Mineralogy and lithology of the Upper Cretaceous Niobrara Formation determined by hyperspectral core imaging

2020 ◽  
Vol 57 (2) ◽  
pp. 121-143
Author(s):  
Justin E. Birdwell ◽  
Lionel C. Fonteneau ◽  
Brigette A. Martini
Keyword(s):  
Upper Cretaceous ◽  
Imaging System ◽  
Detailed Examination ◽  
Limited Range ◽  
Short Wave ◽  
Niobrara Formation ◽  
Petroleum Systems ◽  
Textural Data ◽  
Infrared Wavelengths ◽  
General Correspondence

Sections of the Upper Cretaceous (Coniacian to Campanian) Niobrara Formation in two cores from Kansas and Colorado, the Amoco Rebecca Bounds and USGS Portland 1, respectively, were examined by hyperspectral core imaging and analysis. A spectral imaging system combining high-resolution photography (50 μm), 3D laser profiling (20 μm), and near-visible + short-wave infrared reflectance spectroscopy (wavelengths from 450 to 2500 nm, 500 μm pixel size) was applied to these cores to provide spectral and textural data facilitating creation of continuous mineral and lithology class maps. In addition, compositing of pixel-based results to group pixels to create mineralogical and lithological logs (0.5-ft resolution) was performed to facilitate comparisons to other geochemical datasets. The results show general correspondence in trends identified by previous geochemistry studies, with some exceptions due to instrumental limitations related to low reflectance of some rock intervals and the limited range of infrared wavelengths examined. This study provides a cursory overview of an extensive dataset meant to demonstrate the utility of hyperspectral core scanning to studies of mudrocks in petroleum systems as well as the kinds of information this technique can provide for detailed examination of stratigraphic features in sedimentary systems more generally.

The first record of spiral coprolites from the Dinosaur Park Formation (Judith River Group, Upper Cretaceous) southern Alberta, Canada

1995 ◽  
Vol 69 (6) ◽  
pp. 1191-1194 ◽  
Author(s):  
Clive E. Coy
Keyword(s):  
North America ◽  
Upper Cretaceous ◽  
First Record ◽  
Niobrara Formation ◽  
Southern Alberta ◽  
Dinosaur Park Formation

Spiral coprolites from the Upper Cretaceous of North America are poorly known. Enterospirae (fossilized intestines) reported from the Upper Cretaceous Niobrara Formation of western Kansas (Stewart, 1978) were disputed by McAllister (1985), who felt they represented spiral coprolites similar to those described from the Permian by Neumayer (1904). Previously described coprolites from the Upper Cretaceous of Alberta are small, unstructured, ellipsoidal forms thought to derive from a crocodilian or terrestrial, carnivorous reptile of necrophagic or piscivorous habits (Waldman, 1970; Waldman and Hopkins, 1970).

scholarly journals City-Scale Distance Sensing via Bispectral Light Extinction in Bad Weather

2020 ◽  
Vol 12 (9) ◽  
pp. 1401
Author(s):  
Dong Zhao ◽  
Yuta Asano ◽  
Lin Gu ◽  
Imari Sato ◽  
Huixin Zhou
Keyword(s):  
Extinction Coefficient ◽  
Near Infrared ◽  
Imaging System ◽  
Weather Conditions ◽  
Light Extinction ◽  
Selection Strategy ◽  
Infrared Wavelengths ◽  
The Difference ◽  
Bad Weather ◽  
Almost All

In this paper, we propose a novel city-scale distance sensing algorithm based on atmosphere optics. The suspended particles, especially in bad weather, would attenuate the light at almost all wavelengths. Observing this fact and starting from the light scattering mechanism, we derive a bispectral distance sensing algorithm by leveraging the difference of extinction coefficient between two specifically selected near infrared wavelengths. The extinction coefficient of the atmosphere is related to both wavelength and meteorological conditions, also known as visibility, such as the fog and haze day. To account for different bad weather conditions, we explicitly introduce visibility into our algorithm by incorporating it into the calculation of extinction coefficient, making our algorithm simple yet effective. To capture the data, we build a bispectral imaging system that is able to take a pair of images with a monochrome camera and two narrow band-pass filters. We also present a wavelength selection strategy that allows us to accurately sense distance regardless of material reflectance and texture. Specifically, this strategy determines two distinct near infrared wavelengths by maximising the extinction coefficient difference while minimizing the influence of building’s reflectance variance. The experiments empirically validate our model and its practical performance on the distance sensing for the city-scale buildings.

Galvanic replacement synthesis of multi-branched gold nanocrystals for photothermal cancer therapy

2020 ◽  
Vol 8 (25) ◽  
pp. 5491-5499
Author(s):  
Dewei Zhu ◽  
Yang Liu ◽  
Maixian Liu ◽  
Xin Liu ◽  
Paras N. Prasad ◽  
...  
Keyword(s):  
Near Infrared ◽  
Short Wave ◽  
Localized Surface Plasmon ◽  
Galvanic Replacement ◽  
Gold Nanocrystals ◽  
Photothermal Heating ◽  
Cervical Cancer Cells ◽  
Infrared Wavelengths ◽  
Human Cervical Cancer Cells ◽  
Human Cervical Cancer

Au nanostars with tunable arm length and broad tunable localized surface plasmon resonance absorbance across near-infrared to short-wave infrared wavelengths effectively ablate human cervical cancer cells through photothermal heating.

scholarly journals Establishment of AIRS Climate-Level Radiometric Stability using Radiance Anomaly Retrievals of Minor Gases and SST

2020 ◽  
Author(s):  
L. Larrabee Strow ◽  
Sergio DeSouza-Machado
Keyword(s):  
Surface Temperature ◽  
Brightness Temperature ◽  
Optimal Estimation ◽  
Detailed Examination ◽  
Short Wave ◽  
Climate Trend ◽  
Temperature Anomalies ◽  
Temperature Trends ◽  
Multiplicative Shift ◽  
Geophysical Anomalies

Abstract. Temperature, H2O, and O3 profiles, as well as CO2, N2O, CH4, CFC12, and SST scalar anomalies are computed using a clear subset of AIRS observations over ocean for the first 16-years of NASA's EOS-AQUA AIRS operation. The AIRS Level 1c radiances are averaged over 16 days and 40 equal-area zonal bins and then converted to brightness temperature anomalies. Geophysical anomalies are retrieved from the brightness temperature anomalies using a relatively standard optimal estimation approach. The CO2, N2O, CH4, and CFC12 anomalies are derived by applying a vertically uniform multiplicative shift to each gas in order to obtain an estimate for the ngas mixing ratio. The minor gas anomalies are compared to the NOAA ESRL in-situ values and used to estimate the radiometric stability of the AIRS radiances. Similarly the retrieved SST anomalies are compared to the SST values used in the ERA-Interim reanalysis and to NOAA's OISST SST product. These inter-comparisons strongly suggest that many AIRS channels are stable to better than 0.02 to 0.03 K/Decade, well below climate trend levels, indicating that the AIRS blackbody is not drifting. However, detailed examination of the anomaly retrieval residuals (observed minus computed) show various small unphysical shifts that correspond to AIRS hardware events (shutdowns, etc.). Some examples are given highlighting how the AIRS radiances stability could be improved, especially for channels sensitive to N2O and CH4. The AIRS short wave channels exhibit larger drifts that make them unsuitable for climate trending, and they are avoided in this work. The AIRS Level 2 surface temperature retrievals only use short wave channels. We summarize how these short wave drifts impacts recently published comparisons of AIRS surface temperature trends to other surface climatologies.

High Spatial and High Spectral Resolution FTIR Spectroscopic Imaging of Biological Materials

1997 ◽  
Vol 3 (S2) ◽  
pp. 831-832
Author(s):  
E.N. Lewis ◽  
L.H. Kidder ◽  
I.W. Levin
Keyword(s):  
Spectral Resolution ◽  
Imaging System ◽  
Spectroscopic Imaging ◽  
Quantitative Information ◽  
High Spectral Resolution ◽  
Spectroscopic Techniques ◽  
Structure And Dynamics ◽  
Spatial Domains ◽  
Infrared Wavelengths

Infrared spectroscopy has been used to probe a variety of biological systems including for example, the determination of diseased states and the investigation of foreign inclusions in biologicals. The technique generates qualitative and quantitative information on the structure and dynamics of samples, including lipids, proteins, and non-biological constituents. The coupling of imaging modalities with spectroscopic techniques adds a new dimension to sample analysis in both the spectroscopic and spatial domains. Using a spectroscopic imaging system that incorporates a step-scan interferometer, microscope, and infrared sensitive arrays, we have investigated a variety of biological samples. This seamless combination of spectroscopy for molecular analysis with the power of visualization generates chemically specific images while simultaneously obtaining high resolution spectra for each detector pixel. The spatial resolution of the images approaches the diffraction limit for mid-infrared wavelengths, while the spectral resolution is determined by the interferometer and can be 4 cm−1 or higher.

Eastern Boulder-Weld fault zone, Colorado: A gravity slide with pop-up structures

2020 ◽  
Vol 57 (3) ◽  
pp. 177-198
Author(s):  
Richard H. Groshong ◽  
Ken Kittleson
Keyword(s):  
Fault Zone ◽  
Cross Sections ◽  
Upper Cretaceous ◽  
Sedimentary Rocks ◽  
Detailed Examination ◽  
Contour Map ◽  
Pierre Shale ◽  
Structural Style ◽  
Transport Direction ◽  
Gravity Slide

The Boulder-Weld fault zone, located southeast of Boulder, Colorado, is about 10 km (6 mi) wide, 34 km (21 mi) long, and involves at least 335 m (1100 ft) of upper Cretaceous sedimentary rocks. It affects the Cretaceous upper Pierre Shale, Fox Hills Sandstone, and the coal–bearing lower Laramie Formation. This study is a detailed examination of the eastern portion of the fault zone which consists of undisturbed areas separated by three long, narrow, fault-bounded uplifts that have received a variety of interpretations over the years. The fault zone geometry is determined from 21 closely spaced cross sections that use more subsurface data than previous studies, incorporate the elevations of the major economic coal seam derived from a published composite structure-contour map, and are area balanced using area-depth-strain (ADS) analysis. The most common structural style is a pop-up structure in which the uplifts are bounded on both sides by reverse faults. At larger-displacement the pop-ups are at the tip of the ramp and a second fault has formed close to the base of the ramp. A few sections show simple ramp anticlines developed above listric thrusts. The lower detachment for all structures is the distinctive Kp2 marker in the upper Pierre Shale. ADS analysis of the best-controlled uplifts shows that the uplifts are area balanced and confirms the lower detachment to be near Kp2. The structures are interpreted to have formed as a gravity slide because they formed in a break-back sequence, a characteristic of gravity gliding, and because the transport direction is approximately down the current southeast dip of the Kp2 detachment.

Bitumen geochemistry and producibility in the Upper Cretaceous Niobrara Formation shale oil play

AAPG Bulletin ◽  
2021 ◽  
Vol 105 (10) ◽  
pp. 2017-2039
Author(s):  
Yuanjia Han ◽  
Brian Horsfield ◽  
Nicolaj Mahlstedt ◽  
Heather LaReau
Keyword(s):  
Upper Cretaceous ◽  
Shale Oil ◽  
Niobrara Formation

An Investigation of Free Rolling Resistance at Light Loads

1982 ◽  
Vol 104 (3) ◽  
pp. 376-381
Author(s):  
P. H. Markho
Keyword(s):  
Oscillation Amplitude ◽  
Rolling Resistance ◽  
Detailed Examination ◽  
Limited Range ◽  
Gradual Transition ◽  
Experimental Conditions ◽  
Load Range ◽  
Air Resistance ◽  
En 31 ◽  
Bearing Ball

This paper presents the results of an investigation into the resistance to free rolling, under light loads, of a ball bearing ball on a flat track of unhardened En 31 steel using a pendulum arrangement in partial vacuum (5 – 50 Pa). The effect of air resistance (from experiments conducted in air) is demonstrated and results of tests at different frequencies and loads are presented. These include estimates of the effective hysteresis loss factor and of the coefficient of rolling resistance. A detailed examination of the amplitude decay curves shows that the damping, under the experimental conditions described, (i) can be represented neither by the Coulomb nor the viscous models; (ii) is practically independent of frequency (within the limited range possible with the apparatus); (iii) is appreciably dependent on contact load and oscillation amplitude, especially at the higher end of the load range investigated where a gradual transition to plastic behaviour is evident.

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