Hydrocarbon identification using the AVO response correction method based on high-resolution complex spectral decomposition

Amplitude-variation-with-offset (AVO) technique is one of the primary quantitative hydrocarbon discrimination methods with prestack seismic data. However, the prestack seismic data are usually have low data quality, such as nonflat gathers and nonpreserved amplitude due to absorption, attenuation, and/or many other reasons, which usually lead to a wrong AVO response. The Neogene formations in the Huanghekou area of the Bohai Bay Basin are unconsolidated clastics with a high average porosity, and we find that the attenuation on seismic signal is very strong, which causes an inconsistency of AVO responses between seismic gathers and its corresponding synthetics. Our research results indicate that the synthetic AVO response can match the field seismic gathers in the low-frequency end, but not in the high-frequency components. Thus, we have developed an AVO response correction method based on high-resolution complex spectral decomposition and low-frequency constraint. This method can help to achieve a correct high-resolution AVO response. Its application in Bohai oil fields reveals that it is an efficient way to identify hydrocarbons in rocks, which provides an important technique for support in oil and gas exploration and production in this area.

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The Application of Seismic Data Processing Technology in Kongdian Area

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.663.876 ◽

2013 ◽

Vol 663 ◽

pp. 876-881

Author(s):

Qiang Lan ◽

Qian Zhang

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Low Frequency ◽

Processing Technology ◽

Bohai Bay ◽

Well Control ◽

Oil And Gas Exploration ◽

Time Migration ◽

Energy Compensation ◽

Static Corrections

Kongdian is located in the eastern part of Bohai Bay. This region has good prospects for oil and gas exploration, but the seismic geologic condition is very complex. After several stages of exploration, a number of significant exploration results have been achieved, but the gradually exposed problems restricted the exploration to go further. In a new round of exploration, the high and low frequency energy compensation technology, advantaged band deconvolution processing technology, dividing frequency high-precision residual static corrections, high-resolution well control-target wavelet deconvolution technology, common scattering point imaging technology and prestack time migration processing technology have been used to improve exploration accuracy. Five potential areas were found in this region according to the new processed seismic data and subsequent interpretation work, achieving the pleasant situation of initial success following the exploration in that year.

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A time-lapse seismic repeatability test using the P-Cable high-resolution 3D marine acquisition system

The Leading Edge ◽

10.1190/tle39070480.1 ◽

2020 ◽

Vol 39 (7) ◽

pp. 480-487

Author(s):

Patrick Smith ◽

Brandon Mattox

Keyword(s):

High Resolution ◽

Seismic Data ◽

Low Cost ◽

Low Frequency ◽

Time Lapse ◽

Seismic Signal ◽

Residual Energy ◽

Acquisition System ◽

Positioning Errors ◽

Seismic Surveying

The P-Cable high-resolution 3D marine acquisition system tows many short, closely separated streamers behind a small source. It can provide 3D seismic data of very high temporal and spatial resolution. Since the system is containerized and has small dimensions, it can be deployed at short notice and relatively low cost, making it attractive for time-lapse seismic reservoir monitoring. During acquisition of a 3D high-resolution survey in the Gulf of Mexico in 2014, a pair of sail lines were repeated to form a time-lapse seismic test. We processed these in 2019 to evaluate their geometric and seismic repeatability. Geometric repetition accuracy was excellent, with source repositioning errors below 10 m and bin-based receiver positioning errors below 6.25 m. Seismic data comparisons showed normalized root-mean-square difference values below 10% between 40 and 150 Hz. Refinements to the acquisition system since 2014 are expected to further improve repeatability of the low-frequency components. Residual energy on 4D difference seismic data was low, and timing stability was good. We conclude that the acquisition system is well suited to time-lapse seismic surveying in areas where the reservoir and time-lapse seismic signal can be adequately imaged by small-source, short-offset, low-fold data.

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Analytical Approaches for High-Resolution Environmental Investigations of Unconventional Oil and Gas Exploration

Advances in Chemical Pollution, Environmental Management and Protection - Environmental Issues Concerning Hydraulic Fracturing ◽

10.1016/bs.apmp.2017.08.011 ◽

2017 ◽

pp. 193-226 ◽

Cited By ~ 1

Author(s):

Doug D. Carlton ◽

Zacariah L. Hildenbrand ◽

Kevin A. Schug

Keyword(s):

High Resolution ◽

Oil And Gas ◽

Oil And Gas Exploration ◽

Unconventional Oil ◽

Unconventional Oil And Gas ◽

Analytical Approaches

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About this title - Seismic Characterization of Carbonate Platforms and Reservoirs

Geological Society London Special Publications ◽

10.1144/sp509 ◽

2021 ◽

Vol 509 (1) ◽

pp. NP-NP

Author(s):

J. Hendry ◽

P. Burgess ◽

D. Hunt ◽

X. Janson ◽

V. Zampetti

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Carbonate Platform ◽

Carbonate Platforms ◽

Oil And Gas Exploration ◽

Seismic Modelling ◽

Flow Units ◽

Development Data ◽

Seismic Characterization

Modern seismic data have become an essential toolkit for studying carbonate platforms and reservoirs in impressive detail. Whilst driven primarily by oil and gas exploration and development, data sharing and collaboration are delivering fundamental geological knowledge on carbonate systems, revealing platform geomorphologies and how their evolution on millennial time scales, as well as kilometric length scales, was forced by long-term eustatic, oceanographic or tectonic factors. Quantitative interrogation of modern seismic attributes in carbonate reservoirs permits flow units and barriers arising from depositional and diagenetic processes to be imaged and extrapolated between wells.This volume reviews the variety of carbonate platform and reservoir characteristics that can be interpreted from modern seismic data, illustrating the benefits of creative interaction between geophysical and carbonate geological experts at all stages of a seismic campaign. Papers cover carbonate exploration, including the uniquely challenging South Atlantic pre-salt reservoirs, seismic modelling of carbonates, and seismic indicators of fluid flow and diagenesis.

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High-resolution seismic processing technique with broadband,wide-azimuth, and high-density seismic data - A case study of thin-sand reservoir in eastern China

Interpretation ◽

10.1190/int-2020-0107.1 ◽

2021 ◽

pp. 1-45

Author(s):

Qin Su ◽

Huahui Zeng ◽

Yancan Tian ◽

HaiLiang Li ◽

Lei Lyu ◽

...

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Single Point ◽

Eastern China ◽

High Density ◽

Songliao Basin ◽

Seismic Processing ◽

Oil And Gas Exploration ◽

Sand Body

Seismic processing and interpretation techniques provide important tools for the oil and gas exploration of the Songliao Basin in eastern China, which is dominated by terrestrial facies. In the Songliao Basin, a large number of thin-sand reservoirs are widely distributed, which are the primary targets of potential oil and gas exploration and exploitation. An important job of the exploration in the Songliao Basin is to accurately describe the distribution of these thin-sand belts and the sand-body shapes. However, the thickness of these thin-sand reservoirs are generally below the resolution of the conventional seismic processing. Most of the reservoirs are thin-interbeds of sand and mudstones with strong vertical and lateral variations. This makes it difficult to accurately predict the vertical and horizontal distribution of the thin-sand bodies using the conventional seismic processing and interpretation methods. Additionally, these lithologic traps are difficult to identify due to the complex controlling factor and distribution characteristics, and strong concealment. These challenges motivate us to improve the seismic data quality to help delineate the thin-sand reservoirs. In this paper, we use the broadband, wide-azimuth, and high-density integrated seismic exploration technique to help delineate the thin-reservoirs. We first use field single-point excitation and single-point receiver acquisition to obtain seismic data with wide frequency-bands, wide-azimuth angles, and high folds, which contain rich geological information. Next, we perform the near-surface Q-compensation, viscoelastic prestack time migration, seismic attributes, and seismic waveform indication inversion on the new acquired seismic data. The 3D case study indicates the benefits of improving the imaging of thin-sand body and the accuracy of inversion and reservoir characterization using the method in this paper.

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Prediction of Favorable Carbonate Reservoirs under Extremely Thick Salts via Poststack Facies-Controlled and Prestack Zoeppritz Equation Inversions in the Santos Basin of Brazil

Geofluids ◽

10.1155/2020/6205185 ◽

2020 ◽

Vol 2020 ◽

pp. 1-20

Author(s):

Sheng Zhang ◽

Suoliang Chang ◽

Handong Huang ◽

Yinping Dong ◽

Youyi Shen ◽

...

Keyword(s):

Oil And Gas ◽

Large Angle ◽

Low Frequency ◽

Prediction Method ◽

Approximate Equation ◽

Carbonate Reservoirs ◽

Linear Inversion ◽

Pass Filter ◽

Low Pass Filter ◽

Oil And Gas Exploration

Subsalt carbonate rocks in Brazil’s deepwater region have broad prospects for oil and gas exploration and development. Due to the low-frequency bandwidth of the seismic data and the poor signal quality for this kind of reservoir target, there is a demand for accurate seismic prediction methods. We employ the facies-controlled inversion using a low-pass filter matrix to ensure the accuracy of the low frequency and to improve the robustness of the inversion results. We integrated the concept of adaptive regularization constraint of the Zoeppritz equation into the generalized linear inversion theory framework, which overcomes the shortcomings of the approximate equation. Making full use of the large angle prestack seismic information, Zoeppritz equation inversion improves the accuracy of the inversion results. The application of this method in carbonate reservoirs under extremely thick salts in the Santos Basin of Brazil indicates the feasibility and practicality of the proposed integrated prediction method.

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The Local Structure Research on the Nanpu 5th Construct

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.733.80 ◽

2015 ◽

Vol 733 ◽

pp. 80-83

Author(s):

Chun Qiu ◽

Ming Xue Zhang ◽

Xiao Yan Lv

Keyword(s):

Seismic Data ◽

Local Structure ◽

Oil And Gas ◽

Structural Characteristics ◽

Bohai Bay ◽

Hydrocarbon Accumulation ◽

Local Structures ◽

Huanghua Depression ◽

Exploration Area ◽

Structure Research

The Nanpu 5th construct is in the western part of Huanghua Depression Nanpu Sag of Bohai Bay Basin, was a complicated anticline belt that develops between Jian Dong fault and the downthrown side of the southwestern Zhuang fault and the favorable exploration area is 120km2. On the basis of the region's large number of multi-channel seismic data analysis and interpretation, the trap types, structural characteristics and distribution of local structures between the layers of the region are researched. Interlayer local structures in the area are mainly divided into nose structure and small anticline. The fault zone is a structural high in the region, to promote oil and gas to migrate and accumulate to the low-potential zones that become favorable zones for hydrocarbon accumulation, but the real decisive construct parts of the hydrocarbon accumulation is positive local structure in favorable zones which point out the region for hydrocarbon accumulation.

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Automatic, geologic layer-constrained well-seismic tie through blocked dynamic warping

Interpretation ◽

10.1190/int-2016-0160.1 ◽

2017 ◽

Vol 5 (3) ◽

pp. SJ81-SJ90 ◽

Cited By ~ 1

Author(s):

Kainan Wang ◽

Jesse Lomask ◽

Felix Segovia

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Synthetic Data ◽

Optimal Solution ◽

Velocity Model ◽

Data Set ◽

Oil And Gas Exploration ◽

Interval Velocity ◽

Velocity Changes ◽

Dynamic Warping

Well-log-to-seismic tying is a key step in many interpretation workflows for oil and gas exploration. Synthetic seismic traces from the wells are often manually tied to seismic data; this process can be very time consuming and, in some cases, inaccurate. Automatic methods, such as dynamic time warping (DTW), can match synthetic traces to seismic data. Although these methods are extremely fast, they tend to create interval velocities that are not geologically realistic. We have described the modification of DTW to create a blocked dynamic warping (BDW) method. BDW generates an automatic, optimal well tie that honors geologically consistent velocity constraints. Consequently, it results in updated velocities that are more realistic than other methods. BDW constrains the updated velocity to be constant or linearly variable inside each geologic layer. With an optimal correlation between synthetic seismograms and surface seismic data, this algorithm returns an automatically updated time-depth curve and an updated interval velocity model that still retains the original geologic velocity boundaries. In other words, the algorithm finds the optimal solution for tying the synthetic to the seismic data while restricting the interval velocity changes to coincide with the initial input blocking. We have determined the application of the BDW technique on a synthetic data example and field data set.

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