SEISMIC RESONANCE: WAVELET-FREE REFLECTIVITY RETRIEVAL VIA MODIFIED CEPSTRAL DECOMPOSITION

Spectral decomposition is a proven tool in seismic interpretation, aiding interpreters to highlight channels, map temporal bed thickness and other geological discontinuities. Once seismic data is spectrally decomposed, notch patterns in the amplitude spectra are indicative of the reservoir layers thickness and/or its interval velocity. Additional cepstral decomposition will allow direct extraction of bed time-thickness or arrival time under particular reflectivity series setup. We build on these observations to establish a more generalized workflow for reflectivity retrieval method without the need to understand the details of the wavelet, provided the starting seismic is stably phased via phase correction during processing. We demonstrate reflector time and its apparent strength can be identified in a transformed seismic resonance domain resulted from a modified cepstrum analysis. In this domain, each reflector can be characterized from obvious linear hot spots. The timing and strength of those linear hot spots will reveal reflector times and scaled reflectivity coefficients. This new method is subsequently applied for thickness prediction of a target reservoir in a complex geological setting, with large thickness variations and weak impedance contrast with underlying lithology previously complicating identification of base-reservoir. In a deep-water field blind test, the sand thicknesses evaluated from this method are found to be close to true vertical thickness found in wells.

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Comparison of Interval Velocity and Inversion Velocity Usage to Build 3D Pore Pressure Models – Case Study: Ja Field, East Java Basin

Proc. Indon. Petrol. Assoc., Digital Technical Conference, 2020 ◽

10.29118/ipa20-sg-300 ◽

2020 ◽

Author(s):

J. Arief

Keyword(s):

Pressure Distribution ◽

Pore Pressure ◽

3D Models ◽

Distribution Models ◽

Blind Test ◽

Interval Velocity ◽

Color Changes ◽

Zone Depth ◽

And Inversion ◽

Pressure Analysis

Pore pressure analysis is one of the stages that needs to be done before drilling and it is intended to determine indication of overpressure zones that may endanger the drilling phase. Pore pressure analysis could be done with various variables from well and/or seismic data. This study is conducted at the JA Field, East Java Basin, and focused on the claystone interval of the Ledok – Ngrayong Formation. This study will focus on interval velocity and inversion velocity in the claystone formations, which is typically showing more sensitivity to heterogeneity in such conditions. Besides mapping overpressure zone indications, this study was conducted to determine the sensitivity of the velocity variables in analyzing pore pressure and to make 3D pore pressure distribution models, where in this study interval velocity and inversion velocity were used. In addition to using the 1D pore pressure models from Well A1, Well B2 and Well C3 as a comparison, a blind test was also carried out to validate whether the two 3D pore pressure distribution models qualitatively represented the JA Field. From the pore pressure analysis results, both on the 1D and 3D models, which were carried out based on the Eaton (1975) method, it is known that there is an indication of the overpressure zone in the Wonocolo Formation with the top of overpressure zone depth at 5900-6200 ft. The 3D pore pressure models showed the overpressure zone distribution is marked by the significant color changes tendency in the center of the study area. Qualitatively, the use of interval velocity and inversion velocity in creating the 3D models appears in the distribution of different pore pressure values. However, the two 3D pore pressure models have generally represented the JA Field pore pressure distribution as evidenced by the blind test result.

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Integrated Chip-Scale Prediction of Copper Interconnect Topography

MRS Proceedings ◽

10.1557/proc-767-f7.5 ◽

2003 ◽

Vol 767 ◽

Author(s):

Tae Park ◽

Tamba Tugbawa ◽

Hong Cai ◽

Xiaolin Xie ◽

Duane Boning

Keyword(s):

Model Development ◽

Thickness Variation ◽

Initial Condition ◽

Critical Elements ◽

Copper Interconnect ◽

Thickness Prediction ◽

Layout Geometry ◽

Layout Extraction ◽

Thickness Variations ◽

Cmp Model

AbstractIn this work, we present an integrated prediction of thickness variations in electroplating and chemical mechanical polishing (CMP) processes across an entire chip for random layouts. We achieve chip-scale prediction by first calibrating both electroplating and CMP models with experimental data using the same test mask. Using the calibrated plating model in conjunction with a discretized and binned layout extraction for a random chip layout, a prediction of plated copper topography is then performed. Finally, using the plated thickness prediction as the initial condition, the CMP model predicts the dishing and erosion across the chip. Layout geometry extraction for each discretized region of a chip as well as layout parameter manipulation and model output integration are all critical elements, in addition to the model development itself, enabling the integrated chip-scale prediction of final copper interconnect thickness variation.

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Regional geothermal aquifer architecture of the fluvial Lower Cretaceous Nieuwerkerk Formation – a palynological analysis

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/njg.2017.23 ◽

2017 ◽

Vol 96 (4) ◽

pp. 319-330 ◽

Cited By ~ 2

Author(s):

Cees J.L. Willems ◽

Andrea Vondrak ◽

Dirk K. Munsterman ◽

Marinus E. Donselaar ◽

Harmen F. Mijnlieff

Keyword(s):

Lower Cretaceous ◽

The West ◽

Geothermal Heat ◽

Palynological Analysis ◽

Thickness Prediction ◽

Lateral Extent ◽

Thickness Variations ◽

Sedimentary Aquifer ◽

Geothermal Aquifer ◽

Regional Aquifer

AbstractThe primary challenge for efficient geothermal doublet design and deployment is the adequate prediction of the size, shape, lateral extent and thickness (or aquifer architecture) of aquifers. In the West Netherlands Basin, fluvial Lower Cretaceous sandstone-rich successions form the main aquifers for geothermal heat exploitation. Large variations in the thickness of these successions are recognised in currently active doublet systems that cannot be explained. This creates an uncertainty in aquifer thickness prediction, which increases the uncertainty in doublet lifetime prediction as it has an impact on net aquifer volume. The goal of this study was to improve our understanding of the thickness variations and regional aquifer architecture of the Nieuwerkerk Formation geothermal aquifers. For this purpose, new palynological data were evaluated to correlate aquifers in currently active doublet systems based on their chronostratigraphic position and regional Maximum Flooding Surfaces. Based on the palynological cuttings analysis, the fluvial interval of the Nieuwerkerk Formation was subdivided into two successions: a Late Ryazanian to Early Valanginian succession and a Valanginian succession. Within these successions trends were identified in sandstone content. In combination with seismic interpretation, maps were constructed that predict aquifer thickness and their lateral extent in the basin. The study emphasises the value of palynological analyses to reduce the uncertainty of fluvial hot sedimentary aquifer exploitation.

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Effects of Vibration on the Preparation of Ultrathin Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007223x ◽

1973 ◽

Vol 31 ◽

pp. 358-359

Author(s):

Joseph M. Blum ◽

Edward P. Gargiulo ◽

J. R. Sawers

Keyword(s):

Cutting Speed ◽

Ground Level ◽

Environmental Vibration ◽

Block Face ◽

Ultrathin Sections ◽

Embedding Medium ◽

Thickness Variations ◽

Building Walls ◽

Cutting Direction ◽

Diamond Knife

It is now well-known that chatter (Figure 1) is caused by vibration between the microtome arm and the diamond knife. It is usually observed as a cyclical variation in “optical” density of an electron micrograph due to sample thickness variations perpendicular to the cutting direction. This vibration might be induced by using too large a block face, too large a clearance angle, excessive cutting speed, non-uniform embedding medium or microtome vibration. Another prominent cause is environmental vibration caused by inadequate building construction. Microtomes should be installed on firm, solid floors. The best floors are thick, ground-level concrete pads poured over a sand bed and isolated from the building walls. Even when these precautions are followed, we recommend an additional isolation pad placed on the top of a sturdy table.

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A high-performance oil-free backing pump for electron microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107691 ◽

1978 ◽

Vol 36 (1) ◽

pp. 110-111

Author(s):

G.K.W. Balkau ◽

E. Bez ◽

J.L. Farrant

Keyword(s):

Molecular Weight ◽

Electron Microscope ◽

Hot Spots ◽

High Performance ◽

Carbonaceous Material ◽

Contamination Rate ◽

Low Molecular Weight ◽

Principal Source ◽

Rotary Pumps ◽

Electron Microscopes

The earliest account of the contamination of electron microscope specimens by the deposition of carbonaceous material during electron irradiation was published in 1947 by Watson who was then working in Canada. It was soon established that this carbonaceous material is formed from organic vapours, and it is now recognized that the principal source is the oil-sealed rotary pumps which provide the backing vacuum. It has been shown that the organic vapours consist of low molecular weight fragments of oil molecules which have been degraded at hot spots produced by friction between the vanes and the surfaces on which they slide. As satisfactory oil-free pumps are unavailable, it is standard electron microscope practice to reduce the partial pressure of organic vapours in the microscope in the vicinity of the specimen by using liquid-nitrogen cooled anti-contamination devices. Traps of this type are sufficient to reduce the contamination rate to about 0.1 Å per min, which is tolerable for many investigations.

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Various technic for the measurement of step thickness on crystal surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109331 ◽

1978 ◽

Vol 36 (1) ◽

pp. 438-439

Author(s):

C. Boulesteix ◽

C. Colliex ◽

C. Mory ◽

B. Pardo ◽

D. Renard

Keyword(s):

Critical Thickness ◽

Symmetric Case ◽

Transmitted Intensity ◽

Crystal Surfaces ◽

Bright Field ◽

Excited Wave ◽

Highly Sensitive ◽

Contrast Mechanisms ◽

Step Thickness ◽

Thickness Variations

Contrast mechanisms, which are responsible of the various types of image formation, are generally thickness dependant. In the following, two imaging modes in the 100 kV CTEM are described : they are highly sensitive to thickness variations and can be used for quantitative estimations of step heights.Detailed calculations (1) of the bright-field intensity have been carried out in the 3 (or 2N+l)-beam symmetric case. They show that in given conditions, the two important symmetric Bloch waves interfere most strongly at a critical thickness for which they have equal emergent amplitudes (the more excited wave at the entrance surface is also the more absorbed). The transmitted intensity I for a Nd2O3 specimen has been calculated as a function of thickness t. The capacity of the method to detect a step and measure its height can be more clearly deduced from a plot of dl/Idt as shown in fig. 1.

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