumented and integrated test ranges that provide full-service support for cradle-to-grave testing. Airspace and surface target areas are used...

  7. Detrital zircon ages in Korean mid-Paleozoic meta-sandstones (Imjingang Belt and Taean Formation): Constraints on tectonic and depositional setting, source regions and possible affinity with Chinese terranes

    Science.gov (United States)

    Han, Seokyoung; de Jong, Koen; Yi, Keewook

    2017-08-01

    Sensitive High-Resolution Ion Microprobe (SHRIMP) U-Th-Pb isotopic data of detrital zircons from mature, quartz-rich meta-sandstones are used to constrain possible tectonic affinities and source regions of the rhythmically layered and graded-bedded series in the Yeoncheon Complex (Imjingang Belt) and the correlative Taean Formation. These metamorphic marine turbidite sequences presently occur along the Paleoproterozoic (1.93-1.83 Ga) Gyeonggi Massif, central Korea's main high-grade metamorphic gneiss terrane. Yet, detrital zircons yielded highly similar multimodal age spectra with peaks that do not match the age repartition in these basement rocks, as late (1.9-1.8 Ga) and earliest (∼ 2.5 Ga) Paleoproterozoic detrital modes are subordinate but, in contrast, Paleozoic (440-425 Ma) and Neoproterozoic (980-920 Ma) spikes are prominent, yet the basement essentially lacks lithologies with such ages. The youngest concordant zircon ages in each sample are: 378, 394 and 423 Ma. The maturity of the meta-sandstones and the general roundness of zircons of magmatic signature, irrespective of their age, suggest that sediments underwent considerable transport from source to sink, and possibly important weathering and recycling, which may have filtered out irradiation-weakened metamorphic zircon grains. In combination with these isotopic data, presence of a low-angle ductile fault contact between the Yeoncheon Complex and the Taean Formation and the underlying mylonitized Precambrian basement implies that they are in tectonic contact and do not have a stratigraphic relationship, as often assumed. Consequently, in all likelihood, both meta-sedimentary formations: (1) are at least of early Late Devonian age, (2) received much of their detritus from distant (reworked) Silurian-Devonian and Early Neoproterozoic magmatic sources, not present in the Gyeonggi Massif, (3) and not from Paleoproterozoic crystalline rocks of this massif, or other Korean Precambrian basement terranes, and

  8. Range Selection and Median

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Larsen, Kasper Green

    2011-01-01

    and several natural special cases thereof. The rst special case is known as range median, which arises when k is xed to b(j 􀀀 i + 1)=2c. The second case, denoted prex selection, arises when i is xed to 0. Finally, we also consider the bounded rank prex selection problem and the xed rank range......Range selection is the problem of preprocessing an input array A of n unique integers, such that given a query (i; j; k), one can report the k'th smallest integer in the subarray A[i];A[i+1]; : : : ;A[j]. In this paper we consider static data structures in the word-RAM for range selection...... selection problem. In the former, data structures must support prex selection queries under the assumption that k for some value n given at construction time, while in the latter, data structures must support range selection queries where k is xed beforehand for all queries. We prove cell probe lower bounds...

  9. Substring Range Reporting

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2011-01-01

    We revisit various string indexing problems with range reporting features, namely, position-restricted substring searching, indexing substrings with gaps, and indexing substrings with intervals. We obtain the following main results. – We give efficient reductions for each of the above problems...... to a new problem, which we call substring range reporting. Hence, we unify the previous work by showing that we may restrict our attention to a single problem rather than studying each of the above problems individually. – We show how to solve substring range reporting with optimal query time and little...... space. Combined with our reductions this leads to significantly improved time-space trade-offs for the above problems. In particular, for each problem we obtain the first solutions with optimal time query and O(n logO(1) n) space, where n is the length of the indexed string. Our bounds for substring...

  10. Substring Range Reporting

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2014-01-01

    We revisit various string indexing problems with range reporting features, namely, position-restricted substring searching, indexing substrings with gaps, and indexing substrings with intervals. We obtain the following main results. We give efficient reductions for each of the above problems...... to a new problem, which we call substring range reporting. Hence, we unify the previous work by showing that we may restrict our attention to a single problem rather than studying each of the above problems individually. We show how to solve substring range reporting with optimal query time and little...... space. Combined with our reductions this leads to significantly improved time-space trade-offs for the above problems. In particular, for each problem we obtain the first solutions with optimal time query and O(nlog O(1) n) space, where n is the length of the indexed string. We show that our techniques...

  11. High resolution crustal structure for the region between the Chilenia and Cuyania terrane above the Pampean flat slab of Argentina from local receiver function and petrological analyses

    Science.gov (United States)

    Ammirati, J. B.; Alvarado, P. M.; Pérez, S. B.; Beck, S. L.; Porter, R. C.; Zandt, G.

    2015-12-01

    Jean-Baptiste Ammirati 1,Sofía Perez 1, Patricia Alvarado 1, Susan L. Beck 2, Ryan Porter 3 and George Zandt 2(1) CIGEOBIO-CONICET, Universidad Nacional de San Juan, Argentina (2) The University of Arizona, USA (3) Northern Arizona University, USA At ~31ºS, The subduction of the Nazca plate under the South American plate presents along-strike variations of its dip angle referred to the Chilean-Pampean flat slab. Geological observations suggest that the regional crustal structure is inherited from the accretion of different terranes at Ordovician times and later reactivated during Andean compression since Miocene. Geophysical observations confirmed that the structure is extending in depth with décollement levels that accommodate crustal shortening in the region. In order to get a better insight on the shallow tectonics we computed high frequency local receiver functions from slab seismicity (~100 km depth). Local earthquakes present a higher frequency content that permits a better vertical resolution. Using a common conversion point (CCP) stacking method we obtained cross sections showing high-resolution crustal structure in the western part of the Pampean flat slab region, at the transition between the Precordillera and the Frontal Cordillera. Our results show a well-defined structure and their lateral extent for both units down to 80 km depth. In good agreement with previous studies, our higher resolution images better identify very shallow discontinuities putting more constraints on the relationships with the regional structural geology. Recent petrological analyses combined with RF high-resolution structure also allow us to better understand the regional crustal composition. Interestingly, we are able to observe a shifting structure beneath the Uspallata-Calingasta Valley, highlighting the differences in terms of crustal structure between the Precordillera and the Frontal Cordillera. Previously determined focal mechanisms in the region match well this

  12. U-Pb SHRIMP zircon dating of high-grade rocks from the Upper Allochthonous Terrane of Bragança and Morais Massifs (NE Portugal); geodynamic consequences

    Science.gov (United States)

    Mateus, A.; Munhá, J.; Ribeiro, A.; Tassinari, C. C. G.; Sato, K.; Pereira, E.; Santos, J. F.

    2016-04-01

    Bragança and Morais Massifs are part of the mega-klippen ensemble of NW Iberia, comprising a tectonic pile of four allochthonous units stacked above the Central-Iberian Zone autochthon. On top of this pile, the Upper Allochthonous Terrane (UAT) includes different high-grade metamorphic series whose age and geodynamic meaning are controversial. Mafic granulites provided U-Pb zircon ages at 399 ± 7 Ma, dating the Variscan emplacement of UAT. In contrast, U-Pb zircon ages of ky- and hb-eclogites, felsic/intermediate HP/HT-granulites and orthogneisses (ca. 500-480 Ma) are identical to those of gabbros (488 ± 10 Ma) and Grt-pyroxenites (495 ± 8 Ma) belonging to a mafic/ultramafic igneous suite that records upper mantle melting and mafic magma crustal underplating at these times. Gabbros intrude the high-grade units of UAT and did not underwent the HP metamorphic event experienced by eclogites and granulites. These features and the zircon dates resemblance among different lithologies, suggest that extensive age resetting of older events may have been correlative with the igneous suite emplacement/crystallisation. Accordingly, reconciliation of structural, petrological and geochronological evidence implies that the development and early deformation of UAT high-grade rocks should be ascribed to an orogenic cycle prior to ≈ 500 Ma. Undisputable dating of this cycle is impossible, but the sporadic vestiges of Cadomian ages cannot be disregarded. The ca. 500-480 Ma time-window harmonises well with the Lower Palaeozoic continental rifting that trace the Variscan Wilson Cycle onset and the Rheic Ocean opening. Subsequent preservation of the high heat-flow regime, possibly related to the Palaeotethys back-arc basin development (ca. 450-420 Ma), would explain the 461 ± 10 Ma age yielded by some zircon domains in felsic granulites, conceivably reflecting zircon dissolution/recrystallisation till Ordovician times, long before the Variscan paroxysm (ca. 400-390 Ma). This

  13. Range-clustering queries

    DEFF Research Database (Denmark)

    Abrahamsen, Mikkel; de Berg, Mark; Buchin, Kevin

    2017-01-01

    an optimal k-clustering for S P ∩ Q. We obtain the following results. • We present a general method to compute a (1 + ϵ)-approximation to a range-clustering query, where ϵ > 0 is a parameter that can be specified as part of the query. Our method applies to a large class of clustering problems, including k...

  14. Agriculture, forestry, range resources

    Science.gov (United States)

    Macdonald, R. B.

    1974-01-01

    The necessary elements to perform global inventories of agriculture, forestry, and range resources are being brought together through the use of satellites, sensors, computers, mathematics, and phenomenology. Results of ERTS-1 applications in these areas, as well as soil mapping, are described.

  15. Space-Based Range

    Science.gov (United States)

    2008-01-01

    Space-Based Range (SBR), previously known as Space-Based Telemetry and Range Safety (STARS), is a multicenter NASA proof-of-concept project to determine if space-based communications using NASA's Tracking and Data Relay Satellite System (TDRSS) can support the Range Safety functions of acquiring tracking data and generating flight termination signals, while also providing broadband Range User data such as voice, video, and vehicle/payload data. There was a successful test of the Range Safety system at Wallops Flight Facility (WFF) on December 20, 2005, on a two-stage Terrier-Orion spin-stabilized sounding rocket. SBR transmitted GPS tracking data and maintained links with two TDRSS satellites simultaneously during the 10-min flight. The payload section deployed a parachute, landed in the Atlantic Ocean about 90 miles downrange from the launch site, and was successfully recovered. During the Terrier-Orion tests flights, more than 99 percent of all forward commands and more than 95 percent of all return frames were successfully received and processed. The time latency necessary for a command to travel from WFF over landlines to White Sands Complex and then to the vehicle via TDRSS, be processed onboard, and then be sent back to WFF was between 1.0 s and 1.1 s. The forward-link margins for TDRS-10 (TDRS East [TDE]) were 11 dB to 12 dB plus or minus 2 dB, and for TDRS-4 (TDRS Spare [TDS]) were 9 dB to 10 dB plus or minus 1.5 dB. The return-link margins for both TDE and TDS were 6 dB to 8 dB plus or minus 3 dB. There were 11 flights on an F-15B at Dryden Flight Research Center (DFRC) between November 2006 and February 2007. The Range User system tested a 184-element TDRSS Ku-band (15 GHz) phased-array antenna with data rates of 5 Mbps and 10 Mbps. This data was a combination of black-and-white cockpit video, Range Safety tracking and transceiver data, and aircraft and antenna controller data streams. IP data formatting was used.

  16. Range Flight Safety Requirements

    Science.gov (United States)

    Loftin, Charles E.; Hudson, Sandra M.

    2018-01-01

    The purpose of this NASA Technical Standard is to provide the technical requirements for the NPR 8715.5, Range Flight Safety Program, in regards to protection of the public, the NASA workforce, and property as it pertains to risk analysis, Flight Safety Systems (FSS), and range flight operations. This standard is approved for use by NASA Headquarters and NASA Centers, including Component Facilities and Technical and Service Support Centers, and may be cited in contract, program, and other Agency documents as a technical requirement. This standard may also apply to the Jet Propulsion Laboratory or to other contractors, grant recipients, or parties to agreements to the extent specified or referenced in their contracts, grants, or agreements, when these organizations conduct or participate in missions that involve range flight operations as defined by NPR 8715.5.1.2.2 In this standard, all mandatory actions (i.e., requirements) are denoted by statements containing the term “shall.”1.3 TailoringTailoring of this standard for application to a specific program or project shall be formally documented as part of program or project requirements and approved by the responsible Technical Authority in accordance with NPR 8715.3, NASA General Safety Program Requirements.

  17. Origin of the mafic microgranular enclaves (MMEs) and their host granitoids from the Tagong pluton in Songpan-Ganze terrane: An igneous response to the closure of the Paleo-Tethys ocean

    Science.gov (United States)

    Chen, Qiong; Sun, Min; Zhao, Guochun; Yang, Fengli; Long, Xiaoping; Li, Jianhua; Wang, Jun; Yu, Yang

    2017-10-01

    The Songpan-Ganze terrane is mainly composed of a Triassic sedimentary sequence and late Triassic-Jurassic igneous rocks. A large number of plutons were emplaced as a result of tectono-magmatic activity related to the late stages of Paleo-Tethys ocean closure and ensuing collision. Granitoids and their hosted mafic enclaves can provide important constraints on the crust-mantle interaction and continental crustal growth. Mesozoic magmatism of Songpan-Ganze remains enigmatic with regard to their magma generation and geodynamic evolution. The Tagong pluton (209 Ma), in the eastern part of the Songpan-Ganze terrane, consists mainly of monzogranite and granodiorite with abundant coeval mafic microgranular enclaves (MMEs) (ca. 208-209 Ma). The pluton comprises I-type granitoid that possesses intermediate to acidic compositions (SiO2 = 61.6-65.8 wt.%), high potassium (K2O = 3.2-4.1 wt.%), and high Mg# (51-54). They are also characterized by arc-type enrichment of LREEs and LILEs, depletion of HFSEs (e.g. Nb, Ta, Ti) and moderate Eu depletions (Eu/Eu* = 0.46-0.63). Their evolved zircon Hf and whole-rock Nd isotopic compositions indicate that their precursor magmas were likely generated by melting of old lower continental crust. Comparatively, the MMEs have lower SiO2 (53.4-58.2 wt.%), higher Mg# (54-67) and show covariation of major and trace elements, coupled with field and petrographic observations, such as the disequilibrium textures of plagioclase and amphibole, indicating that the MMEs and host granitoids were originated from different magma sources but underwent mafic-felsic magma mixing process. Geochemical and isotopic data further suggest that the precursor magma of the MMEs was formed in the continental arc setting, mainly derived from an ancient metasomatized lithospheric mantle wedge. The Triassic granitoids from the Songpan-Ganze terrane show remarkable temporal-spatial-petrogenetic affinities to the counterparts of subduction zones in the Yidun and Kunlun arc

  18. Resetting of Neoarchaean hornblendes from the Murmansk Terrane (Kola Peninsula, Russia) revealed by a combined 40Ar/39Ar and Rb-Sr analysis

    Science.gov (United States)

    de Jong, K.; Timmerman, M. J.; Cliff, R. A.; Wijbrans, J. R.; Daly, J. S.; Balagansky, V. V.

    2003-04-01

    We present isotope data from amphiboles from the 2.6--2.8 Ga Murmansk Terrane in the northern foreland of the 1.9 Ga Lapland-Kola Orogen of northern Fennoscandia. Most amphiboles are zoned with tschermakitic cores that progressively change to actinolite in 5--10 μm wide areas in rims, defect zones or adjacent to biotite. Biotite chiefly occurs along cleavages, fractures and grain boundaries of amphibole, showing that its hydration and fluid ingress are confined to lattice imperfections. Furnace step heating of hornblende separate MT-11 gave spectra with increasing apparent ages and Ca/K ratios (a proxy for 37ArCa/39Ar_K). Hornblende is intergrown with biotite that also occurs in the matrix. Yet, laser step heating of single hornblende grain MT-11 yielded flat spectra with Neoarchaean apparent ages and constant Ca/K ratios. This suggests that the hornblende grain that was drilled from a thin section and which was not affected by biotite growth retained its Neoarchaean age. In contrast, the hornblende separate with intergrown biotite from this sample has a partially reset Neoarchaean isotope system. Hornblende MT-27 has Neoarchaean apparent ages and lacks low Ca/K ratios in both single grain and mineral separate spectra; it is not affected by biotite growth and this mineral is also absent from the matrix. Age spectra of other hornblende separates have increasing apparent ages to 2.56--2.65 Ga during final 39Ar release; their Ca/K ratio spectra similarly increase. Low Ca/K ratios for gas release below 950^oC imply degassing of included biotite. Apparent ages of the first heating increments may be as young as 1.8 Ga, comparable to the K-Ar and 40Ar/39Ar ages of the youngest biotites. Hornblende-plagioclase pairs from aliquots used for 40Ar/39Ar furnace step heating yielded sharply discordant Rb-Sr ages. MT-11 yielded an 1881 ± 23 Ma Rb-Sr age that compares well with the K-Ar and 40Ar/39Ar ages of biotite in the sample. In contrast, hornblende of sample MT-27 has a

  19. Survival of the Lhasa Terrane during its collision with Asia due to crust-mantle coupling revealed by ca. 114 Ma intrusive rocks in western Tibet

    Science.gov (United States)

    Wang, Qing; Zhu, Di-Cheng; Liu, An-Lin; Cawood, Peter A.; Liu, Sheng-Ao; Xia, Ying; Chen, Yue; Wang, Hao; Zhang, Liang-Liang; Zhao, Zhi-Dan

    2018-04-01

    Survival of the Lhasa Terrane during its drift across the Tethyan Ocean and subsequent collision with Asia was likely maintained by mechanical coupling between its ancient lithospheric mantle and the overlying crust. Evidence for this coupling is provided by geochronological and geochemical data from high-Mg dioritic porphyrite dikes that intruded into granodiorites with dioritic enclaves within the Nixiong Batholith in the western segment of the central Lhasa subterrane, southern Tibet. Zircon LA-ICP-MS U-Pb dating indicates synchronous emplacement of dioritic porphyrite dikes (113.9 ± 2 Ma), dioritic enclaves (113.9 ± 1 Ma), and host granodiorites (113.1 ± 2 Ma). The hornblende-bearing granodiorites are metaluminous to weakly peraluminous (A/CNK = 0.95-1.05) and belong to high-K calc-alkaline I-type granite. These rocks are characterized by low Mg# (37-43), negative zircon εHf(t) values (-6.8 to -1.2), and negative whole-rock εNd(t) values (-8.1 to -5.4), suggestive of derivation through anatexis of ancient lower crust. The two least-mixed or contaminated dioritic porphyrite dike samples have high MgO (8.46-8.74 wt%), high Mg# (69-70), and high abundances of compatible elements (e.g., Cr = 673-646 ppm, Ni = 177-189 ppm), which are close to those of primitive magma. They are high-K calc-alkaline and show negative whole-rock εNd(t) values (-1.9 to -1.2), indicating that these samples are most likely derived from the partial melting of ancient lithospheric mantle that was metasomatized by slab-derived fluids. The dioritic enclave samples are metaluminous high-K calc-alkaline and have varying negative whole-rock εNd(t) values (-7.8 to -3.7), which are interpreted as the result of magma mixing between the ancient lower crust-derived melts and asthenospheric mantle- (rather than lithospheric mantle-) derived melts. The Nd isotope mantle model ages of the least-mixed or contaminated high-Mg dioritic porphyrite dike samples (1.1-1.4 Ga) are close to the Nd isotope

  20. Ecosystem health in mineralized terrane; data from podiform chromite (Chinese Camp mining district, California), quartz alunite (Castle Peak and Masonic mining districts, Nevada/California), and Mo/Cu porphyry (Battle Mountain mining district, Nevada) deposits

    Science.gov (United States)

    Blecker, Steve W.; Stillings, Lisa L.; Amacher, Michael C.; Ippolito, James A.; DeCrappeo, Nicole M.

    2010-01-01

    within various mineralized terranes. We were also interested in examining these relations in the context of determining appropriate reference conditions with which to compare reclamation efforts.The purpose of this report is to present the data used to develop indices of soil and ecosystem quality associated with mineralized terranes (areas enriched in metal-bearing minerals), specifically podiform chromite, quartz alunite, and Mo/Cu porphyry systems. Within each of these mineralized terranes, a nearby unmineralized counterpart was chosen for comparison. The data consist of soil biological, chemical, and physical parameters, along with vegetation measurements for each of the sites described below. Synthesis of these data and index development will be the subject of future publications.

  1. Neutron range spectrometer

    Science.gov (United States)

    Manglos, Stephen H.

    1989-06-06

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

  2. Geochemistry, petrography, and zircon U-Pb geochronology of Paleozoic metaigneous rocks in the Mount Veta area of east-central Alaska: implications for the evolution of the westernmost part of the Yukon-Tanana terrane

    Science.gov (United States)

    Dusel-Bacon, Cynthia; Day, Warren C.; Aleinikoff, John N.

    2013-01-01

    We report the results of new mapping, whole-rock major, minor, and trace-element geochemistry, and petrography for metaigneous rocks from the Mount Veta area in the westernmost part of the allochthonous Yukon–Tanana terrane (YTT) in east-central Alaska. These rocks include tonalitic mylonite gneiss and mafic metaigneous rocks from the Chicken metamorphic complex and the Nasina and Fortymile River assemblages. Whole-rock trace-element data from the tonalitic gneiss, whose igneous protolith was dated by SHRIMP U–Pb zircon geochronology at 332.6 ± 5.6 Ma, indicate derivation from tholeiitic arc basalt. Whole-rock analyses of the mafic rocks suggest that greenschist-facies rocks from the Chicken metamorphic complex, a mafic metavolcanic rock from the Nasina assemblage, and an amphibolite from the Fortymile River assemblage formed as island-arc tholeiite in a back-arc setting; another Nasina assemblage greenschist has MORB geochemical characteristics, and another mafic metaigneous rock from the Fortymile River assemblage has geochemical characteristics of calc-alkaline basalt. Our geochemical results imply derivation in an arc and back-arc spreading region within the allochthonous YTT crustal fragment, as previously proposed for correlative units in other parts of the terrane. We also describe the petrography and geochemistry of a newly discovered tectonic lens of Alpine-type metaharzburgite. The metaharzburgite is interpreted to be a sliver of lithospheric mantle from beneath the Seventymile ocean basin or from sub-continental mantle lithosphere of the allochthonous YTT or the western margin of Laurentia that was tectonically emplaced within crustal rocks during closure of the Seventymile ocean basin and subsequently displaced and fragmented by faults.

  3. Flux and genesis of CO2 degassing from volcanic-geothermal fields of Gulu-Yadong rift in the Lhasa terrane, South Tibet: Constraints on characteristics of deep carbon cycle in the India-Asia continent subduction zone

    Science.gov (United States)

    Zhang, Lihong; Guo, Zhengfu; Sano, Yuji; Zhang, Maoliang; Sun, Yutao; Cheng, Zhihui; Yang, Tsanyao Frank

    2017-11-01

    Gulu-Yadong rift (GYR) is the longest extensional, NE-SW-trending rift in the Himalayas and Lhasa terrane of South Tibet. Many volcanic-geothermal fields (VGFs), which comprise intense hot springs, steaming fissures, geysers and soil micro-seepage, are distributed in the GYR, making it ideal area for studying deep carbon emissions in the India-Asia continent subduction zone. As for the northern segment of GYR in the Lhasa terrane, its total flux and genesis of CO2 emissions are poorly understood. Following accumulation chamber method, soil CO2 flux survey has been carried out in VGFs (i.e., Jidaguo, Ningzhong, Sanglai, Tuoma and Yuzhai from south to north) of the northern segment of GYR. Total soil CO2 output of the northern GYR is about 1.50 × 107 t a-1, which is attributed to biogenic and volcanic-geothermal source. Geochemical characteristics of the volcanic-geothermal gases (including CO2 and He) of the northern GYR indicate their significant mantle-derived affinities. Combined with previous petrogeochemical and geophysical data, our He-C isotope modeling calculation results show that (1) excess mantle-derived 3He reflects degassing of volatiles related with partial melts from enriched mantle wedge induced by northward subduction of the Indian lithosphere, and (2) the crust-mantle interaction can provide continuous heat and materials for the overlying volcanic-geothermal system, in which magma-derived volatiles are inferred to experience significant crustal contamination during their migration to the surface.

  4. Super-ranging. A new ranging strategy in European badgers.

    Directory of Open Access Journals (Sweden)

    Aoibheann Gaughran

    Full Text Available We monitored the ranging of a wild European badger (Meles meles population over 7 years using GPS tracking collars. Badger range sizes varied seasonally and reached their maximum in June, July and August. We analysed the summer ranging behaviour, using 83 home range estimates from 48 individuals over 6974 collar-nights. We found that while most adult badgers (males and females remained within their own traditional social group boundaries, several male badgers (on average 22% regularly ranged beyond these traditional boundaries. These adult males frequently ranged throughout two (or more social group's traditional territories and had extremely large home ranges. We therefore refer to them as super-rangers. While ranging across traditional boundaries has been recorded over short periods of time for extraterritorial mating and foraging forays, or for pre-dispersal exploration, the animals in this study maintained their super-ranges from 2 to 36 months. This study represents the first time such long-term extra-territorial ranging has been described for European badgers. Holding a super-range may confer an advantage in access to breeding females, but could also affect local interaction networks. In Ireland & the UK, badgers act as a wildlife reservoir for bovine tuberculosis (TB. Super-ranging may facilitate the spread of disease by increasing both direct interactions between conspecifics, particularly across social groups, and indirect interactions with cattle in their shared environment. Understanding super-ranging behaviour may both improve our understanding of tuberculosis epidemiology and inform future control strategies.

  5. Rock glaciers, Zailiysiky Range, Kungei Ranges, Tienshan, Kazakhstan, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Zailiyskiy Alatau is the northernmost parallel latitudinal ranges of the Northern Tien Shan. The highest point of this range is the Talgar peak (4973 m a.s.l.)....

  6. A comparison of geochemical exploration techniques and sample media within accretionary continental margins: an example from the Pacific Border Ranges, Southern Alaska, U.S.A.

    Science.gov (United States)

    Sutley, S.J.; Goldfarb, R.J.; O'Leary, R. M.; Tripp, R.B.

    1990-01-01

    The Pacific Border Ranges of the southern Alaskan Cordillera are composed of a number of allochthonous tectonostratigraphic terranes. Within these terranes are widespread volcanogenic, massive sulfide deposits in and adjacent to portions of accreted ophiolite complexes, bands and disseminations of chromite in accreted island-arc ultramafic rocks, and epigenetic, gold-bearing quartz veins in metamorphosed turbidite sequences. A geochemical pilot study was undertaken to determine the most efficient exploration strategy for locating these types of mineral deposits within the Pacific Border Ranges and other typical convergent continental margin environments. High-density sediment sampling was carried out in first- and second-order stream channels surrounding typical gold, chromite and massive sulfide occurrences. At each site, a stream-sediment and a panned-concentrate sample were collected. In the laboratory, the stream sediments were sieved into coarse-sand, fine- to medium-sand, and silt- to clay-size fractions prior to analysis. One split of the panned concentrates was retained for analysis; a second split was further concentrated by gravity separation in heavy liquids and then divided into magnetic, weakly magnetic and nonmagnetic fractions for analysis. A number of different techniques including atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry and semi-quantitative emission spectrography were used to analyze the various sample media. Comparison of the various types of sample media shows that in this tectonic environment it is most efficient to include a silt- to clay-size sediment fraction and a panned-concentrate sample. Even with the relatively low detection limits for many elements by plasma spectrometry and atomic absorption spectrometry, anomalies reflecting the presence of gold veins could not be identified in any of the stream-sediment fractions. Unseparated panned-concentrate samples should be analyzed by emission

  7. Lost Terranes of Zealandia: possible development of late Paleozoic and early Mesozoic sedimentary basins at the southwest Pacific margin of Gondwanaland, and their destination as terranes in southern South America Terrenos perdidos de Zealandia: posible desarrollo de cuencas sedimentarias del Paleozoico tardío y Mesozoico temprano en el margen suroccidental del Pacífico de Gondwana y su destino como terrenos en el sur de América del Sur

    Directory of Open Access Journals (Sweden)

    Christopher J Adams

    2010-07-01

    Full Text Available Latest Precambrian to Ordovician metasedimentary successions and Cambrian-Ordovician and Devonian-Carboniferous granitoids form the major part of the basement of southern Zealandia and adjacent sectors of Antarctica and southeast Australia. Uplift/cooling ages of these rocks, and local Devonian shallow-water cover sequences suggest that final consolidation of the basement occurred through Late Paleozoic time. A necessary consequence of this process would have been contemporaneous erosion and the substantial development of marine sedimentary basins at the Pacific margin of Zealandia. These are found nowhere at the present day, suggesting that the basins have been lost by tectonic erosion, perhaps in a margin-parallel dextral translation similar to late Paleozoic-Mesozoic suspect terranes of New Zealand. Aprobable detrital zircon age pattern is assembled for these lost Zealandia sediments, and then compared with those of pre-Jurassic (probable Triassic to Devonian metasedimentary rocks in the Chilean archipelago. Significant Mesoproterozoic, latest Neoproterozoic-Cambrian and Devonian-Carboniferous detrital zircon age components are common to both, thus supporting a possible Chilean terrane destination for these 'lost terranes of Zealandia'.Las sucesiones metasedimentarias del Precámbrico tardío al Ordovícico y granitoides del Cámbrico-Ordovícico y Devónico-Carbonífero constituyen la mayor parte del basamento del sur de Zealandia y sectores adyacentes de la Antartica y el sudeste de Australia. Las edades de enfriamiento/alzamiento de estas rocas y la cobertura local de secuencias de aguas someras del Devónico, sugieren que la consolidación definitiva del basamento se produjo durante el Paleozoico tardío. Una consecuencia necesaria de este proceso habría sido la erosion contemporánea y el desarrollo sustancial de cuencas sedimentarias marinas en el margen del Pacífico de Zealandia. Estas no se encuentran en ninguna parte en la

  8. Cascade Mountain Range in Oregon

    Science.gov (United States)

    Sherrod, David R.

    2016-01-01

    The Cascade mountain system extends from northern California to central British Columbia. In Oregon, it comprises the Cascade Range, which is 260 miles long and, at greatest breadth, 90 miles wide (fig. 1). Oregon’s Cascade Range covers roughly 17,000 square miles, or about 17 percent of the state, an area larger than each of the smallest nine of the fifty United States. The range is bounded on the east by U.S. Highways 97 and 197. On the west it reaches nearly to Interstate 5, forming the eastern margin of the Willamette Valley and, farther south, abutting the Coast Ranges

  9. Osprey Range - CWHR [ds601

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  10. Precise Range Determination Using Laser Ranging Data of LAGEOS

    Directory of Open Access Journals (Sweden)

    Kwang-Ryul Kim

    1993-12-01

    Full Text Available Satellite laser ranging observation of LAGEOS ¥± has been performed using the SLR System at Sheshan Laser Ranging Station, Shanghai Observatory. And we obtained 1,838 observational points The observed range data is corrected by means of system delay correction using ground target observation, atmospheric refraction delay correction, offset correction, general relativistic correction and tide correction including solid tide, polar tide and ocean tide. As a result, the determined range delay mean value is 19.12m and the mean internal accuracy by means of polynomial fitting and least square method is ¡¾7cm. Corrected observational points are 1,340 and noise ratio to total observational points is 27.1%

  11. Foraging optimally for home ranges

    Science.gov (United States)

    Mitchell, Michael S.; Powell, Roger A.

    2012-01-01

    Economic models predict behavior of animals based on the presumption that natural selection has shaped behaviors important to an animal's fitness to maximize benefits over costs. Economic analyses have shown that territories of animals are structured by trade-offs between benefits gained from resources and costs of defending them. Intuitively, home ranges should be similarly structured, but trade-offs are difficult to assess because there are no costs of defense, thus economic models of home-range behavior are rare. We present economic models that predict how home ranges can be efficient with respect to spatially distributed resources, discounted for travel costs, under 2 strategies of optimization, resource maximization and area minimization. We show how constraints such as competitors can influence structure of homes ranges through resource depression, ultimately structuring density of animals within a population and their distribution on a landscape. We present simulations based on these models to show how they can be generally predictive of home-range behavior and the mechanisms that structure the spatial distribution of animals. We also show how contiguous home ranges estimated statistically from location data can be misleading for animals that optimize home ranges on landscapes with patchily distributed resources. We conclude with a summary of how we applied our models to nonterritorial black bears (Ursus americanus) living in the mountains of North Carolina, where we found their home ranges were best predicted by an area-minimization strategy constrained by intraspecific competition within a social hierarchy. Economic models can provide strong inference about home-range behavior and the resources that structure home ranges by offering falsifiable, a priori hypotheses that can be tested with field observations.

  12. GPS test range mission planning

    Science.gov (United States)

    Roberts, Iris P.; Hancock, Thomas P.

    The principal features of the Test Range User Mission Planner (TRUMP), a PC-resident tool designed to aid in deploying and utilizing GPS-based test range assets, are reviewed. TRUMP features time history plots of time-space-position information (TSPI); performance based on a dynamic GPS/inertial system simulation; time history plots of TSPI data link connectivity; digital terrain elevation data maps with user-defined cultural features; and two-dimensional coverage plots of ground-based test range assets. Some functions to be added during the next development phase are discussed.

  13. Genus Ranges of Chord Diagrams.

    Science.gov (United States)

    Burns, Jonathan; Jonoska, Nataša; Saito, Masahico

    2015-04-01

    A chord diagram consists of a circle, called the backbone, with line segments, called chords, whose endpoints are attached to distinct points on the circle. The genus of a chord diagram is the genus of the orientable surface obtained by thickening the backbone to an annulus and attaching bands to the inner boundary circle at the ends of each chord. Variations of this construction are considered here, where bands are possibly attached to the outer boundary circle of the annulus. The genus range of a chord diagram is the genus values over all such variations of surfaces thus obtained from a given chord diagram. Genus ranges of chord diagrams for a fixed number of chords are studied. Integer intervals that can be, and those that cannot be, realized as genus ranges are investigated. Computer calculations are presented, and play a key role in discovering and proving the properties of genus ranges.

  14. Late Mesozoic basin and range tectonics and related magmatism in Southeast China

    Directory of Open Access Journals (Sweden)

    Dezi Wang

    2012-03-01

    Full Text Available During the Late Mesozoic Middle Jurassic–Late Cretaceous, basin and range tectonics and associated magmatism representative of an extensional tectonic setting was widespread in southeastern China as a result of Pacific Plate subduction. Basin tectonics consists of post-orogenic (Type I and intra-continental extensional basins (Type II. Type I basins developed in the piedmont and intraland during the Late Triassic to Early Jurassic, in which coarse-grained terrestrial clastic sediments were deposited. Type II basins formed during intra-continental crustal thinning and were characterized by the development of grabens and half-grabens. Graben basins were mainly generated during the Middle Jurassic and were associated with bimodal volcanism. Sediments in half-grabens are intercalated with rhyolitic tuffs and lavas and are Early Cretaceous in age with a dominance of Late Cretaceous–Paleogene red beds. Ranges are composed of granitoids and bimodal volcanic rocks, A-type granites and dome-type metamorphic core complexes. The authors analyzed lithological, geochemical and geochronological features of the Late Mesozoic igneous rock assemblages and proposed some geodynamical constraints on forming the basin and range tectonics of South China. A comparison of the similarities and differences of basin and range tectonics between the eastern and western shores of the Pacific is made, and the geodynamical evolution model of the Southeast China Block during Late Mesozoic is discussed. Studied results suggest that the basin and range terrane within South China developed on a pre-Mesozoic folded belt was derived from a polyphase tectonic evolution mainly constrained by subduction of the western Pacific Plate since the Late Mesozoic, leading to formation of various magmatism in a back-arc extensional setting. Its geodynamic mechanism can compare with that of basin and range tectonics in the eastern shore of the Pacific. Differences of basin and range

  15. Eye safe laser range finders

    International Nuclear Information System (INIS)

    Snir, M.; Margaliot, M.; Amitzi, A.

    2004-01-01

    During the 1970's, Ruby (Q switched) laser based range finders with a wavelength of 694nm were first used. These lasers operated in a pulse mode within the visible light range and produced a risk for the eye retina. The laser beam striking the macula could damage the eye and might cause blindness. Over the years, Nd:YAG (Q switched) lasers were developed (operating at 1064nm) for range finding and designation uses. The wavelength of these lasers, operating in the near Infra-Red range (invisible), is also focused tightly on the retina. The human eye does not respond to the invisible light so there is no natural protection (eye blink reflex) as in the visible light. The operation of these lasers worldwide, especially when the laser beam is exposed, causes occasional eye accidents. Another risk is stemming from the use of observation systems with a high optical gain, in the laser operation areas, which enlarge the range of risk quite significantly. Therefore, research and development efforts were invested in order to introduce eye safe lasers. One of the solutions for this problem is presented in following document

  16. High dynamic range ultrasound imaging.

    Science.gov (United States)

    Degirmenci, Alperen; Perrin, Douglas P; Howe, Robert D

    2018-03-16

    High dynamic range (HDR) imaging is a popular computational photography technique that has found its way into every modern smartphone and camera. In HDR imaging, images acquired at different exposures are combined to increase the luminance range of the final image, thereby extending the limited dynamic range of the camera. Ultrasound imaging suffers from limited dynamic range as well; at higher power levels, the hyperechogenic tissue is overexposed, whereas at lower power levels, hypoechogenic tissue details are not visible. In this work, we apply HDR techniques to ultrasound imaging, where we combine ultrasound images acquired at different power levels to improve the level of detail visible in the final image. Ultrasound images of ex vivo and in vivo tissue are acquired at different acoustic power levels and then combined to generate HDR ultrasound (HDR-US) images. The performance of five tone mapping operators is quantitatively evaluated using a similarity metric to determine the most suitable mapping for HDR-US imaging. The ex vivo and in vivo results demonstrated that HDR-US imaging enables visualizing both hyper- and hypoechogenic tissue at once in a single image. The Durand tone mapping operator preserved the most amount of detail across the dynamic range. Our results strongly suggest that HDR-US imaging can improve the utility of ultrasound in image-based diagnosis and procedure guidance.

  17. Wide Operational Range Thermal Sensor

    Science.gov (United States)

    Goebel, John H. (Inventor); McMurray, Robert E., Jr. (Inventor)

    2005-01-01

    Bolometer system and method for detecting, at BLIP levels, presence of radiation over a broad range of wavelengths in an infrared spectrum and in a temperature range from 20 K to as high as room temperature. The radiation is received by a Si crystal having a region that is doped with one or more of In, Ga, S, Se, Te, B, Al, P, As and Sb in a concentration ratio in a range such as 5 x 10(exp -11) to 5 x 10(exp -6). Change in electrical resistance delta R due to receipt of the radiation is measured through a change in voltage difference or current within the crystal, and the quantity delta R is converted to an estimate of the amount of radiation received. Optionally, incident radiation having an energy high enough to promote photoconductivity is removed before detection.

  18. Radio pill antenna range test

    Science.gov (United States)

    Cummins, W. F.; Kane, R. J.

    1992-05-01

    In order to investigate the potential of a proposed 'radio pill' beacon transmitter, a range test experiment was devised and carried out in the VHF frequency range. Calculations and previous work indicated that optimum sensitivity and, thus, distance would be obtained in this frequency range provided body radio-frequency (RF) absorption was not too great. A ferrite-core loop antenna is compatible with a pill geometry and has better radiation efficiency than an air core loop. The ferrite core may be a hollow cylinder with the electronics and batteries placed inside. However, this range test was only concerned with experimentally developing test range data on the ferrite core antenna itself. A one turn strap loop was placed around a 9.5 mm diameter by 18.3 mm long stack of ferrite cores. This was coupled to a 50 Omega transmission line by 76 mm of twisted pair line and a capacitive matching section. This assembly was excited by a signal generator at output levels of -10 to +10 dBm. Signals were received on a VHF receiver and tape recorder coupled to a 14 element, circularly polarized Yagi antenna at a height of 2.5 m. Field strength measurements taken at ranges of 440, 1100, and 1714 m. Maximum field strengths referenced to 0 dBm transmitter level were -107 to -110 dB at 440 m, -124 to -127 dBm at 1100 m, and -116 to -119 dBm at 1714 m when the antenna cylinder was horizontal. Field strengths with a vertical antenna were about 6 dB below these values. The latter transmit site was elevated and had a clear line-of-site path to the receiving site. The performance of this test antenna was better than that expected from method-of-moment field calculations. When this performance data is scaled to a narrow bandwidth receiving system, ground level receiving ranges of a few to 10 km can be expected. Clear line-of-sight ranges where either or both the transmitter and receiver are elevated could vary from several km to 100 km.

  19. GEA CRDA Range Data Analysis

    Science.gov (United States)

    1999-07-28

    E1, July-August 1998 18 3.3. Example 3: SatMex, Solidaridad 2, May-June 1998 27 3.4. Example 4: PanAmSat, Galaxy IV, May-June 1998 33 3.5...17 Millstone measurements residuals for Telstar 401 on Days 181-263. 26 3-18 Millstone measurement residuals for Solidaridad 1 on Days 141-153...with 29 SatMex range data. 3-19 Hermosillo B-- Solidaridad 1 range residuals through Days 135-144 with bias 30 removed. 3-20 Iztapalapa D

  20. Geology, petrology, U-Pb (shrimp geochronology of the Morrinhos granite -Paraguá terrane, SW Amazonian craton: implications for the magmatic evolution of the San Ignácio orogeny

    Directory of Open Access Journals (Sweden)

    Ohana França

    Full Text Available Morrinhos granite is a batholith body that is slightly elongated in the NNW direction and approximately 1,140 km2 long; it is located in the municipality of Vila Bela da Santíssima Trindade of the state of Mato Grosso, Brazil, in the Paraguá Terrane, Rondonian-San Ignácio Province, in the SW portion of the Amazonian Craton. This intrusion displays a compositional variation from tonalite to monzogranite, has a medium to coarse inequigranular texture and is locally porphyritic; biotite is the predominant mafic in one of the facies, and hornblende is predominant in the other, with both metamorphosed into the greenschist facies. The studied rocks characterize an intermediate to acidic sequence that was formed by a subalkaline magmatism; the series is alkali-calcic to metaluminous to slightly peraluminous, and the rocks evolved through fractioned crystallization mechanisms. The structural data show two deformation phases represented by penetrative foliation (S1 and open folds (D2, and both phases were most likely related to the San Ignácio Orogeny. The geochronological (U-Pb SHRIMP and isotopic (Sm-Nd investigations of these rocks indicated a crystallization age of 1350 ± 12 Ma, TDMof approximately 1.77 Ga and εNd(1.35with a negative value of -2.57, suggesting that their generation was related to a partial melting process of a Paleoproterozoic (Statherian continental crust. The results herein indicate that the Morrinhos granite was generated in a continental magmatic arc in a late- to post-orogenic stage of the San Ignácio Orogeny, and it can be recognized as belonging to the Pensamiento Intrusive Suite.

  1. Evolution of the Archean continental crust in the nucleus of the Yangtze block: Evidence from geochemistry of 3.0 Ga TTG gneisses in the Kongling high-grade metamorphic terrane, South China

    Science.gov (United States)

    Qiu, Xiao-Fei; Ling, Wen-Li; Liu, Xiao-Ming; Lu, Shan-Song; Jiang, Tuo; Wei, Yun-Xu; Peng, Lian-Hong; Tan, Juan-Juan

    2018-04-01

    Archean Tonalite-Trondhjemite-Granodiorite (TTG) rocks are scattered within the Kongling high-grade metamorphic terrane (KHMT) in the northern South China block. A comprehensive geochronological and geochemical study is carried out on the Taoyuan granitic gneisses, a newly recognized TTG suite in the northwestern KHMT. This suite has long been regarded as a Mesoproterozoic magmatic pluton, but U-Pb zircon ages of 2994 ± 22 Ma and 2970 ± 15 Ma are obtained by LA-ICP-MS method in this study. The Taoyuan gneiss suite is trondhjemitic in composition, and has high SiO2 (67.80-74.93 wt.%), Na2O (5.11-5.81 wt.%) contents with Na2O/K2O ratios greater than unity, and low Ni (2.56-7.61 ppm), Cr (1.26-7.67 ppm), Yb (0.32-0.82 ppm) and Y (4.48-11.5 ppm) contents. Plots show large variation in La/Yb and Sr/Y ratios and pronounced depletion in Nb, Ta and Ti in the primitive mantle-normalized spiderdiagram. The gneiss suite also displays two-stage Nd model ages close to its crystallization age with corresponding εNd(t) values of -2.5 to +3.5. It is thus suggested that the Taoyuan gneisses, in fact, is part of the Archean Kongling basement complex. Geochemical evidence implies that the TTG rocks may be derived from partial melting of subducted oceanic crust from a garnetiferous amphibolite source with residual assemblage of garnet + amphibole + plagioclase. Our study further indicates that the nucleus of the Yangtze block might experience a juvenile continental crustal growth during Mesoarchean. We also suggest that the Yangtze block may have its own crustal evolutionary history independent from the North China craton and the Tarim block before Paleoproterozoic.

  2. Dynamic range majority data structures

    DEFF Research Database (Denmark)

    Elmasry, Amr Ahmed Abd Elmoneim; He, Meng; Munro, J. Ian

    2011-01-01

    Given a set P of n coloured points on the real line, we study the problem of answering range α-majority (or "heavy hitter") queries on P. More specifically, for a query range Q, we want to return each colour that is assigned to more than an α-fraction of the points contained in Q. We present a new......((lg n/(α lglg n)). For constant values of α, this improved query time matches an existing lower bound, for any data structure with polylogarithmic update time. We also generalize our data structure to handle sets of points in d-dimensions, for d ≥ 2, as well as dynamic arrays, in which each entry...

  3. Short-range communication system

    Science.gov (United States)

    Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2012-01-01

    A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

  4. Propagator for finite range potentials

    International Nuclear Information System (INIS)

    Cacciari, Ilaria; Moretti, Paolo

    2006-01-01

    The Schroedinger equation in integral form is applied to the one-dimensional scattering problem in the case of a general finite range, nonsingular potential. A simple expression for the Laplace transform of the transmission propagator is obtained in terms of the associated Fredholm determinant, by means of matrix methods; the particular form of the kernel and the peculiar aspects of the transmission problem play an important role. The application to an array of delta potentials is shown

  5. Long Range Aircraft Trajectory Prediction

    OpenAIRE

    Magister, Tone

    2009-01-01

    The subject of the paper is the improvement of the aircraft future trajectory prediction accuracy for long-range airborne separation assurance. The strategic planning of safe aircraft flights and effective conflict avoidance tactics demand timely and accurate conflict detection based upon future four–dimensional airborne traffic situation prediction which is as accurate as each aircraft flight trajectory prediction. The improved kinematics model of aircraft relative flight considering flight ...

  6. Long range supergravity coupling strengths

    International Nuclear Information System (INIS)

    Kenyon, I.R.

    1991-01-01

    A limit of 2x10 -13 has recently been deduced for the fractional difference between the gravitational masses of the K 0 and anti K 0 mesons. This limit is applied here to put stringent limits on the strengths of the long range vector-scalar gravitational couplings envisaged in supergravity theories. A weaker limit is inferred from the general relativistic fit to the precession of the orbit of the pulsar PSR1913+16. (orig.)

  7. The International Laser Ranging Service

    Science.gov (United States)

    Pearlman, Michael; Noll, Carey; McGarry, Jan; Gurtner, Werner; Pavlis, Erricos

    2009-03-01

    The International Laser Ranging Service (ILRS) was established in September 1998 as a service within the IAG to support programs in geodetic, geophysical, and lunar research activities and to provide data products to the International Earth Rotation and Reference Frame Service (IERS) in support of its prime objectives. The ILRS develops the standards and specifications necessary for product consistency and the priorities and tracking strategies required to maximize network efficiency. This network consists of more than 30 Satellite Laser Ranging (SLR) stations, routinely tracking nearly 30 retroreflector-equipped satellites and the Moon in support of user needs. The Service collects, merges, analyzes, archives, and distributes satellite and lunar laser ranging data to satisfy a variety of scientific, engineering, and operational needs and encourages the application of new technologies to enhance the quality, quantity, and cost effectiveness of its data products. The ILRS works with the global network to improve station performance, new satellite missions in the design and building of retroreflector targets to maximize data quality and quantity, and science programs to optimize scientific data yield. The ILRS Central Bureau maintains a comprehensive web site (http://ilrs.gsfc.nasa.gov) as the primary vehicle for the distribution of information within the ILRS community. During the last few years, the ILRS has addressed very important challenges. Several new SLR stations have enhanced the global coverage of the network, particularly in the Southern Hemisphere. Two Combination Centers have been established to provide Official ILRS Data Products to the IERS for the process of maintaining the ITRF (International Terrestrial Reference Frame), and seven ILRS Analysis Centers have been established to provide the solutions for the combination process. Procedures have been introduced to track vulnerable satellites, such as ICESat and ALOS. Work continues at several

  8. Range gated strip proximity sensor

    Science.gov (United States)

    McEwan, T.E.

    1996-12-03

    A range gated strip proximity sensor uses one set of sensor electronics and a distributed antenna or strip which extends along the perimeter to be sensed. A micro-power RF transmitter is coupled to the first end of the strip and transmits a sequence of RF pulses on the strip to produce a sensor field along the strip. A receiver is coupled to the second end of the strip, and generates a field reference signal in response to the sequence of pulse on the line combined with received electromagnetic energy from reflections in the field. The sensor signals comprise pulses of radio frequency signals having a duration of less than 10 nanoseconds, and a pulse repetition rate on the order of 1 to 10 MegaHertz or less. The duration of the radio frequency pulses is adjusted to control the range of the sensor. An RF detector feeds a filter capacitor in response to received pulses on the strip line to produce a field reference signal representing the average amplitude of the received pulses. When a received pulse is mixed with a received echo, the mixing causes a fluctuation in the amplitude of the field reference signal, providing a range-limited Doppler type signature of a field disturbance. 6 figs.

  9. Medium Range Forecasts Representation (and Long Range Forecasts?)

    Science.gov (United States)

    Vincendon, J.-C.

    2009-09-01

    The progress of the numerical forecasts urges us to interest us in more and more distant ranges. We thus supply more and more forecasts with term of some days. Nevertheless, precautions of use are necessary to give the most reliable and the most relevant possible information. Available in a TV bulletin or on quite other support (Internet, mobile phone), the interpretation and the representation of a medium range forecast (5 - 15 days) must be different from those of a short range forecast. Indeed, the "foresee-ability” of a meteorological phenomenon decreases gradually in the course of the ranges, it decreases all the more quickly that the phenomenon is of small scale. So, at the end of some days, the probability character of a forecast becomes very widely dominating. That is why in Meteo-France the forecasts of D+4 to D+7 are accompanied with a confidence index since around ten years. It is a figure between 1 and 5: the more we approach 5, the more the confidence in the supplied forecast is good. In the practice, an indication is supplied for period D+4 / D+5, the other one for period D+6 / D+7, every day being able to benefit from a different forecast, that is be represented in a independent way. We thus supply a global tendency over 24 hours with less and less precise symbols as the range goes away. Concrete examples will be presented. From now on two years, we also publish forecasts to D+8 / J+9, accompanied with a sign of confidence (" good reliability " or " to confirm "). These two days are grouped together on a single map because for us, the described tendency to this term is relevant on a duration about 48 hours with a spatial scale slightly superior to the synoptic scale. So, we avoid producing more than two zones of types of weather over France and we content with giving an evolution for the temperatures (still, in increase or in decline). Newspapers began to publish this information, it should soon be the case of televisions. It is particularly

  10. Wide range radiation monitoring apparatus

    International Nuclear Information System (INIS)

    Goldstein, N.P.

    1983-01-01

    There is described a simple and rugged detector capable of measuring radiation fields over the range of 0.02 R/hr up to 10/8 R/hr or higher. The device consists of an emitter element of high atomic number material which is connected to the center conductor of a signal cable. This emitter element is positioned in a spaced-apart relationship between collector element of a low atomic number material with a gap region between the emitter element and the adjacent collector elements

  11. Extended-range tiltable micromirror

    Science.gov (United States)

    Allen, James J [Albuquerque, NM; Wiens, Gloria J [Newberry, FL; Bronson, Jessica R [Gainesville, FL

    2009-05-05

    A tiltable micromirror device is disclosed in which a micromirror is suspended by a progressive linkage with an electrostatic actuator (e.g. a vertical comb actuator or a capacitive plate electrostatic actuator) being located beneath the micromirror. The progressive linkage includes a pair of torsion springs which are connected together to operate similar to a four-bar linkage with spring joints. The progressive linkage provides a non-linear spring constant which can allow the micromirror to be tilted at any angle within its range substantially free from any electrostatic instability or hysteretic behavior.

  12. Live Fire Range Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    None

    1993-08-01

    The Central Training Academy (CTA) is a DOE Headquarters Organization located in Albuquerque, New Mexico, with the mission to effectively and efficiently educate and train personnel involved in the protection of vital national security interests of DOE. The CTA Live Fire Range (LFR), where most of the firearms and tactical training occurs, is a complex separate from the main campus. The purpose of the proposed action is to expand the LFR to allow more options of implementing required training. The Department of Energy has prepared this Environmental Assessment (EA) for the proposed construction and operation of an expanded Live Fire Range Facility at the Central Training Academy in Albuquerque, New Mexico. Based on the analysis in the EA, DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement is not required and DOE is issuing this Finding of No Significant Impact (FONSI).

  13. Range-Measuring Video Sensors

    Science.gov (United States)

    Howard, Richard T.; Briscoe, Jeri M.; Corder, Eric L.; Broderick, David

    2006-01-01

    Optoelectronic sensors of a proposed type would perform the functions of both electronic cameras and triangulation- type laser range finders. That is to say, these sensors would both (1) generate ordinary video or snapshot digital images and (2) measure the distances to selected spots in the images. These sensors would be well suited to use on robots that are required to measure distances to targets in their work spaces. In addition, these sensors could be used for all the purposes for which electronic cameras have been used heretofore. The simplest sensor of this type, illustrated schematically in the upper part of the figure, would include a laser, an electronic camera (either video or snapshot), a frame-grabber/image-capturing circuit, an image-data-storage memory circuit, and an image-data processor. There would be no moving parts. The laser would be positioned at a lateral distance d to one side of the camera and would be aimed parallel to the optical axis of the camera. When the range of a target in the field of view of the camera was required, the laser would be turned on and an image of the target would be stored and preprocessed to locate the angle (a) between the optical axis and the line of sight to the centroid of the laser spot.

  14. Long-range correlated percolation

    International Nuclear Information System (INIS)

    Weinrib, A.

    1984-01-01

    This paper is a study of the percolation problem with long-range correlations in the site or bond occupations. An extension of the Harris criterion for the relevance of the correlations is derived for the case that the correlations decay as x/sup -a/ for large distances x. For a d the correlations are relevant if dν-2<0. Applying this criterion to the behavior that results when the correlations are relevant, we argue that the new behavior will have ν/sub long/ = 2/a. It is shown that the correlated bond percolation problem is equivalent to a q-state Potts model with quenched disorder in the limit q→1. With the use of this result, a renormalization-group study of the problem is presented, expanding in epsilon = 6-d and in delta = 4-a. In addition to the normal percolation fixed point, we find a new long-range fixed point. The crossover to this new fixed point follows the extended Harris criterion, and the fixed point has exponents ν/sub long/ = 2/a (as predicted) and eta/sub long/ = (1/11)(delta-epsilon). Finally, several results on the percolation properties of the Ising model at its critical point are shown to be in agreement with the predictions of this paper

  15. Expansion-based passive ranging

    Science.gov (United States)

    Barniv, Yair

    1993-01-01

    This paper describes a new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they have been used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts--as well as the other parameters--can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline resulting in a proportionately higher depth accuracy.

  16. Understanding synthesis imaging dynamic range

    Science.gov (United States)

    Braun, R.

    2013-03-01

    We develop a general framework for quantifying the many different contributions to the noise budget of an image made with an array of dishes or aperture array stations. Each noise contribution to the visibility data is associated with a relevant correlation timescale and frequency bandwidth so that the net impact on a complete observation can be assessed when a particular effect is not captured in the instrumental calibration. All quantities are parameterised as function of observing frequency and the visibility baseline length. We apply the resulting noise budget analysis to a wide range of existing and planned telescope systems that will operate between about 100 MHz and 5 GHz to ascertain the magnitude of the calibration challenges that they must overcome to achieve thermal noise limited performance. We conclude that calibration challenges are increased in several respects by small dimensions of the dishes or aperture array stations. It will be more challenging to achieve thermal noise limited performance using 15 m class dishes rather than the 25 m dishes of current arrays. Some of the performance risks are mitigated by the deployment of phased array feeds and more with the choice of an (alt,az,pol) mount, although a larger dish diameter offers the best prospects for risk mitigation. Many improvements to imaging performance can be anticipated at the expense of greater complexity in calibration algorithms. However, a fundamental limitation is ultimately imposed by an insufficient number of data constraints relative to calibration variables. The upcoming aperture array systems will be operating in a regime that has never previously been addressed, where a wide range of effects are expected to exceed the thermal noise by two to three orders of magnitude. Achieving routine thermal noise limited imaging performance with these systems presents an extreme challenge. The magnitude of that challenge is inversely related to the aperture array station diameter.

  17. Wide-range voltage modulation

    International Nuclear Information System (INIS)

    Rust, K.R.; Wilson, J.M.

    1992-06-01

    The Superconducting Super Collider's Medium Energy Booster Abort (MEBA) kicker modulator will supply a current pulse to the abort magnets which deflect the proton beam from the MEB ring into a designated beam stop. The abort kicker will be used extensively during testing of the Low Energy Booster (LEB) and the MEB rings. When the Collider is in full operation, the MEBA kicker modulator will abort the MEB beam in the event of a malfunction during the filling process. The modulator must generate a 14-μs wide pulse with a rise time of less than 1 μs, including the delay and jitter times. It must also be able to deliver a current pulse to the magnet proportional to the beam energy at any time during ramp-up of the accelerator. Tracking the beam energy, which increases from 12 GeV at injection to 200 GeV at extraction, requires the modulator to operate over a wide range of voltages (4 kV to 80 kV). A vacuum spark gap and a thyratron have been chosen for test and evaluation as candidate switches for the abort modulator. Modulator design, switching time delay, jitter and pre-fire data are presented

  18. Chapter 2 Western dominance Piedra Alta terrane

    International Nuclear Information System (INIS)

    2005-01-01

    Piedra Alta Stone includes: geo chemical and geochronology of the granitic complex is located in the SW portion of the crystalline basement of Uruguay. It consists of four thin metamorphic belts separated by a granitic complex - gneissic - migmatítico (CGG) and associated with an important granite, granodiorite, basic or ultrabasic magmatic. Belts north to south are called Arroyo Grande Andresito by renowned Bossi et al. (2000); San Jose (Preciozzi et al., 1991), San Juan (Preciozzi et al, 2005) and Montevideo (Bossi et al., 1993) Pando by renowned Bossi et al. (2000). They are composed of volcano-sedimentary units of different degrees of metamorphism and a set of associated intrusions

  19. Tectonically controlled fan delta and submarine fan sedimentation of late Miocene age, southern Temblor Range, California

    Science.gov (United States)

    Ryder, Robert T.; Thomson, Alan

    1989-01-01

    The Santa Margarita Formation in the southern Temblor Range, composed of conglomerate and subordinate sandstone, evolved as a large complex of fan deltas and submarine fans in late Miocene time. An 80 to 90-m.y.-old granitic basement of the Salinian block and an accompanying 23.5-m.y.-old volcanic field now located in the northern Gabilan Range and the Pinnacles area, respectively, were the primary source terranes. In general, the fan deltas crop out along the west side of the southern Temblor Range, whereas the proximal parts of the submarine fans crop out along the east side of the range. The fan deltas consist of subaerial topset beds and low-angle basinward-dipping subaqueous foreset beds. Strata interpreted to be topset beds are composed largely of conglomerate with thick to very thick horizontal beds and matrix-supported clasts. Most of the thick to very thick conglomerate beds are internally massive and disorganized. Strata interpreted as foreset beds are composed of thick-bedded, large-scale, low-angle, cross-stratified conglomerate and sandstone units which commonly are internally massive. Abundant molluskan macrofossils such as Ostrea and Pecten are present in the subaqueous foreset beds; many have been displaced downslope from their original site of deposition. Conglomerate- and sandstone-filled submarine canyons, through which coarse-grained detritus was transported to the adjacent submarine fans, locally have cut into the foreset beds of the fan deltas. These submarine canyon deposits are generally better stratified than adjacent foreset-bed deposits, and they consist of thick horizontal beds, internally massive or normally graded, arranged in fining- and thinning-upward sequences. Isolated and composite conglomerate- and sandstone-filled channels, which crop out on the east flank of the southern Temblor Range, are interpreted as proximal submarine-fan channel deposits. These channel-form conglomerate and sandstone deposits are characterized by thick

  20. Long-Range Neutron Detection

    International Nuclear Information System (INIS)

    Peurrung, A.J.; Stromswold, D.C.; Hansen, R.R.; Reeder, P.L.; Barnett, D.S.

    1999-01-01

    A neutron detector designed for detecting neutron sources at distances of 50 to 100 m has been constructed and tested. This detector has a large surface area (1 m 2 ) to enhance detection efficiency, and it contains a collimator and shielding to achieve direction sensitivity and reduce background. An unusual feature of the detector is that it contains no added moderator, such as polyethylene, to moderate fast neutrons before they reach the 3 He detector. As a result, the detector is sensitive mainly to thermal neutrons. The moderator-free design reduces the weight of the detector, making it more portable, and it also aids in achieving directional sensitivity and background reduction. Test results show that moderated fission-neutron sources of strength about 3 x 10 5 n/s can be detected at a distance out to 70 m in a counting time of 1000 s. The best angular resolution of the detector is obtained at distances of 30 m or less. As the separation .distance between the source and detector increases, the contribution of scattered neutrons to the measured signal increases with a resultant decrease in the ability to detect the direction to a distant source. Applications for which the long-range detector appears to be suitable include detecting remote neutron sources (including sources in moving vehicles) and monitoring neutron storage vaults for the intrusion of humans and the effects they make on the detected neutron signal. Also, the detector can be used to measure waste for the presence of transuranic material in the presence of high gamma-ray background. A test with a neutron source (3 x 10 5 n/s) in a vehicle showed that the detector could readily measure an increase in count rate at a distance of 10 m for vehicle speeds up to 35 mph (the highest speed tested). These results. indicate that the source should be detectable at this distance at speeds up to 55 mph

  1. Report to Congress on Sustainable Ranges, 2012

    Science.gov (United States)

    2012-05-01

    designated in the SOCAL EIS/OEIS as the USMC Assault Vehicle Maneuver Area, Artillery Firing Positions (AFP), and Assault Maneuver Positions ( AMP ...Description Holloman Ranges consist of Red Rio Range, Centennial Range Oscura Range, and Casa Range. These ranges are the primary training ranges for the...Compatibility Plan AMCOM Aviation and Missile Command AMP Assault Maneuver Positions AMW Amphibious Warfare ANG Air National Guard AO Area of Operations AOC Air

  2. Report to Congress on Sustainable Ranges, 2011

    Science.gov (United States)

    2011-07-01

    Assault Maneuver Positions ( AMP ). SCI is the ONLY maritime training area that can support I MEF Battalion Landings, tactical EFV insertions and live...Range, and Casa range. These ranges are the primary training ranges for the 49th Wing. Ranges support daily air to ground sorties. These ranges also...Compatibility Plan AMCOM Aviation and Missile Command AMP Assault Maneuver Positions AMW Amphibious Warfare ANG Air National Guard AO Area of Operations AOC

  3. Colored Range Searching in Linear Space

    DEFF Research Database (Denmark)

    Grossi, Roberto; Vind, Søren Juhl

    2014-01-01

    In colored range searching, we are given a set of n colored points in d ≥ 2 dimensions to store, and want to support orthogonal range queries taking colors into account. In the colored range counting problem, a query must report the number of distinct colors found in the query range, while...

  4. Radar range measurements in the atmosphere.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2013-02-01

    The earths atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

  5. Directional Wide-Angle Range Finder (DWARF)

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation, the Directional Wide-Angle Range Finder (DWARF) is the creation of a laser range-finder with a wide field-of-view (FOV) and a directional...

  6. Range-Based Auto-Focus Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Maracel Systems and Software Technologies, LLC proposes a revolutionary Range-Based Auto Focus (RBAF) system that will combine externally input range, such as might...

  7. WPC's Short Range Forecast Coded Bulletin

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Short Range Forecast Coded Bulletin. The Short Range Forecast Coded Bulletin describes the expected locations of high and low pressure centers, surface frontal...

  8. Magnetic short range order in Gd

    International Nuclear Information System (INIS)

    Child, H.R.

    1976-01-01

    Quasielastic neutron scattering has been used to investigate magnetic short range order in Gd for 80 0 K 0 K. Short range order exists throughout this range from well below T/sub C/ = 291 0 K to well above it and can be reasonably well described by an anisotropic Orstein-Zernike form for chi

  9. Thermochronologic and geodynamic evolution of the Pontides: Sakarya terrane (Karakaya Complex) and Istanbul terrane, Turkey.

    OpenAIRE

    Federici, Ilaria

    2010-01-01

    An integrated array of analytical methods -including clay mineralogy, vitrinite reflectance, Raman spectroscopy on carbonaceous material, and apatite fission-track analysis- was employed to constrain the thermal and thermochronological evolution of selected portions of the Pontides of northern Turkey. (1) A multimethod investigation was applied for the first time to characterise the thermal history of the Karakaya Complex, a Permo-Triassic subduction-accretion complex cropping out through...

  10. A study of tectonic activity in the Basin-Range Province and on the San Andreas Fault. No. 2: Lithospheric structure, seismicity, and contemporary deformation of the United States Cordillera

    Science.gov (United States)

    Smith, R. B.

    1986-01-01

    The structural evolution of the U.S. Cordillera has been influenced by a variety of tectonic mechanisms including passive margin rifting and sedimentation; arc volcanism; accretion of exotic terranes; intraplate magmatism; and folding and faulting associated with compression and extension processes that have profoundly influenced the lithospheric structure. As a result the Cordilleran crust is laterally inhomogeneous across its 2000 km east-west breadth. It is thin along the West Coast where it has close oceanic affinities. The crust thickens eastward beneath the Sierra Nevada, then thins beneath the Basin-Range. Crustal thickening continues eastward beneath the Colorado Plateau, the Rocky Mountains, and the Great Plains. The total lithospheric thickness attains 65 km in the Basin-Range and increases eastward beneath the Colorado Plateau. The upper-crust, including the crystalline basement of the Cordillera, has P sub G velocities of 6 km/s in the Basin-Range and Rio Grande Rift. Lower P sub G velocities of 5.4 to 5.7 km/s are associated with the youthful Yellowstone, Valles and Long Valley calderas and the Franciscan assemblage of the western coastal margin. Averaged crustal velocity reflects integrated tectonic evolution of the crust-thick silicic bodies, velocity reversals, and a thin crust produce low averaged velocities that are characteristic of a highly attenuated and thermally deformed crust.

  11. Caspian Tern Range - CWHR [ds604

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  12. Great Blue Heron Range - CWHR [ds609

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  13. Common Loon Range - CWHR [ds603

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  14. Northern Leopard Frog Range - CWHR [ds593

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  15. Caspian Tern Range - CWHR [ds604

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  16. Snowy Egret Range - CWHR [ds611

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  17. Western Pond Turtle Range - CWHR [ds598

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  18. California Tiger Salamander Range - CWHR [ds588

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  19. Bank Swallow Range - CWHR [ds606

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  20. Black Swift Range - CWHR [ds605

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  1. Bald Eagle Range - CWHR [ds600

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  2. Bald Eagle Range - CWHR [ds600

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  3. California Tiger Salamander Range - CWHR [ds588

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  4. Oregon Spotted Frog Range - CWHR [ds597

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  5. Black Rail Range - CWHR [ds595

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  6. Cascades Frog Range - CWHR [ds591

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  7. Close range photogrammetry and machine vision

    CERN Document Server

    Atkinson, KB

    1996-01-01

    This book presents the methodology, algorithms, techniques and equipment necessary to achieve real time digital photogrammetric solutions, together with contemporary examples of close range photogrammetry.

  8. Great Egret Range - CWHR [ds610

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  9. Western Pond Turtle Range - CWHR [ds598

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  10. Willow Flycatcher Range - CWHR [ds594

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  11. Bank Swallow Range - CWHR [ds606

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  12. Giant Garter Snake Range - CWHR [ds599

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  13. Arroyo Toad Range - CWHR [ds612

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  14. Software for computing and annotating genomic ranges.

    Science.gov (United States)

    Lawrence, Michael; Huber, Wolfgang; Pagès, Hervé; Aboyoun, Patrick; Carlson, Marc; Gentleman, Robert; Morgan, Martin T; Carey, Vincent J

    2013-01-01

    We describe Bioconductor infrastructure for representing and computing on annotated genomic ranges and integrating genomic data with the statistical computing features of R and its extensions. At the core of the infrastructure are three packages: IRanges, GenomicRanges, and GenomicFeatures. These packages provide scalable data structures for representing annotated ranges on the genome, with special support for transcript structures, read alignments and coverage vectors. Computational facilities include efficient algorithms for overlap and nearest neighbor detection, coverage calculation and other range operations. This infrastructure directly supports more than 80 other Bioconductor packages, including those for sequence analysis, differential expression analysis and visualization.

  15. Software for computing and annotating genomic ranges.

    Directory of Open Access Journals (Sweden)

    Michael Lawrence

    Full Text Available We describe Bioconductor infrastructure for representing and computing on annotated genomic ranges and integrating genomic data with the statistical computing features of R and its extensions. At the core of the infrastructure are three packages: IRanges, GenomicRanges, and GenomicFeatures. These packages provide scalable data structures for representing annotated ranges on the genome, with special support for transcript structures, read alignments and coverage vectors. Computational facilities include efficient algorithms for overlap and nearest neighbor detection, coverage calculation and other range operations. This infrastructure directly supports more than 80 other Bioconductor packages, including those for sequence analysis, differential expression analysis and visualization.

  16. Ultrasonic range measurements on the human body

    NARCIS (Netherlands)

    Weenk, D.; van Beijnum, Bernhard J.F.; Droog, Adriaan; Hermens, Hermanus J.; Veltink, Petrus H.

    2013-01-01

    Ambulatory range estimation on the human body is important for the assessment of the performance of upper- and lower limb tasks outside a laboratory. In this paper an ultrasound sensor for estimating ranges on the human body is presented and validated during gait. The distance between the feet is

  17. Report to Congress on Sustainable Ranges, 2013

    Science.gov (United States)

    2013-04-01

    energy goals and a national broadband infrastructure, while exploring cooperative land-use strategies to reduce congestion on stressed ranges. These...views regarding operational and perceived impacts of Army installations and training activities; and demonstrate an interest in public opinions...successful proof of concept exercises conducted by Naval Special Warfare Command (NSWC) on the USMC Chocolate Mountain Aerial Gunnery Range. Updated

  18. Reference Physiological Ranges for Serum Biochemical Parameters ...

    African Journals Online (AJOL)

    Background: A valid scientific evaluation of the efficacy of HIV vaccines or antiretroviral drugs includes measurement of changes in physiological parameters of subjects from known established baseline reference ranges. This study was designed to establish reference ranges for biochemical parameters among healthy ...

  19. Orthogonal Range Searching on the RAM, Revisited

    DEFF Research Database (Denmark)

    Chan, Timothy M.; Larsen, Kasper Green; Patrascu, Mihai

    2011-01-01

    We present a number of new results on one of the most extensively studied topics in computational geometry, orthogonal range searching. All our results are in the standard word RAM model: We present two data structures for 2-d orthogonal range emptiness. The first achieves O(n lg lg n) space and O...

  20. New data structures for orthogonal range searching

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Brodal, Gerth Stølting; Rauhe, Theis

    2000-01-01

    We present new general techniques for static orthogonal range searching problems in two and higher dimensions. For the general range reporting problem in R3, we achieve query time O(log n+k) using space O(n log1+ε n), where n denotes the number of stored points and k the number of points to be re...

  1. Tests of Gravity Using Lunar Laser Ranging

    Directory of Open Access Journals (Sweden)

    Stephen M. Merkowitz

    2010-11-01

    Full Text Available Lunar laser ranging (LLR has been a workhorse for testing general relativity over the past four decades. The three retroreflector arrays put on the Moon by the Apollo astronauts and the French built arrays on the Soviet Lunokhod rovers continue to be useful targets, and have provided the most stringent tests of the Strong Equivalence Principle and the time variation of Newton’s gravitational constant. The relatively new ranging system at the Apache Point 3.5 meter telescope now routinely makes millimeter level range measurements. Incredibly, it has taken 40 years for ground station technology to advance to the point where characteristics of the lunar retroreflectors are limiting the precision of the range measurements. In this article, we review the gravitational science and technology of lunar laser ranging and discuss prospects for the future.

  2. Perception range prediction for IR pilot sight

    Science.gov (United States)

    Weiss, A. Robert; Großmann, Peter; Repasi, Endre; Ritt, Gunnar; Wittenstein, Wolfgang

    2008-04-01

    The increasing use of IR pilot sight in helicopters calls for a reliable prediction of perception ranges for a variety of objects, especially those needed for orientation and those posing as a potential hazard, like power poles, masts, isolated trees etc. Since the visibility of objects in the IR depends mainly on the temperature differences between those objects and a given background and only marginally on illumination, range prediction techniques used for the visual range or light-amplified vision are only of very limited use. While range predictions based on the Johnson criterion do offer some insight into expected ranges, the inherently nominal nature of distance estimates thus obtained hampers their use for an actual field-deployable pre-flight consulting procedure. In order to overcome those limitations, long-term simultaneous measurements of relevant objects and background temperatures and weather data were carried out and used for temperature prediction from prevalent weather conditions. Together with a perception model derived from extensive observer experiments based on synthetic images of the UH Tiger Pilot Sight Unit we developed a perception range prediction package which is currently evaluated by the weather service of the Bundeswehr. We will present results from the observer experiments together with the derived perception models. These are then compared to actual perception ranges as obtained from flight experiments.

  3. A general approach for cache-oblivious range reporting and approximate range counting

    DEFF Research Database (Denmark)

    Afshani, Peyman; Hamilton, Chris; Zeh, Norbert

    2010-01-01

    We present cache-oblivious solutions to two important variants of range searching: range reporting and approximate range counting. Our main contribution is a general approach for constructing cache-oblivious data structures that provide relative (1+ε)-approximations for a general class of range...

  4. Close Range Sonar System and Method

    National Research Council Canada - National Science Library

    Carter, G. C

    2004-01-01

    A system for close range sonar is provided. The system provides sufficient warning to permit maneuvering to avoid a close encounter even in the forward starboard/port regions, which have been problematic in the past due to ownship noise...

  5. New technologies for submillimeter laser ranging

    Czech Academy of Sciences Publication Activity Database

    Blažek, J.; Procházka, I.; Kodet, J.; Pánek, Petr

    -, 301-303 (2011), s. 397-401 ISSN 1662-8985 Institutional research plan: CEZ:AV0Z20670512 Keywords : time measurement * laser ranging Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  6. African Journal of Range and Forage Science

    African Journals Online (AJOL)

    The African Journal of Range & Forage Science is the leading rangeland and pastoral journal in Africa. The Journal is dedicated to publishing quality original material that advances rangeland ecology and pasture management in Africa. Read more abou the journal here.

  7. Long-Range Order in β Brass

    DEFF Research Database (Denmark)

    Norvell, J.C.; Als-Nielsen, Jens Aage

    1970-01-01

    The long-range order parameter M of β brass has been determined from measurements of the intensity of superlattice reflections of Bragg-scattered neutrons. Over the whole temperature range T=300 °K to T=Tc=736 °K, the data are in remarkable agreement with the prediction for the compressible Ising...... bcc lattice with only nearest-neighbor interactions. © 1970 The American Physical Society...

  8. Evolved dispersal strategies at range margins

    OpenAIRE

    Dytham, Calvin

    2009-01-01

    Dispersal is a key component of a species's ecology and will be under different selection pressures in different parts of the range. For example, a long-distance dispersal strategy suitable for continuous habitat at the range core might not be favoured at the margin, where the habitat is sparse. Using a spatially explicit, individual-based, evolutionary simulation model, the dispersal strategies of an organism that has only one dispersal event in its lifetime, such as a plant or sessile anima...

  9. Normal range of human dietary sodium intake

    DEFF Research Database (Denmark)

    McCarron, David A; Kazaks, Alexandra G; Geerling, Joel C

    2013-01-01

    The recommendation to restrict dietary sodium for management of hypertensive cardiovascular disease assumes that sodium intake exceeds physiologic need, that it can be significantly reduced, and that the reduction can be maintained over time. In contrast, neuroscientists have identified neural...... circuits in vertebrate animals that regulate sodium appetite within a narrow physiologic range. This study further validates our previous report that sodium intake, consistent with the neuroscience, tracks within a narrow range, consistent over time and across cultures....

  10. Makran Mountain Range, Iran and Pakistan

    Science.gov (United States)

    1983-01-01

    The long folded mountain ridges and valleys of the coastal Makran Ranges of Iran and Pakistan (26.0N, 63.0E) illustrate the classical Trellis type of drainage pattern, common in this region. The Dasht River and its tributaries is the principal drainage network for this area. To the left, the continental drift of the northward bound Indian sub-continent has caused the east/west parallel ranges to bend in a great northward arc.

  11. Organic and free-range egg production

    OpenAIRE

    Hammershøj, M.

    2011-01-01

    This chapter includes information on the development of the free range and the organic egg production and their market shares in different countries. Consumer behaviour is investigated particularly in relation to the price and availability of non-cage eggs. Regulations on the production of free range and organic eggs and their present and future impact are examined. Nutrient supply, animal welfare, productivity, safety and environmental impact of the types of egg production are covered with a...

  12. Ranges of protons in biological targets

    Science.gov (United States)

    Pavlovič, Márius; Hammerle, Andreas

    2017-08-01

    The paper introduces a simple fitting function for quick assessment of proton ranges in biological targets and human tissues. The function has been found by fitting an extensive data set of Monte Carlo proton ranges obtained with the aid of the SRIM-2013 code. The data has been collected for 28 different targets at 8 energies in the interval from 60 MeV to 220 MeV. The paper shows that at a given kinetic proton-beam energy, the Monte Carlo ranges can be satisfactorily fitted by a power function that depends solely on the target density. This is a great advantage for targets, for which the exact chemical composition is not known, or the mean ionizing potential is not reliably known. The satisfactory fit is meant as the fit that stays within the natural range straggling of the Monte Carlo ranges. In the second step, the energy-scaling yielding a universal fitting formula for proton ranges as a function of proton-beam energy and target density is introduced and discussed.

  13. Range charts and no-space graphs

    Science.gov (United States)

    Edwards, L.E.

    1978-01-01

    No-space graphs present one solution to the familiar problem: given data on the occurrence of fossil taxa in separate, well-sampled sections, determine a range chart; that is, a reasonable working hypothesis of the total range in the area in question of each taxon studied. The solution presented here treats only the relative sequence of biostratigraphic events (first and last occurrences of taxa) and does not attempt to determine an amount of spacing between events. Relative to a hypothesized sequence, observed events in any section may be in-place or out-of-place. Out-of-place events may indicate (1) the event in question reflects a taxon that did not fill its entire range (unfilled-range event), or (2) the event in question indicates a need for the revision of the hypothesized sequence. A graph of relative position only (no-space graph) can be used to facilitate the recognition of in-place and out-of-place events by presenting a visual comparison of the observations from each section with the hypothesized sequence. The geometry of the graph as constructed here is such that in-place events will lie along a line series and out-of-place events will lie above or below it. First-occurrence events below the line series and last-occurrence events above the line series indicate unfilled ranges. First-occurrence events above the line series and last-occurrence events below the line series indicate a need for the revision of the hypothesis. Knowing this, the stratigrapher considers alternative positionings of the line series as alternative range hypotheses and seeks the line series that best fits his geologic and paleontologic judgment. No-space graphs are used to revise an initial hypothesis until a final hypothesis is reached. In this final hypothesis every event is found in-place in at least one section, and all events in all sections may be interpreted to represent in-place events or unfilled-range events. No event may indicate a need for further range revision. The

  14. Variability of Diurnal Temperature Range During Winter Over Western Himalaya: Range- and Altitude-Wise Study

    Science.gov (United States)

    Shekhar, M. S.; Devi, Usha; Dash, S. K.; Singh, G. P.; Singh, Amreek

    2018-04-01

    The current trends in diurnal temperature range, maximum temperature, minimum temperature, mean temperature, and sun shine hours over different ranges and altitudes of Western Himalaya during winter have been studied. Analysis of 25 years of data shows an increasing trend in diurnal temperature range over all the ranges and altitudes of Western Himalaya during winter, thereby confirming regional warming of the region due to present climate change and global warming. Statistical studies show significant increasing trend in maximum temperature over all the ranges and altitudes of Western Himalaya. Minimum temperature shows significant decreasing trend over Pir Panjal and Shamshawari range and significant increasing trend over higher altitude of Western Himalaya. Similarly, sunshine hours show significant decreasing trend over Karakoram range. There exists strong positive correlation between diurnal temperature range and maximum temperature for all the ranges and altitudes of Western Himalaya. Strong negative correlation exists between diurnal temperature range and minimum temperature over Shamshawari and Great Himalaya range and lower altitude of Western Himalaya. Sunshine hours show strong positive correlation with diurnal temperature range over Pir Panjal and Great Himalaya range and lower and higher altitudes.

  15. Mercury's Global Topography from Radar Ranging Data

    Science.gov (United States)

    Anderson, J. D.; Schubert, G.; Asmar, S. W.; Jurgens, R. F.; Lau, E. L.; Moore, W. B.; Slade, M. A., III; Standish, E. M., Jr.

    2001-01-01

    When Mercury's radius is expanded in Legendre functions to the second degree and order, the systematic error in radar ranging data is reduced substantially. Previously, data spanning an observing interval from 1966 to 1990 were used to infer an equatorial ellipticity (a - b)/a = (540 +/- 54) X 10(exp -6) and a center-of-figure minus center-of-mass offset of (640 +/- 78) m. The magnitude of this equatorial center of figure offset implies an excess crustal thickness of 12 km or less, comparable to the Moon's excess. By comparing the equatorial ellipticity with the Mariner 10 gravity field, and assuming Airy isostatic compensation, bounds on crustal thickness can be derived. Mercury's crustal thickness is in the range from 100 to 300 km. The Mercury radar ranging observing interval has been extended from 1966 to the present. In addition, improvements in data reduction techniques have resulted in a set of Mercury ranging data less affected by systematic error, in particular the biases introduced by local topographic variations. We use this new set of reduced ranging data to improve Mercury's global topography and center-of-figure minus center-of-mass offset. New results on crustal thickness are derived, and prospects for further improvement with Mercury Orbiter data are discussed.

  16. Adaptive and Approximate Orthogonal Range Counting

    DEFF Research Database (Denmark)

    Chan, Timothy M.; Wilkinson, Bryan Thomas

    2013-01-01

    -case optimal query time O(log_w n). We give an O(n loglog n)-space adaptive data structure that improves the query time to O(loglog n + log_w k), where k is the output count. When k=O(1), our bounds match the state of the art for the 2-D orthogonal range emptiness problem [Chan, Larsen, and Pătraşcu, SoCG 2011......]. •We give an O(n loglog n)-space data structure for approximate 2-D orthogonal range counting that can compute a (1+δ)-factor approximation to the count in O(loglog n) time for any fixed constant δ>0. Again, our bounds match the state of the art for the 2-D orthogonal range emptiness problem. •Lastly......Close Abstract We present three new results on one of the most basic problems in geometric data structures, 2-D orthogonal range counting. All the results are in the w-bit word RAM model. •It is well known that there are linear-space data structures for 2-D orthogonal range counting with worst...

  17. A study of the sensitivity of long-range passive ranging techniques to atmospheric scintillation

    CSIR Research Space (South Africa)

    De Villiers, J

    2012-04-01

    Full Text Available This work aims to quantify and improve the sensitivity of monocular passive ranging techniques in sequences that are degraded by the the quasi-periodic inter frame motion and localised blurring associated with atmospheric scintillation. Ranges from...

  18. The host range of Phomopsis cirsii

    DEFF Research Database (Denmark)

    Leth, Vibeke; Andreasen, Christian

    2012-01-01

    . An isolate PKDK101 of the fungus Phomopsiscirsii, which is virulent to C. arvense causing stem canker and die back was chosen to test the specificity of the fungus. A series of infection trials were successively carried out on 127 plant species (incl. ssp. and var.) belonging to 16 families in greenhouses...... in order to encircle the host range of P. cirsii. Susceptible plant species were found only in the thistle group (Cardueae) which contained 34 species belonging to 12 genera. Susceptible species were found in thirteen of these genera. Highly susceptible species included Carduusacanthoides...... echinus, Cirsiumvulgare and Cynaracardunculusvar.scolymus (artichoke) with symptoms such as restricted necrotic leaf spots and too early senescence or death of entire leaf. Eleven hosts for P. cirsii were recorded but despite the expanded range of hosts we expect that its host range will be within...

  19. Validating data analysis of broadband laser ranging

    Science.gov (United States)

    Rhodes, M.; Catenacci, J.; Howard, M.; La Lone, B.; Kostinski, N.; Perry, D.; Bennett, C.; Patterson, J.

    2018-03-01

    Broadband laser ranging combines spectral interferometry and a dispersive Fourier transform to achieve high-repetition-rate measurements of the position of a moving surface. Telecommunications fiber is a convenient tool for generating the large linear dispersions required for a dispersive Fourier transform, but standard fiber also has higher-order dispersion that distorts the Fourier transform. Imperfections in the dispersive Fourier transform significantly complicate the ranging signal and must be dealt with to make high-precision measurements. We describe in detail an analysis process for interpreting ranging data when standard telecommunications fiber is used to perform an imperfect dispersive Fourier transform. This analysis process is experimentally validated over a 27-cm scan of static positions, showing an accuracy of 50 μm and a root-mean-square precision of 4.7 μm.

  20. Three-dimensional dynamic range reduction techniques

    Science.gov (United States)

    Harding, Kevin G.; Qian, Xiaoping

    2004-02-01

    A significant limitation of the application of 3D structured light systems has been the large dynamic range of reflectivity of typical parts such as machined parts. The advent of digital cameras have helped this problem to some extent by providing a larger dynamic range of detection, but often parts must still be coated with white paint or powder to get a good enough return for 3D measurement techniques such as structured light. This paper will present an overview of methods that have been used to minimize the range of light reflections from many parts including polarization, multiple exposure, multiple viewing and masking techniques. Also presented will be methods of analysis such as phase analysis techniques which can provide improved robustness. Finally, we will discuss the pros and cons of these options as applied to the application of 3D structured light techniques to machined metal parts.

  1. Zero range three-particle equations

    International Nuclear Information System (INIS)

    Noyes, H.P.; Zeiger, E.M.

    1978-04-01

    In order to separate the entire effect of two-particle on-shell scatterings in three-particle systems from the effects of hidden mesonic degrees of freedom (off-shell effects and three-body forces), the zero range limit of the Karlsson-Zeiger equations. Although the Faddeev equations are ambiguous in this limit, the KZ equations remain well defined. Using only two-particle phase shifts, binding energies, and reduced widths, these zero-range equations uniquely predict the three-particle observables which would occur in the absence of hidden mesonic degrees of freedom. The three-particle amplitudes possess all requisite physical symmetry properties, and can be proved to be unitary if the spectator basis is orthonormal and complete. Possible extensions of the scheme for the analysis of three-particle final states, to zero range four-particle equations, and to relativistic systems are conjectured

  2. Long range correlations in condensed matter

    International Nuclear Information System (INIS)

    Bochicchio, R.C.

    1990-01-01

    Off diagonal long range order (ODLRO) correlations are strongly related with the generalized Bose-Einstein condensation. Under certain boundary conditions, one implies the other. These phenomena are of great importance in the description of quantum situations with a macroscopic manifestation (superfluidity, superconductivity, etc.). Since ion pairs are not bosons, the definition of ODLRO is modified. The information contained with the 2-particle propagator (electron pairs) and the consequences that lead to pairs statistics are shown in this presentation. The analogy between long range correlations and fluids is also analyzed. (Author). 17 refs

  3. High dynamic range imaging sensors and architectures

    CERN Document Server

    Darmont, Arnaud

    2013-01-01

    Illumination is a crucial element in many applications, matching the luminance of the scene with the operational range of a camera. When luminance cannot be adequately controlled, a high dynamic range (HDR) imaging system may be necessary. These systems are being increasingly used in automotive on-board systems, road traffic monitoring, and other industrial, security, and military applications. This book provides readers with an intermediate discussion of HDR image sensors and techniques for industrial and non-industrial applications. It describes various sensor and pixel architectures capable

  4. Integrable Structure of Multispecies Zero Range Process

    Science.gov (United States)

    Kuniba, Atsuo; Okado, Masato; Watanabe, Satoshi

    2017-06-01

    We present a brief review on integrability of multispecies zero range process in one dimension introduced recently. The topics range over stochastic R matrices of quantum affine algebra U_q (A^{(1)}_n), matrix product construction of stationary states for periodic systems, q-boson representation of Zamolodchikov-Faddeev algebra, etc. We also introduce new commuting Markov transfer matrices having a mixed boundary condition and prove the factorization of a family of R matrices associated with the tetrahedron equation and generalized quantum groups at a special point of the spectral parameter.

  5. Introduction to sensors for ranging and imaging

    CERN Document Server

    Brooker, Graham

    2009-01-01

    ""This comprehensive text-reference provides a solid background in active sensing technology. It is concerned with active sensing, starting with the basics of time-of-flight sensors (operational principles, components), and going through the derivation of the radar range equation and the detection of echo signals, both fundamental to the understanding of radar, sonar and lidar imaging. Several chapters cover signal propagation of both electromagnetic and acoustic energy, target characteristics, stealth, and clutter. The remainder of the book introduces the range measurement process, active ima

  6. Safety assessment of outdoor live fire range

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-05-01

    The following Safety Assessment (SA) pertains to the outdoor live fire range facility (LFR). The purpose of this facility is to supplement the indoor LFR. In particular it provides capacity for exercises that would be inappropriate on the indoor range. This SA examines the risks that are attendant to the training on the outdoor LFR. The outdoor LFR used by EG&G Mound is privately owned. It is identified as the Miami Valley Shooting Grounds. Mondays are leased for the exclusive use of EG&G Mound.

  7. Range data in vehicle dynamic simulation

    OpenAIRE

    Nybacka, Mikael; Fredriksson, Håkan; Hyyppä, Kalevi

    2009-01-01

    This paper presents a way to merge range data into the vehicle dynamic simulation software CarSim 7.1. The range data consists of measurements describing the surface of a road, and thus, creates a close to real life 3D simulation environment. This reduces the discrepancy between the real life tests and simulation of vehicle suspension systems, dampers, springs, etc. It is important for the vehicle industry to represent a real life environment in the simulation software in order to increase th...

  8. Range conditions for a spherical mean transform

    KAUST Repository

    Agranovsky, Mark

    2009-07-01

    The paper is devoted to the range description of the Radon type transform that averages a function over all spheres centered on a given sphere. Such transforms arise naturally in thermoacoustic tomography, a novel method of medical imaging. Range descriptions have recently been obtained for such transforms, and consisted of smoothness and support conditions, moment conditions, and some additional orthogonality conditions of spectral nature. It has been noticed that in odd dimensions, surprisingly, the moment conditions are superfluous and can be eliminated. It is shown in this text that in fact the same happens in any dimension.

  9. Radar meteors range distribution model. I. Theory

    Czech Academy of Sciences Publication Activity Database

    Pecinová, Drahomíra; Pecina, Petr

    2007-01-01

    Roč. 37, č. 2 (2007), s. 83-106 ISSN 1335-1842 R&D Projects: GA ČR GA205/03/1405 Institutional research plan: CEZ:AV0Z10030501 Keywords : physics of meteors * radar meteors * range distribution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  10. Look Ahead: Long-Range Learning Plans

    Science.gov (United States)

    Weinstein, Margery

    2010-01-01

    Faced with an unsteady economy and fluctuating learning needs, planning a learning strategy designed to last longer than the next six months can be a tall order. But a long-range learning plan can provide a road map for success. In this article, four companies (KPMG LLP, CarMax, DPR Construction, and EMC Corp.) describe their learning plans, and…

  11. Compressed Data Structures for Range Searching

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Vind, Søren Juhl

    2015-01-01

    We study the orthogonal range searching problem on points that have a significant number of geometric repetitions, that is, subsets of points that are identical under translation. Such repetitions occur in scenarios such as image compression, GIS applications and in compactly representing sparse...

  12. Medium-range fire weather forecasts

    Science.gov (United States)

    J.O. Roads; K. Ueyoshi; S.C. Chen; J. Alpert; F. Fujioka

    1991-01-01

    The forecast skill of theNational Meteorological Center's medium range forecast (MRF) numerical forecasts of fire weather variables is assessed for the period June 1,1988 to May 31,1990. Near-surface virtual temperature, relative humidity, wind speed and a derived fire weather index (FWI) are forecast well by the MRF model. However, forecast relative humidity has...

  13. A range of equipment for dental radiography

    International Nuclear Information System (INIS)

    Bergman, G.P.M.; Clement, S.L.

    1980-01-01

    A brief review of the history of dental radiography is followed by a description of the latest Philips equipment, ranging from compact units for intra-oral radiography to advanced systems for panoramic techniques and skull radiography. The advantages of automatic exposure control and automatic film processing are also discussed. In conclusion, some probable future trends are forecast. (Auth.)

  14. Problems in implementing improved range management on ...

    African Journals Online (AJOL)

    Problems in implementing improved range management on common lands in Africa: An Australian perspective. Squires V.R., Mann T.L., Andrew M.H.. Abstract. Rangeland/livestock development in Africa is reviewed and lessons learnt from successes and failures are noted. Focuses on sustainable resource development in ...

  15. On the validity range of piston theory

    CSIR Research Space (South Africa)

    Meijer, M-C

    2015-06-01

    Full Text Available The basis of linear piston theory in unsteady potential flow is used in this work to develop a quantitative treatment of the validity range of piston theory. In the limit of steady flow, velocity perturbations from Donov’s series expansion...

  16. Reference Physiological Ranges for Serum Biochemical Parameters ...

    African Journals Online (AJOL)

    clinical trials and scaling up of ARV drugs among AIDS patients. ... parametric and non parametric statistics for analyses with 2.5 and 97.5 percentiles considered ..... Physiological Ranges for Plasma Biochemical Parameters among Adult Healthy Cameroonians. Urban. Rural. Males. Females. Males. Females. Parameter.

  17. Long-range terms in atomic collisions

    International Nuclear Information System (INIS)

    McGuire, J.H.; Weaver, O.L.

    1986-01-01

    Various separations, or ''gauge choices,'' are possible for the decomposition of the total Hamiltonian into electronic and internuclear terms. We show that, for one particular choice, all long-range Coulomb terms are associated with the internuclear motion. The potential then associated with electronic transitions is non-Coulombic. Some practical consequences of this gauge choice are discussed

  18. Resources and Long-Range Forecasts

    Science.gov (United States)

    Smith, Waldo E.

    1973-01-01

    The author argues that forecasts of quick depletion of resources in the environment as a result of overpopulation and increased usage may not be free from error. Ignorance still exists in understanding the recovery mechanisms of nature. Long-range forecasts are likely to be wrong in such situations. (PS)

  19. Low Probability of Intercept Laser Range Finder

    Science.gov (United States)

    2017-07-19

    performs the signal processing . Processor 30 performs a continuous sweep over the photodetector 38 output to isolate and amplify the optical signals ...December 2017 The below identified patent application is available for licensing. Requests for information should be addressed to...1 of 12 LOW PROBABILITY OF INTERCEPT LASER RANGE FINDER STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be

  20. Extended-range order in glasses

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, A.J.G.; Price, D.L.; Saboungi, M.L. [Argonne National Lab., IL (United States); Egami, T.; Hu, Rui-Zhong [Pennsylvania Univ., Philadelphia, PA (United States); Howells, W.S. [Rutherford Appleton Lab., Chilton (United Kingdom)

    1994-03-01

    A new type of order is identified in complex glasses, characterized by diffraction peaks at values of the wave vector below those typical of intermediate-range order. Combined neutron and anomalous x-ray diffraction studies of one glass exhibiting this behavior, vitreous rubidium germanate, indicate it to be associated with chemical ordering of the two cations with respect to each other.

  1. Optimal Static Range Reporting in One Dimension

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Brodal, Gerth Stølting; Rauhe, Theis

    2001-01-01

    We consider static one dimensional range searching problems. These problems are to build static data structures for an integer set S \\subseteq U, where U = \\{0,1,\\dots,2^w-1\\}, which support various queries for integer intervals of U. For the query of reporting all integers in S contained within...

  2. Short range order of selenite glasses

    Czech Academy of Sciences Publication Activity Database

    Neov, S.; Gerasimova, I.; Yordanov, S.; Lakov, L.; Mikula, Pavol; Lukáš, Petr

    1999-01-01

    Roč. 40, č. 2 (1999), s. 111-112 ISSN 0031-9090 R&D Projects: GA AV ČR KSK1010104 Keywords : short range * selenite glasses Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.822, year: 1999

  3. Short range radio research in Twente

    NARCIS (Netherlands)

    Meijerink, Arjan

    2010-01-01

    The research and education by the Telecommunication Engineering Group at the University of Twente is dedicated to physical layer topics in communications. Three research tracks have prominence: Short Range Radio, Microwave Photonics, and Electromagnetic Compatibility. Arjan is active in the Short

  4. System for accurate ranging of meteor trails

    International Nuclear Information System (INIS)

    Tshebotaryov, R.P.; Sidorin, V.N.

    1970-01-01

    The necessity of precise ranging of meteor trails is emphasised possible methods are considered. A scheme with a non ius circular trace and intensity indication giving an unique for meteor radar accuracy ± 50 m is described in detail. Results are given of experimental and practical work of the system

  5. Measuring volatility with the realized range

    NARCIS (Netherlands)

    M.P.E. Martens (Martin); D.J.C. van Dijk (Dick)

    2006-01-01

    textabstractRealized variance, being the summation of squared intra-day returns, has quickly gained popularity as a measure of daily volatility. Following Parkinson (1980) we replace each squared intra-day return by the high-low range for that period to create a novel and more efficient estimator

  6. Great Basin Experimental Range: Annotated bibliography

    Science.gov (United States)

    E. Durant McArthur; Bryce A. Richardson; Stanley G. Kitchen

    2013-01-01

    This annotated bibliography documents the research that has been conducted on the Great Basin Experimental Range (GBER, also known as the Utah Experiment Station, Great Basin Station, the Great Basin Branch Experiment Station, Great Basin Experimental Center, and other similar name variants) over the 102 years of its existence. Entries were drawn from the original...

  7. Method and apparatus for coherent burst ranging

    Science.gov (United States)

    Wachter, Eric A.; Fisher, Walter G.

    1998-01-01

    A high resolution ranging method is described utilizing a novel modulated waveform, hereafter referred to as coherent burst modulation. In the coherent burst method, high frequency modulation of an acoustic or electromagnetic transmitter, such as a laser, is performed at a modulation frequency. This modulation frequency is transmitted quasi-continuously in the form of interrupted bursts of radiation. Energy from the transmitter is directed onto a target, interacts with the target, and the returning energy is collected. The encoded burst pattern contained in the collected return signal is detected coherently by a receiver that is tuned so as to be principally sensitive to the modulation frequency. The receiver signal is processed to determine target range using both time-of-flight of the burst envelope and phase shift of the high frequency modulation. This approach effectively decouples the maximum unambiguous range and range resolution relationship of earlier methods, thereby allowing high precision ranging to be conducted at arbitrarily long distances using at least one burst of encoded energy. The use of a receiver tuned to the high frequency modulation contained within the coherent burst vastly improves both sensitivity in the detection of the target return signal and rejection of background interferences, such as ambient acoustic or electromagnetic noise. Simultaneous transmission at several energies (or wavelengths) is possible by encoding each energy with a separate modulation frequency or pattern; electronic demodulation at the receiver allows the return pattern for each energy to be monitored independently. Radial velocity of a target can also be determined by monitoring change in phase shift of the return signal as a function of time.

  8. Metrological large range scanning probe microscope

    International Nuclear Information System (INIS)

    Dai Gaoliang; Pohlenz, Frank; Danzebrink, Hans-Ulrich; Xu Min; Hasche, Klaus; Wilkening, Guenter

    2004-01-01

    We describe a metrological large range scanning probe microscope (LR-SPM) with an Abbe error free design and direct interferometric position measurement capability, aimed at versatile traceable topographic measurements that require nanometer accuracy. A dual-stage positioning system was designed to achieve both a large measurement range and a high measurement speed. This dual-stage system consists of a commercially available stage, referred to as nanomeasuring machine (NMM), with a motion range of 25 mmx25 mmx5 mm along x, y, and z axes, and a compact z-axis piezoelectric positioning stage (compact z stage) with an extension range of 2 μm. The metrological LR-SPM described here senses the surface using a stationary fixed scanning force microscope (SFM) head working in contact mode. During operation, lateral scanning of the sample is performed solely by the NMM. Whereas the z motion, controlled by the SFM signal, is carried out by a combination of the NMM and the compact z stage. In this case the compact z stage, with its high mechanical resonance frequency (greater than 20 kHz), is responsible for the rapid motion while the NMM simultaneously makes slower movements over a larger motion range. To reduce the Abbe offset to a minimum the SFM tip is located at the intersection of three interferometer measurement beams orientated in x, y, and z directions. To improve real time performance two high-end digital signal processing (DSP) systems are used for NMM positioning and SFM servocontrol. Comprehensive DSP firmware and Windows XP-based software are implemented, providing a flexible and user-friendly interface. The instrument is able to perform large area imaging or profile scanning directly without stitching small scanned images. Several measurements on different samples such as flatness standards, nanostep height standards, roughness standards as well as sharp nanoedge samples and 1D gratings demonstrate the outstanding metrological capabilities of the instrument

  9. Normal range of gastric emptying in children

    International Nuclear Information System (INIS)

    Thomas, P.; Collins, C.; Francis, L.; Henry, R.; O'Loughlin, E.; John Hunter Children's Hospital, Newcastle, NSW

    1999-01-01

    Full text: As part of a larger study looking at gastric emptying times in cystic fibrosis, we assessed the normal range of gastric emptying in a control group of children. Thirteen children (8 girls, 5 boys) aged 4-15 years (mean 10) were studied. Excluded were children with a history of relevant gastrointestinal medical or surgical disease, egg allergy or medication affecting gastric emptying. Imaging was performed at 08.00 h after an overnight fast. The test meal was consumed in under 15 min and comprised one 50 g egg, 80 g commercial pancake mix, 10 ml of polyunsaturated oil, 40 ml of water and 30 g of jam. The meal was labelled with 99 Tc m -macroaggregates of albumin. Water (150 ml) was also consumed with the test meal. One minute images of 128 x 128 were acquired over the anterior and posterior projections every 5 min for 30 min, then every 15 min until 90 min with a final image at 120 min. Subjects remained supine for the first 60 min, after which they were allowed to walk around. A time-activity curve was generated using the geometric mean of anterior and posterior activity. The half emptying time ranged from 55 to 107 min (mean 79, ± 2 standard deviations 43-115). Lag time (time for 5% to leave stomach) ranged from 2 to 26 min (mean 10). The percent emptied at 60 min ranged from 47 to 73% (mean 63%). There was no correlation of half emptying time with age. The normal reference range for a test meal of pancakes has been established for 13 normal children

  10. Individual Ranging Behaviour Patterns in Commercial Free-Range Layers as Observed through RFID Tracking.

    Science.gov (United States)

    Larsen, Hannah; Cronin, Greg M; Gebhardt-Henrich, Sabine G; Smith, Carolynn L; Hemsworth, Paul H; Rault, Jean-Loup

    2017-03-09

    In this exploratory study, we tracked free-range laying hens on two commercial flocks with Radio Frequency Identification (RFID) technology with the aim to examine individual hen variation in range use. Three distinct outdoor zones were identified at increasing distances from the shed; the veranda [0-2.4 m], close range [2.4-11.4 m], and far range [>11.4 m]. Hens' movements between these areas were tracked using radio frequency identification technology. Most of the hens in both flocks (68.6% in Flock A, and 82.2% in Flock B) accessed the range every day during the study. Of the hens that accessed the range, most hens accessed all three zones (73.7% in Flock A, and 84.5% in Flock B). Hens spent half of their time outdoors in the veranda area. Within-individual consistency of range use (daily duration and frequency) varied considerably, and hens which were more consistent in their daily range use spent more time on the range overall ( p < 0.001). Understanding variation within and between individuals in ranging behaviour may help elucidate the implications of ranging for laying hens.

  11. Comparison of range migration correction algorithms for range-Doppler processing

    Science.gov (United States)

    Uysal, Faruk

    2017-07-01

    The next generation digital radars are able to provide high-range resolution by the advancement of radar hardware technologies. These systems take advantage of coherent integration and Doppler processing technique to increase the target's signal-to-noise ratio. Due to the high-range resolution (small range cells) and fast target motion, a target migrates through multiple range cells within a coherent processing interval. Range cell migration (also known as range walk) occurs and degrades the coherent integration gain. There are many approaches in the literature to correct these unavoidable effects and focus the target in the range-Doppler domain. We demonstrate some of these methods on an operational frequency-modulated continuous-wave (FMCW) radar and point out practical issues in the application.

  12. High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

    Science.gov (United States)

    Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

    2016-01-01

    We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

  13. Contrasting Work Fluctuations and Distributions in Systems with Short-Range and Long-Range Correlations.

    Science.gov (United States)

    Kirkpatrick, T R; Bhattacherjee, J K; Sengers, J V

    2017-07-21

    It is shown that the work fluctuations and work distribution functions are fundamentally different in systems with short-range versus long-range correlations. The two cases considered with long-range correlations are magnetic work fluctuations in an equilibrium isotropic ferromagnet and work fluctuations in a nonequilibrium fluid with a temperature gradient. The long-range correlations in the former case are due to equilibrium Goldstone modes, while in the latter they are due to generic nonequilibrium effects. The magnetic case is of particular interest, since an external magnetic field can be used to tune the system from one with long-range correlations to one with only short-range correlations. It is shown that in systems with long-range correlations the work distribution is extraordinarily broad compared to systems with only short-range correlations. Surprisingly, these results imply that fluctuation theorems such as the Jarzynski fluctuation theorem are more useful in systems with long-range correlations than in systems with short-range correlations.

  14. Visual Control of Robots Using Range Images

    Directory of Open Access Journals (Sweden)

    Fernando Torres

    2010-08-01

    Full Text Available In the last years, 3D-vision systems based on the time-of-flight (ToF principle have gained more importance in order to obtain 3D information from the workspace. In this paper, an analysis of the use of 3D ToF cameras to guide a robot arm is performed. To do so, an adaptive method to simultaneous visual servo control and camera calibration is presented. Using this method a robot arm is guided by using range information obtained from a ToF camera. Furthermore, the self-calibration method obtains the adequate integration time to be used by the range camera in order to precisely determine the depth information.

  15. OPTIMAL AIRCRAFT TRAJECTORIES FOR SPECIFIED RANGE

    Science.gov (United States)

    Lee, H.

    1994-01-01

    For an aircraft operating over a fixed range, the operating costs are basically a sum of fuel cost and time cost. While minimum fuel and minimum time trajectories are relatively easy to calculate, the determination of a minimum cost trajectory can be a complex undertaking. This computer program was developed to optimize trajectories with respect to a cost function based on a weighted sum of fuel cost and time cost. As a research tool, the program could be used to study various characteristics of optimum trajectories and their comparison to standard trajectories. It might also be used to generate a model for the development of an airborne trajectory optimization system. The program could be incorporated into an airline flight planning system, with optimum flight plans determined at takeoff time for the prevailing flight conditions. The use of trajectory optimization could significantly reduce the cost for a given aircraft mission. The algorithm incorporated in the program assumes that a trajectory consists of climb, cruise, and descent segments. The optimization of each segment is not done independently, as in classical procedures, but is performed in a manner which accounts for interaction between the segments. This is accomplished by the application of optimal control theory. The climb and descent profiles are generated by integrating a set of kinematic and dynamic equations, where the total energy of the aircraft is the independent variable. At each energy level of the climb and descent profiles, the air speed and power setting necessary for an optimal trajectory are determined. The variational Hamiltonian of the problem consists of the rate of change of cost with respect to total energy and a term dependent on the adjoint variable, which is identical to the optimum cruise cost at a specified altitude. This variable uniquely specifies the optimal cruise energy, cruise altitude, cruise Mach number, and, indirectly, the climb and descent profiles. If the optimum

  16. Middle Range Theory of Traumatic Childbirth

    Science.gov (United States)

    2015-01-01

    A middle range theory of traumatic childbirth was developed using Morse’s method of theoretical coalescence. The scope of this qualitative theory was increased by formalizing the connections between 14 individual studies all conducted by the same researcher on the same topic, with different groups, using different research designs and different types of analyses. Axioms were derived from this research program along with attributes of traumatic childbirth, posttraumatic stress, and secondary traumatic stress. This middle range theory addresses the long-term chronic consequences of a traumatic birth for mothers including its impact on breastfeeding, subsequent childbirth, and the anniversary of birth trauma. The impact on fathers and clinicians present at the traumatic birth is highlighted as secondary traumatic stress comes into play. Troubling glimpses of difficulties in mother–infant bonding are revealed. PMID:28462301

  17. Middle Range Theory of Traumatic Childbirth

    Directory of Open Access Journals (Sweden)

    Cheryl Tatano Beck

    2015-03-01

    Full Text Available A middle range theory of traumatic childbirth was developed using Morse’s method of theoretical coalescence. The scope of this qualitative theory was increased by formalizing the connections between 14 individual studies all conducted by the same researcher on the same topic, with different groups, using different research designs and different types of analyses. Axioms were derived from this research program along with attributes of traumatic childbirth, posttraumatic stress, and secondary traumatic stress. This middle range theory addresses the long-term chronic consequences of a traumatic birth for mothers including its impact on breastfeeding, subsequent childbirth, and the anniversary of birth trauma. The impact on fathers and clinicians present at the traumatic birth is highlighted as secondary traumatic stress comes into play. Troubling glimpses of difficulties in mother–infant bonding are revealed.

  18. Tonopah Test Range closure sites revegetation plan

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.C.; Hall, D.B.

    1997-05-01

    This document is a revegetation plan for long-term stabilization (revegetation) of land disturbed by activities associated with the closure of a Bomblet Pit and the Five Points Landfill. Both sites are on the Tonopah Test Range (TTR) located in south-central Nevada. This document contains general reclamation practices and procedures that will be followed during the revegetation of these sites. The revegetation procedures proposed have been developed over several years of research and include the results of reclamation trials at Area 11 and Area 19 on the Nevada Test Site (NTS), and more recently at the Double Tracks (Nellis Air Force Range) reclamation demonstration plots. In addition, the results of reclamation efforts and concurrent research efforts at the Yucca Mountain Project have been considered in the preparation of this revegetation plan.

  19. Transfinite ranges and the local spectrum

    Czech Academy of Sciences Publication Activity Database

    Cho, M.; Harte, R.; Müller, Vladimír

    2013-01-01

    Roč. 398, č. 1 (2013), s. 403-408 ISSN 0022-247X R&D Projects: GA ČR GA201/09/0473; GA AV ČR IAA100190903 Institutional support: RVO:67985840 Keywords : transfinite ranges * Coeur algébrique * local spectrum Subject RIV: BA - General Mathematics Impact factor: 1.119, year: 2013 http://www.sciencedirect.com/science/article/pii/S0022247X12007081

  20. Long-range forecasting of intermittent streamflow

    OpenAIRE

    F. F. van Ogtrop; R. W. Vervoort; G. Z. Heller; D. M. Stasinopoulos; R. A. Rigby

    2011-01-01

    Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a statistical model to forecast streamflow up to 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS) to determine th...

  1. Long-range forecasting of intermittent streamflow

    OpenAIRE

    F. F. van Ogtrop; R. W. Vervoort; G. Z. Heller; D. M. Stasinopoulos; R. A. Rigby

    2011-01-01

    Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a probabilistic statistical model to forecast streamflow 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS) to determine the probabil...

  2. Ranges of bimodule projections and conditional expectations

    CERN Document Server

    Pluta, Robert

    2013-01-01

    The algebraic theory of corner subrings introduced by Lam (as an abstraction of the properties of Peirce corners eRe of a ring R associated with an idempotent e in R) is investigated here in the context of Banach and C*-algebras. We propose a general algebraic approach which includes the notion of ranges of (completely) contractive conditional expectations on C*-algebras and on ternary rings of operators, and we investigate when topological properties are consequences of the algebraic assumpt...

  3. FE-based long range ordered alloys

    International Nuclear Information System (INIS)

    Liu, C.-T.; Inouye, H.; Schaffhauser, A.C.

    1981-01-01

    Malleable long range ordered alloys having high critical ordering temperatures exist in the V(Co,Fe) 3 and V(Co,Fe,Ni) 3 system having a specified composition with an electron density no greater than 8.00. Excellent high temperature properties occur in alloys in this system, having specified compositions. The alloys are fabricable by casting, deforming and annealing for sufficient time to provide ordered structure. (author)

  4. Report to Congress on Sustainable Ranges

    Science.gov (United States)

    2014-02-01

    Chocolate Mountains Aerial Gunnery Range (CMAGR) which is a part of the Bob Stump Training Complex and is located in southern California. CMAGR is... industry (below 3 GHz) is heavily encumbered with existing users, including many military subscribers. Relocating these users to other portions of the...institutions, and industry to build on current agreements and allow for additional negotiated agreements as appropriate on the placement of sensors and

  5. Capacitive Proximity Sensor Has Longer Range

    Science.gov (United States)

    Vranish, John M.

    1992-01-01

    Capacitive proximity sensor on robot arm detects nearby object via capacitive effect of object on frequency of oscillator. Sensing element part of oscillator circuit operating at about 20 kHz. Total capacitance between sensing element and ground constitutes tuning capacitance of oscillator. Sensor circuit includes shield driven by replica of alternating voltage applied to sensing element. Driven shield concentrates sensing electrostatic field in exterior region to enhance sensitivity to object. Sensitivity and dynamic range has corresponding 12-to-1 improvement.

  6. Radio Frequency Ranging for Swarm Relative Localization

    Science.gov (United States)

    2017-10-01

    positioning, such as collision avoidance, formation flying, and patterned weapon delivery. Although there are many technologies that can be employed for...applications exist for relative positioning such as collision avoidance,3 formation flying,4 and patterned weapon delivery.5 In addition, relative...will be referred to as A1. A1 is designated to begin the ranging operations. After setup completes, the loop function continually executes until power

  7. Final Range Wide Environmental Impact Statement

    Science.gov (United States)

    2001-07-01

    government and missionary activities, by intertribal and interracial marriage , and by proximity to Yuma, AZ, which has grown rapidly in the past several...associated with the direct, indirect and cumulative effects of mission diversification and changes to land use for Yuma Proving Ground. Subject Terms...Range Wide Environmental Impact Statement presents the impacts associated with the direct, indirect, and cumulative effects of mission diversification

  8. Rapidly solidified long-range-ordered alloys

    International Nuclear Information System (INIS)

    Lee, E.H.; Koch, C.C.; Liu, C.T.

    1981-01-01

    The influence of rapid solidification processing on the microstructure of long-range-ordered alloys in the (Fe, Co, Ni) 3 V system has been studied by transmission electron microscopy. The main microstructural feature of the as-quenched alloys was a fine cell structure (approx. 300 nm diameter) decorated with carbide particles. This structure was maintained aftr annealing treatments which develop the ordered crystal structure. Other features of the microstructures both before and after annealing are presented and discussed. 6 figures

  9. OMV--Short Range Vehicle Concept

    Science.gov (United States)

    1986-01-01

    In this 1986 artist's concept, the Orbital Maneuvering Vehicle (OMV), is shown without its main propulsion module. Essentially two propulsion vehicles in one, the OMV could be powered by a main propulsion module , or, in its short range vehicle configuration shown here, use its own hydrazine and cold gas thrusters. As envisioned by Marshall Space Flight Center plarners, the OMV would be a remotely-controlled free-flying space tug which would place, rendezvous, dock, and retrieve orbital payloads.

  10. Short Rayleigh Range Free Electron Laser Amplifiers

    CERN Document Server

    Yu, L H; Murphy, J B; Rose, J; Shaftan, T V; Wang, X J; Watanabe, T

    2005-01-01

    An important requirement for a high average power laser system is a manageable power density on the first optical element. One possibility to achieve this is a single pass amplifier which generates a short Rayleigh range (SRL) light beam. We present design parameters and calculated performances for several SRL configurations. These include a simulation of the optically guided (pinched) MW class FEL [1], the scalloped beam FEL amplifier [2] and high gain TOK amplifiers we propose to explore at our SDL facility.

  11. Free range hens use the range more when the outdoor environment is enriched.

    Science.gov (United States)

    Nagle, T A D; Glatz, P C

    2012-04-01

    To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (prange (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly

  12. Does this range suit me? Range satisfaction of battery electric vehicle users.

    Science.gov (United States)

    Franke, Thomas; Günther, Madlen; Trantow, Maria; Krems, Josef F

    2017-11-01

    User satisfaction is a vital design criterion for sustainable systems. The present research aimed to understand factors relating to individually perceived range satisfaction of battery electric vehicle (BEV) users. Data from a large-scale BEV field trial (N = 72) were analyzed. Apart from an initial drop in range satisfaction, increasing practical experience was related to increased range satisfaction. Classical indicators of users' mobility profiles (daily travel distances) were only weakly related to lower range satisfaction (not significant), after controlling for practical experience and preferred coverage of mobility needs. The regularity/predictability of users' mobility patterns, the percentage of journeys not coverable because of range issues, and users' individual comfortable range accounted for variance in range satisfaction. Finally, range satisfaction was related to key indicators of general BEV acceptance (e.g., purchase intentions). These results underline the complex dynamics involved in individual range satisfaction, as well as its central role for BEV acceptance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Multi-stage origin of the Coast Range ophiolite, California: Implications for the life cycle of supra-subduction zone ophiolites

    Science.gov (United States)

    Shervais, J.W.; Kimbrough, D.L.; Renne, P.; Hanan, B.B.; Murchey, B.; Snow, C.A.; Zoglman, Schuman M.M.; Beaman, J.

    2004-01-01

    The Coast Range ophiolite of California is one of the most extensive ophiolite terranes in North America, extending over 700 km from the northernmost Sacramento Valley to the southern Transverse Ranges in central California. This ophiolite, and other ophiolite remnants with similar mid-Jurassic ages, represent a major but short-lived episode of oceanic crust formation that affected much of western North America. The history of this ophiolite is important for models of the tectonic evolution of western North America during the Mesozoic, and a range of conflicting interpretations have arisen. Current petrologic, geochemical, stratigraphic, and radiometric age data all favor the interpretation that the Coast Range ophiolite formed to a large extent by rapid extension in the forearc region of a nascent subduction zone. Closer inspection of these data, however, along with detailed studies of field relationships at several locales, show that formation of the ophiolite was more complex, and requires several stages of formation. Our work shows that exposures of the Coast Range ophiolite preserve evidence for four stages of magmatic development. The first three stages represent formation of the ophiolite above a nascent subduction zone. Rocks associated with the first stage include ophiolite layered gabbros, a sheeted complex, and volcanic rocks vith arc tholeiitic or (roore rarely) low-K calc-alkaline affinities. The second stage is characterized by intrusive wehrlite-clinopyroxenite complexes, intrusive gabbros, Cr-rich diorites, and volcanic rocks with high-Ca boninitic or tholeiitic ankaramite affinities. The third stage includes diorite and quartz diorite plutons, felsic dike and sill complexes, and calc-alkaline volcanic rocks. The first three stages of ophiolite formation were terminated by the intrusion of mid-ocean ridge basalt dikes, and the eruption of mid-ocean ridge basalt or ocean-island basalt volcanic suites. We interpret this final magmatic event (MORB

  14. Himalayan Mountain Range, India/China

    Science.gov (United States)

    1981-01-01

    The frontier between India (Kashmir) and China (Tibet) (33.5N, 79.5E) lies across the narrow land bridge between the two lakes near the center of this photo. Many of the peaks in this region of the Karakoram and Latakh ranges of the Himalayan Mountains, exceed 20,000 ft. making it one of the most remote regions of the Earth. The large end lake is the Kako in China and the long narrow lake is the Pangong in India.

  15. Tonopah Test Range 2030 Meeting Summary Report

    International Nuclear Information System (INIS)

    2009-01-01

    Corrective Action Sites (CASs) and Corrective Action Units (CAUs) at the Tonopah Test Range (TTR) may be placed into three categories: Closed, Closed in Place, or Closure in Progress. CASs and CAUs where contaminants were either not detected or were cleaned up to within regulatory action levels are summarized. CASs and CAUs where contaminants and/or waste have been closed in place are summarized. There is also a table that summarizes the contaminant that has been closed at each site, if land-use restrictions are present, and if post-closure inspections are required

  16. Volume dips; spot price ranges narrow

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This article is the September 1994 uranium market summary. Volume in the spot concentrates market fell below 1 million lbs U3O8. In total, twelve deals took place compared to 28 deals in August. Of the twelve deals, three took place in the spot concentrates market, two took place in the medium and long-term market, three in the conversion market, and four in the enrichment market. Restricted prices weakened, but unrestricted prices firmed slightly. The enrichment price range narrowed a bit

  17. Limited Range Sesame EOS for Ta

    Energy Technology Data Exchange (ETDEWEB)

    Greeff, Carl William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Crockett, Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rudin, Sven Peter [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Burakovsky, Leonid [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-30

    A new Sesame EOS table for Ta has been released for testing. It is a limited range table covering T ≤ 26, 000 K and ρ ≤ 37.53 g/cc. The EOS is based on earlier analysis using DFT phonon calculations to infer the cold pressure from the Hugoniot. The cold curve has been extended into compression using new DFT calculations. The present EOS covers expansion into the gas phase. It is a multi-phase EOS with distinct liquid and solid phases. A cold shear modulus table (431) is included. This is based on an analytic interpolation of DFT calculations.

  18. Development of wall ranging radiation inspection robot

    International Nuclear Information System (INIS)

    Lee, B. J.; Yoon, J. S.; Park, Y. S.; Hong, D. H.; Oh, S. C.; Jung, J. H.; Chae, K. S.

    1999-03-01

    With the aging of nation's nuclear facilities, the target of this project is to develop an under water wall ranging robotic vehicle which inspects the contamination level of the research reactor (TRIGA MARK III) as a preliminary process to dismantling. The developed vehicle is driven by five thrusters and consists of small sized control boards, and absolute position detector, and a radiation detector. Also, the algorithm for autonomous navigation is developed and its performance is tested through under water experiments. Also, the test result at the research reactor shows that the vehicle firmly attached the wall while measuring the contamination level of the wall

  19. Lunar laser ranging: the millimeter challenge

    International Nuclear Information System (INIS)

    Murphy, T W

    2013-01-01

    Lunar laser ranging has provided many of the best tests of gravitation since the first Apollo astronauts landed on the Moon. The march to higher precision continues to this day, now entering the millimeter regime, and promising continued improvement in scientific results. This review introduces key aspects of the technique, details the motivations, observables, and results for a variety of science objectives, summarizes the current state of the art, highlights new developments in the field, describes the modeling challenges, and looks to the future of the enterprise. (review article)

  20. Short-range interaction between hydrogen molecules

    Science.gov (United States)

    Mcmahan, A. K.; Beck, H.; Krumhansl, J. A.

    1974-01-01

    Recent calculations of the ground state energy of a system of four hydrogen atoms are reviewed with the aim of discerning the short-range repulsive part of the interaction potential between two hydrogen molecules. Extended-basis CI calculations which include a diffuse 2p orbital appear to be capable of determining the total interaction energy between to hydrogen molecules for any separation. Consistent results of such calculations suggest that the potential for intermolecular separations in the region from 1 to 2.5 A can now be specified to better than 10% with considerable confidence. Analytic fits to spherical averages of these results are presented.

  1. Fan-less long range alpha detector

    Science.gov (United States)

    MacArthur, Duncan W.; Bounds, John A.

    1994-01-01

    A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

  2. DC-DC converter with a wide load range and a wide input-voltage range

    NARCIS (Netherlands)

    Ting, Y.

    2015-01-01

    This thesis investigated the possibility of increasing the efficiency of a DC-DC converter over a wide load range and a wide input-voltage range based on the Single Active Bridge (SAB) topology with two approaches. The first approach involved making changes to the topology whereas the second made

  3. Population dynamics of sugar maple through the southern portion of its range: implications for range migration

    Science.gov (United States)

    Justin L. Hart; Christopher M. Oswalt; Craig M. Turberville

    2014-01-01

    The range of sugar maple (Acer saccharum Marsh.) is expected to shift northward in accord with changing climate. However, a pattern of increased sugar maple abundance has been reported from sites throughout the eastern US. The goal of our study was to examine the stability of the sugar maple southern range boundary by analyzing its demography through...

  4. Short-range/Long-range Integrated Target (SLIT) for Video Guidance Sensor Rendezvous and Docking

    Science.gov (United States)

    Roe, Fred D. (Inventor); Bryan, Thomas C. (Inventor)

    2009-01-01

    A laser target reflector assembly for mounting upon spacecraft having a long-range reflector array formed from a plurality of unfiltered light reflectors embedded in an array pattern upon a hemispherical reflector disposed upon a mounting plate. The reflector assembly also includes a short-range reflector array positioned upon the mounting body proximate to the long-range reflector array. The short-range reflector array includes three filtered light reflectors positioned upon extensions from the mounting body. The three filtered light reflectors retro-reflect substantially all incident light rays that are transmissive by their monochromatic filters and received by the three filtered light reflectors. In one embodiment the short-range reflector array is embedded within the hemispherical reflector,

  5. Hip strength and range of motion

    DEFF Research Database (Denmark)

    Mosler, Andrea B.; Crossley, Kay M.; Thorborg, Kristian

    2017-01-01

    Objectives To determine the normal profiles for hip strength and range of motion (ROM) in a professional football league in Qatar, and examine the effect of leg dominance, age, past history of injury, and ethnicity on these profiles. Design Cross-sectional cohort study. Methods Participants...... and external rotation in 90° flexion, hip IR in prone, bent knee fall out and hip abduction in side-lying. Demographic information was collected and the effect on the profiles was analysed using linear mixed models with repeated measures. Results Strength values (mean ± SD) were: adduction = 3.0 ± 0.6 Nm....../kg, abduction = 2.6 ± 0.4 Nm/kg, adduction/abduction ratio = 1.2 ± 0.2, Squeeze test = 3.6 ± 0.8 N/kg. Range of motion values: internal rotation in flexion = 32 ± 8°, external rotation = 38 ± 8°, internal rotation in prone = 38 ± 8°, bent knee fall out = 13 ± 4.4 cm, abduction in side-lying = 50 ± 7.3°. Leg...

  6. Perceptual Contrast Enhancement with Dynamic Range Adjustment.

    Science.gov (United States)

    Zhang, Hong; Li, Yuecheng; Chen, Hao; Yuan, Ding; Sun, Mingui

    2013-12-01

    Recent years, although great efforts have been made to improve its performance, few Histogram equalization (HE) methods take human visual perception (HVP) into account explicitly. The human visual system (HVS) is more sensitive to edges than brightness. This paper proposes to take use of this nature intuitively and develops a perceptual contrast enhancement approach with dynamic range adjustment through histogram modification. The use of perceptual contrast connects the image enhancement problem with the HVS. To pre-condition the input image before the HE procedure is implemented, a perceptual contrast map (PCM) is constructed based on the modified Difference of Gaussian (DOG) algorithm. As a result, the contrast of the image is sharpened and high frequency noise is suppressed. A modified Clipped Histogram Equalization (CHE) is also developed which improves visual quality by automatically detecting the dynamic range of the image with improved perceptual contrast. Experimental results show that the new HE algorithm outperforms several state-of-the-art algorithms in improving perceptual contrast and enhancing details. In addition, the new algorithm is simple to implement, making it suitable for real-time applications.

  7. Long range position and Orientation Tracking System

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L. [and others

    1996-02-01

    The long range Position and Orientation Tracking System is an active triangulation-based system that is being developed to track a target to a resolution of 6.35 mm (0.25 in.) and 0.009{degrees}(32.4 arcseconds) over a range of 13.72 m (45 ft.). The system update rate is currently set at 20 Hz but can be increased to 100 Hz or more. The tracking is accomplished by sweeping two pairs of orthogonal line lasers over infrared (IR) sensors spaced with known geometry with respect to one another on the target (the target being a rigid body attached to either a remote vehicle or a remote manipulator arm). The synchronization and data acquisition electronics correlates the time that an IR sensor has been hit by one of the four lasers and the angle of the respective mirror at the time of the hit. This information is combined with the known geometry of the IR sensors on the target to determine position and orientation of the target. This method has the advantage of allowing the target to be momentarily lost due to occlusions and then reacquired without having to return the target to a known reference point. The system also contains a camera with operator controlled lighting in each pod that allows the target to be continuously viewed from either pod, assuming their are no occlusions.

  8. A Formant Range Profile for Singers.

    Science.gov (United States)

    Titze, Ingo R; Maxfield, Lynn M; Walker, Megan C

    2017-05-01

    Vowel selection is important in differentiating between singing styles. The timbre of the vocal instrument, which is related to its frequency spectrum, is governed by both the glottal sound source and the vowel choices made by singers. Consequently, the ability to modify the vowel space is a measure of how successfully a singer can maintain a desired timbre across a range of pitches. Formant range profiles were produced as a means of quantifying this ability. Seventy-seven subjects (including trained and untrained vocalists) participated, producing vowels with three intended mouth shapes: (1) neutral or speech-like, (2) megaphone-shaped (wide open mouth), and (3) inverted-megaphone-shaped (widened oropharynx with moderate mouth opening). The first and second formant frequencies (F 1 and F 2 ) were estimated with fry phonation for each shape and values were plotted in F1-F2 space. By taking four vowels of a quadrangle /i, æ, a, u/, the resulting area was quantified in kHz 2 (kHz squared) as a measure of the subject's ability to modify their vocal tract for spectral differences. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  9. Mitochondrial uncouplers with an extraordinary dynamic range.

    Science.gov (United States)

    Lou, Phing-How; Hansen, Birgit S; Olsen, Preben H; Tullin, Søren; Murphy, Michael P; Brand, Martin D

    2007-10-01

    We have discovered that some weak uncouplers (typified by butylated hydroxytoluene) have a dynamic range of more than 10(6) in vitro: the concentration giving measurable uncoupling is less than one millionth of the concentration causing full uncoupling. They achieve this through a high-affinity interaction with the mitochondrial adenine nucleotide translocase that causes significant but limited uncoupling at extremely low uncoupler concentrations, together with more conventional uncoupling at much higher concentrations. Uncoupling at the translocase is not by a conventional weak acid/anion cycling mechanism since it is also caused by substituted triphenylphosphonium molecules, which are not anionic and cannot protonate. Covalent attachment of the uncoupler to a mitochondrially targeted hydrophobic cation sensitizes it to membrane potential, giving a small additional effect. The wide dynamic range of these uncouplers in isolated mitochondria and intact cells reveals a novel allosteric activation of proton transport through the adenine nucleotide translocase and provides a promising starting point for designing safer uncouplers for obesity therapy.

  10. Tectonochemistry of the Brooks Range Ophiolite, Alaska

    Science.gov (United States)

    Biasi, J.; Asimow, P. D.; Harris, R. A.

    2017-12-01

    The Brooks Range Ophiolite (BRO), recently estimated to be 1800km2 in area, is the largest ophiolite in the Western Hemisphere. However, due to its remote location, it remains one of the least studied. Mineral exploration and reconnaissance-level mapping of the ophiolite were done in the 1970s and 1980s. Some chemical analyses were also performed, but since that time the BRO has received little attention. Over the subsequent 25+ years, the study of ophiolites has advanced greatly. These early studies found that the BRO lies in the structurally highest position in the Brooks Range, and its obduction probably coincided with the collision between the Koyukuk Arc and the Arctic-Alaska continental margin. It is therefore important to determine the tectonic setting in which the BRO formed if one wants to understand the tectonic history of the Northern Cordillera during the Jurassic/Cretaceous. Here we present new tectonochemistry data from the BRO. This includes whole-rock data (via XRF), trace element data (via XRF and ICP-MS), and mineral chemistries (via Electron Microprobe). Using immobile element fingerprinting, we constrain the tectonic setting in which the BRO formed and how this information ties in with other events in the Northern Cordillera's history. The fingerprinting results are supplemented by Cr-in-spinel data and Al-in-olivine thermometry.

  11. 8-Channel Broadband Laser Ranging Hardware Development

    Science.gov (United States)

    Bennett, Corey; La Lone, Brandon; Younk, Patrick; Daykin, Ed; Rhodes, Michelle; Perry, Daniel; Tran, Vu; Miller, Edward

    2017-06-01

    Broadband Laser Ranging (BLR) is a new diagnostic being developed to precisely measure the position vs. time of surfaces, shock break out, particle clouds, jets, and debris moving at kilometers per second speeds. The instrument uses interferometry to encode distance into a modulation in the spectrum of pulses from a mode-locked fiber laser and uses a dispersive Fourier transformation to map the spectral modulation into time. Range information is thereby recorded on a fast oscilloscope at the repetition rate of the laser, approximately every 50 ns. Current R&D is focused on developing a compact 8-channel system utilizing one laser and one high-speed oscilloscope. This talk will emphasize the hardware being developed for applications at the Contained Firing Facility at LLNL, but has a common architecture being developed in collaboration with NSTec and LANL for applications at multiple other facilities. Prepared by LLNL under Contract DE-AC52-07NA27344, by LANL under Contract DE-AC52-06NA25396, and by NSTec Contract DE-AC52-06NA25946.

  12. Photonic limiters with enhanced dynamic range

    Science.gov (United States)

    Kononchuk, Rodion; Limberopoulos, Nicholaos; Anisimov, Igor; Vitebskiy, Ilya; Chabanov, Andrey

    2018-02-01

    Optical limiters transmit low intensity input light while blocking input light with the intensity exceeding certain limiting threshold. Conventional passive limiters utilize nonlinear optical materials, which are transparent at low light intensity and turn absorptive at high intensity. Strong nonlinear absorption, though, can result in over- heating and destruction of the limiter. Another problem is that the limiting threshold provided by the available optical material with nonlinear absorption is too high for many applications. To address the above problems, the nonlinear material can be incorporated in a photonic structure with engineered dispersion. At low intensity, the photonic structure can display resonant transmission via localized mode(s), while at high intensity the resonant transmission can disappear, and the entire stack can become highly re ective (not absorptive) within a broad frequency range. In the proposed design, the transition from the resonant transmission at low intensity to nearly total re ectivity at high intensity does not rely on nonlinear absorption; instead, it requires only a modest change in the refractive index of the nonlinear material. The latter implies a dramatic increase in the dynamic range of the limiter. The main idea is to eliminate the high-intensity resonant transmission by decoupling the localized (resonant) modes from the input light, rather than suppressing those modes using nonlinear absorption. Similar approach can be used for light modulation and switching.

  13. Climate-driven range extension of Amphistegina (protista, foraminiferida): models of current and predicted future ranges.

    Science.gov (United States)

    Langer, Martin R; Weinmann, Anna E; Lötters, Stefan; Bernhard, Joan M; Rödder, Dennis

    2013-01-01

    Species-range expansions are a predicted and realized consequence of global climate change. Climate warming and the poleward widening of the tropical belt have induced range shifts in a variety of marine and terrestrial species. Range expansions may have broad implications on native biota and ecosystem functioning as shifting species may perturb recipient communities. Larger symbiont-bearing foraminifera constitute ubiquitous and prominent components of shallow water ecosystems, and range shifts of these important protists are likely to trigger changes in ecosystem functioning. We have used historical and newly acquired occurrence records to compute current range shifts of Amphistegina spp., a larger symbiont-bearing foraminifera, along the eastern coastline of Africa and compare them to analogous range shifts currently observed in the Mediterranean Sea. The study provides new evidence that amphisteginid foraminifera are rapidly progressing southwestward, closely approaching Port Edward (South Africa) at 31°S. To project future species distributions, we applied a species distribution model (SDM) based on ecological niche constraints of current distribution ranges. Our model indicates that further warming is likely to cause a continued range extension, and predicts dispersal along nearly the entire southeastern coast of Africa. The average rates of amphisteginid range shift were computed between 8 and 2.7 km year(-1), and are projected to lead to a total southward range expansion of 267 km, or 2.4° latitude, in the year 2100. Our results corroborate findings from the fossil record that some larger symbiont-bearing foraminifera cope well with rising water temperatures and are beneficiaries of global climate change.

  14. Climate-driven range extension of Amphistegina (protista, foraminiferida: models of current and predicted future ranges.

    Directory of Open Access Journals (Sweden)

    Martin R Langer

    Full Text Available Species-range expansions are a predicted and realized consequence of global climate change. Climate warming and the poleward widening of the tropical belt have induced range shifts in a variety of marine and terrestrial species. Range expansions may have broad implications on native biota and ecosystem functioning as shifting species may perturb recipient communities. Larger symbiont-bearing foraminifera constitute ubiquitous and prominent components of shallow water ecosystems, and range shifts of these important protists are likely to trigger changes in ecosystem functioning. We have used historical and newly acquired occurrence records to compute current range shifts of Amphistegina spp., a larger symbiont-bearing foraminifera, along the eastern coastline of Africa and compare them to analogous range shifts currently observed in the Mediterranean Sea. The study provides new evidence that amphisteginid foraminifera are rapidly progressing southwestward, closely approaching Port Edward (South Africa at 31°S. To project future species distributions, we applied a species distribution model (SDM based on ecological niche constraints of current distribution ranges. Our model indicates that further warming is likely to cause a continued range extension, and predicts dispersal along nearly the entire southeastern coast of Africa. The average rates of amphisteginid range shift were computed between 8 and 2.7 km year(-1, and are projected to lead to a total southward range expansion of 267 km, or 2.4° latitude, in the year 2100. Our results corroborate findings from the fossil record that some larger symbiont-bearing foraminifera cope well with rising water temperatures and are beneficiaries of global climate change.

  15. Spatial Cognition and Range Use in Free-Range Laying Hens

    Science.gov (United States)

    Campbell, Dana L. M.; Loh, Ziyang A.; Dyall, Tim R.; Lee, Caroline

    2018-01-01

    Simple Summary Individual free-range laying hens vary in their use of the outdoor range. The outdoor environment is typically more complex and variable than indoor housing and thus range use may be related to differences in spatial abilities. Individual adult hens that never went outside were slower to learn a T-maze task—which requires birds to repeatedly find a food reward in one arm of the maze, compared to outdoor-preferring hens. Pullets that were faster to learn the maze also showed more visits to the range in their first month of range access but only in one of two tested groups. Early enrichment improved learning of the maze but only when the birds were tested before onset of lay. Fear may play a role in inhibiting bird’s spatial learning and their range use. More studies of different enriched rearing treatments and their impacts on fear and learning would be needed to confirm these findings. Overall, these results contribute to our understanding of why some birds choose to never access the outdoor range area. Abstract Radio-frequency identification tracking shows individual free-range laying hens vary in range use, with some never going outdoors. The range is typically more environmentally complex, requiring navigation to return to the indoor resources. Outdoor-preferring hens may have improved spatial abilities compared to indoor-preferring hens. Experiment 1 tested 32 adult ISA Brown hens in a T-maze learning task that showed exclusively-indoor birds were slowest to reach the learning success criterion (p birds reached learning success criterion faster at 15–16 weeks (p 0.05), the age that coincided with the onset of lay. Enriched birds that were faster to learn the maze task showed more range visits in the first 4 weeks of range access. Enriched and non-enriched birds showed no differences in telencephalon or hippocampal volume (p > 0.05). Fear may reduce spatial abilities but further testing with more pen replicates per early rearing treatments

  16. Free Range Hens Use the Range More When the Outdoor Environment Is Enriched

    Directory of Open Access Journals (Sweden)

    T. A. D. Nagle

    2012-04-01

    Full Text Available To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown. Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000–6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07 for more hens to be in the paddock. When forage was provided in paddocks more control birds (55% were observed in the range in morning than in the afternoon (30% while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05 higher % of birds in the range (43% vs. 24% and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt

  17. Home ranges, habitat and body mass: simple correlates of home range size in ungulates.

    Science.gov (United States)

    Ofstad, Endre Grüner; Herfindal, Ivar; Solberg, Erling Johan; Sæther, Bernt-Erik

    2016-12-28

    The spatial scale of animal space use, e.g. measured as individual home range size, is a key trait with important implications for ecological and evolutionary processes as well as management and conservation of populations and ecosystems. Explaining variation in home range size has therefore received great attention in ecological research. However, few studies have examined multiple hypotheses simultaneously, which is important provided the complex interactions between life history, social system and behaviour. Here, we review previous studies on home range size in ungulates, supplementing with a meta-analysis, to assess how differences in habitat use and species characteristics affect the relationship between body mass and home range size. Habitat type was the main factor explaining interspecific differences in home range size after accounting for species body mass and group size. Species using open habitats had larger home ranges for a given body mass than species using closed habitats, whereas species in open habitats showed a much weaker allometric relationship compared with species living in closed habitats. We found no support for relationships between home range size and species diet or mating system, or any sexual differences. These patterns suggest that the spatial scale of animal movement mainly is a combined effect of body mass, group size and the landscape structure. Accordingly, landscape management must acknowledge the influence of spatial distribution of habitat types on animal behaviour to ensure natural processes affecting demography and viability of ungulate populations. © 2016 The Author(s).

  18. Climate driven range divergence among host species affects range-wide patterns of parasitism

    Directory of Open Access Journals (Sweden)

    Richard E. Feldman

    2017-01-01

    Full Text Available Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose and Rangifer tarandus (caribou, in North America. We used MaxEnt models to predict the recent (2000 and future (2050 ranges (probabilities of occurrence of the cervids and a parasite Parelaphostrongylus tenuis (brainworm taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces/R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces/R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces/R. tarandus are likely to decline, but minimal spatial overlap where A. alces/R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.

  19. Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

    International Nuclear Information System (INIS)

    Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min

    2015-01-01

    In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments

  20. Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments.

  1. Unsynchronized scanning with a low-cost laser range finder for real-time range imaging

    Science.gov (United States)

    Hatipoglu, Isa; Nakhmani, Arie

    2017-06-01

    Range imaging plays an essential role in many fields: 3D modeling, robotics, heritage, agriculture, forestry, reverse engineering. One of the most popular range-measuring technologies is laser scanner due to its several advantages: long range, high precision, real-time measurement capabilities, and no dependence on lighting conditions. However, laser scanners are very costly. Their high cost prevents widespread use in applications. Due to the latest developments in technology, now, low-cost, reliable, faster, and light-weight 1D laser range finders (LRFs) are available. A low-cost 1D LRF with a scanning mechanism, providing the ability of laser beam steering for additional dimensions, enables to capture a depth map. In this work, we present an unsynchronized scanning with a low-cost LRF to decrease scanning period and reduce vibrations caused by stop-scan in synchronized scanning. Moreover, we developed an algorithm for alignment of unsynchronized raw data and proposed range image post-processing framework. The proposed technique enables to have a range imaging system for a fraction of the price of its counterparts. The results prove that the proposed method can fulfill the need for a low-cost laser scanning for range imaging for static environments because the most significant limitation of the method is the scanning period which is about 2 minutes for 55,000 range points (resolution of 250x220 image). In contrast, scanning the same image takes around 4 minutes in synchronized scanning. Once faster, longer range, and narrow beam LRFs are available, the methods proposed in this work can produce better results.

  2. Allee dynamics: Growth, extinction and range expansion

    Science.gov (United States)

    Bose, Indrani; Pal, Mainak; Karmakar, Chiranjit

    In population biology, the Allee dynamics refer to negative growth rates below a critical population density. In this paper, we study a reaction-diffusion (RD) model of popoulation growth and dispersion in one dimension, which incorporates the Allee effect in both the growth and mortatility rates. In the absence of diffusion, the bifurcation diagram displays regions of both finite population density and zero population density, i.e. extinction. The early signatures of the transition to extinction at the bifurcation point are computed in the presence of additive noise. For the full RD model, the existence of traveling wave solutions of the population density is demonstrated. The parameter regimes in which the traveling wave advances (range expansion) and retreats are identified. In the weak Allee regime, the transition from the pushed to the pulled wave is shown as a function of the mortality rate constant. The results obtained are in agreement with the recent experimental observations on budding yeast populations.

  3. An introduction to optimal satellite range scheduling

    CERN Document Server

    Vázquez Álvarez, Antonio José

    2015-01-01

    The satellite range scheduling (SRS) problem, an important operations research problem in the aerospace industry consisting of allocating tasks among satellites and Earth-bound objects, is examined in this book. SRS principles and solutions are applicable to many areas, including: Satellite communications, where tasks are communication intervals between sets of satellites and ground stations Earth observation, where tasks are observations of spots on the Earth by satellites Sensor scheduling, where tasks are observations of satellites by sensors on the Earth. This self-contained monograph begins with a structured compendium of the problem and moves on to explain the optimal approach to the solution, which includes aspects from graph theory, set theory, game theory and belief networks. This book is accessible to students, professionals and researchers in a variety of fields, including: operations research, optimization, scheduling theory, dynamic programming and game theory. Taking account of the distributed, ...

  4. Long-range interaction of anisotropic systems

    KAUST Repository

    Zhang, Junyi

    2015-02-01

    The first-order electrostatic interaction energy between two far-apart anisotropic atoms depends not only on the distance between them but also on their relative orientation, according to Rayleigh-Schrödinger perturbation theory. Using the first-order interaction energy and the continuum model, we study the long-range interaction between a pair of parallel pristine graphene sheets at zero temperature. The asymptotic form of the obtained potential density, &epsi:(D) &prop: ?D ?3 ?O(D?4), is consistent with the random phase approximation and Lifshitz theory. Accordingly, neglectance of the anisotropy, especially the nonzero first-order interaction energy, is the reason why the widely used Lennard-Jones potential approach and dispersion corrections in density functional theory give a wrong asymptotic form ε(D) &prop: ?D?4. © EPLA, 2015.

  5. Broader range of skills distinguishes successful CFOs.

    Science.gov (United States)

    Doody, M F

    2000-09-01

    In recent years, healthcare CFOs have seen their role expand significantly beyond traditional financial duties. A series of trended surveys on CFO roles and responsibilities reveals that today's healthcare CFO requires a broad new range of traits and skills in the areas of leadership, operations, and healthcare strategy. CFOs regard strategic thinking and the ability to communicate clearly as the most important of their essential leadership traits and skills, respectively. Among operational and strategic skills, CFOs most often cite the importance of being able to improve organizational performance and benchmark. Healthcare CFOs can enhance their chances of success by focusing self-improvement efforts on five key areas: implementing the organization's vision; developing tactics that stimulate change; enhancing communication skills; focusing on managing and leading; and strengthening relationships.

  6. Range-preserving AE(0-spaces

    Directory of Open Access Journals (Sweden)

    W.W. Comfort

    2013-07-01

    Full Text Available All spaces here are Tychonoff spaces. The class AE(0 consists of those spaces which are absolute extensors for compact zero-dimensional spaces. We define and study here the subclass AE(0rp, consisting of those spaces for which extensions of continuous functions can be chosen to have the same range. We prove these results. If each point of T 2 AE(0 is a G-point of T , then T 2 AE(0rp. These are equivalent: (a T 2 AE(0rp; (b every compact subspace of T is metrizable; (c every compact subspace of T is dyadic; and (d every subspace of T is AE(0. Thus in particular, every metrizable space is an AE(0rp-space.

  7. Optimal short range trajectories for helicopters

    Science.gov (United States)

    Slater, G. L.; Erzberger, H.

    1983-01-01

    An optimal flight path algorithm using a simplified altitude state model and an apriori climb-cruise-descent flight profile has been developed and applied to determine minimum fuel and minimum cost trajectories for a helicopter flying a fixed range trajectory. The performance model is based on standard flight manual data and is such that on-line trajectory optimization is feasible with a relatively small computer. The results show that the optimal flight path and optimal cruise altitude can represent a 10 percent fuel saving on a minimum fuel trajectory. The optimal trajectories show considerable variability due to helicopter weight, ambient winds and the relative cost trade-off between time and fuel. In general, 'reasonable' variations from the optimal velocities and cruise altitudes do not significantly degrade the optimal cost.

  8. Mappings with closed range and compactness

    International Nuclear Information System (INIS)

    Iyahen, S.O.; Umweni, I.

    1985-12-01

    The motivation for this note is the result of E.O. Thorp that a normed linear space E is finite dimensional if and only if every continuous linear map for E into any normed linear space has a closed range. Here, a class of Hausdorff topological groups is introduced; called r-compactifiable topological groups, they include compact groups, locally compact Abelian groups and locally convex linear topological spaces. It is proved that a group in this class which is separable, complete metrizable or locally compact, is necessarily compact if its image by a continuous group homomorphism is necessarily closed. It is deduced then that a Hausdorff locally convex is zero if its image by a continuous additive map is necessarily closed. (author)

  9. An extended range neutron rem counter

    International Nuclear Information System (INIS)

    Birattari, C.; Nuccetelli, C.; Pelliccioni, M.; Silari, M.

    1990-01-01

    Extensive Monte Carlo calculations have been carried out to assess the possibility of extending the sensitivity of a neutron rem counter of the Andersson-Braun type up to several hundred MeV. The validity of the model adopted has first been checked by comparing with experimental data the calculated response curve and the angular dependence of the sensitivity for a well known commercial rem counter. Next, a number of modifications to the configuration of the moderator-attenuator have been investigated. The response functions and angular distributions produced by two simple solutions yielding an instrument with a sensitivity extended up to 400 MeV are presented. The response of the original rem counter and of its two modified versions to nine test spectra has also been calculated. The resulting instrument is transportable rather than portable, but the availability of an extended range neutron survey meter would be of great advantage at medium and high energy particle accelerator facilities. (orig.)

  10. Infinite-range quantum random Heisenberg magnet

    Science.gov (United States)

    Arrachea, Liliana; Rozenberg, Marcelo J.

    2002-06-01

    We study with exact diagonalization techniques the Heisenberg model for a system of SU(2) spins with S=1/2 and random infinite-range exchange interactions. We calculate the critical temperature Tg for the spin-glass to paramagnetic transition. We obtain Tg~0.13, in good agreement with previous quantum Monte Carlo and analytical estimates. We provide a detailed picture for the different kind of excitations which intervene in the dynamical response χ''(ω,T) at T=0 and analyze their evolution as T increases. We also calculate the specific heat Cv(T). We find that it displays a smooth maximum at TM~0.25, in good qualitative agreement with experiments. We argue that the fact that TM>Tg is due to a quantum disorder effect.

  11. Range of drainage effect of surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Sozanski, J.

    1978-03-01

    This paper discusses methods of calculating the range of effects of water drainage from surface coal mines and other surface mines. It is suggested that methods based on test pumping (water drainage) are time consuming, and the results can be distorted by atmospheric factors such as rain fall or dry period. So-called empirical formulae produce results which are often incorrect. The size of a cone shaped depression calculated on the basis of empirical formulae can be ten times smaller than the size of the real depression. It is suggested that using a formula based on the Dupuit formula is superior to other methods of depression calculation. According to the derived formulae the radius of the depresion cone is a function of parameters of the water bearing horizons, size of surface mine working and of water depression. The proposed formula also takes into account the influence of atmospheric factors (water influx caused by precipitation, etc.). (1 ref.) (In Polish)

  12. Characterizing short-range vs. long-range spatial correlations in dislocation distributions

    Energy Technology Data Exchange (ETDEWEB)

    Chevy, Juliette, E-mail: juliette.chevy@gmail.com [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)] [Laboratoire Science et Ingenierie des Materiaux et Procedes, Grenoble INP-CNRS-UJF, BP 75, 38402 St. Martin d' Heres Cedex (France); Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent [Laboratoire de Physique et Mecanique des Materiaux, Universite Paul Verlaine-Metz/CNRS, Ile du Saulcy, 57045 Metz Cedex (France); Bastie, Pierre [Laboratoire de Spectrometrie Physique, BP 87, 38402 St. Martin d' Heres Cedex (France)] [Institut Laue Langevin, BP 156, 38042 Grenoble Cedex 9 (France); Duval, Paul [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)

    2010-03-15

    Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

  13. Characterizing short-range vs. long-range spatial correlations in dislocation distributions

    International Nuclear Information System (INIS)

    Chevy, Juliette; Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent; Bastie, Pierre; Duval, Paul

    2010-01-01

    Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

  14. Satellite-to-satellite orbit determination using minimum, discrete range and range-rate data only

    Science.gov (United States)

    Culp, R. D.; Chow, C. C.

    1984-08-01

    An observer satellite in a known orbit makes discrete measurement of the range and range-rate of an unknown satellite. If, at every observation, both range and range-rate are measured simutaneously, then three such observations are theoretically sufficient to determine the orbit of the unknown satellite. Techniques for achieving orbit determination from this minimum data are of interest, and are considered here. It is investigated by solving a set of nonlinear algebraic equations with a modified Newton's method. The method is applied to four typical preliminary orbit determination problems. The effect of total observation time interval on the precision of this method is examined. Rules for constructing initial guesses that significantly reduce computation and improve the probability of convergence to the true solution are presented. It will be shown that the method exhibits fast convergence even with poor initial guesses. Numerical examples show that excellent precision of resulting solution can be obtained.

  15. Tonopah Test Range Post-Closure Inspection Annual Report, Tonopah Test Range, Nevada, Calendar Year 2003

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Bechtel Nevada

    2004-04-01

    This post-closure inspection report provides documentation of the semiannual inspection activities, maintenance and repair activities, and conclusions and recommendations for calendar year 2003 for eight corrective action units located on the Tonopah Test Range, Nevada.

  16. Short range, ultra-wideband radar with high resolution swept range gate

    Science.gov (United States)

    McEwan, Thomas E.

    1998-05-26

    A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control.

  17. Range resolved lidar for long distance ranging with sub-millimeter resolution.

    Science.gov (United States)

    Piracha, Mohammad Umar; Nguyen, Dat; Mandridis, Dimitrios; Yilmaz, Tolga; Ozdur, Ibrahim; Ozharar, Sarper; Delfyett, Peter J

    2010-03-29

    A lidar technique employing temporally stretched, frequency chirped pulses from a 20 MHz mode locked laser is presented. Sub-millimeter resolution at a target range of 10.1 km (in fiber) is observed. A pulse tagging scheme based on phase modulation is demonstrated for range resolved measurements. A carrier to noise ratio of 30 dB is observed at an unambiguous target distance of 30 meters in fiber.

  18. In-Body Ranging with Ultra-Wideband Signals: Techniques and Modeling of the Ranging Error

    Directory of Open Access Journals (Sweden)

    Muzaffer Kanaan

    2017-01-01

    Full Text Available Results about the problem of accurate ranging within the human body using ultra-wideband signals are shown. The ability to accurately measure the range between a sensor implanted in the human body and an external receiver can make a number of new medical applications such as better wireless capsule endoscopy, next-generation microrobotic surgery systems, and targeted drug delivery systems possible. The contributions of this paper are twofold. First, we propose two novel range estimators: one based on an implementation of the so-called CLEAN algorithm for estimating channel profiles and another based on neural networks. Second, we develop models to describe the statistics of the ranging error for both types of estimators. Such models are important for the design and performance analysis of localization systems. It is shown that the ranging error in both cases follows a heavy-tail distribution known as the Generalized Extreme Value distribution. Our results also indicate that the estimator based on neural networks outperforms the CLEAN-based estimator, providing ranging errors better than or equal to 3.23 mm with 90% probability.

  19. U-Pb zircon and 40Ar/39Ar geochronology of sericite from hydrothermal alteration zones: new constraints for the timing of Ediacaran gold mineralization in the Sukhaybarat area, western Afif terrane, Saudi Arabia

    Science.gov (United States)

    Harbi, Hesham M.; Ali, Kamal A.; McNaughton, Neal J.; Andresen, Arild

    2017-07-01

    The Sukhaybarat East and Red Hill deposits, in the northeastern part of the Arabian Shield, are mesothermal vein-type gold deposits hosted by late Cryogenian-Ediacaran intrusive rocks of the Idah suites (diorite, tonalite, granodiorite) and, at Sukhaybarat East, also by Ediacaran metasedimentary rocks. Gold mineralization comprises quartz-arsenopyrite veins (Sukhaybarat East), quartz-carbonate-pyrite veins (Red Hill), and subordinate gold-base metal sulfide veins. In the Red Hill deposit, alteration is complicated due to multiple overprinting hydrothermal events and is characteristically affected by pervasive, pink quartz-K-feldspar-hematite alteration which is overprinted by potassic alteration characterized by a quartz-biotite-carbonate-muscovite/sericite-rutile-apatite assemblage. This assemblage is associated with molybdenite veins which appear to form late in the paragenetic sequence and may represent either evolution of the ore fluid composition, or a later, unrelated mineralized fluids. Hydrothermal alteration at the Sukhaybarat East deposit is dominated by quartz-carbonate-sericite-arsenopyrite assemblages. Zircon from ore-hosting tonalite at Sukhaybarat East yields a U-Pb age of 629 ± 6 Ma, and biotite from the same rock gives an 40Ar/39Ar age of 622 ± 23 Ma. The 40Ar/39Ar age is within the uncertainty range for the U-Pb age of the host intrusion and is interpreted as a minimally disturbed cooling age for the tonalite. In the Red Hill area, granodiorite was emplaced at 615 ± 5 Ma, whereas muscovite/sericite separated from a mineralized sample of a quartz-carbonate-pyrite vein, that was overprinted by molybdenite-bearing veinlets, yields an 40Ar/39Ar age of 597 ± 8 Ma. We interpreted this age to represent the maximum age of the molybdenite mineralization and the probable minimum age of gold mineralization in the Red Hill deposit.

  20. Relativistic tests with lunar laser ranging

    Science.gov (United States)

    Hofmann, F.; Müller, J.

    2018-02-01

    This paper presents the recent version of the lunar laser ranging (LLR) analysis model at the Institut für Erdmessung (IfE), Leibniz Universität Hannover and highlights a few tests of Einstein’s theory of gravitation using LLR data. Investigations related to a possible temporal variation of the gravitational constant, the equivalence principle, the PPN parameters β and γ as well as the geodetic precession were carried out. The LLR analysis model was updated by gravitational effects of the Sun and planets with the Moon as extended body. The higher-order gravitational interaction between Earth and Moon as well as effects of the solid Earth tides on the lunar motion were refined. The basis for the modeled lunar rotation is now a 2-layer core/mantle model according to the DE430 ephemeris. The validity of Einstein’s theory was studied using this updated analysis model and an LLR data set from 1970 to January 2015. Within the estimated accuracies, no deviations from Einstein’s theory are detected. A relative temporal variation of the gravitational constant is estimated as \\dot{G}/G_0=(7.1+/-7.6)×10-14~yr-1 , the test of the equivalence principle gives Δ(m_g/m_i)EM=(-3+/-5)×10-14 and the Nordtvedt parameter \

  1. Long-range forecasting of intermittent streamflow

    Science.gov (United States)

    van Ogtrop, F. F.; Vervoort, R. W.; Heller, G. Z.; Stasinopoulos, D. M.; Rigby, R. A.

    2011-11-01

    Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a statistical model to forecast streamflow up to 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS) to determine the probability of flow occurring in any of the systems. We then use the same regression framework in combination with a right-skewed distribution, the Box-Cox t distribution, to model the intensity (depth) of the non-zero streamflows. Time, seasonality and climate indices, describing the Pacific and Indian Ocean sea surface temperatures, are tested as covariates in the GAMLSS model to make probabilistic 6 and 12-month forecasts of the occurrence and intensity of streamflow. The output reveals that in the study region the occurrence and variability of flow is driven by sea surface temperatures and therefore forecasts can be made with some skill.

  2. Long-range forecasting of intermittent streamflow

    Directory of Open Access Journals (Sweden)

    F. F. van Ogtrop

    2011-11-01

    Full Text Available Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a statistical model to forecast streamflow up to 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS to determine the probability of flow occurring in any of the systems. We then use the same regression framework in combination with a right-skewed distribution, the Box-Cox t distribution, to model the intensity (depth of the non-zero streamflows. Time, seasonality and climate indices, describing the Pacific and Indian Ocean sea surface temperatures, are tested as covariates in the GAMLSS model to make probabilistic 6 and 12-month forecasts of the occurrence and intensity of streamflow. The output reveals that in the study region the occurrence and variability of flow is driven by sea surface temperatures and therefore forecasts can be made with some skill.

  3. Long range position and orientation tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L.; Bernacki, B.E.; Nypaver, D.J.

    1995-12-31

    The long range position and orientation tracking system (LRPOTS) will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the man-ways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the Content Mobilization System (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation.

  4. The normal range of condylar movement

    International Nuclear Information System (INIS)

    Choe, Han Up; Park, Tae Won

    1978-01-01

    The purpose of this study was to investigate the normal range of condylar movement of normal adults. The author gas observed roentgenographic images of four serial positions of condylar head taken by modified transcranial lateral oblique projection. The serial positions are centric occlusion, rest position, 1 inch open position and maximal open position. The results were obtained as follow; 1. Inter-incisal distance was 46.85 mm in maximal open position. 2. The length between the deepest point of glenoid fossa and summit of condylar head in rest position was wider than that in centric occlusion by 0.8 mm. 3. In 1 inch open position, condylar head moved forward from the standard line in 12.64 mm of horizontal direction and moved downwards from the standard line in 1.84 mm of vertical direction. 4. In maximal open position, condylar head moved forward from the standard line in 19.06 mm of horizontal direction and moved downwards from the standard line in 0.4 mm of vertical direction. 5. In centric occlusion, the width between glenoid fossa and margin of condylar head was greater in the posterior portion than in the anterior portion by 0.4 mm. 6. Except for estimated figures of 1 inch open position, all of the estimated figures was greater in male than in female.

  5. Long-range Rocky Flats utilization study

    International Nuclear Information System (INIS)

    1983-02-01

    The purpose of this Study was to provide information concerning the Rocky Flats Plant and its operations that will be useful to the Nation's decision-makers in determining the long-range future of the Plant. This Study was conducted under the premise that national defense policy must be supported and, accordingly, the capabilities at Rocky Flats must be maintained there or at some other location(s). The Study, therefore, makes no attempt to speculate on how possible future changes in national defense policy might affect decisions regarding the utilization of Rocky Flats. Factors pertinent to decisions regarding Rocky Flats, which are included in the Study, are: physical condition of the Plant and its vulnerabilities to natural phenomena; risks associated with plutonium to Plant workers and the public posed by postulated natural phenomena and operational accidents; identification of alternative actions regarding the future use of the Rocky Flats Plant with associated costs and time scales; local socioeconomic impacts if Rocky Flats operations were relocated; and potential for other uses if Rocky Flats facilities were vacated. The results of the tasks performed in support of this Study are summarized in the context of these five factors

  6. Shakedown and ratchetting below the creep range

    International Nuclear Information System (INIS)

    Ponter, A.R.S.

    1983-01-01

    The report reviews current understanding of the behaviour of structure subject to variable mechanical and thermal loading below the creep range through a comparison of theoretical solutions and experimental studies. The particular characteristics of the austenitic stainless steels are emphasized in components subject to moderate primary loads and large thermal loads. The review shows that a clear classification of types of thermal loading is required in design. Two main classes, termed category A and B, exist which arise not from the magnitude of the thermal stresses but their extent through the material volume of the structure. In category A situations, the Bree plate problem being the prime example, the maximum thermal stresses occur over a volume of the structure which does not contain a mechanism of failure. As a result very large thermal stresses may be withstood without ratchetting occurring for sufficiently small mechanical loads. For category B situations, the maximum thermal stress occur within a volume of material which contains a mechanism of deformation. In such cases, the capacity of the structure to withstand thermal loading is limited by a variation of the maximum thermal stress at a material point of 2σsub(γ) where σsub(γ) is a suitably defined yield stress. This situation seems to be the most typical problem of the Liquid Metal Fast Reactor and the ''3Sm'' limit in the ASME III code restriction on secondary stress cannot be exceeded if ratchetting is to be prevented

  7. Long range position and orientation tracking system

    International Nuclear Information System (INIS)

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L.; Bernacki, B.E.; Nypaver, D.J.

    1995-01-01

    The long range position and orientation tracking system (LRPOTS) will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the man-ways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the Content Mobilization System (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation

  8. Dissipation range turbulent cascades in plasmas

    International Nuclear Information System (INIS)

    Terry, P. W.; Almagri, A. F.; Forest, C. B.; Nornberg, M. D.; Rahbarnia, K.; Sarff, J. S.; Fiksel, G.; Hatch, D. R.; Jenko, F.; Prager, S. C.; Ren, Y.

    2012-01-01

    Dissipation range cascades in plasma turbulence are described and spectra are formulated from the scaled attenuation in wavenumber space of the spectral energy transfer rate. This yields spectra characterized by the product of a power law and exponential fall-off, applicable to all scales. Spectral indices of the power law and exponential fall-off depend on the scaling of the dissipation, the strength of the nonlinearity, and nonlocal effects when dissipation rates of multiple fluctuation fields are different. The theory is used to derive spectra for MHD turbulence with magnetic Prandtl number greater than unity, extending previous work. The theory is also applied to generic plasma turbulence by considering the spectrum from damping with arbitrary wavenumber scaling. The latter is relevant to ion temperature gradient turbulence modeled by gyrokinetics. The spectrum in this case has an exponential component that becomes weaker at small scale, giving a power law asymptotically. Results from the theory are compared to three very different types of turbulence. These include the magnetic plasma turbulence of the Madison Symmetric Torus, the MHD turbulence of liquid metal in the Madison Dynamo Experiment, and gyrokinetic simulation of ion temperature gradient turbulence.

  9. Atmospheric propagation of infrasound across mountain ranges

    Science.gov (United States)

    Damiens, Florentin; Millet, Christophe; Lott, Francois

    2017-11-01

    Linear theory of acoustic propagation is used to analyze trapping of infrasound within the lower tropospheric waveguide during propagation above a mountain range. Atmospheric flow produced by the mountains is predicted by a nonlinear mounatin wave model. For the infrasound component, we solve the wave equation under the effective sound speed approximation using both a spectral collocation method and a WKB approach. It is shown that in realistic configurations, the mountain waves can deeply perturb the low level waveguide, which leads to significant acoustic dispersion. To interpret these results each acoustic mode is tracked separately as the horizontal distance increases. It is shown that during statically stable situations, roughly representative of winter or night situations, the mountain waves induce a Foehn effect downstream which shrinks significantly the waveguide. This yields a new form of infrasound absorption, that can largely outweigh the direct effect the moutain induces on the low-level waveguide. For the opposite case, when the low level flow is less statically stable (summer or day situations), mountain wave dynamics do not produce dramatic responses downstream. Instead, it favors the passage of infrasound, which somehow mitigates the direct effect of the obstacle.

  10. Thresholded Range Aggregation in Sensor Networks

    DEFF Research Database (Denmark)

    Yiu, Man Lung; Lin, Zhifeng; Mamoulis, Nikos

    2010-01-01

    The recent advances in wireless sensor technologies (e.g., Mica, Telos motes) enable the economic deployment of lightweight sensors for capturing data from their surrounding environment, serving various monitoring tasks, like forest wildfire alarming and volcano activity. We propose a novel query...... of other nodes in its neighborhood region. Furthermore, we extend our protocols for continuous evaluation of the TRA query. Experimental results show that our proposed solutions indeed offer substantial energy savings for both real and synthetic sensor networks.......The recent advances in wireless sensor technologies (e.g., Mica, Telos motes) enable the economic deployment of lightweight sensors for capturing data from their surrounding environment, serving various monitoring tasks, like forest wildfire alarming and volcano activity. We propose a novel query...... called thresholded range aggregate query (TRA), which retrieves the IDs of the sensors for which the average measurement in their neighborhood exceeds a user-given threshold. This query provides results that they are robust against individual sensor abnormality, and yet precisely summarize the sensors...

  11. Stochastic processes and long range dependence

    CERN Document Server

    Samorodnitsky, Gennady

    2016-01-01

    This monograph is a gateway for researchers and graduate students to explore the profound, yet subtle, world of long-range dependence (also known as long memory). The text is organized around the probabilistic properties of stationary processes that are important for determining the presence or absence of long memory. The first few chapters serve as an overview of the general theory of stochastic processes which gives the reader sufficient background, language, and models for the subsequent discussion of long memory. The later chapters devoted to long memory begin with an introduction to the subject along with a brief history of its development, followed by a presentation of what is currently the best known approach, applicable to stationary processes with a finite second moment. The book concludes with a chapter devoted to the author’s own, less standard, point of view of long memory as a phase transition, and even includes some novel results. Most of the material in the book has not previously been publis...

  12. A long-range laser velocimeter

    Science.gov (United States)

    Reinath, Michael S.

    1991-01-01

    A long-range laser velocimeter (LV) developed for remote operation from within the flow fields of large wind tunnels is described. Emphasis is placed on recent improvements in optical hardware as well as recent additions to data acquisition and processing techniques. The method used for data reduction of photon resolved signals is outlined in detail, and measurement accuracy is discussed. To study the performance of the LV and verify the measurement accuracy, laboratory measurements were made in the flow field of a 10-cm-diameter, 30-m/s axisymetric jet. The measured velocity and turbulence intensity surveys are compared with measurements made with a hot-wire anemometer. Additionally, the LV was used during the flow calibration of the 80-ft x 120-ft wind tunnel to measure the test-section boundary-layer thickness at the maximum wind tunnel speed of 51.5 m/s. The requirements and techniques used to seed the flow are discussed, and boundary-layer surveys of mean velocity and turbulence intensity of the streamwise component and the component normal to the surface are presented. The streamwise component of mean velocity is compared with data obtained with a total pressure rake.

  13. Range of validity of transport equations

    International Nuclear Information System (INIS)

    Berges, Juergen; Borsanyi, Szabolcs

    2006-01-01

    Transport equations can be derived from quantum field theory assuming a loss of information about the details of the initial state and a gradient expansion. While the latter can be systematically improved, the assumption about a memory loss is not known to be controlled by a small expansion parameter. We determine the range of validity of transport equations for the example of a scalar g 2 Φ 4 theory. We solve the nonequilibrium time evolution using the three-loop 2PI effective action. The approximation includes off-shell and memory effects and assumes no gradient expansion. This is compared to transport equations to lowest order (LO) and beyond (NLO). We find that the earliest time for the validity of transport equations is set by the characteristic relaxation time scale t damp =-2ω/Σ ρ (eq) , where -Σ ρ (eq) /2 denotes the on-shell imaginary-part of the self-energy. This time scale agrees with the characteristic time for partial memory loss, but is much shorter than thermal equilibration times. For times larger than about t damp the gradient expansion to NLO is found to describe the full results rather well for g 2 (less-or-similar sign)1

  14. Are fish outside their usual ranges early indicators of climate-driven range shifts?

    Science.gov (United States)

    Fogarty, Hannah E; Burrows, Michael T; Pecl, Gretta T; Robinson, Lucy M; Poloczanska, Elvira S

    2017-05-01

    Shifts in species ranges are a global phenomenon, well known to occur in response to a changing climate. New species arriving in an area may become pest species, modify ecosystem structure, or represent challenges or opportunities for fisheries and recreation. Early detection of range shifts and prompt implementation of any appropriate management strategies is therefore crucial. This study investigates whether 'first sightings' of marine species outside their normal ranges could provide an early warning of impending climate-driven range shifts. We examine the relationships between first sightings and marine regions defined by patterns of local climate velocities (calculated on a 50-year timescale), while also considering the distribution of observational effort (i.e. number of sampling days recorded with biological observations in global databases). The marine trajectory regions include climate 'source' regions (areas lacking connections to warmer areas), 'corridor' regions (areas where moving isotherms converge), and 'sink' regions (areas where isotherms locally disappear). Additionally, we investigate the latitudinal band in which first sightings were recorded, and species' thermal affiliations. We found that first sightings are more likely to occur in climate sink and 'divergent' regions (areas where many rapid and diverging climate trajectories pass through) indicating a role of temperature in driving changes in marine species distributions. The majority of our fish first sightings appear to be tropical and subtropical species moving towards high latitudes, as would be expected in climate warming. Our results indicate that first sightings are likely related to longer-term climatic processes, and therefore have potential use to indicate likely climate-driven range shifts. The development of an approach to detect impending range shifts at an early stage will allow resource managers and researchers to better manage opportunities resulting from range

  15. Relativity Parameters Determined from Lunar Laser Ranging

    Science.gov (United States)

    Williams, J. G.; Newhall, X. X.; Dickey, J. O.

    1996-01-01

    Analysis of 24 years of lunar laser ranging data is used to test the principle of equivalence, geodetic precession, the PPN parameters beta and gamma, and G/G. Recent data can be fitted with a rms scatter of 3 cm. (a) Using the Nordtvedt effect to test the principle of equivalence, it is found that the Moon and Earth accelerate alike in the Sun's field. The relative accelerations match to within 5 x 10(exp -13) . This limit, combined with an independent determination of y from planetary time delay, gives beta. Including the uncertainty due to compositional differences, the parameter beta differs from unity by no more than 0.0014; and, if the weak equivalence principle is satisfied, the difference is no more than 0.0006. (b) Geodetic precession matches its expected 19.2 marc sec/yr rate within 0.7%. This corresponds to a 1% test of gamma. (c) Apart from the Nordtvedt effect, beta and gamma can be tested from their influence on the lunar orbit. It is argued theoretically that the linear combination 0.8(beta) + 1.4(gamma) can be tested at the 1% level of accuracy. For solutions using numerically derived partial derivatives, higher sensitivity is found. Both 6 and y match the values of general relativity to within 0.005, and the linear combination beta+ gamma matches to within 0,003, but caution is advised due to the lack of theoretical understanding of these sensitivities. (d) No evidence for a changing gravitational constant is found, with absolute value of G/G less than or equal to 8 x lO(exp -12)/yr. There is significant sensitivity to G/G through solar perturbations on the lunar orbit.

  16. Long-Range Critical Exponents near the Short-Range Crossover.

    Science.gov (United States)

    Behan, Connor; Rastelli, Leonardo; Rychkov, Slava; Zan, Bernardo

    2017-06-16

    The d-dimensional long-range Ising model, defined by spin-spin interactions decaying with the distance as the power 1/r^{d+s}, admits a second-order phase transition with continuously varying critical exponents. At s=s_{*}, the phase transition crosses over to the usual short-range universality class. The standard field-theoretic description of this family of models is strongly coupled at the crossover. We find a new description, which is instead weakly coupled near the crossover, and use it to compute critical exponents. The existence of two complementary UV descriptions of the same long-range fixed point provides a novel example of infrared duality.

  17. Infinite matter properties and zero-range limit of non-relativistic finite-range interactions

    Energy Technology Data Exchange (ETDEWEB)

    Davesne, D. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, UMR 5822, F-69622 Villeurbanne cedex (France); Becker, P., E-mail: pbecker@ipnl.in2p3.fr [Université de Lyon, Université Lyon 1, CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, UMR 5822, F-69622 Villeurbanne cedex (France); Pastore, A. [Department of Physics, University of York, Heslington, York, Y010 5DD (United Kingdom); Navarro, J. [IFIC (CSIC-Universidad de Valencia), Apartado Postal 22085, E-46.071-Valencia (Spain)

    2016-12-15

    We discuss some infinite matter properties of two finite-range interactions widely used for nuclear structure calculations, namely Gogny and M3Y interactions. We show that some useful informations can be deduced for the central, tensor and spin–orbit terms from the spin–isospin channels and the partial wave decomposition of the symmetric nuclear matter equation of state. We show in particular that the central part of the Gogny interaction should benefit from the introduction of a third Gaussian and the tensor parameters of both interactions can be deduced from special combinations of partial waves. We also discuss the fact that the spin–orbit of the M3Y interaction is not compatible with local gauge invariance. Finally, we show that the zero-range limit of both families of interactions coincides with the specific form of the zero-range Skyrme interaction extended to higher momentum orders and we emphasize from this analogy its benefits.

  18. Predicting Long-Range Traversability from Short-Range Stereo-Derived Geometry

    Science.gov (United States)

    Turmon, Michael; Tang, Benyang; Howard, Andrew; Brjaracharya, Max

    2010-01-01

    Based only on its appearance in imagery, this program uses close-range 3D terrain analysis to produce training data sufficient to estimate the traversability of terrain beyond 3D sensing range. This approach is called learning from stereo (LFS). In effect, the software transfers knowledge from middle distances, where 3D geometry provides training cues, into the far field where only appearance is available. This is a viable approach because the same obstacle classes, and sometimes the same obstacles, are typically present in the mid-field and the farfield. Learning thus extends the effective look-ahead distance of the sensors.

  19. A wide-range magnetic spectrometer for electron scattering in medium energy range

    International Nuclear Information System (INIS)

    Mao Zhenlin

    1988-01-01

    A non-focusing magnetic spectrometer design for electron scattering in medium energy region is proposed. The positions read out from the position-sensitive detectors in the spectrometer are used for track reconstruction and momentum measurement by means of a computer program. The construction of this spectrometer is simple and there is no special technique and element for correction to aberration. It is suitable for usage of spectrometer with large solid angle and wide momentum range. The momentum resolution, momentum range and acceptance in a practical case are calculated by Monte Carlo simulation

  20. Active deformation offshore the Western Transverse Ranges

    Science.gov (United States)

    Ucarkus, G.; Driscoll, N. W.; Brothers, D. S.; Kent, G.; Rockwell, T. K.

    2014-12-01

    The Transverse Ranges within the structural province of southern California, an east-west trending active fold and thrust belt system, has rapid uplift rates that are capable of generating large earthquakes and tsunamis. This system to the west consists of north and south dipping reverse faults offshore Santa Barbara and Ventura (i.e., Pitas Point fault, Red Mountain fault, Rincon Creek fault). Ventura Avenue Anticline (VAA) is one of the fastest uplifting structure within this system has experienced nearly 2.7 km of structural uplift since fold initiation about 200-300 thousand years ago, yielding an average uplift rate of 9-13 mm/yr. Mapped and dated Holocene marine terraces between Ventura and Carpenteria reveal that large uplift events occurred at 0.8 ka and 1.9 ka; a recurrence interval of approximately a thousand years. The VAA trends offshore to the west and is buried by sediment from Rincon Creek. This sediment completely obscures the surficial expression of the fold between Rincon Point and Punta Gorda, indicating that Holocene sedimentation has kept pace with fold growth. Given the high sedimentation rate, each uplift event should be captured by stratigraphic rotation and onlap, and formation of angular unconformities. With that perspective, we acquired ~240 km-long very high-resolution (decimeter) CHIRP seismic reflection data from offshore Santa Barbara in the west to Ventura in the east, in order to examine discrete folding/uplift events that are preserved in the Holocene sediment record. CHIRP data together with re-processed USGS sparker profiles provide new constraints on timing and architecture of deformation offshore. A transgressive surface that dates back to ~9.5 kyr B.P is identified in seismic reflection data and dips landward; bending of the transgressive surface appears to be due to active folding and faulting. Observed onlapping sediments together with the deformation of the transgressive surface mark the onset of deformation while periods

  1. New progress of ranging technology at Wuhan Satellite Laser Ranging Station

    Science.gov (United States)

    Xia, Zhiz-Hong; Ye, Wen-Wei; Cai, Qing-Fu

    1993-01-01

    A satellite laser ranging system with an accuracy of the level of centimeter has been successfully developed at the Institute of Seismology, State Seismological Bureau with the cooperation of the Institute of Geodesy and Geophysics, Chinese Academy of Science. With significant improvements on the base of the second generation SLR system developed in 1985, ranging accuracy of the new system has been upgraded from 15 cm to 3-4 cm. Measuring range has also been expanded, so that the ETALON satellite with an orbit height of 20,000 km launched by the former U.S.S.R. can now be tracked. Compared with the 2nd generation SLR system, the newly developed system has the following improvements. A Q modulated laser is replaced by a mode-locked YAG laser. The new device has a pulse width of 150 ps and a repetition rate of 1-4 pps. A quick response photomultiplier has been adopted as the receiver for echo; for example, the adoption of the MCP tube has obviously reduced the jitter error of the transit time and has improved the ranging accuracy. The whole system is controlled by an IBM PC/XT Computer to guide automatic tracking and measurement. It can carry out these functions for satellite orbit calculation, real-time tracking and adjusting, data acquisition and the preprocessed of observing data, etc. The automatization level and reliability of the observation have obviously improved.

  2. Environmental Assessment (EA) for the Comprehensive Range Plan (CRP), Melrose Air Force Range (AFR), New Mexico

    Science.gov (United States)

    2011-07-01

    loam - gravelly sand - Roods -··- Surface ’Vater [.~ Melrose Range Boundary C Exclusive Use Area r•-... ~ Lease Bomtdary D County - sand 0 5...siting and designing facilities to take into account soil limitations, employing construction and stabilization techniques appropriate for the soils and

  3. Short-range interactions versus long-range correlations in bird flocks.

    Science.gov (United States)

    Cavagna, Andrea; Del Castello, Lorenzo; Dey, Supravat; Giardina, Irene; Melillo, Stefania; Parisi, Leonardo; Viale, Massimiliano

    2015-07-01

    Bird flocks are a paradigmatic example of collective motion. One of the prominent traits of flocking is the presence of long range velocity correlations between individuals, which allow them to influence each other over the large scales, keeping a high level of group coordination. A crucial question is to understand what is the mutual interaction between birds generating such nontrivial correlations. Here we use the maximum entropy (ME) approach to infer from experimental data of natural flocks the effective interactions between individuals. Compared to previous studies, we make a significant step forward as we retrieve the full functional dependence of the interaction on distance, and find that it decays exponentially over a range of a few individuals. The fact that ME gives a short-range interaction even though its experimental input is the long-range correlation function, shows that the method is able to discriminate the relevant information encoded in such correlations and single out a minimal number of effective parameters. Finally, we show how the method can be used to capture the degree of anisotropy of mutual interactions.

  4. Range-Image Acquisition for Discriminated Objects in a Range-gated Robot Vision System

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung-Kyu; Ahn, Yong-Jin; Park, Nak-Kyu; Baik, Sung-Hoon; Choi, Young-Soo; Jeong, Kyung-Min [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The imaging capability of a surveillance vision system from harsh low-visibility environments such as in fire and detonation areas is a key function to monitor the safety of the facilities. 2D and range image data acquired from low-visibility environment are important data to assess the safety and prepare appropriate countermeasures. Passive vision systems, such as conventional camera and binocular stereo vision systems usually cannot acquire image information when the reflected light is highly scattered and absorbed by airborne particles such as fog. In addition, the image resolution captured through low-density airborne particles is decreased because the image is blurred and dimmed by the scattering, emission and absorption. Active vision systems, such as structured light vision and projected stereo vision are usually more robust for harsh environment than passive vision systems. However, the performance is considerably decreased in proportion to the density of the particles. The RGI system provides 2D and range image data from several RGI images and it moreover provides clear images from low-visibility fog and smoke environment by using the sum of time-sliced images. Nowadays, the Range-gated (RG) imaging is an emerging technology in the field of surveillance for security applications, especially in the visualization of invisible night and fog environment. Although RGI viewing was discovered in the 1960's, this technology is, nowadays becoming more applicable by virtue of the rapid development of optical and sensor technologies. Especially, this system can be adopted in robot-vision system by virtue of its compact portable configuration. In contrast to passive vision systems, this technology enables operation even in harsh environments like fog and smoke. During the past decades, several applications of this technology have been applied in target recognition and in harsh environments, such as fog, underwater vision. Also, this technology has been

  5. Range-Image Acquisition for Discriminated Objects in a Range-gated Robot Vision System

    International Nuclear Information System (INIS)

    Park, Seung-Kyu; Ahn, Yong-Jin; Park, Nak-Kyu; Baik, Sung-Hoon; Choi, Young-Soo; Jeong, Kyung-Min

    2015-01-01

    The imaging capability of a surveillance vision system from harsh low-visibility environments such as in fire and detonation areas is a key function to monitor the safety of the facilities. 2D and range image data acquired from low-visibility environment are important data to assess the safety and prepare appropriate countermeasures. Passive vision systems, such as conventional camera and binocular stereo vision systems usually cannot acquire image information when the reflected light is highly scattered and absorbed by airborne particles such as fog. In addition, the image resolution captured through low-density airborne particles is decreased because the image is blurred and dimmed by the scattering, emission and absorption. Active vision systems, such as structured light vision and projected stereo vision are usually more robust for harsh environment than passive vision systems. However, the performance is considerably decreased in proportion to the density of the particles. The RGI system provides 2D and range image data from several RGI images and it moreover provides clear images from low-visibility fog and smoke environment by using the sum of time-sliced images. Nowadays, the Range-gated (RG) imaging is an emerging technology in the field of surveillance for security applications, especially in the visualization of invisible night and fog environment. Although RGI viewing was discovered in the 1960's, this technology is, nowadays becoming more applicable by virtue of the rapid development of optical and sensor technologies. Especially, this system can be adopted in robot-vision system by virtue of its compact portable configuration. In contrast to passive vision systems, this technology enables operation even in harsh environments like fog and smoke. During the past decades, several applications of this technology have been applied in target recognition and in harsh environments, such as fog, underwater vision. Also, this technology has been

  6. 50 CFR 30.1 - Surplus range animals.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Surplus range animals. 30.1 Section 30.1... NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.1 Surplus range animals. Range animals on fenced wildlife refuge areas, including buffalo and longhorn cattle, determined...

  7. Gravity and Magnetic Anomaly Interpretations and 2.5D Cross-Section Models over the Border Ranges Fault System and Aleutian Subduction Zone, Alaska

    Science.gov (United States)

    Mankhemthong, N.; Doser, D. I.; Baker, M. R.; Kaip, G.; Jones, S.; Eslick, B. E.; Budhathoki, P.

    2011-12-01

    Quaternary glacial covers and lack of dense geophysical data on the Kenai Peninsula cause a location and geometry of the Border Ranges fault system (BRFS) within a recent forearc-accretionary boundary of Aleutian subduction zone in southern Alaska are unclear. Using new ~1,300 gravity collections within the Anchorage and Kenai Peninsula regions complied with prior 1997 gravity and aeromagnetic data help us better imaging these fault and the subduction structures. Cook Inlet forearc basin is corresponded by deep gravity anomaly lows; basin boundaries are characterized by a strong gravity gradient, where are considered to be traces of Border Ranges fault system on the east and Castle Mountain and Bruin Bay fault system on the west and northwest of the forearc basin respectively. Gravity anomaly highs over accreted rocks generally increase southeastward to the Aleutian trench, but show a gravity depression over the Kenai Mountains region. The lineament between gravity high and low in the same terrenes over the Kenai Peninsula is may be another evidence to determine the Southern Edge of the Yakutat Microplate (SEY) as inferred by Eberhart-Phillips et al. (2006). Our 2.5-D models illustrate the main fault of the BRFS dips steeply toward the west with a downslip displacement. Gravity and Magnetic anomaly highs, on the east of the BRFS, probably present a slice of the ultramafic complex emplaced by faults along the boundary of the forearc basin and accretionary wedge terranes. Another magnetic high beneath the basin in the southern forearc basin support a serpentiznied body inferred by Saltus et al. (2001), with a decreasing size toward the north. Regional density-gravity models show the Pacific subducting slab beneath the foreacre-arc teranes with a gentle and flatted dip where the subducting plate is located in north of SEY and dips more steeply where it is located on the south of SEY. The gravity depression over the accreted terrene can be explained by a density low

  8. A mass-wasting dominated Quaternary mountain range, the Coastal Range in eastern Taiwan

    Science.gov (United States)

    Hsieh, Meng-Long; Hogg, Alan; Song, Sheng-Rong; Kang, Su-Chen; Chou, Chun-Yen

    2017-12-01

    Fluvial bedrock incision, which creates topographic relief and controls hillslope development, has been considered the key medium linking denudation and tectonic uplift of unglaciated mountains. This article, however, shows a different scenario from the Coastal Range in eastern Taiwan. This range, with the steepness inherited from pre-orogenic volcanoes, has been subject to mass wasting even before its emergence above sea level no earlier than Middle Pleistocene. Numerous terraced alluvial fans/fan deltas record the ancient mass movements of the range, including rock avalanches. Multiple radiocarbon dates 1 km2. Alluvial terraces are typically exhibited close to the source ridges of mass movements, and strath terraces along the downstream parts of rivers. Both were created when enormous sediment supply had exceeded or matched the prevailing river transport capacity. This process, along with the protection by giant boulders from mass movement, disturbed the long-term incision trend of rivers in response to tectonic uplift. As a result, the observed Holocene bedrock incision at most sites has not kept pace with the tectonic uplift. The spatial contrast in mass-wasting histories further accounts for the great diversity of the terrace sequences, even in areas with similar tectonic and base-level conditions.

  9. Precise long-range migration results from short-range stepwise migration during ring gland organogenesis.

    Science.gov (United States)

    Sánchez-Higueras, Carlos; Hombría, James Castelli-Gair

    2016-06-01

    Many organs are specified far from the location they occupy when functional, having to migrate long distances through the heterogeneous and dynamic environment of the early embryo. We study the formation of the main Drosophila endocrine organ, the ring gland, as a new model to investigate in vivo the genetic regulation of collective cell migration. The ring gland results from the fusion of three independent gland primordia that migrate from the head towards the anterior aorta as the embryo is experiencing major morphogenetic movements. To complete their long-range migration, the glands extend filopodia moving sequentially towards a nearby intermediate target and from there to more distal ones. Thus, the apparent long-range migration is composed of several short-range migratory steps that facilitate reaching the final destination. We find that the target tissues react to the gland's proximity by sending filopodia towards it. Our finding of a succession of independent migration stages is consistent with the stepwise evolution of ring gland assembly and fits with the observed gland locations found in extant crustaceans, basal insects and flies. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. A national range inventory for the Kingdom of Lesotho. | Martin ...

    African Journals Online (AJOL)

    Keywords: classification; Colour aerial photography; Ecological sites; ecology; inventory; lesotho; management; management plan; mapping; National range inventories; photo interpretation; photography; plant communities; Plant community relationships; range; range management; rangeland; rangelands; remote sensing; ...

  11. Product numerical range in a space with tensor product structure

    OpenAIRE

    Puchała, Zbigniew; Gawron, Piotr; Miszczak, Jarosław Adam; Skowronek, Łukasz; Choi, Man-Duen; Życzkowski, Karol

    2010-01-01

    We study operators acting on a tensor product Hilbert space and investigate their product numerical range, product numerical radius and separable numerical range. Concrete bounds for the product numerical range for Hermitian operators are derived. Product numerical range of a non-Hermitian operator forms a subset of the standard numerical range containing the barycenter of the spectrum. While the latter set is convex, the product range needs not to be convex nor simply connected. The product ...

  12. Extensional origin of ductile fabrics in the Schist Belt, Central Brooks Range, Alaska—II. Microstructural and petrofabric evidence

    Science.gov (United States)

    Law, Richard D.; Miller, Elizabeth L.; Little, Timothy A.; Lee, Jeffrey

    1994-07-01

    A regional system of S-dipping faults is exposed in the Florence and Fall Creeks area of the south-central Brooks Range. This fault system has previously been mapped as the ·root zone' of a N-vergent fold-and-thrust belt of Jurassic-Cretaceous age, although individual faults juxtapose lower grade on higher grade metamorphic rocks suggesting apparent extensional geometries. The structurally highest of these faults places rocks of the oceanic Paleozoic-Mesozoic Angayucham terrane, together with unconformably overlying Cretaceous clastic rocks, on Devonian metagreywacke and phyllite. This metagreywacke-phyllite (MP) unit in turn structurally overlies Devonian (?) and older basement rocks of the Brooks Range Schist Belt along a S-dipping structural contact previously mapped as the Florence Creek fault. The Schist Belt and MP units are both characterized by a regionally developed, S-dipping greenschist facies foliation that displays a pronounced N-S-trending, down-dip elongation lineation which earlier workers regarded as being associated with N-vergent thrusting. While only one foliation ( Sd) is recognized in the MP unit, in the underlying Schist Belt this foliation ( S2) overprints an earlier blueschist facies mineral assemblage and associated foliation ( S1). Mylonites with strong asymmetric crystal fabrics are well developed in quartz stringers in the MP unit and in Schist Belt rocks located at less than 250 m beneath the Florence Creek fault. These asymmetric single- and cross-girdle c-axis fabrics indicate a top down-to-the-south shear sense. This shear sense is confirmed in XZ sections by the presence of elongate, dynamically recrystallized quartz grains oblique to the Sd - S2 mylonitic foliation. Quartzose and quartzo-feldspathic lithologies become coarser grained in the deeper levels of the Schist Belt, and a greater proportion of the quartz grains are equant in outline suggesting the increasing importance of temperature-sensitive recovery processes. These

  13. Mafic rocks from Erinpura gneiss terrane in the Sirohi region ...

    Indian Academy of Sciences (India)

    The trace element characteristics, such as enriched LIL elements, high Th, absence of negative Nb anomalies and depletion in compatible elements in Daba samples suggest an enriched mantle source and lower degree of melting. The trace and rare earth element characteristics for Kui (Th anomaly, Nb–Ta trough and less ...

  14. Emplacement kinematics of nepheline syenites from the Terrane ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    tiled up in an imbricate fashion (figure 3b). The majority of the minerals in nepheline syenite show uniform extinction, feldspars show straight twin lamellae and hornblende and biotite flakes lack any kind of kink on their cleavage. Thus it has been inferred that the minerals are predominantly of magmatic origin and have not ...

  15. Geochronologic synthesis of the Piedra Alta Terrane, Uruguay

    International Nuclear Information System (INIS)

    Preciozzi, F.; Peel, E.

    2006-01-01

    In the Pre cordillera of Córdoba there are sixteen bands of ductile deformation, which allows tectonic significance assign them to four groups. One of them, which belongs to Deformation Gaza Tunnels, consists of post metamorphic strips uprooting of Orogen Pampeano Cambrian reverse nature, produced by convergent general shear (transpressional), related to collisional stages terrain Posthumous Pampa against Gondwana margin, and famatinian subduction. New radiometric data obtained by the K / Ar method amphiboles and micas allow better narrow activity tectonics of the strip, which would have nucleated after the M2 metamorphic peak (ca. 534 Ma), uprooted the Orogen Cambrian and Ordovician exhumándolo up early (onset of subduction Famatinian), when located the Charquina (474 ​​Ma) granodiorite. The period of tectonic activity FDLT (ca. 64 Ma), coincide with the approach of land Cuyania the Gondwana margin, prior to placement and final collision in the Middle to Late Ordovician. At the same time, in the field Pampeano they would be producing con tractional stages end collision with terrain Pampa the western margin of Gondwana. Subsequently, the FDLT would have cooled to the middle Silurian, when the Sierras de Cordoba and San Luis They continued their exhumation through isotherm muscovite. After cooling this generalized, deformation occurs and Devonian magmatism that penetrativamente affected the Pre cordillera eastern

  16. Tectonics of suspect terranes mountain building and continental growth

    CERN Document Server

    Howell, David G

    1989-01-01

    Year by year the Earth sciences grow more diverse, with an inevitable increase in the degree to which rampant specialization isolates the practitioners of an ever larger number of sub fields. An increasing emphasis on sophisticated mathematics, physics and chemistry as well as the use of advanced technology have. set up barriers often impenetrable to the uninitiated. Ironically, the potential value of many specialities for other, often non-contiguous once has also increased. What is at the present time quiet, unseen work in a remote corner of our discipline, may tomorrow enhance, even revitalize some entirely different area. The rising flood of research reports has drastically cut the time we have available for free reading. The enormous proliferation of journals expressly aimed at small, select audiences has raised the threshold of access to a large part of the literature so much that many of us are unable to cross it. This, most would agree, is not only unfortunate but downright dangerous, limiting by sheer...

  17. Mafic rocks from Erinpura gneiss terrane in the Sirohi region ...

    Indian Academy of Sciences (India)

    Melanie Hertel (both from GeoZentrum Nordbay- ern, Erlangen) for support in ICPMS and XRF analyses. Dr M Shamim Khan is thanked for pro- viding geochemical dataset on Phulad ophiolite samples. Constructive comments from three anony- mous reviewers have been helpful in improving the manuscript. Authors also ...

  18. 50 CFR 30.2 - Disposition of surplus range animals.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled disposal...

  19. Short-range and long-range forces in quantum theory: selected topics

    International Nuclear Information System (INIS)

    Hiller, J.R.

    1980-01-01

    Short-range forces (SRF) are encountered when the effects of the parity-violating (PV) weak neutral current are considered in atomic systems. We consider these and other SRF that are associated with operators that contain delta functions. Identities which convert a delta-function matrix element to that of a global operator are reviewed. Past and possible future applications of such identities are described. It has been found that use of these identities can substantially improve the results obtained with less accurate wave functions. We present a further application to the hyperfine structure of the ground state of lithium where we again find that results are improved by the use of an identity. A long-range force (LRF) is here defined to be one that is associated with a potential V(r) that is asymptotically of the form lambda r - 1 (r 0 /r)/sup N-1/. We use a dispersion-theoretic approach to study LRF between hadrons due to two-glucon exchange within the framework of quantum chromodynamics. Such an LRF is usually related to the presence of a spectrum of physical states that extends to zero mass. A speculative scheme put forward by Feinberg and Sucher is used to avoid requiring the existence of massless gluons as observable particles. Semi-quantitative expressions for the two-glucon exchange potential between hadrons and, in particular, between two nucleons are obtained. Limits on two-gluon corrections to πp forward scattering dispersion relations are used to provide an upper bound for lambda, the coupling constant in the nucleon-nucleon potential. For N greater than or equal to 7, expected on heuristic grounds, we obtain the bound lambda less than or equal to 10 6 , which is very weak; gluon effects as treated here do not lead to significant effects in the dispersion-theoretic analysis of πp scattering

  20. Seamless Flood Forecasting Based on Monthly, Medium-Range and Short-Range Ensemble Prediction Systems

    Science.gov (United States)

    Thielen-Del Pozo, J.; Pappenberger, F.; Bogner, K.; Kalas, M.; de Roo, A.

    2009-04-01

    The hydrological community is looking increasingly at the use of ensemble prediction systems instead of single forecasts to increase flood warning times. International initiatives and research projects such as THORPEX, HEPEX, PREVIEW, or MAP-DPHASE foster successfully the interdisciplinary dialogue between the meteorological and hydrological communities. The European Flood Alert System (EFAS) is a pre-operational example of an early flood warning system based on multiple EPS and poor-man's ensembles weather inputs. EFAS research focuses on the exploration of the EPS stream flow information, their visualisation for different end user communities and their application in risk-based decision-making. EFAS further provides a platform for further research on flash floods, droughts and climate change. Here a case study of Romanian floods in October 2007 is analysed with multiple EPS at different spatial resolutions and lead times. While monthly forecasts are explored as first indicators for potential floods, the early flood warning capacity of EFAS is drawn mainly from medium-range (15 day) EPS forecasts. In addition information from the limited area model EPS (COSMO-LEPS) with much higher spatial resolution but only 5 days lead time are explored for better quantitative forecasts. An outlook contrasting the computational demands with the apparent benefit is given together with a few thoughts on developments that should be addressed in the near future.

  1. A STRUCTURED APPROACH TO VOICE RANGE PROFILE (PHONETOGRAM) ANALYSIS

    NARCIS (Netherlands)

    SULTER, AM; WIT, HP; SCHUTTE, HK; MILLER, DG

    1994-01-01

    A new method to analyze voice range profiles (phonetograms) is described. The structured analysis is based on quantitatively determining the features: shape, area, and ''speaking range'' dynamics, without distorting the shape of phonetograms. The parameter sets describing these features are

  2. Genus Ranges of 4-Regular Rigid Vertex Graphs.

    Science.gov (United States)

    Buck, Dorothy; Dolzhenko, Egor; Jonoska, Nataša; Saito, Masahico; Valencia, Karin

    2015-01-01

    A rigid vertex of a graph is one that has a prescribed cyclic order of its incident edges. We study orientable genus ranges of 4-regular rigid vertex graphs. The (orientable) genus range is a set of genera values over all orientable surfaces into which a graph is embedded cellularly, and the embeddings of rigid vertex graphs are required to preserve the prescribed cyclic order of incident edges at every vertex. The genus ranges of 4-regular rigid vertex graphs are sets of consecutive integers, and we address two questions: which intervals of integers appear as genus ranges of such graphs, and what types of graphs realize a given genus range. For graphs with 2 n vertices ( n > 1), we prove that all intervals [ a, b ] for all a genus ranges. For graphs with 2 n - 1 vertices ( n ≥ 1), we prove that all intervals [ a, b ] for all a genus ranges. We also provide constructions of graphs that realize these ranges.

  3. Tonopah test range - outpost of Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.

    1996-03-01

    Tonopah Test Range is a unique historic site. Established in 1957 by Sandia Corporation, Tonopah Test Range in Nevada provided an isolated place for the Atomic Energy Commission to test ballistics and non-nuclear features of atomic weapons. It served this and allied purposes well for nearly forty years, contributing immeasurably to a peaceful conclusion to the long arms race remembered as the Cold War. This report is a brief review of historical highlights at Tonopah Test Range. Sandia`s Los Lunas, Salton Sea, Kauai, and Edgewood testing ranges also receive abridged mention. Although Sandia`s test ranges are the subject, the central focus is on the people who managed and operated the range. Comments from historical figures are interspersed through the narrative to establish this perspective, and at the end a few observations concerning the range`s future are provided.

  4. ISAR imaging using the instantaneous range instantaneous Doppler method

    CSIR Research Space (South Africa)

    Wazna, TM

    2015-10-01

    Full Text Available In Inverse Synthetic Aperture Radar (ISAR) imaging, the Range Instantaneous Doppler (RID) method is used to compensate for the nonuniform rotational motion of the target that degrades the Doppler resolution of the ISAR image. The Instantaneous Range...

  5. Extending the unambiguous velocity range using multiple carrier frequencies

    DEFF Research Database (Denmark)

    Zhang, Z.; Jakobsson, A.; Nikolov, Svetoslav

    2005-01-01

    Typically, velocity estimators based on the estimation of the Doppler shift will suffer from a limited unambiguous velocity range. Proposed are two novel multiple carrier based velocity estimators extending the velocity range above the Nyquist velocity limit. Numerical simulations indicate...

  6. IceBridge Riegl Laser Altimeter L0 Raw Ranges

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA IceBridge Riegl Laser Altimeter L0 Raw Ranges (ILUTP0) data set contains range to surface measurements taken over Antarctica using the Riegl...

  7. High-Range Scalar Helium Magnetometer (HSHM), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposal describes development of a conceptual design for a High-range Scalar Helium Magnetometer (HSHM) for the field range +/-16 Gauss. The HSHM...

  8. Geographical ranges in macroecology: Processes, patterns and implications

    DEFF Research Database (Denmark)

    Borregaard, Michael Krabbe

    This thesis investigates how ecological patterns at large scale are shaped by the geographic ranges of species. A species’ range is the geographic area in which an animal lives and breeds. The size of such ranges vary tremendously: some species only exist in a tiny area, whereas others, like humans......, are distributed over the entire Earth. Species’ ranges are one of the basic units of the science of macroecology, which deals with patterns in the distribution of life on Earth. An example of such patterns is the large geographic variation in species richness between areas. These patterns are closely linked...... to the ranges of individual species, in two distinct ways: Ecology and evolution determine the ranges of species; and at the same time the ranges of species shape ecological patterns. This link between geographical ranges and macroecological patterns is the subject of the present thesis. To investigate the link...

  9. African Journal of Range and Forage Science: Submissions

    African Journals Online (AJOL)

    African Journal of Range and Forage Science: Submissions. Journal Home > About the Journal > African Journal of Range and Forage Science: Submissions. Log in or Register to get access to full text downloads.

  10. Mappings with closed range and finite dimensional linear spaces

    International Nuclear Information System (INIS)

    Iyahen, S.O.

    1984-09-01

    This paper looks at two settings, each of continuous linear mappings of linear topological spaces. In one setting, the domain space is fixed while the range space varies over a class of linear topological spaces. In the second setting, the range space is fixed while the domain space similarly varies. The interest is in when the requirement that the mappings have a closed range implies that the domain or range space is finite dimensional. Positive results are obtained for metrizable spaces. (author)

  11. The Role of Data Range in Linear Regression

    Science.gov (United States)

    da Silva, M. A. Salgueiro; Seixas, T. M.

    2017-01-01

    Measuring one physical quantity as a function of another often requires making some choices prior to the measurement process. Two of these choices are: the data range where measurements should focus and the number (n) of data points to acquire in the chosen data range. Here, we consider data range as the interval of variation of the independent…

  12. Seasonal herbage production from two range types in southern ...

    African Journals Online (AJOL)

    Seasonal herbage production from two range types in southern Mozambique. JP Muir, A Alage. Abstract. Estimating ideal stocking rates in southern Mozambique based on range productivity is difficult since forage and foggage production of range types receiving different amounts of rainfall have not been quantified to date.

  13. New range of the African buffalo (Syncerus caffer Sparrman, 1772 ...

    African Journals Online (AJOL)

    Buffaloes were located by tracking their expected ranges in the upper Blue Nile Valley and each location was marked using GPS, and superimposed on the known range of buffaloes. The result showed that the present distribution of buffaloes is further extended from their known ranges. Moreover, the presence of several ...

  14. Mountain range specific analog weather forecast model for ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 117; Issue 5. Mountain range specific ... Mountain range specific analog weather forecast model is developed utilizing surface weather observations of reference stations in each mountain range in northwest Himalaya (NW-Himalaya).The model searches past ...

  15. A study of the factors affecting the range of airplanes

    Science.gov (United States)

    Biermann, David

    1937-01-01

    A study was made of the most important factors affecting the range of airplanes. Numerical examples are given showing the effects of different variables on the range of a two-engine airplane. The takeoff problems of long-range airplanes are analyzed.

  16. 16 CFR 309.22 - Determining estimated cruising range.

    Science.gov (United States)

    2010-01-01

    ...-1993-05-20, “Electric Vehicle Energy Consumption and Range Test Procedure.” This incorporation by... lower integer value. (ii) The upper range value shall be determined by multiplying the vehicle's... next lower integer value. (ii) The upper range value for the vehicle while operating exclusively on...

  17. Lead pollution of shooting range soils | Sehube | South African ...

    African Journals Online (AJOL)

    Atotal of eight military shooting ranges were used for this study. Soil samples were collected at each of the eight shooting ranges at the berm, target line, 50 and 100 m from berm. In all of the shooting ranges investigated the highest total lead (Pb) concentrations were found in the bermsoils. Elevated Pb concentrations of 38 ...

  18. On the diurnal ranges of Sea Surface Temperature (SST)

    Indian Academy of Sciences (India)

    This paper describes the variability in the diurnal range of SST in the north Indian Ocean using in situ measurements and tests the suitability of simple regression models in estimating the diurnal range.SST measurements obtained from 1556 drifting and 25 moored buoys were used to determine the diurnal range of SSTs.

  19. Cultural resources of the Santa Rita Experimental Range

    Science.gov (United States)

    John H. Madsen

    2003-01-01

    The Santa Rita Experimental Range is a vast open space with few signs of houses or human habitation, but at one time it was quite the opposite scene. Archaeological surface inspections reveal heavy use of the Range dating back hundreds of years. This paper will review the history of cultural resource management on the Range and provide a timeline of local cultural...

  20. Best Practices Handbook: Traffic Engineering in Range Networks

    Science.gov (United States)

    2016-03-01

    configuration of the attached equipment, using the SNMP signaling protocol. Best Practices Handbook Traffic Engineering in Range Networks, RCC...Telecommunications and Timing Group Document 220-16 BEST PRACTICES HANDBOOK TRAFFIC ENGINEERING IN RANGE NETWORKS...DOCUMENT 220-16 BEST PRACTICES HANDBOOK TRAFFIC ENGINEERING IN RANGE NETWORKS March 2016 Prepared by Timing

  1. Quantitative Analysis of Range Image Patches by NEB Method

    Directory of Open Access Journals (Sweden)

    Wang Wen

    2017-01-01

    Full Text Available In this paper we analyze sampled high dimensional data with the NEB method from a range image database. Select a large random sample of log-valued, high contrast, normalized, 8×8 range image patches from the Brown database. We make a density estimator and we establish 1-dimensional cell complexes from the range image patch data. We find topological properties of 8×8 range image patches, prove that there exist two types of subsets of 8×8 range image patches modelled as a circle.

  2. Final Environmental Impact Statement for Proposed Barry M. Goldwater Range East Range Enhancements (Including First and Second Record of Decision)

    Science.gov (United States)

    2010-10-01

    quality and environmental management. Mary Harclerode Production A.A. Business Administration with 2 years experience. Rachel Healey ...Manned Range 3, Barry M Goldwater Range East, Arizona. EcoPlan Associates Mesa, Arizona. Neuzil, Anna, Jill Hjeilman, Jason Sperinck, Daniel

  3. An Experiment to Measure Range, Range Straggling, Stopping Power, and Energy Straggling of Alpha Particles in Air

    Science.gov (United States)

    Ouseph, P. J.; Mostovych, Andrew

    1978-01-01

    Experiments to measure range, range straggling, stopping power, and energy straggling of alpha particles are discussed in this article. Commercially available equipment with simple modifications is used for these measurements. (Author/GA)

  4. Start-Stop Moment Optimization of Range Extender and Control Strategy Design for Extended -Range Electric Vehicle

    Science.gov (United States)

    Zhao, Jing-bo; Han, Bing-yuan; Bei, Shao-yi

    2017-10-01

    Range extender is the core component of E-REV, its start-stop control determines the operation modes of vehicle. This paper based on a certain type of E-REV, researched constant power control strategy of range extender in extended-range model, to target range as constraint condition, combined with different driving cycle conditions, by correcting battery SOC for range extender start-stop moment, optimized the control strategy of range extender, and established the vehicle and range extender start-stop control simulation model. Selected NEDC and UDDS conditions simulation results show that: under certain target mileage, the range extender running time reduced by 37.2% and 28.2% in the NEDC condition, and running time UDDS conditions were reduced by 40.6% and 33.5% in the UDDS condition, reached the purpose of meeting the vehicle mileage and reducing consumption and emission.

  5. Provenance and detrital zircon geochronologic evolution of lower Brookian foreland basin deposits of the western Brooks Range, Alaska, and implications for early Brookian tectonism

    Science.gov (United States)

    Moore, Thomas; O'Sullivan, Paul B.; Potter, Christopher J.; Donelick, Raymond A.

    2015-01-01

    detritus to the early Brookian foreland basin of the western Brooks Range: (1) local sources in the oceanic Angayucham terrane, which forms the upper plate of the orogen, and (2) a sedimentary source region outside of northern Alaska. Pre-Jurassic zircons and continental grain types suggest the latter detritus was derived from a thick succession of Triassic turbidites in the Russian Far East that were originally shed from source areas in the Uralian-Taimyr orogen and deposited in the South Anyui Ocean, interpreted here as an early Mesozoic remnant basin. Structural thickening and northward emplacement onto the continental margin of Chukotka during the Brookian structural event are proposed to have led to development of a highland source area located in eastern Chukotka, Wrangel Island, and Herald Arch region. The abundance of detritus from this source area in most of the samples argues that the Colville Basin and ancestral foreland basins were supplied by longitudinal sediment dispersal systems that extended eastward along the Brooks Range orogen and were tectonically recycled into the active foredeep as the thrust front propagated toward the foreland. Movement of clastic sedimentary material from eastern Chukotka, Wrangel Island, and Herald Arch into Brookian foreland basins in northern Alaska confirms the interpretations of previous workers that the Brookian deformational belt extends into the Russian Far East and demonstrates that the Arctic Alaska–Chukotka microplate was a unified geologic entity by the Early Cretaceous.

  6. Ultrafast optical ranging using microresonator soliton frequency combs

    Science.gov (United States)

    Trocha, P.; Karpov, M.; Ganin, D.; Pfeiffer, M. H. P.; Kordts, A.; Wolf, S.; Krockenberger, J.; Marin-Palomo, P.; Weimann, C.; Randel, S.; Freude, W.; Kippenberg, T. J.; Koos, C.

    2018-02-01

    Light detection and ranging is widely used in science and industry. Over the past decade, optical frequency combs were shown to offer advantages in optical ranging, enabling fast distance acquisition with high accuracy. Driven by emerging high-volume applications such as industrial sensing, drone navigation, or autonomous driving, there is now a growing demand for compact ranging systems. Here, we show that soliton Kerr comb generation in integrated silicon nitride microresonators provides a route to high-performance chip-scale ranging systems. We demonstrate dual-comb distance measurements with Allan deviations down to 12 nanometers at averaging times of 13 microseconds along with ultrafast ranging at acquisition rates of 100 megahertz, allowing for in-flight sampling of gun projectiles moving at 150 meters per second. Combining integrated soliton-comb ranging systems with chip-scale nanophotonic phased arrays could enable compact ultrafast ranging systems for emerging mass applications.

  7. Long-range correlation and market segmentation in bond market

    Science.gov (United States)

    Wang, Zhongxing; Yan, Yan; Chen, Xiaosong

    2017-09-01

    This paper investigates the long-range auto-correlations and cross-correlations in bond market. Based on Detrended Moving Average (DMA) method, empirical results present a clear evidence of long-range persistence that exists in one year scale. The degree of long-range correlation related to maturities has an upward tendency with a peak in short term. These findings confirm the expectations of fractal market hypothesis (FMH). Furthermore, we have developed a method based on a complex network to study the long-range cross-correlation structure and applied it to our data, and found a clear pattern of market segmentation in the long run. We also detected the nature of long-range correlation in the sub-period 2007-2012 and 2011-2016. The result from our research shows that long-range auto-correlations are decreasing in the recent years while long-range cross-correlations are strengthening.

  8. Target Image Matching Algorithm Based on Binocular CCD Ranging

    Directory of Open Access Journals (Sweden)

    Dongming Li

    2014-01-01

    Full Text Available This paper proposed target image in a subpixel level matching algorithm for binocular CCD ranging, which is based on the principle of binocular CCD ranging. In the paper, firstly, we introduced the ranging principle of the binocular ranging system and deduced a binocular parallax formula. Secondly, we deduced the algorithm which was named improved cross-correlation matching algorithm and cubic surface fitting algorithm for target images matched, and it could achieve a subpixel level matching for binocular CCD ranging images. Lastly, through experiment we have analyzed and verified the actual CCD ranging images, then analyzed the errors of the experimental results and corrected the formula of calculating system errors. Experimental results showed that the actual measurement accuracy of a target within 3 km was higher than 0.52%, which meet the accuracy requirements of the high precision binocular ranging.

  9. Thermal barriers constrain microbial elevational range size via climate variability.

    Science.gov (United States)

    Wang, Jianjun; Soininen, Janne

    2017-08-01

    Range size is invariably limited and understanding range size variation is an important objective in ecology. However, microbial range size across geographical gradients remains understudied, especially on mountainsides. Here, the patterns of range size of stream microbes (i.e., bacteria and diatoms) and macroorganisms (i.e., macroinvertebrates) along elevational gradients in Asia and Europe were examined. In bacteria, elevational range size showed non-significant phylogenetic signals. In all taxa, there was a positive relationship between niche breadth and species elevational range size, driven by local environmental and climatic variables. No taxa followed the elevational Rapoport's rule. Climate variability explained the most variation in microbial mean elevational range size, whereas local environmental variables were more important for macroinvertebrates. Seasonal and annual climate variation showed negative effects, while daily climate variation had positive effects on community mean elevational range size for all taxa. The negative correlation between range size and species richness suggests that understanding the drivers of range is key for revealing the processes underlying diversity. The results advance the understanding of microbial species thermal barriers by revealing the importance of seasonal and diurnal climate variation, and highlight that aquatic and terrestrial biota may differ in their response to short- and long-term climate variability. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Geographical range and local abundance of tree species in China.

    Directory of Open Access Journals (Sweden)

    Haibao Ren

    Full Text Available Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1 whether locally abundant species tend to be geographically widespread; 2 whether species are more abundant towards their range-centers; and 3 how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20-25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km(2, and >90% of 651 species had ranges >10(5 km(2. There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species' abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges.

  11. Range size heritability in Carnivora is driven by geographic constraints.

    Science.gov (United States)

    Machac, Antonin; Zrzavý, Jan; Storch, David

    2011-06-01

    Range size heritability refers to an intriguing pattern where closely related species occupy geographic ranges of similar extent. Its existence may indicate selection on traits emergent only at the species level, with interesting consequences for evolutionary processes. We explore whether range size heritability may be attributable to the fact that range size is largely driven by the size of geographic domains (i.e., continents, biomes, areas given by species' climatic tolerance) that tend to be similar in phylogenetically related species. Using a well-resolved phylogeny of Carnivora, we show that range sizes are indeed constrained by geographic domains and that the phylogenetic signal in range sizes diminishes if the domain sizes are accounted for. Moreover, more detailed delimitation of species' geographic domain leads to a weaker signal in range size heritability, indicating the importance of definition of the null model against which the pattern is tested. Our findings do not reject the hypothesis of range size heritability but rather unravel its underlying mechanisms. Additional analyses imply that evolutionary conservatism in niche breadth delimits the species' geographic domain, which in turn shapes the species' range size. Range size heritability patterns thus emerge as a consequence of this interplay between evolutionary and geographic constraints.

  12. Evolutionary responses to climate change in a range expanding plant.

    Science.gov (United States)

    Macel, Mirka; Dostálek, Tomáš; Esch, Sonja; Bucharová, Anna; van Dam, Nicole M; Tielbörger, Katja; Verhoeven, Koen J F; Münzbergová, Zuzana

    2017-06-01

    To understand the biological effects of climate change, it is essential to take into account species' evolutionary responses to their changing environments. Ongoing climate change is resulting in species shifting their geographical distribution ranges poleward. We tested whether a successful range expanding plant has rapidly adapted to the regional conditions in its novel range, and whether adaptation could be driven by herbivores. Furthermore, we investigated if enemy release occurred in the newly colonized areas and whether plant origins differed in herbivore resistance. Plants were cloned and reciprocally transplanted between three experimental sites across the range. Effects of herbivores on plant performance were tested by individually caging plants with either open or closed cages. There was no indication of (regional) adaptation to abiotic conditions. Plants originating from the novel range were always larger than plants from the core distribution at all experimental sites, with or without herbivory. Herbivore damage was highest and not lowest at the experimental sites in the novel range, suggesting no release from enemy impact. Genotypes from the core were more damaged compared to genotypes from newly colonized areas at the most northern site in the novel range, which was dominated by generalist slug herbivory. We also detected subtle shifts in chemical defenses between the plant origins. Genotypes from the novel range had more inducible defenses. Our results suggest that plants that are expanding their range with climate change may evolve increased vigor and altered herbivore resistance in their new range, analogous to invasive plants.

  13. Evolution of density-dependent movement during experimental range expansions.

    Science.gov (United States)

    Fronhofer, E A; Gut, S; Altermatt, F

    2017-12-01

    Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  14. Field transplants reveal summer constraints on a butterfly range expansion.

    Science.gov (United States)

    Crozier, Lisa G

    2004-09-01

    The geographic ranges of most species are expected to shift to higher elevations and latitudes in response to global warming. But species react to specific environmental changes in individualistic ways, and we are far from a detailed understanding of range-shifts. Summer temperature often limits the ranges of insects and plants, so many range-shifts are expected to track summer warming. I explore this potential range-limiting factor in a case study of a northwardly expanding American butterfly, Atalopedes campestris (Lepidoptera, Hesperiidae). This species has recently colonized the Pacific Northwest, USA, where the mean annual temperature has risen 0.8-1.8 degrees C over the past 100 years. Using field transplant experiments across the current range edge, I measured development time, survivorship, fecundity and predation rates along a naturally occurring thermal gradient of 3 degrees C. Development time was significantly slower outside the current range in eastern Washington (WA), as expected because of cooler temperatures there. Slower development would reduce the number of generations possible per year outside the current range, dramatically lowering the probability that a population could survive there. Differences in survivorship, fecundity and predation rate across the range edge were not significant. The interaction between summer and winter temperature appears to be crucial in defining the current range limit. The estimated difference in temperature required to affect the number of generations is greater than the extent of summer warming observed over the past century, however, and thus historically winter temperature alone probably limited the range in southeastern WA. Nonetheless, extraordinarily warm summers may have improved colonization success, increasing the probability of a range expansion. These results suggest that extreme climatic events may influence rates of response to long-term climate change. They also demonstrate that range-limiting factors

  15. Parameter Estimation for GRACE-FO Geometric Ranging Errors

    Science.gov (United States)

    Wegener, H.; Mueller, V.; Darbeheshti, N.; Naeimi, M.; Heinzel, G.

    2017-12-01

    Onboard GRACE-FO, the novel Laser Ranging Instrument (LRI) serves as a technology demonstrator, but it is a fully functional instrument to provide an additional high-precision measurement of the primary mission observable: the biased range between the two spacecraft. Its (expectedly) two largest error sources are laser frequency noise and tilt-to-length (TTL) coupling. While not much can be done about laser frequency noise, the mechanics of the TTL error are widely understood. They depend, however, on unknown parameters. In order to improve the quality of the ranging data, it is hence essential to accurately estimate these parameters and remove the resulting TTL error from the data.Means to do so will be discussed. In particular, the possibility of using calibration maneuvers, the utility of the attitude information provided by the LRI via Differential Wavefront Sensing (DWS), and the benefit from combining ranging data from LRI with ranging data from the established microwave ranging, will be mentioned.

  16. OVERLAP OF HEARING AND VOICING RANGES IN SINGING

    Science.gov (United States)

    Hunter, Eric J.; Titze, Ingo R.

    2008-01-01

    Frequency and intensity ranges in voice production by trained and untrained singers were superimposed onto the average normal human hearing range. The vocal output for all subjects was shown both in Voice Range Profiles and Spectral Level Profiles. Trained singers took greater advantage of the dynamic range of the auditory system with harmonic energy (45% of the hearing range compared to 38% for untrained vocalists). This difference seemed to come from the trained singers ablily to exploit the most sensitive part of the hearing range (around 3 to 4 kHz) through the use of the singer’s formant. The trained vocalists’ average maximum third-octave spectral band level was 95 dB SPL, compared to 80 dB SPL for untrained. PMID:19844607

  17. Simulated Research on Passive Sonar Range Using Different Hydrographic Conditions

    OpenAIRE

    Han Jing; Zhang XueGang; Meng ChunXia; Cao Feng

    2015-01-01

    As an example using the passive sonar, it calculated the quality factor of passive sonar using the sonar equation. The sound field was calculated under different depth and range using multiform hydrographic conditions. The isoline of passive sonar quality factor was marked out on the sound field. The isoline also represented the passive sonar range. The simulation results showed that hydrographic conditions had important effect on passive sonar range. At the same hydrographic cond...

  18. Basis convergence of range-separated density-functional theory.

    Science.gov (United States)

    Franck, Odile; Mussard, Bastien; Luppi, Eleonora; Toulouse, Julien

    2015-02-21

    Range-separated density-functional theory (DFT) is an alternative approach to Kohn-Sham density-functional theory. The strategy of range-separated density-functional theory consists in separating the Coulomb electron-electron interaction into long-range and short-range components and treating the long-range part by an explicit many-body wave-function method and the short-range part by a density-functional approximation. Among the advantages of using many-body methods for the long-range part of the electron-electron interaction is that they are much less sensitive to the one-electron atomic basis compared to the case of the standard Coulomb interaction. Here, we provide a detailed study of the basis convergence of range-separated density-functional theory. We study the convergence of the partial-wave expansion of the long-range wave function near the electron-electron coalescence. We show that the rate of convergence is exponential with respect to the maximal angular momentum L for the long-range wave function, whereas it is polynomial for the case of the Coulomb interaction. We also study the convergence of the long-range second-order Møller-Plesset correlation energy of four systems (He, Ne, N2, and H2O) with cardinal number X of the Dunning basis sets cc - p(C)V XZ and find that the error in the correlation energy is best fitted by an exponential in X. This leads us to propose a three-point complete-basis-set extrapolation scheme for range-separated density-functional theory based on an exponential formula.

  19. Unmanned Aerial Vehicle Mishap Taxonomy for Range Safety Reviews

    Science.gov (United States)

    2016-02-01

    Safety Group Published by Secretariat Range Commanders Council White Sands Missile Range New Mexico 88002-5100 This page...gear failure to deploy  Tail damage due to the vehicle’s sudden stop and backwards tilt on an inclined taxiway In one instance, runway operations... Technology . (19 March 2007.):44. Unmanned Aerial Vehicle Mishap Taxonomy for Range Safety Reviews, RCC 326-16, February 2016 6-4 This page intentionally

  20. Numerical challenges of short range wake field calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Thomas; Gjonaj, Erion; Weiland, Thomas [Technische Universitaet Darmstadt (Germany). Institut fuer Theorie Elektromagnetischer Felder (TEMF)

    2011-07-01

    For present and future accelerator projects with ultra short bunches the accurate and reliable calculation of short range wake fields is an important issue. However, the numerical calculation of short range wake fields is a numerical challenging task. The presentation gives an overview over the numerical challenges and techniques for short range wake field calculations. Finally, some simulation results obtained by the program PBCI developed at the TU Darmstadt are presented.

  1. Firing Range Contaminants and Climate Change Tool: Spreadsheet User Instructions

    Science.gov (United States)

    2017-09-18

    Change spreadsheet was developed as a tool to help assess the cost of range management strategies for various potential climate futures.* The subsections...scenarios using the discount rate input by the user. Range managers may use this graph to choose a primary management strategy for the range. Managers...utilizes the “Likelihood of Occurrence” provided for each assessed climate scenario. This is useful in choosing a management strategy considering multiple

  2. Sierra Nevada Yellow-legged Frog Range - CWHR [ds592

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  3. California Red-Legged Frog Range - CWHR [ds587

    Data.gov (United States)

    California Natural Resource Agency — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  4. Target Detection and Ranging through Lossy Media using Chaotic Radar

    Directory of Open Access Journals (Sweden)

    Bingjie Wang

    2015-04-01

    Full Text Available A chaotic radar system has been developed for through-wall detection and ranging of targets. The chaotic signal generated by an improved Colpitts oscillator is designed as a probe signal. Ranging to target is achieved by the cross-correlation between the time-delayed reflected return signal and the replica of the transmitted chaotic signal. In this paper, we explore the performance of the chaotic radar system for target detection and ranging through lossy media. Experimental results show that the designed chaotic radar has the advantages of high range resolution, unambiguous correlation profile, and can be used for through wall target detection and sensing.

  5. Passive Wireless Temperature Sensors with Enhanced Sensitivity and Range Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes the development of passive surface acoustic wave (SAW) temperature sensors with enhanced sensitivity and detection range for NASA application...

  6. Sierra Madre Yellow-legged Frog Range - CWHR [ds613

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  7. California Red-Legged Frog Range - CWHR [ds587

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  8. Foothill Yellow-legged Frog Range - CWHR [ds589

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  9. Double-crested Cormorant Range - CWHR [ds602

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for...

  10. Accuracy of parameterized proton range models; A comparison

    Science.gov (United States)

    Pettersen, H. E. S.; Chaar, M.; Meric, I.; Odland, O. H.; Sølie, J. R.; Röhrich, D.

    2018-03-01

    An accurate calculation of proton ranges in phantoms or detector geometries is crucial for decision making in proton therapy and proton imaging. To this end, several parameterizations of the range-energy relationship exist, with different levels of complexity and accuracy. In this study we compare the accuracy of four different parameterizations models for proton range in water: Two analytical models derived from the Bethe equation, and two different interpolation schemes applied to range-energy tables. In conclusion, a spline interpolation scheme yields the highest reproduction accuracy, while the shape of the energy loss-curve is best reproduced with the differentiated Bragg-Kleeman equation.

  11. Topology Data Analysis of 9×9 Range Image Patches

    Science.gov (United States)

    Wang, Wen

    2018-01-01

    We use the NEB method to deal with data with the property of high dimension from a range image database. From the Brown database we select a large random sample of log-valued, high contrast, normalized, 9×9 range image patches. We create a Morse function via a density estimator. we make 1-dimensional cell complexes from the image data. We detect some topological properties of 9×9 range image patches, find that there exist two types of subsets of 9×9 range image patches modelled as a ring.

  12. Desirable forest structures for a restored Front Range

    Science.gov (United States)

    Yvette L. Dickinson; Rob Addington; Greg Aplet; Mike Babler; Mike Battaglia; Peter Brown; Tony Cheng; Casey Cooley; Dick Edwards; Jonas Feinstein; Paula Fornwalt; Hal Gibbs; Megan Matonis; Kristen Pelz; Claudia Regan

    2014-01-01

    As part of the federal Collaborative Forest Landscape Restoration Program administered by the US Forest Service, the Colorado Front Range Collaborative Forest Landscape Restoration Project (FR-CFLRP, a collaborative effort of the Front Range Roundtable1 and the US Forest Service) is required to define desired conditions for lower montane ponderosa pine (Pinus ponderosa...

  13. 5 CFR 9701.322 - Setting and adjusting rate ranges.

    Science.gov (United States)

    2010-01-01

    ... SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Setting and Adjusting Rate Ranges... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Setting and adjusting rate ranges. 9701.322 Section 9701.322 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES...

  14. 5 CFR 9901.322 - Setting and adjusting rate ranges.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Setting and adjusting rate ranges. 9901.322 Section 9901.322 Administrative Personnel DEPARTMENT OF DEFENSE HUMAN RESOURCES MANAGEMENT AND... NATIONAL SECURITY PERSONNEL SYSTEM (NSPS) Pay and Pay Administration Rate Ranges and General Salary...

  15. Modelling the effect of climate change on species ranges

    NARCIS (Netherlands)

    Nagelkerke, C.J.; Alkemade, J.R.M.

    2003-01-01

    Three main types of models can be used to understand and predict climate-related range shifts. Equilibrium models predict potential future distributions from the current climate envelope of a species, but do not take migration constraints into account. They show that future range changes can be

  16. Scientific considerations on the improvement of the range of ...

    African Journals Online (AJOL)

    This article provides the results of the investigation of biological effectiveness and the development of the regulations on the use of new agents for the improvement and expansion of the range of herbicides for the protection of sunflower crops. Keywords: range of pesticides, herbicides, sunflower, weeds, biological ...

  17. Logarithmic scaling in the near-dissipation range of turbulence

    Indian Academy of Sciences (India)

    From experimental data at moderate Reynolds numbers, it is shown that the logarithmic scaling, deduced from general considerations for the near-dissipation range, covers almost the entire range of scales (about two decades) of structure functions, for both velocity and passive scalar fields. This new scaling requires two ...

  18. Short-range order of germanium selenide glass

    Indian Academy of Sciences (India)

    tion in technological devices, such as optical fibers, memory materials and switching devices, but their use is limited due to several factors. One of them is the difficulty in obtain- ing information about atomic structures. The structure of chalcogenide glasses in the short-range order (SRO) or intermediate-range order (IRO) is ...

  19. The Geologic Story of Colorado's Sangre de Cristo Range

    Science.gov (United States)

    Lindsey, David A.

    2010-01-01

    There is no record of the beginning of time in the Sangre de Cristo Range. Almost 3 billion years of Earth history are missing, but the rest is on spectacular display in this rugged mountain landscape. This is the geologic story of the Sangre de Cristo Range.

  20. Passive ranging with flank and towed array sensors

    NARCIS (Netherlands)

    Beerens, S.P.; IJsselmuide, S.P. van; Koersel, A.C. van

    2003-01-01

    In the current sensor suites on board submarines the Passive Ranging Sonar (PRS) is a separate sensor, usually with three or more hydrophone groups on either side of the submarine. The aperture of this sensor is limited by the length of the boat, which makes ranging up to moderate distances

  1. Reference Ranges for Some Biochemical Parameters in Adult ...

    African Journals Online (AJOL)

    PURPOSE: To establish the reference ranges of some biochemical parameters for adult Kenyan population. METHODS: In a prospective involving 1100 healthy blood donors (age: 18-55 yr) in Kenyatta National Hospital, Kenya reference ranges of some biochemical analytes were constructed by using the parametric ...

  2. Landscape heterogeneity-biodiversity relationship: effect of range size.

    Directory of Open Access Journals (Sweden)

    Naoki Katayama

    Full Text Available The importance of landscape heterogeneity to biodiversity may depend on the size of the geographic range of species, which in turn can reflect species traits (such as habitat generalization and the effects of historical and contemporary land covers. We used nationwide bird survey data from Japan, where heterogeneous landscapes predominate, to test the hypothesis that wide-ranging species are positively associated with landscape heterogeneity in terms of species richness and abundance, whereas narrow-ranging species are positively associated with landscape homogeneity in the form of either open or forest habitats. We used simultaneous autoregressive models to explore the effects of climate, evapotranspiration, and landscape heterogeneity on the richness and abundance of breeding land-bird species. The richness of wide-ranging species and the total species richness were highest in heterogeneous landscapes, where many wide-ranging species showed the highest abundance. In contrast, the richness of narrow-ranging species was not highest in heterogeneous landscapes; most of those species were abundant in either open or forest landscapes. Moreover, in open landscapes, narrow-ranging species increased their species richness with decreasing temperature. These results indicate that heterogeneous landscapes are associated with rich bird diversity but that most narrow-ranging species prefer homogeneous landscapes--particularly open habitats in colder regions, where grasslands have historically predominated. There is a need to reassess the generality of the heterogeneity-biodiversity relationship, with attention to the characteristics of species assemblages determined by environments at large spatiotemporal scales.

  3. Landscape Heterogeneity–Biodiversity Relationship: Effect of Range Size

    Science.gov (United States)

    Katayama, Naoki; Amano, Tatsuya; Naoe, Shoji; Yamakita, Takehisa; Komatsu, Isamu; Takagawa, Shin-ichi; Sato, Naoto; Ueta, Mutsuyuki; Miyashita, Tadashi

    2014-01-01

    The importance of landscape heterogeneity to biodiversity may depend on the size of the geographic range of species, which in turn can reflect species traits (such as habitat generalization) and the effects of historical and contemporary land covers. We used nationwide bird survey data from Japan, where heterogeneous landscapes predominate, to test the hypothesis that wide-ranging species are positively associated with landscape heterogeneity in terms of species richness and abundance, whereas narrow-ranging species are positively associated with landscape homogeneity in the form of either open or forest habitats. We used simultaneous autoregressive models to explore the effects of climate, evapotranspiration, and landscape heterogeneity on the richness and abundance of breeding land-bird species. The richness of wide-ranging species and the total species richness were highest in heterogeneous landscapes, where many wide-ranging species showed the highest abundance. In contrast, the richness of narrow-ranging species was not highest in heterogeneous landscapes; most of those species were abundant in either open or forest landscapes. Moreover, in open landscapes, narrow-ranging species increased their species richness with decreasing temperature. These results indicate that heterogeneous landscapes are associated with rich bird diversity but that most narrow-ranging species prefer homogeneous landscapes—particularly open habitats in colder regions, where grasslands have historically predominated. There is a need to reassess the generality of the heterogeneity-biodiversity relationship, with attention to the characteristics of species assemblages determined by environments at large spatiotemporal scales. PMID:24675969

  4. Landscape heterogeneity-biodiversity relationship: effect of range size.

    Science.gov (United States)

    Katayama, Naoki; Amano, Tatsuya; Naoe, Shoji; Yamakita, Takehisa; Komatsu, Isamu; Takagawa, Shin-ichi; Sato, Naoto; Ueta, Mutsuyuki; Miyashita, Tadashi

    2014-01-01

    The importance of landscape heterogeneity to biodiversity may depend on the size of the geographic range of species, which in turn can reflect species traits (such as habitat generalization) and the effects of historical and contemporary land covers. We used nationwide bird survey data from Japan, where heterogeneous landscapes predominate, to test the hypothesis that wide-ranging species are positively associated with landscape heterogeneity in terms of species richness and abundance, whereas narrow-ranging species are positively associated with landscape homogeneity in the form of either open or forest habitats. We used simultaneous autoregressive models to explore the effects of climate, evapotranspiration, and landscape heterogeneity on the richness and abundance of breeding land-bird species. The richness of wide-ranging species and the total species richness were highest in heterogeneous landscapes, where many wide-ranging species showed the highest abundance. In contrast, the richness of narrow-ranging species was not highest in heterogeneous landscapes; most of those species were abundant in either open or forest landscapes. Moreover, in open landscapes, narrow-ranging species increased their species richness with decreasing temperature. These results indicate that heterogeneous landscapes are associated with rich bird diversity but that most narrow-ranging species prefer homogeneous landscapes--particularly open habitats in colder regions, where grasslands have historically predominated. There is a need to reassess the generality of the heterogeneity-biodiversity relationship, with attention to the characteristics of species assemblages determined by environments at large spatiotemporal scales.

  5. Effects of GPS sampling intensity on home range analyses

    Science.gov (United States)

    Jeffrey J. Kolodzinski; Lawrence V. Tannenbaum; David A. Osborn; Mark C. Conner; W. Mark Ford; Karl V. Miller

    2010-01-01

    The two most common methods for determining home ranges, minimum convex polygon (MCP) and kernel analyses, can be affected by sampling intensity. Despite prior research, it remains unclear how high-intensity sampling regimes affect home range estimations. We used datasets from 14 GPS-collared, white-tailed deer (Odocoileus virginianus) to describe...

  6. Assessment of range planting as a conservation practice [Chapter 4

    Science.gov (United States)

    Stuart P. Hardegree; Thomas A. Jones; Bruce A. Roundy; Nancy L. Shaw; Thomas A. Monaco

    2011-01-01

    The Range Planting Conservation Practice Standard is used to inform development of Natural Resource Conservation Service (NRCS) management recommendations for improving vegetation composition and productivity of grazed plant communities. Range planting recommendations are generally implemented within an integrated conservation management system in conjunction with...

  7. Long-range interactions in dilute granular systems

    NARCIS (Netherlands)

    Müller, M.K

    2008-01-01

    In this thesis, on purpose, we focussed on the most challenging, longest ranging potentials. We analyzed granular media of low densities obeying 1/r long-range interaction potentials between the granules. Such systems are termed granular gases and differ in their behavior from ordinary gases by

  8. Epidemiological reference ranges for low-density lipoprotein ...

    African Journals Online (AJOL)

    The combined use of epidemiological reference ranges for TC and incomplete or statistical reference ranges for LDL-C and Apo-B is illogical, since these parameters may fall into discordant risk categories that will hamper and complicate the management of hypercholesterolaemia. Based on a study of Iipograms obtained ...

  9. Correlation between passive and dynamic range of rotation in lead ...

    African Journals Online (AJOL)

    ... between the passive hip range of movement and dynamic hip range during the golf swing of the trail hip. Clinicians and coaches should thus note that improving passive hip ROM might not be associated with an increased hip rotation utilised during the golf swing. Key words: Lower limb rotation; Golf swing biomechanics; ...

  10. Behaviour - The keystone in optimizing free-ranging ungulate production

    Science.gov (United States)

    Free-ranging animal behaviour is a keystone to optimizing free-ranging domestic animal production. This chapter focuses on several aspects that emanate from foraging including defining terms, concepts and the complexity that underlie managing animals and landscapes. Behaviour is investigated in li...

  11. Effect of visible range electromagnetic radiations on Escherichia coli ...

    African Journals Online (AJOL)

    Background: Escherichia coli is the agent responsible for a range of clinical diseases. With emerging antimicrobial resistance, other treatment options including solar/photo-therapy are becoming increasingly common. Visible Range Radiation Therapy/Colour Therapy is an emerging technique in the field of ...

  12. On-line battery identification for electric driving range prediction

    NARCIS (Netherlands)

    Kessels, J.T.B.A.; Rosca, B.; Bergveld, H.J.; Bosch, P.P.J. van den

    2011-01-01

    Hybrid and electric vehicles require accurate knowledge of the battery to make an educated guess about the expected electric driving range. Range prediction is complicated by the fact that batteries are subject to external influences and aging. Also the future driving behavior is often unknown. This

  13. 42 CFR 1008.59 - Range of the advisory opinion.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Range of the advisory opinion. 1008.59 Section 1008... AUTHORITIES ADVISORY OPINIONS BY THE OIG Scope and Effect of OIG Advisory Opinions § 1008.59 Range of the advisory opinion. (a) An advisory opinion will state only the OIG's opinion regarding the subject matter of...

  14. Detection Range of Airborne Magnetometers in Magnetic Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Chengjing Li

    2015-11-01

    Full Text Available Airborne magnetometers are utilized for the small-range search, precise positioning, and identification of the ferromagnetic properties of underwater targets. As an important performance parameter of sensors, the detection range of airborne magnetometers is commonly set as a fixed value in references regardless of the influences of environment noise, target magnetic properties, and platform features in a classical model to detect airborne magnetic anomalies. As a consequence, deviation in detection ability analysis is observed. In this study, a novel detection range model is proposed on the basis of classic detection range models of airborne magnetometers. In this model, probability distribution is applied, and the magnetic properties of targets and the environment noise properties of a moving submarine are considered. The detection range model is also constructed by considering the distribution of the moving submarine during detection. A cell-averaging greatest-of-constant false alarm rate test method is also used to calculate the detection range of the model at a desired false alarm rate. The detection range model is then used to establish typical submarine search probabilistic models. Results show that the model can be used to evaluate not only the effects of ambient magnetic noise but also the moving and geomagnetic features of the target and airborne detection platform. The model can also be utilized to display the actual operating range of sensor systems.

  15. 47 CFR 15.33 - Frequency range of radiated measurements.

    Science.gov (United States)

    2010-10-01

    ... current system not intended to radiate, shall be investigated from the lowest radio frequency generated or... with the antenna conduction limits specified in § 15.111. The frequency range of measurements for AC... 47 Telecommunication 1 2010-10-01 2010-10-01 false Frequency range of radiated measurements. 15.33...

  16. Efficient external memory structures for range-aggregate queries

    DEFF Research Database (Denmark)

    Agarwal, P.K.; Yang, J.; Arge, L.

    2013-01-01

    We present external memory data structures for efficiently answering range-aggregate queries. The range-aggregate problem is defined as follows: Given a set of weighted points in Rd, compute the aggregate of the weights of the points that lie inside a d-dimensional orthogonal query rectangle. The...

  17. 47 CFR 90.371 - Dedicated short range communications service.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Dedicated short range communications service. 90.371 Section 90.371 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Communications Service (dsrcs) § 90.371 Dedicated short range communications service. (a) These provisions...

  18. Infinite range correlations of intensity in random media

    Indian Academy of Sciences (India)

    We study a new type of long-range correlations for waves propagating in a random medium. These correlations originate from scattering events which take place close to a point source. The scattered waves propagate by diffusion to distant regions. In this way long range correlations, between any pair of distant points, are ...

  19. Infinite range correlations of intensity in random media

    Indian Academy of Sciences (India)

    Infinite range correlations of intensity in random media. A RETZKER and B SHAPIRO. Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel. Abstract. We study a new type of long-range correlations for waves propagating in a random medium. These correlations originate from scattering events ...

  20. A Range-Based Multivariate Model for Exchange Rate Volatility

    NARCIS (Netherlands)

    B. Tims (Ben); R.J. Mahieu (Ronald)

    2003-01-01

    textabstractIn this paper we present a parsimonious multivariate model for exchange rate volatilities based on logarithmic high-low ranges of daily exchange rates. The multivariate stochastic volatility model divides the log range of each exchange rate into two independent latent factors, which are

  1. Short-range self-pulsed optical radar

    Science.gov (United States)

    Berdahl, C. M.

    1981-01-01

    Laser for radar device is retriggered when previous laser pulse is reflected from target. Target range R is computed from number of pulses triggered per time interval. Radar accurately measures distances up to 500 meters; it is useful for determining surface shape of relfectors in large, high-gain, highly directional antennas and for other short-range surveying.

  2. Short Range Stabilization Actions: Good But Not Enough.

    Science.gov (United States)

    Kemerer, Frank R.

    An alternative approach to achieve short-time enrollment stabilization based in part on experiences at the State University of New York, Geneseo, is described. It is suggested that a short-range effort will not be enough to assure institutional vitality in the difficult years ahead. Short-range stabilization should be followed by the integration…

  3. Range expansion of the hadeda ibis Bostrychia hagedash in ...

    African Journals Online (AJOL)

    The southern African range of the habeda ibis Bostrychia hagedash has expanded from 530 900 km 2 in 1910 to 1 323 300 km2 in 1985. Major range expansions have occurred in the fynbos biome of the south-western Cape, the Karoo, the grasslands of the eastern Cape, the Orange Free State and the Transvaal highveld.

  4. Evolutionary responses to climate change in a range expanding plant

    NARCIS (Netherlands)

    Macel, Mirka; Dostálek, Tomás; Esch, Sonja; Bucharová, Anna; van Dam, Nicole M.; Tielbörger, Katja; Verhoeven, Koen J. F.; Münzbergová, Zuzana

    2017-01-01

    To understand the biological effects of climate change, it is essential to take into account species' evolutionary responses to their changing environments. Ongoing climate change is resulting in species shifting their geographical distribution ranges poleward. We tested whether a successful range

  5. Home range and habitat use of Trumpeter Hornbills Bycanistes ...

    African Journals Online (AJOL)

    This study supports the use of more than one method of home range estimation for insight regarding home range and habitat use in urban–forest mosaics for this large forest frugivore. Keywords: Bycanistes bucinator, GPS telemetry, kernel density estimation, local convex hull, minimum convex polygon, urbanisation ...

  6. Range Information Systems Management (RISM) Phase 1 Report

    Science.gov (United States)

    Bastin, Gary L.; Harris, William G.; Nelson, Richard A.

    2002-01-01

    RISM investigated alternative approaches, technologies, and communication network architectures to facilitate building the Spaceports and Ranges of the future. RISM started by document most existing US ranges and their capabilities. In parallel, RISM obtained inputs from the following: 1) NASA and NASA-contractor engineers and managers, and; 2) Aerospace leaders from Government, Academia, and Industry, participating through the Space Based Range Distributed System Working Group (SBRDSWG), many of whom are also; 3) Members of the Advanced Range Technology Working Group (ARTWG) subgroups, and; 4) Members of the Advanced Spaceport Technology Working Group (ASTWG). These diverse inputs helped to envision advanced technologies for implementing future Ranges and Range systems that builds on today s cabled and wireless legacy infrastructures while seamlessly integrating both today s emerging and tomorrow s building-block communication techniques. The fundamental key is to envision a transition to a Space Based Range Distributed Subsystem. The enabling concept is to identify the specific needs of Range users that can be solved through applying emerging communication tech

  7. Report of the Long-Range Planning Committee

    International Nuclear Information System (INIS)

    1984-01-01

    This is the final report of the Long-Range Planning Committee of the Lawrence Livermore National Laboratory. It describes the make-up, purpose, working assumptions, and activities of the Committee and discusses the work done by the Committee on defense matters, energy, a number of additional topics, and future long-range planning activities

  8. Exposure to lead in South African shooting ranges

    International Nuclear Information System (INIS)

    Mathee, Angela; Jager, Pieter de; Naidoo, Shan; Naicker, Nisha

    2017-01-01

    Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

  9. Decreasing range resolution of a SAR image to permit correction of motion measurement errors beyond the SAR range resolution

    Science.gov (United States)

    Doerry, Armin W.; Heard, Freddie E.; Cordaro, J. Thomas

    2010-07-20

    Motion measurement errors that extend beyond the range resolution of a synthetic aperture radar (SAR) can be corrected by effectively decreasing the range resolution of the SAR in order to permit measurement of the error. Range profiles can be compared across the slow-time dimension of the input data in order to estimate the error. Once the error has been determined, appropriate frequency and phase correction can be applied to the uncompressed input data, after which range and azimuth compression can be performed to produce a desired SAR image.

  10. Flight mode affects allometry of migration range in birds.

    Science.gov (United States)

    Watanabe, Yuuki Y

    2016-08-01

    Billions of birds migrate to exploit seasonally available resources. The ranges of migration vary greatly among species, but the underlying mechanisms are poorly understood. I hypothesise that flight mode (flapping or soaring) and body mass affect migration range through their influence on flight energetics. Here, I compiled the tracks of migratory birds (196 species, weighing 12-10 350 g) recorded by electronic tags in the last few decades. In flapping birds, migration ranges decreased with body mass, as predicted from rapidly increasing flight cost with increasing body mass. The species with higher aspect ratio and lower wing loading had larger migration ranges. In soaring birds, migration ranges were mass-independent and larger than those of flapping birds, reflecting their low flight costs irrespective of body mass. This study demonstrates that many animal-tracking studies are now available to explore the general patterns and the underlying mechanisms of animal migration. © 2016 John Wiley & Sons Ltd/CNRS.

  11. Degeneracy and long-range correlation: A simulation study

    Directory of Open Access Journals (Sweden)

    Marmelat Vivien

    2011-12-01

    Full Text Available We present in this paper a simulation study that aimed at evidencing a causal relationship between degeneracy and long-range correlations. Long-range correlations represent a very specific form of fluctuations that have been evidenced in the outcomes time series produced by a number of natural systems. Long-range correlations are supposed to sign the complexity, adaptability and flexibility of the system. Degeneracy is defined as the ability of elements that are structurally different to perform the same function, and is presented as a key feature for explaining the robustness of complex systems. We propose a model able to generate long-range correlated series, and including a parameter that account for degeneracy. Results show that a decrease in degeneracy tends to reduce the strength of long-range correlation in the series produced by the model.

  12. Rocky Flats Plant Live-Fire Range Risk Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Nicolosi, S.L.; Rodriguez, M.A.

    1994-04-01

    The objective of the Live-Fire Range Risk Analysis Report (RAR) is to provide an authorization basis for operation as required by DOE 5480.16. The existing Live-Fire Range does not have a safety analysis-related authorization basis. EG&G Rocky Flats, Inc. has worked with DOE and its representatives to develop a format and content description for development of an RAR for the Live-Fire Range. Development of the RAR is closely aligned with development of the design for a baffle system to control risks from errant projectiles. DOE 5480.16 requires either an RAR or a safety analysis report (SAR) for live-fire ranges. An RAR rather than a SAR was selected in order to gain flexibility to more closely address the safety analysis and conduct of operation needs for a live-fire range in a cost-effective manner.

  13. Vortex variable range hopping in a conventional superconducting film

    Science.gov (United States)

    Percher, Ilana M.; Volotsenko, Irina; Frydman, Aviad; Shklovskii, Boris I.; Goldman, Allen M.

    2017-12-01

    The behavior of a disordered amorphous thin film of superconducting indium oxide has been studied as a function of temperature and magnetic field applied perpendicular to its plane. A superconductor-insulator transition has been observed, though the isotherms do not cross at a single point. The curves of resistance versus temperature on the putative superconducting side of this transition, where the resistance decreases with decreasing temperature, obey two-dimensional Mott variable-range hopping of vortices over wide ranges of temperature and resistance. To estimate the parameters of hopping, the film is modeled as a granular system and the hopping of vortices is treated in a manner analogous to hopping of charges. The reason the long-range interaction between vortices over the range of magnetic fields investigated does not lead to a stronger variation of resistance with temperature than that of two-dimensional Mott variable-range hopping remains unresolved.

  14. Local adaptation at range edges: comparing elevation and latitudinal gradients.

    Science.gov (United States)

    Halbritter, A H; Billeter, R; Edwards, P J; Alexander, J M

    2015-10-01

    Local adaptation at range edges influences species' distributions and how they respond to environmental change. However, the factors that affect adaptation, including gene flow and local selection pressures, are likely to vary across different types of range edge. We performed a reciprocal transplant experiment to investigate local adaptation in populations of Plantago lanceolata and P. major from central locations in their European range and from their latitudinal and elevation range edges (in northern Scandinavia and Swiss Alps, respectively). We also characterized patterns of genetic diversity and differentiation in populations using molecular markers. Range-centre plants of P. major were adapted to conditions at the range centre, but performed similarly to range-edge plants when grown at the range edges. There was no evidence for local adaptation when comparing central and edge populations of P. lanceolata. However, plants of both species from high elevation were locally adapted when compared with plants from high latitude, although the reverse was not true. This asymmetry was associated with greater genetic diversity and less genetic differentiation over the elevation gradient than over the latitudinal gradient. Our results suggest that adaptation in some range-edge populations could increase their performance following climate change. However, responses are likely to differ along elevation and latitudinal gradients, with adaptation more likely at high-elevation. Furthermore, based upon these results, we suggest that gene flow is unlikely to constrain adaptation in range-edge populations of these species. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  15. Geographic range size and extinction risk assessment in nomadic species.

    Science.gov (United States)

    Runge, Claire A; Tulloch, Ayesha; Hammill, Edd; Possingham, Hugh P; Fuller, Richard A

    2015-06-01

    Geographic range size is often conceptualized as a fixed attribute of a species and treated as such for the purposes of quantification of extinction risk; species occupying smaller geographic ranges are assumed to have a higher risk of extinction, all else being equal. However many species are mobile, and their movements range from relatively predictable to-and-fro migrations to complex irregular movements shown by nomadic species. These movements can lead to substantial temporary expansion and contraction of geographic ranges, potentially to levels which may pose an extinction risk. By linking occurrence data with environmental conditions at the time of observations of nomadic species, we modeled the dynamic distributions of 43 arid-zone nomadic bird species across the Australian continent for each month over 11 years and calculated minimum range size and extent of fluctuation in geographic range size from these models. There was enormous variability in predicted spatial distribution over time; 10 species varied in estimated geographic range size by more than an order of magnitude, and 2 species varied by >2 orders of magnitude. During times of poor environmental conditions, several species not currently classified as globally threatened contracted their ranges to very small areas, despite their normally large geographic range size. This finding raises questions about the adequacy of conventional assessments of extinction risk based on static geographic range size (e.g., IUCN Red Listing). Climate change is predicted to affect the pattern of resource fluctuations across much of the southern hemisphere, where nomadism is the dominant form of animal movement, so it is critical we begin to understand the consequences of this for accurate threat assessment of nomadic species. Our approach provides a tool for discovering spatial dynamics in highly mobile species and can be used to unlock valuable information for improved extinction risk assessment and conservation

  16. Petrology of arkosic sandstones, Pennsylvanian Minturn Formation and Pennsylvanian and Permian Sangre de Cristo Formation, Sangre de Cristo Range, Colorado - data and preliminary interpretations

    Science.gov (United States)

    Lindsey, D.A.

    2000-01-01

    This report describes the mineral and chemical composition of immature, arkosic sandstones of the Pennsylvanian Minturn and Pennsylvanian and Permian Sangre de Cristo Formations, which were derived from the Ancestral Rocky Mountains. Located in the Sangre de Cristo Range of southern Colorado, the Minturn and Sangre de Cristo Formations contain some of the most immature, sodic arkoses shed from the Ancestral Rocky Mountains. The Minturn Formation was deposited as fan deltas in marine and alluvial environments; the Sangre de Cristo Formation was deposited as alluvial fans. Arkoses of the Minturn and Sangre de Cristo Formations are matrix-rich and thus may be properly considered arkosic wackes in the terminology of Gilbert (Williams and others, 1954). In general, potassium feldspar and plagioclase are subequal in abundance. Arkose of the Sangre de Cristo Formation is consistently plagioclase-rich; arkose from the Minturn Formation is more variable. Quartz and feldspar grains are accompanied by a few percent rock fragments, consisting mostly of intermediate to granitic plutonic rocks, gneiss, and schist. All of the rock fragments seen in sandstone are present in interbedded conglomerate, consistent with derivation from a Precambrian terrane of gneiss and plutonic rocks much like that exposed in the present Sangre de Cristo Range. Comparison of mineral and major oxide abundances reveals a strong association of detrital quartz with SiO2, all other detrital minerals (totaled) with Al2O3, potassium feldspar plus mica with K2O, and plagioclase with Na2O. Thus, major oxide content is a good predictor of detrital mineralogy, although contributions from matrix and cement make these relationships less than perfect. Detrital minerals and major oxides tend to form inverse relationships that reflect mixtures of varying quantities of minerals; when one mineral is abundant, the abundance of others declines by dilution. In arkose of the Minturn and Sangre de Cristo Formations, the

  17. Range and Battery Depletion Concerns with Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Tomio Miwa

    2017-01-01

    Full Text Available This study investigates the effects of the range of a battery electric vehicle (EV by using questionnaire data. The concern about battery depletion changes according to charging station deployment. Firstly, the methodology for deriving the probabilistic distribution of the daily travel distance is developed, which enables us to analyze people’s tolerance of the risk of battery depletion. Secondly, the desired range of an EV is modeled. This model considers the effect of changing charging station deployment and can analyze the variation in the desired range. Then, the intention of a household to purchase an EV is analyzed by incorporating range-related variables. The results show that people can live with a risk of battery depletion of around 2% to 5%. The deployment of charging stations at large retail facilities and/or workplace parking spaces reduces the desired range of an EV. Finally, the answers to the questionnaire show that the probability of battery depletion on a driving day has little effect on the intention to purchase an EV. Instead, people tend to evaluate the range by itself or directly compare it with their desired range.

  18. Propagation in a waveguide with range-dependent seabed properties.

    Science.gov (United States)

    Holland, Charles W

    2010-11-01

    The ocean environment contains features affecting acoustic propagation that vary on a wide range of time and space scales. A significant body of work over recent decades has aimed at understanding the effects of water column spatial and temporal variability on acoustic propagation. Much less is understood about the impact of spatial variability of seabed properties on propagation, which is the focus of this study. Here, a simple, intuitive expression for propagation with range-dependent boundary properties and uniform water depth is derived. It is shown that incoherent range-dependent propagation depends upon the geometric mean of the seabed plane-wave reflection coefficient and the arithmetic mean of the cycle distance. Thus, only the spatial probability distributions (pdfs) of the sediment properties are required. Also, it is shown that the propagation over a range-dependent seabed tends to be controlled by the lossiest, not the hardest, sediments. Thus, range-dependence generally leads to higher propagation loss than would be expected, due for example to lossy sediment patches and/or nulls in the reflection coefficient. In a few instances, propagation over a range-dependent seabed can be calculated using range-independent sediment properties. The theory may be useful for other (non-oceanic) waveguides.

  19. An image guided algorithm for range map super-resolution

    Science.gov (United States)

    Lei, Jieyu; Han, Shaokun; Xia, Wenze; Wang, Liang; Zhai, Yu

    2018-01-01

    Three-dimensional imaging is increasingly becoming important in a number of applications that observe and analyze real-world environments. Range sensors, such as flash imaging Lidar and Time-of-flight camera, which can deliver high accuracy range measurement images, but are limited by the low resolution. To overcome this limitation, this paper shows the benefit of multimodal sensor system, combining a low-resolution range sensor with a high-resolution optical sensor, in order to provide a high-resolution, low-noise range image of the scene. First, an extrinsic calibration algorithm is used to align the range map with optical image. Then, an image-guided algorithm is proposed to solve the super-resolution optimization problem. This algorithm using the Markov Random Field framework. It defines an energy function that combines a standard quadratic data term and a regularizing term with the weighting factors that relate optical image edges to range map edges. Experiments on synthetic and real data are provided and analyzed to validate this method. The result confirms that the quality of the estimated high-resolution range map is improved. This work can be extended for video super-resolution with the consideration of temporal coherence.

  20. Quaternary climate change and the geographic ranges of mammals.

    Science.gov (United States)

    Davies, T Jonathan; Purvis, Andy; Gittleman, John L

    2009-09-01

    A species' range can be a proxy for its ecological well-being. Species with small and shrinking range distributions are particularly vulnerable to extinction. Future climate change scenarios are predicted to affect species' geographical extents, but data on how species' distributions respond to changing climate are largely anecdotal, and our understanding of the determinants and limits to species geographic ranges is surprisingly poor. Here we show that mammal species in more historically variable environments have larger geographical ranges. However, the relationship between range size and long-term climate trends cannot be explained by variation in our estimates of habitat specificity. We suggest that large oscillations in Quaternary temperatures may have shaped the contemporary distribution of range sizes via the selective extirpation of small-ranged species during glacial expansion and/or recolonization by good dispersers after glacial retreats. The effect of current climate change on species' distributions and extinctions may therefore be determined by the geographical coincidence between historical and future climate scenarios, the "mesh size" of the extinction/dispersal filter imposed by past climate change, and whether similar ecological and evolutionary responses to historical climatic change are appropriate in an increasingly transformed and fragmented landscape.