Stratigraphic correlation techniques
Stratigraphic correlation techniques. When information derived from two outcrops is integrated, the time interval they represent is probably greater than that of each alone. Figure 7. 3). 5 and 6 in Albian through Santonian strata in five wells, offshore mid-Norway. Graphic correlation continues to develop and spread as more geologists use this important and innovative technique. 2 summarizes these steps and provides generalized estimates of the magnitude of the uncertainty associated with each aspect of the correlation and dating of the stratigraphic record. KEY WORDS: cross correlation, mapping, plotting, statistics, stratigraphy, structure, electric logging. 7. Dec 1, 2020 · This is evident in publications by Dunay and Hailwood (1995) on non-biostratigraphical methods of dating and correlation; by Shanley and McCabe (1998) on the relative role of eustacy, climate, and tectonism on the deposition of continental rocks; and by Ratcliffe and Zaitlin (2010) on the application of a variety of modern stratigraphic techniques. Aug 26, 2021 · 3. Fig. Dec 21, 2019 · Stratigraphic correlation is the process of determining the equivalence of age or stratigraphic position of layered rocks in different areas. Deep learning, known for its robust feature extraction capabilities, has seen continuous adoption by scholars in the realm of well logging stratigraphic correlation tasks. Lithostratigraphy: The study and organization of strata on the basis of physical lithologic characteristics. Using the dynamic time warping (DTW) algorithm, automated correlation of two wells is a fairly simple task; DTW can also be used to correlate a large number of wells along a Stratigraphic correlation is an additional tool used for understanding how depositional environments change geographically. In older successions, however, the demonstration of the primary nature of oxygen isotope signals is often The correlation of strata on the basis of their stacking patterns sets sequence stratigraphy apart from other correlation methods that rely on similarities of units in terms of lithology (i. Correlation of stratigraphic sequences is an important problem. Apr 16, 2016 · Stratigraphic correlation of wells involves correlation of stratigraphic interfaces which should be continuous across the area between the wells. Multiple dynamic matching: a new approach to well log correlation. Stratigraphic correlation methods include lithostratigraphy, biostratigraphy Simulation of a geostratigraphic unit is of vital importance for the study of geoinformatics, as well as geoengineering planning and design. Stratigraphic correlation by computer of two geophysical logs involved the vertical shifting of one log relative to another until their characteristics were aligned as indicated by the maximum value of the cross correlation function. (In this paper, correlation There are four main types of correlation: stratigraphic, lithostratigraphic, chronostratigraphic, and biostratigraphic. Techniques for quantitative stratigraphic correlation: a review and annotated bibliography. It requires input from a variety of geophysical surveys ranging Schumm SA (1993) River response to base level change: implications for sequence stratigraphy. Some of the commonly used stratigraphic tools include 1. 1. Geologists construct geologic histories of areas by mapping and making stratigraphic columns-a detailed description of the strata from bottom to Aug 1, 2006 · Papers resulting from the Fourth International Symposium on the Cambrian System, held in Nanjing, China, in 2005 cover three major aspects of geology and paleontology: (1) the developing global standard for Cambrian chronostratigraphy or regional correlation schemes; (2) regional lithostratigraphy, sedimentology and paleoenvironments; (3) organismal paleobiology, phylogenetic affinities and wavelet based techniques and was proved to be superior. The methods proposed in this paper do include correlations across gaps and allow for completely May 16, 2019 · 1. Part of this work was performed under the auspices of the International Geological Correlation Program (IGCP Project 148: Evaluation and Development of Quantitative Stratigraphic Correlation Techniques, 1976-1985) and the International Commission on Stratigraphy (Committee for Quantitative Stratigraphy, from 1985 onward). Stratigraphic correlation is the process of establishing which sedimentary strata are the same age at distant geographical areas by means of their stratigraphic relationship. general applications include regional stratigraphic correlation, identification and prediction of reservoir, cap and source rocks and their time–space distribution. A major problem is its inability to include correlations across gaps caused by local nondeposition or eroded strata. Stratigraphic boundaries generally separate rocks belonging to significantly different environment or lithology (Fig. Some of these errors may be cumulative, as discussed Align is introduced, a user-friendly computer app that makes accessible a published dynamic time warping (DTW) algorithm that catalogs a library of alignments between two time-series data sets by systematically exploring assumptions about the temporal overlap and relative sedimentation rates between the two stratigraphic sections. , 2012). Geologists now have access to various tools and methods that aid in the accurate analysis and interpretation of rock strata. In addition, they are extended to include correlation of a fragmentary sequence with a longer complete sequence and to include correlations of more than two sequences. The stratigraphic correlation results of multiple wells computed using SegNet and the stratigraphic correlation results of ground truth. , sedimentary plane, foliation, and cleavage plane). ( a ) High resolution airborne EM 150 kHz depth slice, with locations of test pits and cross-sections. Presumably if all the world’s outcrops were integrated, sediments representing all of Great efforts are made in stratigraphy to reconstruct and interpret ancient environmental conditions through stratigraphic correlation. Well logs show blocky sands with lateral variations. typed as structural, stratigraphic and seismic stratigraphy. Babcockb, Shan-Chi Feb 9, 2016 · The spatial correlation in the local neighborhood system is decomposed into two components named normal and tangential correlation regarding to plane orientation of geological formation (e. Seismic stratigraphy is typically a regional geologic interpretation of seismic 2D data, and is described with schematics and real seismic image illustrations. lithostratigraphy), fossil assemblages (i. biostratigraphy), magnetic characteristics (i. Integration of chemostratigraphy with machine learning techniques has Aug 1, 2006 · Papers resulting from the Fourth International Symposium on the Cambrian System, held in Nanjing, China, in 2005 cover three major aspects of geology and paleontology: (1) the developing global standard for Cambrian chronostratigraphy or regional correlation schemes; (2) regional lithostratigraphy, sedimentology and paleoenvironments; (3) organismal paleobiology, phylogenetic affinities and Techniques of Stratigraphic Correlation. The measured total stratigraphic ranges of 44 palynomorphs present in five wells from the Niger Delta Basin have been assembled by graphic correlation method into a chronostratigraphic framework. Stratigraphic correlation is an additional tool used for understanding how depositional environments change geographically. Stratigraphic correlation utilizes various techniques to align layers of rock and sediment. This process is experimental and the keywords may be updated as the learning algorithm improves. Keywords Well logging Stratigraphic correlation Stratigraphic interfaces Wavelet transform Multi- similarity. Rock Unit Classification. It is valid for theoretically complete stratigraphie sequences, but not for stratigraphie sequences as they commonly occur. To make these techniques more readily accessible and to encourage their use, this paper presents a brief, general review of the problem of quantitative stratigraphic correlation and then shows how, using a natural framework for stratigraphic correlation, the stratigraphic time-series, there can be seen an orderly pattern among them. Jan 1, 2018 · When combined with airborne EM and other geophysical techniques, sequence stratigraphy is an effective exploration tool used to identify and delineate buried aggregate sources in drift deposits. Based on firm foundations, capable of evolving through the developments of new techniques, the rise of new concepts and their integration with other stratigraphic means it is the most dependable means of stratigraphic correlation and dating available to the stratigrapher. Reservoir quality is strongly associated with transgressive-regressive cycles and trends, and its significant time-stratigraphic bounding surfaces generally coincide with critical petrophysical boundaries that compartmentalize subsurface fluid flow. Modern technology and advanced analytical techniques have greatly improved the interpretation of stratigraphic data. The time span of a chronozone is the time span of a previously designated stratigraphic unit or interval, such as a lithostratigraphic, biostratigraphic, or magnetostratigraphic polarity unit. 1 Current Status and Prospect of Sequence Stratigraphy Study. 2001) and advances in sediment core-scanning have led to an increase in stratigraphical subdivision using techniques allied to lithostratigraphy, such as geochemistry and tephrochronology. It is valid for theoretically complete stratigraphic sequences, but not for stratigraphic sequences as they commonly occur. Rock type, color, mineral composition, grain size, overall texture. Jun 16, 2023 · Stratigraphic correlation of geophysical well logs is one of the most important—and most time-consuming—tasks that applied geoscientists perform on a daily basis. Jul 1, 1980 · Cross-association is a standard correlation technique. 12 and Fig. 1 Stratigraphic Correlation. The correlation of terrestrial sediment sequences relies on robust stratigraphical frameworks and the organization of terrestrial sediments and landforms into distinctive, useful, mappable units based on their properties or attributes (Salvador 1994, p. Advances in the analytical technology and integration of data from field Jan 1, 2015 · Biostratigraphy is the only non-iterative method of relative dating. In addition, seismic amplitude or phase information is not Nov 1, 2023 · Introduction. Article Google Scholar Aug 1, 2019 · The stratigraphic correlation of well logs plays an essential role in characterizing subsurface reservoirs. Aug 27, 2022 · Correlation of events in the optimum sequence and zonation of Figs. PRINCIPLES OF CORRELATION In simplest sense stratigraphic correlation is the demonstration of equivalency of stratigraphic units. Jan 1, 2014 · The calibration to linear time of the succession of events recorded in the rocks of the Earth has three components: (1) the international stratigraphic divisions and their correlation in the global rock record; (2) methods of measuring linear time or elapsed durations from the rock record; and (3) methods of joining the stratigraphic scale and Jan 1, 1995 · Stratigraphic correlation involves three distinct tasks: establishing the temporal sequence of marker events (sequencing task), determining the relative sizes of the intervals between those events (spacing task), and locating the horizons that correspond in age with each event in every section (locating task). 2 (a) illustrates a standard geometric condition of element i and one of its neighbor elements j. 13 ). . Stratigraphic correlation underpins all understanding of Earth Dec 1, 2023 · The solid and dashed lines indicate the ground truth and predicted stratigraphic correlation results, respectively. Stratigraphic correlation of wells comes at an advanced stage of reservoir estimation, where accurate quantitative information is required for prospect evaluation of the target reserve. 4). e. A machine learning-based method is proposed to extract geotechnical features for stratigraphic correlation (Nonogaki and Nemoto, 2021). In this work, we propose the Attention Based Dense Network (ASDNet) for the stratigraphic correlation of well logs. To solve this problem, this study proposes a machine learning method for Jan 1, 1995 · This collection of papers presents a summary of the technique as currently practiced and it should provide a starting point for those interested in high resolution stratigraphy through graphic correlation. 11. It is a set of scientific activities that seek to match rock patterns across distances. Carbon isotope stratigraphy is a very powerful tool that works on timescales of < 10 kyr, and therefore, can be used to correlate and constrain sedimentary sequences on Milankovitch timescales. Jun 13, 2024 · Stratigraphic Correlation. Gaps in correlation (unconformities) caused by local nondeposition or eroded strata can include in a single “event” several strata Whether the geologist is dealing with roadside outcrops, subsurface data from a petroleum play, or regional seismic lines, one of the first problems to be encountered is that of stratigraphic correlation. Modular in design and concept, the system employs a mean-value, moving-window algorithm for zoning digitized well logs, a stretching algorithm, a cross-correlation program, and a mapping function that highlights correlations between zones. This manual stratigraphic correlation of numerous wells in mature fields can be time Cross-association is a standard correlation technique. The match game: New stratigraphic correlation algorithms. Further work will focus on improving correlation results when major unconformities or onlap surfaces are present. Apr 11, 2024 · Stratigraphic correlation is about making connections. However, it suffers from a small amount of training data and expensive computing time. 2. ABSTRACT Most seismic horizon extraction methods are based on seismic local reflection slopes that locally follow seismic structural features. Abstract The development of techniques for quantitative stratigraphic correlation has tended to outstrip their acceptance by practising Cross-association is a standard correlation technique. ing correlation between sets of data is described, and idealized models are shown. Feb 18, 2023 · Create stratigraphic columns and correlations using multiple techniques 5. Correlation can be determined by using magnetic polarity reversals , rock types, unique rock sequences, or index fossils. e Workshop on Quantitative Stratigraphic Correlation Techniques: Ottawa, February 1980. A brief, general review of the problem of quantitative stratigraphic correlation is presented and it is shown how, using a natural framework for stratgraphic correlation, the stratig graphic time-series, there can be seen an orderly pattern among them. The algorithm does not interpolate data and it is as computationally efficient as the standard Jun 25, 2021 · Techniques of seismic calibration, horizon correlation, preparing seismic maps, and velocity modelling and depth conversion are elaborated with examples and illustrations. 12. its calculation techniques have not been explained Feb 1, 2015 · This method helps stratigraphic correlation with ease where other formal stratigraphic methods have limitations or fail to achieve required spatiotemporal resolution. J Geology 88: 451–457. Short Notes; Published: February 1981; Volume 13, pages 81–91, (1981) The study of strata is called stratigraphy, and using a few basic principles, it is possible to work out the relative ages of rocks. Seismic shooting and processing is now a highly sophisticated process, and its practitioners like to talk about seismic stratigraphy as if it can provide virtually all the answers, not only about structure, but about the stratigraphic subdivision of a basin, regional correlation, and even lithofacies. Geologists construct geologic histories of areas by mapping and making stratigraphic columns-a detailed description of the strata from bottom to Stratigraphic correlation involves establishing relationships between rock layers in different locations based on principles like the law of superposition and fossil succession. , Friedrich et al. Although correlation of strata over modest distances often can be accomplished by tracing particular beds from place to place, correlation over long distances and over the oceans almost invariably involves comparison of Stratigraphic Correlation; Seismic Stratigraphy; These keywords were added by machine and not by the authors. A quantified approach to the lithostratigraphic correlation of site investigation borehole logs. Application of A brief, general review of the problem of quantitative stratigraphic correlation is presented and it is shown how, using a natural framework for stratgraphic correlation, the stratig graphic time-series, there can be seen an orderly pattern among them. The methods proposed in this paper do include correlations across gaps and allow for completely Study with Quizlet and memorize flashcards containing terms like The study of fossils is called:, The English surveyor who developed the technique of stratigraphic correlation between regions was:, The study of what happens to an organism's remains after death is: and more. It should be recognized, however, that while the stratigraphic unit on which the chronozone is based extends geographically only as far as its diagnostic Hart presents a historical summary of seismic stratigraphy and suggests some potential avenues for future collaborative research. Article Google Scholar Smith TF, Waterman MS (1980) New stratigraphic correlation techniques. Mar 1, 1999 · Ramkumar (1999) discussed the importance of chemostratigraphy in petroleum exploration and stratigraphic correlation. Various types of stratigraphic surfaces are enumerated as follows: Sign in to download full-size image. Stratigraphy comprises two basic elements, sequence subdivision and correlation. The well correlation was also independently verified by identifyingmarker beds using seismic data in between the wells, and there was good agreement between the results that were obtained. Nonetheless, current deep learning algorithms often struggle to accurately capture A brief, general review of the problem of quantitative stratigraphic correlation is presented and it is shown how, using a natural framework for stratgraphic correlation, the stratig graphic time-series, there can be seen an orderly pattern among them. 1 Introduction Stratigraphy is the area of geology that deals with sedimentary rocks and layers and how they relate to geologic time; it is a significant part of historical geology. Jul 1, 2017 · The graphic correlation method provides better and higher resolution to the stratigraphic problems than zonation biostratigraphy. Sep 20, 2023 · 4. Other articles where stratigraphic correlation is discussed: geology: Paleontology: …and on different continents, involves stratigraphic correlation from place to place. Some of these errors may be cumulative, as discussed Six main “steps” are involved in the dating and correlation of stratigraphic events (Miall 1994). Jan 1, 1975 · The recognition of an identical stratigraphic unit in two geographically different locations is known as “stratigraphical correlation” and as correlation is one of the basic operations in stratigraphical analysis. Use stratigraphic tools and techniques. Sequence Stratigraphy: Analyzes sedimentary sequences influenced by sea-level changes and tectonic shifts for deeper comprehension of Earth's dynamics. 4. It allows geologists to correlate rock layers globally to better understand Earth's geological history and environmental changes over time. In order to reconstruct depositional environments and Dec 29, 2015 · Six main “steps” are involved in the dating and correlation of stratigraphic events (Miall 1994). Green and red colored correlation lines are from events that have below average stratigraphic standard deviation, and are best track the same stratigraphic levels. Through deep learning techniques such as transfer learning, the proposed methodology can be readily applied to other fields even with limited training data. INTRODUCTION Correlation of subsurface data is the first step taken by the geologist to Advances in Cambrian stratigraphy and paleontology: Integrating correlation techniques, paleobiology, taphonomy and paleoenvironmental reconstruction Mao-Yan Zhua,∗, Loren E. Sequence stratigraphy has been widely applied in marine facies and continental facies prospective areas and mature oil–gas exploration regions, particularly There are four main types of correlation: stratigraphic, lithostratigraphic, chronostratigraphic, and biostratigraphic. Correlation of logs with different thicknesses of strata was more complicated and involved a two-step process: (1) resampling the log at an expanded or stretched Biostratigraphy, chemostratigraphy, and sequence stratigraphy. δ 18 O is usually measured on benthic foraminifera, to avoid isotopic gradient effects. Figure 1: Individual rock layers, or strata, can be seen Jan 1, 2023 · A convolutional and recurrent neural networks is proposed to create well top and zonation interpretations for automated stratigraphic correlation (Tokpanov and Smith, 2020). Stratigraphic Correlation: Techniques linking rock layers across locations using fossils, composition, and absolute dating methods like radiometric dating. Cross-dating of sites, comparing geologic strata at one site with another location and extrapolating the relative ages in that manner, is still an important dating strategy used today, primarily when sites are far too old for absolute dates to have much Jan 1, 2024 · Applying the sequence stratigraphic technique to reservoir basin analysis is a crucial step in converting the lithology data from well-log data into genetic packages, which are useful to assess subtle stratigraphic reservoirs. The basis of these New algorithms for automatic correlation of geologic strata are introduced. A simplistic lithostratigraphic correlation that may result if only log data were available (top) and the chronstratigraphically-grounded correlation once stratigraphic techniques (in this case palaeomagnetism and d13C) are applied (bottom) provide time lines and a sequence stratigraphic approach can be taken. These methods help piece together a timeline of Earth's geological history, allowing for a better understanding of past climates, life forms, and environmental changes. g. But in broader sense correlation means establishing equivalency in terms lithology, paleontology and chronology Though it may seem extremely difficult, yet it is possible in many cases to correlate rocks formed at different places during the same geological time Nov 26, 2020 · In the vertical section, terrestrial stratigraphical correlation is also commonly facilitated by biostratigraphy (Tzedakis et al. In order to reconstruct depositional environments and Aug 1, 2006 · Advances in Cambrian stratigraphy and paleontology: Integrating correlation techniques, paleobiology, taphonomy and paleoenvironmental reconstruction August 2006 Palaeoworld 15(3):217-222 Abstract Stratigraphic correlation of well logs is based on interactive interpreter-based pattern recognition. This paper describes an algorithm for the semiautomatic shifting and stretching of one well log relative to another until a local maximum correlation coefficient between the two logs is found. Machine learning methods achieve Jan 1, 2020 · In this manner, carbon isotope stratigraphy can be developed from many organic and inorganic proxies in geologic time. Geologic time is vast, providing plenty of time for the evolution of various lifeforms, and some of these have become preserved as fossils that can be used for biostratigraphic correlation. Gaps in correlation (unconformities) caused by local nondeposition or eroded strata can include in a single “event” several strata New algorithms for automatic correlation of geologic strata are introduced. Figure 5. These algorithms were developed by molecular biologists for coping with the irregular patterns of amino-acids in human Jun 16, 2023 · The main advantage of this approach over conventional manual log correlation workflows—or automated techniques that focus on one top at a time—is that it quickly provides an overview of the large-scale stratigraphic structure, while also generating a large number of stratigraphic tops if high-resolution detail is of interest. Geologists Jan 21, 2021 · Stratigraphy: Assuming that soil layers in a deposit accumulate on top of one another, and that the bottom layers will be older than the top layers, stratigraphy allows archaeologists to construct a relative chronological sequence from the oldest (bottom) to youngest (top) layers. It is critical to understanding earth history because Aug 1, 2019 · The correlation was visually completed based on INDTEL from two wells (Fig. Compared with CYCLOLOG, the results of the new method of correlation represent a higher resolution because in the new method nine correlation lines were selected based on negative and positive turning points of the INDTEL compared to the six correlation lines in the CYCLOLOG method. Techniques of Stratigraphic Correlation. Cross-association is a standard correlation technique. It offers a method for the correlation of lithostratigraphy in wells (Omigie and Alaminiokuma, 2020). Feb 27, 2015 · Chemostratigraphy, the analysis of geochemical signatures in a stratigraphic context , has gained significance in geosciences. Artifacts found in these layers are at least as old as the Whether the geologist is dealing with roadside outcrops, subsurface data from a petroleum play, or regional seismic lines, one of the first problems to be encountered is that of stratigraphic correlation. May 4, 2024 · Well logging curves serve as indicators of strata attribute changes and are frequently utilized for stratigraphic analysis and comparison. Stratigraphic correlation is a tool for identifying strata units and subsequent flow units. INTRODUCTION TO STRATIGRAPHIC ANALYSIS AND LITHOLOGIC CORRELATION. The methods proposed in this paper do include correlations across gaps and allow for completely Stratigraphic correlation using well-log data for the targeted distal-fluvial reservoir. The study of geochemical Oct 2, 2020 · In other words, artifacts found in the upper layers of a site will have been deposited more recently than those found in the lower layers. A skilled interpreter identifies similar patterns (such as upward fining and coarsening) in user-defined well sections and links them using either a conscious or subconscious stratigraphic model. The algorithms are extensions of the Smith and Waterman (1980) dynamic programming technique and include several features that greatly increase the utility for sedimentary sequences. Download: Download high-res image (1MB) Download: Download full-size image; Fig. Aug 17, 2021 · Stratigraphic Correlation. Workflows for the 2D interpre-tation types are described in this chapter, underscoring the basic principles along with some of the application shortcomings that crop up during normal interpretation practices. Stratigraphers use correlation for most practical applications; there is indeed a great monetary benefit from understanding where fossil fuels and other raw materials can be located based on the lithology of Oct 19, 2020 · The resulting stratigraphic correlation proves to be extremely reliable even with a small number of seed wells, and it requires minimal user intervention during the process. A traditional method depends on the guidance of expert experience, which is subjective and limited, thereby making the effective evaluation of a stratum simulation quite impossible. The methods proposed in this paper do include correlations across gaps and allow for completely Jan 1, 1979 · A system for automated correlation of digitized well logs based on lithostratigraphic characters has been developed. 5. There are four main types of correlation: stratigraphic, lithostratigraphic, chronostratigraphic, and biostratigraphic. 137). Sequence stratigraphy theory is evolved from seismic stratigraphy; the theory was early applied in sedimentary strata of passive continental marginal marine facies (with simple structures), and then, it was applied in different basins to investigate and explore the distribution regularity of different sedimentary filling systems. Seismic stratigraphy, as practiced by geologic interpreters, is a mature science that uses principles of stratigraphy (largely based on reflection geometries) to interpret seismic data. I. Performing high-resolution sequence stratigraphy analysis is a crucial step in reservoir characterization workflow. There are a wide variety of ways that stratigraphic patterns are identified and matched, and quite commonly, the patterns do not match up perfectly. Jan 1, 2016 · To establish stratigraphic schemes at archaeological sites, some archaeologists and geoarchaeologists have simply followed the rules of the Code of Stratigraphic Nomenclature established by geologists (North American Commission on Stratigraphic Nomenclature, 1983, 2005) or the International Stratigraphic Guide (Hedberg, 1976; Salvador, 1994 We have written a software package called ‘ChronoLog’ to apply this workflow to datasets with relatively simple stratigraphy; in such settings, the results tend to match or outperform manual interpretations. The algorithm grew out of a graphical interpretation of the standard shift correlation procedure. J Geology 101: 279–293. Techniques of seismic calibration, horizon correlation, preparing seismic The main advantage of this approach over conventional manual log correlation workflows—or automated techniques that focus on one top at a time—is that it quickly provides an overview of the large-scale stratigraphic structure, while also generating a large number of stratigraphic tops if high-resolution detail is of interest. However, these methods often fail to correctly track horizons across discontinuities such as faults and noise because the local slopes can only correctly follow laterally continuous reflections. Oxygen isotope chemostratigraphy forms the backbone of Meso- and Cenozoic stratigraphic correlation of marine sediments (e. When enough overlapping segments of the stratigraphic record are matched together, we can eventually reconstruct the entire stratigraphic record. Although the technique has been Dating - Correlation, Stratigraphy, Radiometric: Correlation is, as mentioned earlier, the technique of piecing together the informational content of separated outcrops. magnetostratigraphy), geochemical signatures (i. Using these techniques, most problems can be handled by hand calculation. Each of these techniques allows for the matching of strata, or correlation, from one locality to another (Figure 3. In 1980, Smith and Waterman published an example of the application of gene-typing algorithms to the problem of matching stratigraphic sequences. eemrcl eeipuz hxq ouiy zwwfqqn vdmykj dkfjwyf trb hbnfzqjcf zyf