Halogen systematics in the Mallik 5L-38 gas hydrate production research well,Northwest Territories,Canada: Implications for the origin of gas hydrates under terrestrial permafrost conditions     

Hitoshi Tomaru  Udo Fehn  Zunli Lu  Ryo Matsumoto 《Applied Geochemistry》2007

The authors report here halogen concentrations in pore waters and sediments collected from the Mallik 5L-38 gas hydrate production research well, a permafrost location in the Mackenzie Delta, Northwest Territories, Canada. Iodine and Br are commonly enriched in waters associated with CH₄, reflecting the close association between these halogens and source organic materials. Pore waters collected from the Mallik well show I enrichment, by one order of magnitude above that of seawater, particularly in sandy layers below the gas hydrate stability zone (GHSZ). Although Cl and Br concentrations increase with depth similar to the I profile, they remain below seawater values. The increase in I concentrations observed below the GHSZ suggests that I-rich fluids responsible for the accumulation of CH₄ in gas hydrates are preferentially transported through the sandy permeable layers below the GHSZ. The Br and I concentrations and I/Br ratios in Mallik are considerably lower than those in marine gas hydrate locations, demonstrating a terrestrial nature for the organic materials responsible for the CH₄ at the Mallik site. Halogen systematics in Mallik suggest that they are the result of mixing between seawater, freshwater and an I-rich source fluid. The comparison between I/Br ratios in pore waters and sediments speaks against the origin of the source fluids within the host formations of gas hydrates, a finding compatible with the results from a limited set of ¹²⁹I/I ratios determined in pore waters, which gives a minimum age of 29 Ma for the source material, i.e. at the lower end of the age range of the host formations. The likely scenario for the gas hydrate formation in Mallik is the derivation of CH₄ together with I from the terrestrial source materials in formations other than the host layers through sandy permeable layers into the present gas hydrate zones.  相似文献   

Rainfall on the Meghalaya plateau in northeastern India—one of the rainiest places in the world     

Fumie Murata  Taiichi Hayashi  Jun Matsumoto  Haruhisa Asada 《Natural Hazards》2007,42(2):391-399

Monthly and daily variations in rainfall over Cherapunjee and Mawsynram on the Meghalaya plateau of northeastern India are analysed. Cherapunjee and Mawsynram are well known as two of the places with the heaviest rainfall in the world. The daily rainfall variation is attributed to the influence of synoptic scale disturbances, with a periodicity of 10–20 days, and the orographic interaction. The annual and monthly highest rainfalls over Cherapunjee during the 31 years from 1973 to 2003 were much larger than mean values.  相似文献   

A psychological effect of having a potentially viable sequestration strategy     

Katsumi Matsumoto 《Carbon balance and management》2006,1(1):1-2

We are pleased to announce the launch of Carbon Balance and Management, a new online open access journal published by BioMed Central.  相似文献   

Possible Coseismic Large-scale Landslide off the Northern Coast of Papua New Guinea in July 1998: Geophysical and Geological Results from SOS Cruises     

Takeshi Matsumoto  David R. Tappin 《Pure and Applied Geophysics》2003,160(10-11):1923-1943

— The epicentral area of the 1998 Papua New Guinea Earthquake and Tsunami off Sissano Lagoon, northern coast of Papua New Guinea (M=7.1; 17 July, 1998) was surveyed by the Research Vessel Kairei in January 1999. Precise bathymetric survey by use of SEABEAM-2112 and other geophysical surveys (bottom reflectivity, sub-bottom profiling, surface ship gravity and geomagnetic surveys) were carried out and four piston core samples were collected during the nine days' survey. The area was also surveyed by use of the Japanese deep sea research ROV Dolphin-3K and research submersible Shinkai-2000 after the regional geophysical survey, in order to locate the possible seismic faults and/or underwater landslides as the source of tsunami and to study the process which took place off Sissano Lagoon and the driving force of the event. The study area is characterised by substantial fan sediment supply from Sissano Lagoon. Straight small-scale submarine canyons and valleys are eroding the shelf slope constructed by the fan sediment. Topographic features of arcuate slumps caused by landslides are recognised at numerous sites of the study area. Most of them are old and the most recent is located 25 km northeast off the Sissano Lagoon. Two major topographic depressions on the shelf were located off Sissano Lagoon. The western is a depression of about 10-km width and the eastern is a meandering deep-sea canyon. Amphitheatre topographic features with slumps caused by landslides that were discovered by Kairei's cruise were extensively surveyed in the study area. Six dives by Dolphin-3K and seven dives by Shinkai-2000 revealed that a fresh crack of about 15 km in total length is located along the slope of the amphitheatre. The crack is apparently the upper slope of a large-scale slumping on the amphitheatre, characterised by tensional stress on it. The easternmost part of the fresh crack is accompanied by living chemosynthetic organisms such as mussels and tube worms. The chemosynthetic community is apparently associated with cold seepage along the crack suggesting that the crack was constructed very recently. The areas other than the crack were rather old with bioturbation.  相似文献   

Geochemical Process of Gas Hydrate Formation in the Nankai Trough Based on Chloride and Isotopic Anomalies in Interstitial Water   总被引：2，自引：0，他引：2  

Hitoshi Tomaru    Ryo Matsumoto    Hailong Lu  Takashi Uchida 《Resource Geology》2004,54(1):45-51

Abstract: Interstitial water expelled from gas hydrate-bearing and -free sediments in the Nankai Trough are analyzed in terms of Cl-, SO₄²-, δ¹⁸O and δD. The baselines for the Cl- concentration and δ¹⁸O value are close to seawater values (530 mM and 0%), indicating that the interstitial water is of seawater origin. The δD values decrease with depth, implying isotopic exchange of hydrogen between upwelling biogenic methane depleted in D and interstitial water. The Cl- concentrations in gas hydrate-bearing sediments are anomalously low, while the δ¹⁸O and δD values are both high, suggesting that the water forming these gas hydrates was poor in Cl- and enriched in ¹⁸O and D during gas hydrate formation. Calculation of the gas hydrate saturations using Cl "and δ¹⁸O anomalies gives results of up to 80 % in sand, and shows that the δ¹⁸O baseline is not consistent with the Cl" baseline. The δ¹⁸O baseline increases by +1% in gas hydrate-free clay and silt. This is considered to be caused by clustering of water molecules after gas hydrate dissociation in response to the upward migration of the base of gas hydrate stability, as indicated by the presence of a double bottom-simulating reflector at this site. The water clusters enriched in ¹⁸O are responsible for the increase in the δ¹⁸O baseline with normal Cl". The abrupt shallowing of the base of gas hydrate stability may induce the dissociation of gas hydrates and the accumulation of gases in the new stability zone, representing a geological process that increases gas hydrate saturation.  相似文献   

Preface     

Ryo Matsumoto 《Resource Geology》2004,54(1):1-2

Editorial Board for the Special Issue on "Gas Hydrate in Nankai Trough, Japan"
Takashi U chida (JAPEX Research Center, Japan Petroleum Exploration Co., Ltd.), Amane W aseda (JAPEX Research Center, Japan Petroleum Exploration Co., Ltd.), Naotatsu S hikazono (Department of Applied Chemistry, Keio University), Yutaka A oki (JGI Inc.) and Yoshihiro T suji (Technology Research Center, Japan Oil,
Gas and Metals National Corporation)  相似文献   

Alignment silkworms as seismic animal anomalous behavior (SAAB) and electromagnetic model of a fault: a theory and laboratory experiment     

池谷元伺  松本裕史  黄清华 《地震学报(英文版)》1998,11(3):365-374

Ａｌｉｇｎｍｅｎｔｓｉｌｋｗｏｒｍｓａｓｓｅｉｓｍｉｃａｎｉｍａｌａｎｏｍａｌｏｕｓｂｅｈａｖｉｏｒ（ＳＡＡＢ）ａｎｄｅｌｅｃｔｒｏｍａｇｎｅｔｉｃｍｏｄｅｌｏｆａｆａｕｌｔ：ａｔｈｅｏｒｙａｎｄｌａｂｏｒａｔｏｒｙｅｘｐｅｒｉｍｅｎｔＭＯＴＯ...  相似文献   

Mineralogy and hydrogen isotope geochemistry of clay minerals in the Ohnuma geothermal area,Northeastern Japan     

Katsumi Marumo  Keinosuke Nagasawa  Yoshimasu Kuroda 《Earth and Planetary Science Letters》1980,47(2):255-262

Mineralogical and hydrogen isotopic studies have been made on clay minerals occurring in the Ohnuma geothermal area, northeastern Japan. Here, clay minerals such as smectite, kaolinite, dickite, sericite, and chlorite were formed by hydrothermal alteration of Miocene rocks. A chemical equilibrium can be assumed to be attained from the fact that the amount of expandable layer in the interstratified chlorite/smectite decreases and the polytype of sericite changes from 1M to 2M₁ with increasing depth and temperature. The hydrogen isotopic composition (D/H) of the clay minerals is lighter than that of the geothermal and local meteoric waters by about 20–40‰. The hydrogen isotopic fractionation factors α_{mineral-water} are as follows: 0.972–0.985 for kaolinite and dickite, 0.973–0.977 for sericite, and 0.954–0.987 for chlorite. In the temperature range from 100 to 250°C, the hydrogen isotopic fractionation factors between these minerals and water are not sensitive to the temperature. α_{chlorite-water} depends on the kind of octahedrally coordinated cations which lie close to the hydroxyl groups; it becomes large with an increase of Mg content of chlorite.  相似文献   

Study on the compositional dependence of the apparent partition coefficient of iron and magnesium between coexisting garnet and clinopyroxene solid solution     

Yasutami Oka  Takashi Matsumoto 《Contributions to Mineralogy and Petrology》1974,48(2):115-121

Compositional dependence of apparent partition coefficient of iron and magnesium between coexisting garnet and clinopyroxene from Mt. Higasiakaisi is studied by means of a multicomponent regular solution model. It is shown that garnet and clinopyroxene solid solutions are positively non-ideal, and the non-ideal parameters according to the symmetric regular solution model are 2.58 kcal and 2.39 kcal, respectively, assuming the equilibration temperature of the mass to be 550° C.Notations a _i ^h activity of component i in phase h - _ij interaction parameter of component i and j in a solid solution - _i activity coefficient of component i - X _i mole fraction of component i - K partition coefficient of Fe and Mg between coexisting garnet and clinopyroxene - K apparent partition coefficient of Fe and Mg between coexisting garnet and clinopyroxene - G ⁰ difference in free energy of the partition reaction - H ⁰ difference in enthalpy of the partition reaction - S ⁰ difference in entropy of the partition reaction - R gas constant - G garnet - Alm almandine component - Py pyrope component - Gr grossular component - Sp spessartine component - CPx clinopyroxene - Hd hedenbergite component - Di diopside component - Jd jadeite component - Ts Tschermac's molecule component Deceased on April 17, 1974.  相似文献   

High-pressure decompositions in manganese silicates and their geophysical implications     

Eiji Ito  Takashi Matsumoto  Naoto Kawai 《Physics of the Earth and Planetary Interiors》1974,8(3):241-245

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