The brine depth of the Khorat Basin in Thailand as indicated by high-resolution Br profile

AbstractBromine contents of a 17-cm halite core from drilling hole of K203 in the Khorat Basin were analysed at 1 cm intervals (17 samples in total). The Br contents range from 99 to 184 ppm with a rapid variation. The K/Mg ratios of halite samples are tens of times higher than those of primary halite fluid inclusions. There is no positive correlation between Mg and Br contents, suggesting that fluid inclusions impose very little or negligible influence on Br contents of halites. The Br contents are not controlled by potash minerals either because the SEM examination shows no potash minerals and there is no relationship between K and Br contents. The Br contents of halite are thus primarily controlled by the Br concentrations of parent brines. The rapid variation of Br contents of halite within this section suggests a shallow saline pan wherein the giant Khorat evaporites were formed. This is contradictory to previous Br profiles of the Lower Salt Member which showed relatively stable and continuously increasing trends. The shallow saline pan model evidenced by high-resolution Br profile is consistent with sedimentary facies and salt mineral textures.

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Land cover change dominates decadal trends of biogenic volatile organic compound (BVOC) emission in China

10.5194/acp-2020-28 ◽

2020 ◽

Author(s):

Hui Wang ◽

Qizhong Wu ◽

Alex B. Guenther ◽

Xiaochun Yang ◽

Lanning Wang ◽

...

Keyword(s):

Land Cover ◽

Land Cover Change ◽

Correlation Coefficients ◽

Anthropogenic Sources ◽

The South ◽

High Positive Correlation ◽

Positive Correlation ◽

Isoprene Emission ◽

Increasing Trends ◽

The Impact

Abstract. Satellite observations reveal that China has been leading the global greening trend in the past two decades. We assessed the impact of land cover change on total BVOC emission in China during 2001–2016 and found a significant increasing trend of 1.09 % yr−1 with increases of 1.35, 1.25 and 1.43 % yr−1 for isoprene, monoterpenes and sesquiterpenes, respectively. Comparison of different scenarios showed that vegetation change is the main driver of BVOC emission change in China. Considerable heterogeneity was observed on regional scales, with the highest increasing trends of BVOC emission found in the Qinling Mountains and in the south of China. The BVOC emission for the year 2016 in these two regions was enhanced by 61.89 and 67.64 % compared to that of 2001, respectively. We compared the long-term HCHO vertical columns (VC) from the satellite-based Ozone Monitoring Instrument (OMI) with the estimation of isoprene emission in summer. The results showed statistically significant positive correlation coefficients over the regions with high vegetation cover fractions. In addition, the isoprene emission and HCHO VC both showed statistically significant increasing trends in the south of China where these two variables have high positive correlation coefficients. This result supports our estimation of the variability and trends of BVOC emission in China. Although anthropogenic sources comprise ∼63 % NMVOC emissions in China, the continued increase of BVOC will enhance the importance of considering BVOC when making policies for controlling ozone pollution in China along with ongoing efforts to reduce anthropogenic emissions.

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An integrated high-resolution geophysical and geologic visualization of a Lake Bonneville shoreline deposit (Utah, USA)

Interpretation ◽

10.1190/int-2018-0116.1 ◽

2019 ◽

Vol 7 (2) ◽

pp. T265-T282 ◽

Cited By ~ 3

Author(s):

Katelynn M. Smith ◽

John H. McBride ◽

Stephen T. Nelson ◽

R. William Keach ◽

Samuel M. Hudson ◽

...

Keyword(s):

High Resolution ◽

Late Pleistocene ◽

Depositional Environment ◽

Three Dimensional ◽

Sedimentary Facies ◽

Basin And Range ◽

Basin And Range Province ◽

Lake Bonneville ◽

Depositional Processes ◽

Gravel Bar

Pilot Valley, located in the eastern Basin and Range, Western Utah, USA, contains numerous shorelines and depositional remnants of Late Pleistocene Lake Bonneville. These remnants present excellent ground-penetrating radar (GPR) targets due to their coherent stratification, low-clay, low-salinity, and low moisture content. Three-dimensional GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters, and when combined with detailed outcrop characterization, it provides an in-depth look at the architecture of these deposits. On the western side of Pilot Valley, a well-preserved late Pleistocene gravel bar records shoreline depositional processes associated with the Provo (or just post-Provo) shoreline period. GPR data, measured stratigraphic sections, cores, paleontological sampling for paleoecology and radiocarbon dating, and mineralogical analysis permit a detailed reconstruction of the depositional environment of this well-exposed prograding gravel bar. Contrary to other described Bonneville shoreline deposits, calibrated radiocarbon ages ranging from 16.5 to 14.3 (ka, BP) indicate that the bar was stable and active during an overall regressive stage of the lake, as it dropped from the Provo shoreline (or just post-Provo level). Our study provides a model for an ancient pluvial lakeshore depositional environment in the Basin and Range province and suggests that stable, progradational bedforms common to the various stages of Lake Bonneville are likely not all associated with periods of shoreline stability, as is commonly assumed. The high-resolution GPR visualization demonstrates the high degree of compartmentalization possible for a potential subsurface reservoir target based on ancient shoreline sedimentary facies.

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The Silurian Mulde Event and a scenario for secundo–secundo events

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593300000377 ◽

2002 ◽

Vol 93 (2) ◽

pp. 135-154 ◽

Cited By ~ 63

Author(s):

Lennart Jeppsson ◽

Mikael Calner

Keyword(s):

High Resolution ◽

Sea Level ◽

Greenhouse Effect ◽

Sedimentary Facies ◽

Sea Level Changes ◽

Secondary Result ◽

Sedimentary Succession ◽

Detailed Record ◽

Quaternary Glaciations ◽

Oceanic Model

ABSTRACTGraphic correlation using graptolites and conodonts provides a high-resolution timescale for correlating from coastal to deep oceanic sections and, thereby, also a detailed record of the sequence of changes during the Mulde Secundo-Secundo Event. That interval includes sedimentary facies otherwise unknown in older Wenlock to early Ludlow strata on Gotland. The identified sequence of changes includes a detailed record of, in order: two extinctions (Datum points 1 and 1·5); widespread deposition of carbon-rich sediments extensive enough to cause a δ13C increase of c. 4.8‰, the onset, maximum and end of a sea-level fall and rise of at least 16 m during 30 kyr; a third extinction (Datum 2); a disaster fauna; and a slow faunal recovery. Thus, a secondary result of the event was a weakened greenhouse effect triggering a glaciation: the Gannarve Glaciation (new term). The order of changes proves that regression did not cause the extinctions. Faunal and sea-level changes, as well as the sedimentary succession, fit well with predictions based on an oceanic model. Extinctions were primarily caused by a severe drop in primary planktonic productivity, causing starvation among planktonic larvae in non-coastal settings. The Grötlingbo Bentonite (new term), the thickest in the Wenlock of Gotland, was deposited across the basin shortly after Datum 2. Temporal resolution is high enough to permit some comparison with Quaternary glaciations.

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High resolution bio- and chemostratigraphic framework at the Frasnian-Famennian boundary: Implications for regional stratigraphic correlation between different sedimentary facies in South China

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2017.05.019 ◽

2019 ◽

Vol 531 ◽

pp. 108299 ◽

Cited By ~ 3

Author(s):

Jieqiong Chang ◽

Zhiqiang Bai ◽

Yuanlin Sun ◽

Yongbo Peng ◽

Shujian Qin ◽

...

Keyword(s):

High Resolution ◽

South China ◽

Sedimentary Facies ◽

Stratigraphic Correlation

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Evolution of Multistage Hydrothermal Fluids in the Luoboling Porphyry Cu-Mo Deposit, Zijinshan Ore Field, Fujian Province, China: Insights from LA-ICP-MS Analyses of Fluid Inclusions

Economic Geology ◽

10.5382/econgeo.4788 ◽

2020 ◽

Author(s):

Xiao-Yu Zhao ◽

Hong Zhong ◽

Rui-Zhong Hu ◽

Wei Mao ◽

Zhong-Jie Bai ◽

...

Keyword(s):

Fluid Inclusions ◽

Hydrothermal Systems ◽

Hydrothermal Fluids ◽

Common Source ◽

Two Phase ◽

Porphyry Cu ◽

Icp Ms ◽

High Concentrations ◽

Granodiorite Porphyry ◽

Increasing Trends

Abstract The Luoboling Cu-Mo deposit, with 1.4 million tons (Mt) Cu and 0.11 Mt Mo, is the largest porphyry deposit in the Zijinshan district of southeast China. Mineralization at Luoboling is divided into premineralization, synmineralization, and late-mineralization stages. Consistent Cs/(Na + K) ratios in fluid inclusions suggest that the mineralizing fluids originated from a common source—the Luoboling granodiorite porphyry. The absence of initial supercritical fluid inclusions and abundant coexisting vapor and brine fluid inclusions imply that the fluids exsolved at low-pressure two-phase conditions, with temperatures of 250° to 600°C and salinities of 30 to 60 wt % NaCl equiv (brines) and <10 wt % NaCl equiv (vapors). The deposit formed at ~120 to 800 bar, corresponding to the depths of ~1.2 to 3.2 km (assuming a transition from lithostatic to hydrostatic load). Metals such as Mo (up to 77 ppm), Pb (up to 8,800 ppm), Zn (up to 13,000 ppm), and Ag (up to 130 ppm) migrated mainly in brines. Although vapor inclusions have high concentrations of Cu (up to 20,000 ppm), hypersaline fluid was the major medium for Cu transport and precipitation. The successive precipitation of Mo and Cu occurred when fluids cooled to ~500°C and ~350° to 450°C, respectively. The late-stage quartz-pyrite veins with phyllic alteration were formed by Cu-rich magmatic hydrothermal fluids. The Zijinshan epithermal Cu-Au deposit and the Luoboling porphyry Cu-Mo deposit originated from independent hydrothermal systems. Nonetheless, the increasing trends of Pb, Zn, and Ag concentrations in different stage inclusions from Luoboling imply potential for distal Pb-Zn-Ag mineralization.

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High-Resolution Reconstruction of Quaternary Crustal Movement Based on Sedimentary Facies Analysis: An Example from the Oga Peninsula, Northern Japan

Journal of Sedimentary Research ◽

10.1306/102501720386 ◽

2002 ◽

Vol 72 (3) ◽

pp. 386-392 ◽

Cited By ~ 4

Author(s):

M. Shirai ◽

R. Tada

Keyword(s):

High Resolution ◽

Facies Analysis ◽

Sedimentary Facies ◽

Crustal Movement ◽

High Resolution Reconstruction ◽

Northern Japan

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On the Interpretation of QSO Absorption Lines

Symposium - International Astronomical Union ◽

10.1017/s007418090013699x ◽

1988 ◽

Vol 130 ◽

pp. 571-571

Author(s):

V. Müller ◽

J. P. Mücket ◽

S. Gottlöber ◽

H. J. Haubold

Keyword(s):

High Resolution ◽

Correlation Analysis ◽

Temperature Profile ◽

Absorption Spectra ◽

Significant Positive Correlation ◽

Radiation Transport ◽

Absorption Lines ◽

Positive Correlation ◽

Metal Absorption ◽

Inhomogeneous Temperature

OSO absorption spectra may offer a clue to the distribution of intervening matter clouds at z = 0 … 3. We tackle 1) the question of the occurrence of metal absorption lines of different ionisation levels in the same redshift systems by investigating the radiation transport through an inhomogeneous temperature profile; 2) the clustering properties of the lines of the Lyα forest by a correlation analysis of 9 published high-resolution QSO-spectra with the result of a certain contribution of metal absorption lines as well as marginally significant positive correlation regions ξ ≈ 0.3.

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Ground penetrating radar of northern lacustrine deltas

Canadian Journal of Earth Sciences ◽

10.1139/e91-175 ◽

1991 ◽

Vol 28 (12) ◽

pp. 1939-1947 ◽

Cited By ~ 155

Author(s):

Harry M. Jol ◽

Derald G. Smith

Keyword(s):

High Resolution ◽

Ground Penetrating Radar ◽

Field Research ◽

Sedimentary Facies ◽

Depositional Environments ◽

Sedimentary Environments ◽

Peat Deposits ◽

Big Picture ◽

Sand And Gravel ◽

Ground Penetrating

Ground penetrating radar (GPR) was used in several selected deltaic sedimentary environments to better understand subsurface stratigraphy and reconstruct former depositional environments. The profiles provide high-resolution, continuous subsurface data on facies thickness and depths, orientation of major sedimentary structures, postdepositional failure planes, and depth of peat deposits.Field experiments were carried out on six river deltas. Records from four of the deltas exhibit sedimentary facies; a record from one delta shows a possible slump; and records from another delta reveal the thickness and stratigraphic relationships of peat deposits. The delta types are (i) sandy, wave influenced; (ii) sandy, immature wave influenced (steeper middle and lower shoreface); (iii) sandy braided; and (iv) gravelly, fan–foreset.In areas of limited subsurface control (stratigraphic logs from drill core, cutbank exposure, or geophysical logs), radar profiles can provide ''big picture'' perspectives of the subsurface, a view only available in laterally extensive exposures. High-resolution profiles of subsurface stratigraphy and sedimentary facies from GPR provide an opportunity for geomorphologists and sedimentologists to further advance field research. Although GPR has limited success in silt and clay, results from sand and gravel deposits often reveal detailed facies assemblages.

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Observations of XCO<sub>2</sub> and XCH<sub>4</sub> with ground-based high-resolution FTS at Saga, Japan and comparisons with GOSAT products

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-8257-2015 ◽

2015 ◽

Vol 8 (8) ◽

pp. 8257-8294 ◽

Cited By ~ 1

Author(s):

H. Ohyama ◽

S. Kawakami ◽

T. Tanaka ◽

I. Morino ◽

O. Uchino ◽

...

Keyword(s):

Fourier Transform ◽

High Resolution ◽

Greenhouse Gases ◽

Near Infrared ◽

Infrared Region ◽

Fourier Transform Spectrometer ◽

Solar Absorption ◽

Average Growth ◽

Dry Air ◽

Increasing Trends

Abstract. Solar absorption spectra in the near-infrared region have been continuously acquired with a ground-based (g-b) high-resolution Fourier transform spectrometer (FTS) at Saga, Japan since July 2011. Column-averaged dry-air mole fractions of greenhouse gases were retrieved from the measured spectra for the period from July 2011 to December 2014. Aircraft measurements of CO2 and CH4 for calibrating the g-b FTS data were performed in January 2012 and 2013, and it is found that the g-b FTS and aircraft data agree to within ±0.2 %. The column-averaged dry-air mole fractions of CO2 and CH4 (XCO2 and XCH4) show increasing trends, with average growth rates of 2.3 ppm yr−1 and 9.5 ppb yr−1, respectively, during the ~ 3.5 yr of observation. We compared the g-b FTS XCO2 and XCH4 data with those derived from backscattered solar spectra in the short-wavelength infrared region measured with Thermal And Near-infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) onboard the Greenhouse gases Observing SATellite (GOSAT). Average differences between TANSO-FTS and g-b FTS data (TANSO-FTS minus g-b FTS) are 0.40 ± 2.51 ppm and −7.6 ± 13.7 ppb for XCO2 and XCH4, respectively. Using aerosol information measured with a sky radiometer at Saga, we found that the differences between the TANSO-FTS and g-b FTS data are moderately negatively correlated with aerosol optical thickness and do not depend explicitly on aerosol size. In addition, from aerosol profiles measured with lidar located right by the g-b FTS, we were able to show that cirrus clouds and tropospheric aerosols accumulated in the lower layers of the atmosphere tend to overestimate or underestimate the TANSO-FTS data.

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