Patent Publication Number: US-2022229199-A1

Title: Interpreting seismic faults with machine learning techniques

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional patent application having Ser. No. 62/853,681, which was filed on May 28, 2019 and is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Interpretation of geological structures within seismic datasets can enable the exploration, development, and production of resources such as petroleum, among others. In some examples, interpreting the seismic datasets can include interpreting or identifying fault structures in geological formations. Due to the geological complexities in subsurface regions and limitations associated with seismic imaging resolution, interpretation of seismic datasets can be inefficient, inaccurate, and require performing a large number of repetitive tasks. For example, manually interpreting seismic data can be impractical because manually interpreting seismic data is labor intensive and time consuming, particularly with ever increasing quantities of costly seismic datasets. 
     In some examples, machine learning techniques can be used to automate fault interpretation from seismic data. The machine learning techniques can detect faults along vertical seismic sections such as inline seismic sections or crossline seismic sections. In some embodiments, labeled seismic data can be detected as user input. The labeled seismic data can train a machine learning technique, such as a deep neural network, among others. The trained machine learning technique can be used to detect faults on a given two-dimensional (2D) seismic image corresponding to inline seismic data or crossline seismic data. In some embodiments, the machine learning technique can then detect predicted faults for subsequent seismic data or 2D seismic images. In some examples, the machine learning techniques can aggregate predicted faults from the 2D seismic images to form predicted faults within a three-dimensional (3D) seismic volume. However, when using 3D seismic images versus 2D seismic images, the results include a high number of false positive noise and often lack coherence in 3D. For example, machine learning techniques can generate a high number of false positive values when the seismic data is noisy. 
     SUMMARY 
     Embodiments of the disclosure provide a method for interpreting seismic data. The method includes receiving seismic data that represents a subterranean volume, and generating one or more inline probability values and one or more crossline probability values using a first machine learning technique. The first machine learning technique is trained to identify one or more vertical fault lines in a seismic volume based on the seismic data. The method also includes generating a merged data set by combining the one or more inline probability values and the one or more crossline probability values, training a second machine learning technique based on a subset of labeled horizontal planes from the merged data set, the second machine learning technique trained to identify one or more horizontal fault lines from the seismic volume, and generating a representation of the seismic volume based on the second machine learning technique, the representation including an indication of a three-dimensional fault structure within the seismic volume. 
     Embodiments of the disclosure also provide a computing system for interpreting seismic data. The computing system includes one or more processors, and a memory system including one or more non-transitory computer-readable media storing instructions that, when executed by at least one of the one or more processors, cause the computing system to perform operations. The operations include receiving seismic data that represents a subterranean volume, and generating one or more inline probability values and one or more crossline probability values using a first machine learning technique. The first machine learning technique is trained to identify one or more vertical fault lines in a seismic volume based on the seismic data. The operations also include generating a merged data set by combining the one or more inline probability values and the one or more crossline probability values, training a second machine learning technique based on a subset of labeled horizontal planes from the merged data set, the second machine learning technique trained to identify one or more horizontal fault lines from the seismic volume, and generating a representation of the seismic volume based on the second machine learning technique, the representation including an indication of a three-dimensional fault structure within the seismic volume. 
     Embodiments of the disclosure further provide at least one non-transitory computer-readable medium for interpreting seismic data, the at least one computer-readable medium comprising a plurality of computer-executable instructions that, in response to execution by a processor, cause the processor to receive seismic data that represents a subterranean volume, and generate one or more inline probability values and one or more crossline probability values using a first machine learning technique. The first machine learning technique is trained to identify one or more vertical fault lines in a seismic volume based on the seismic data. The instructions further cause the processor to generate a merged data set by combining the one or more inline probability values and the one or more crossline probability values, train a second machine learning technique based on a subset of labeled horizontal planes from the merged data set, the second machine learning technique trained to identify one or more horizontal fault lines from the seismic volume, and generate a representation of the seismic volume based on the second machine learning technique, the representation including an indication of a three-dimensional fault structure within the seismic volume. 
     Thus, the computing systems and methods disclosed herein are more effective methods for processing collected data that may, for example, correspond to a surface and a subsurface region. These computing systems and methods increase data processing effectiveness, efficiency, and accuracy. Such methods and computing systems may complement or replace conventional methods for processing collected data. This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present teachings and together with the description, serve to explain the principles of the present teachings. In the figures: 
         FIGS. 1A, 1B, 1C, 1D, 2, 3A, and 3B  illustrate simplified, schematic views of an oilfield and its operation, according to an embodiment. 
         FIG. 4  illustrates a process flow diagram of a method for interpreting seismic data, according to an embodiment. 
         FIG. 5  illustrates a block diagram for interpreting 3D seismic data with machine learning techniques, according to an embodiment. 
         FIG. 6A  is an example of a horizontal plane of data from analyzed 3D seismic data, according to an embodiment. 
         FIG. 6B  is an example of an interpretation of fault lines within a horizontal plane of data from analyzed 3D seismic data, according to an embodiment. 
         FIG. 7  is an example diagram depicting output from a first machine learning technique, according to an embodiment. 
         FIG. 8  is an example diagram depicting output from a second machine learning technique, according to an embodiment. 
         FIG. 9  illustrates a schematic view of a computing system, according to an embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings and figures. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. 
     It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first object could be termed a second object, and, similarly, a second object could be termed a first object, without departing from the scope of the invention. The first object and the second object are both objects, respectively, but they are not to be considered the same object. 
     The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the description of the invention and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Further, as used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. 
     Attention is now directed to processing procedures, methods, techniques and workflows that are in accordance with some embodiments. Some operations in the processing procedures, methods, techniques and workflows disclosed herein may be combined and/or the order of some operations may be changed. 
       FIGS. 1A-1D  illustrate simplified, schematic views of oilfield  100  having subterranean formation  102  containing reservoir  104  therein in accordance with implementations of various technologies and techniques described herein.  FIG. 1A  illustrates a survey operation being performed by a survey tool, such as seismic truck  106 . 1 , to measure properties of the subterranean formation. The survey operation is a seismic survey operation for producing sound vibrations. In  FIG. 1A , one such sound vibration, e.g., sound vibration  112  generated by source  110 , reflects off horizons  114  in earth formation  116 . A set of sound vibrations is received by sensors, such as geophone-receivers  118 , situated on the earth&#39;s surface. The data received  120  is provided as input data to a computer  122 . 1  of a seismic truck  106 . 1 , and responsive to the input data, computer  122 . 1  generates seismic data output  124 . This seismic data output may be stored, transmitted or further processed as desired, for example, by data reduction. 
       FIG. 1B  illustrates a drilling operation being performed by drilling tools  106 . 2  suspended by rig  128  and advanced into subterranean formations  102  to form wellbore  136 . Mud pit  130  is used to draw drilling mud into the drilling tools via flow line  132  for circulating drilling mud down through the drilling tools, then up wellbore  136  and back to the surface. The drilling mud is typically filtered and returned to the mud pit. A circulating system may be used for storing, controlling, or filtering the flowing drilling mud. The drilling tools are advanced into subterranean formations  102  to reach reservoir  104 . Each well may target one or more reservoirs. The drilling tools are adapted for measuring downhole properties using logging while drilling tools. The logging while drilling tools may also be adapted for taking core sample  133  as shown. 
     Computer facilities may be positioned at various locations about the oilfield  100  (e.g., the surface unit  134 ) and/or at remote locations. Surface unit  134  may be used to communicate with the drilling tools and/or offsite operations, as well as with other surface or downhole sensors. Surface unit  134  is capable of communicating with the drilling tools to send commands to the drilling tools, and to receive data therefrom. Surface unit  134  may also collect data generated during the drilling operation and produce data output  135 , which may then be stored or transmitted. 
     Sensors (S), such as gauges, may be positioned about oilfield  100  to collect data relating to various oilfield operations as described previously. As shown, sensor (S) is positioned in one or more locations in the drilling tools and/or at rig  128  to measure drilling parameters, such as weight on bit, torque on bit, pressures, temperatures, flow rates, compositions, rotary speed, and/or other parameters of the field operation. Sensors (S) may also be positioned in one or more locations in the circulating system. 
     Drilling tools  106 . 2  may include a bottom hole assembly (BHA) (not shown), generally referenced, near the drill bit (e.g., within several drill collar lengths from the drill bit). The bottom hole assembly includes capabilities for measuring, processing, and storing information, as well as communicating with surface unit  134 . The bottom hole assembly further includes drill collars for performing various other measurement functions. 
     The bottom hole assembly may include a communication subassembly that communicates with surface unit  134 . The communication subassembly is adapted to send signals to and receive signals from the surface using a communications channel such as mud pulse telemetry, electro-magnetic telemetry, or wired drill pipe communications. The communication subassembly may include, for example, a transmitter that generates a signal, such as an acoustic or electromagnetic signal, which is representative of the measured drilling parameters. It will be appreciated by one of skill in the art that a variety of telemetry systems may be employed, such as wired drill pipe, electromagnetic or other known telemetry systems. 
     Typically, the wellbore is drilled according to a drilling plan that is established prior to drilling. The drilling plan typically sets forth equipment, pressures, trajectories and/or other parameters that define the drilling process for the wellsite. The drilling operation may then be performed according to the drilling plan. However, as information is gathered, the drilling operation may need to deviate from the drilling plan. Additionally, as drilling or other operations are performed, the subsurface conditions may change. The earth model may also need adjustment as new information is collected. 
     The data gathered by sensors (S) may be collected by surface unit  134  and/or other data collection sources for analysis or other processing. The data collected by sensors (S) may be used alone or in combination with other data. The data may be collected in one or more databases and/or transmitted on or offsite. The data may be historical data, real time data, or combinations thereof. The real time data may be used in real time, or stored for later use. The data may also be combined with historical data or other inputs for further analysis. The data may be stored in separate databases, or combined into a single database. 
     Surface unit  134  may include transceiver  137  to allow communications between surface unit  134  and various portions of the oilfield  100  or other locations. Surface unit  134  may also be provided with or functionally connected to one or more controllers (not shown) for actuating mechanisms at oilfield  100 . Surface unit  134  may then send command signals to oilfield  100  in response to data received. Surface unit  134  may receive commands via transceiver  137  or may itself execute commands to the controller. A processor may be provided to analyze the data (locally or remotely), make the decisions and/or actuate the controller. In this manner, oilfield  100  may be selectively adjusted based on the data collected. This technique may be used to optimize (or improve) portions of the field operation, such as controlling drilling, weight on bit, pump rates, or other parameters. These adjustments may be made automatically based on computer protocol, and/or manually by an operator. In some cases, well plans may be adjusted to select optimum (or improved) operating conditions, or to avoid problems. 
       FIG. 1C  illustrates a wireline operation being performed by wireline tool  106 . 3  suspended by rig  128  and into wellbore  136  of  FIG. 1B . Wireline tool  106 . 3  is adapted for deployment into wellbore  136  for generating well logs, performing downhole tests and/or collecting samples. Wireline tool  106 . 3  may be used to provide another method and apparatus for performing a seismic survey operation. Wireline tool  106 . 3  may, for example, have an explosive, radioactive, electrical, or acoustic energy source  144  that sends and/or receives electrical signals to surrounding subterranean formations  102  and fluids therein. 
     Wireline tool  106 . 3  may be operatively connected to, for example, geophones  118  and a computer  122 . 1  of a seismic truck  106 . 1  of  FIG. 1A . Wireline tool  106 . 3  may also provide data to surface unit  134 . Surface unit  134  may collect data generated during the wireline operation and may produce data output  135  that may be stored or transmitted. Wireline tool  106 . 3  may be positioned at various depths in the wellbore  136  to provide a survey or other information relating to the subterranean formation  102 . 
     Sensors (S), such as gauges, may be positioned about oilfield  100  to collect data relating to various field operations as described previously. As shown, sensor S is positioned in wireline tool  106 . 3  to measure downhole parameters which relate to, for example porosity, permeability, fluid composition and/or other parameters of the field operation. 
       FIG. 1D  illustrates a production operation being performed by production tool  106 . 4  deployed from a production unit or Christmas tree  129  and into completed wellbore  136  for drawing fluid from the downhole reservoirs into surface facilities  142 . The fluid flows from reservoir  104  through perforations in the casing (not shown) and into production tool  106 . 4  in wellbore  136  and to surface facilities  142  via gathering network  146 . 
     Sensors (S), such as gauges, may be positioned about oilfield  100  to collect data relating to various field operations as described previously. As shown, the sensor (S) may be positioned in production tool  106 . 4  or associated equipment, such as Christmas tree  129 , gathering network  146 , surface facility  142 , and/or the production facility, to measure fluid parameters, such as fluid composition, flow rates, pressures, temperatures, and/or other parameters of the production operation. 
     Production may also include injection wells for added recovery. One or more gathering facilities may be operatively connected to one or more of the wellsites for selectively collecting downhole fluids from the wellsite(s). 
     While  FIGS. 1B-1D  illustrate tools used to measure properties of an oilfield, it will be appreciated that the tools may be used in connection with non-oilfield operations, such as gas fields, mines, aquifers, storage or other subterranean facilities. Also, while certain data acquisition tools are depicted, it will be appreciated that various measurement tools capable of sensing parameters, such as seismic two-way travel time, density, resistivity, production rate, etc., of the subterranean formation and/or its geological formations may be used. Various sensors (S) may be located at various positions along the wellbore and/or the monitoring tools to collect and/or monitor the desired data. Other sources of data may also be provided from offsite locations. 
     The field configurations of  FIGS. 1A-1D  are intended to provide a brief description of an example of a field usable with oilfield application frameworks. Part of, or the entirety, of oilfield  100  may be on land, water and/or sea. Also, while a single field measured at a single location is depicted, oilfield applications may be utilized with any combination of one or more oilfields, one or more processing facilities and one or more well sites. 
       FIG. 2  illustrates a schematic view, partially in cross section of oilfield  200  having data acquisition tools  202 . 1 ,  202 . 2 ,  202 . 3  and  202 . 4  positioned at various locations along oilfield  200  for collecting data of subterranean formation  204  in accordance with implementations of various technologies and techniques described herein. Data acquisition tools  202 . 1 - 202 . 4  may be the same as data acquisition tools  106 . 1 - 106 . 4  of  FIGS. 1A-1D , respectively, or others not depicted. As shown, data acquisition tools  202 . 1 - 202 . 4  generate data plots or measurements  208 . 1 - 208 . 4 , respectively. These data plots are depicted along oilfield  200  to demonstrate the data generated by the various operations. 
     Data plots  208 . 1 - 208 . 3  are examples of static data plots that may be generated by data acquisition tools  202 . 1 - 202 . 3 , respectively; however, it should be understood that data plots  208 . 1 - 208 . 3  may also be data plots that are updated in real time. These measurements may be analyzed to better define the properties of the formation(s) and/or determine the accuracy of the measurements and/or for checking for errors. The plots of each of the respective measurements may be aligned and scaled for comparison and verification of the properties. 
     Static data plot  208 . 1  is a seismic two-way response over a period of time. Static plot  208 . 2  is core sample data measured from a core sample of the formation  204 . The core sample may be used to provide data, such as a graph of the density, porosity, permeability, or some other physical property of the core sample over the length of the core. Tests for density and viscosity may be performed on the fluids in the core at varying pressures and temperatures. Static data plot  208 . 3  is a logging trace that typically provides a resistivity or other measurement of the formation at various depths. 
     A production decline curve or graph  208 . 4  is a dynamic data plot of the fluid flow rate over time. The production decline curve typically provides the production rate as a function of time. As the fluid flows through the wellbore, measurements are taken of fluid properties, such as flow rates, pressures, composition, etc. 
     Other data may also be collected, such as historical data, user inputs, economic information, and/or other measurement data and other parameters of interest. As described below, the static and dynamic measurements may be analyzed and used to generate models of the subterranean formation to determine characteristics thereof. Similar measurements may also be used to measure changes in formation aspects over time. 
     The subterranean structure  204  has a plurality of geological formations  206 . 1 - 206 . 4 . As shown, this structure has several formations or layers, including a shale layer  206 . 1 , a carbonate layer  206 . 2 , a shale layer  206 . 3  and a sand layer  206 . 4 . A fault  207  extends through the shale layer  206 . 1  and the carbonate layer  206 . 2 . The static data acquisition tools are adapted to take measurements and detect characteristics of the formations. 
     While a specific subterranean formation with specific geological structures is depicted, it will be appreciated that oilfield  200  may contain a variety of geological structures and/or formations, sometimes having extreme complexity. In some locations, typically below the water line, fluid may occupy pore spaces of the formations. Each of the measurement devices may be used to measure properties of the formations and/or its geological features. While each acquisition tool is shown as being in specific locations in oilfield  200 , it will be appreciated that one or more types of measurement may be taken at one or more locations across one or more fields or other locations for comparison and/or analysis. 
     The data collected from various sources, such as the data acquisition tools of  FIG. 2 , may then be processed and/or evaluated. Typically, seismic data displayed in static data plot  208 . 1  from data acquisition tool  202 . 1  is used by a geophysicist to determine characteristics of the subterranean formations and features. The core data shown in static plot  208 . 2  and/or log data from well log  208 . 3  are typically used by a geologist to determine various characteristics of the subterranean formation. The production data from graph  208 . 4  is typically used by the reservoir engineer to determine fluid flow reservoir characteristics. The data analyzed by the geologist, geophysicist and the reservoir engineer may be analyzed using modeling techniques. 
       FIG. 3A  illustrates an oilfield  300  for performing production operations in accordance with implementations of various technologies and techniques described herein. As shown, the oilfield has a plurality of wellsites  302  operatively connected to central processing facility  354 . The oilfield configuration of  FIG. 3A  is not intended to limit the scope of the oilfield application system. Part, or all, of the oilfield may be on land and/or sea. Also, while a single oilfield with a single processing facility and a plurality of wellsites is depicted, any combination of one or more oilfields, one or more processing facilities and one or more wellsites may be present. 
     Each wellsite  302  has equipment that forms wellbore  336  into the earth. The wellbores extend through subterranean formations  306  including reservoirs  304 . These reservoirs  304  contain fluids, such as hydrocarbons. The wellsites draw fluid from the reservoirs and pass them to the processing facilities via surface networks  344 . The surface networks  344  have tubing and control mechanisms for controlling the flow of fluids from the wellsite to processing facility  354 . 
     Attention is now directed to  FIG. 3B , which illustrates a side view of a marine-based survey  360  of a subterranean subsurface  362  in accordance with one or more implementations of various techniques described herein. Subsurface  362  includes seafloor surface  364 . Seismic sources  366  may include marine sources such as vibroseis or airguns, which may propagate seismic waves  368  (e.g., energy signals) into the Earth over an extended period of time or at a nearly instantaneous energy provided by impulsive sources. The seismic waves may be propagated by marine sources as a frequency sweep signal. For example, marine sources of the vibroseis type may initially emit a seismic wave at a low frequency (e.g., 5 Hz) and increase the seismic wave to a high frequency (e.g., 80-90 Hz) over time. 
     The component(s) of the seismic waves  368  may be reflected and converted by seafloor surface  364  (i.e., reflector), and seismic wave reflections  370  may be received by a plurality of seismic receivers  372 . Seismic receivers  372  may be disposed on a plurality of streamers (i.e., streamer array  374 ). The seismic receivers  372  may generate electrical signals representative of the received seismic wave reflections  370 . The electrical signals may be embedded with information regarding the subsurface  362  and captured as a record of seismic data. 
     In one implementation, each streamer may include streamer steering devices such as a bird, a deflector, a tail buoy and the like, which are not illustrated in this application. The streamer steering devices may be used to control the position of the streamers in accordance with the techniques described herein. 
     In one implementation, seismic wave reflections  370  may travel upward and reach the water/air interface at the water surface  376 , a portion of reflections  370  may then reflect downward again (i.e., sea-surface ghost waves  378 ) and be received by the plurality of seismic receivers  372 . The sea-surface ghost waves  378  may be referred to as surface multiples. The point on the water surface  376  at which the wave is reflected downward is generally referred to as the downward reflection point. 
     The electrical signals may be transmitted to a vessel  380  via transmission cables, wireless communication or the like. The vessel  380  may then transmit the electrical signals to a data processing center. Alternatively, the vessel  380  may include an onboard computer capable of processing the electrical signals (i.e., seismic data). Those skilled in the art having the benefit of this disclosure will appreciate that this illustration is highly idealized. For instance, surveys may be of formations deep beneath the surface. The formations may typically include multiple reflectors, some of which may include dipping events, and may generate multiple reflections (including wave conversion) for receipt by the seismic receivers  372 . In one implementation, the seismic data may be processed to generate a seismic image of the subsurface  362 . 
     Marine seismic acquisition systems tow each streamer in streamer array  374  at the same depth (e.g., 5-10 m). However, marine based survey  360  may tow each streamer in streamer array  374  at different depths such that seismic data may be acquired and processed in a manner that avoids the effects of destructive interference due to sea-surface ghost waves. For instance, marine-based survey  360  of  FIG. 3B  illustrates eight streamers towed by vessel  380  at eight different depths. The depth of each streamer may be controlled and maintained using the birds disposed on each streamer. 
       FIG. 4  illustrates a flowchart of a method  400  for interpreting seismic data, according to an embodiment. In particular, the method  400  illustrated may be used for processing 3D seismic data with multiple machine learning techniques. In some embodiments, the method  400  can be implemented with any suitable computing device such as the computing system  901 A of  FIG. 9 , which is described in greater detail below. 
     At block  402 , the method  400  can acquire seismic data. The seismic data may be acquired by generating and recording seismic waves that are propagated through a subterranean domain (e.g., a subterranean volume), or reflected from reflectors (e.g., interfaces between different types of formations). The recording (or traces) can be accomplished using recording devices, such as geophones, hydrophones, or the like, as described above. 
     In one example, the seismic data may be received from receivers  372  as shown in  FIG. 3B . While being towed, the receivers  372  may continuously record the seismic data received from reflections  370 . The seismic data received by individual receivers  372  can be characterized according to a function of time and space. The time can represent the time at which the seismic data was received or acquired, and the space can indicate a geographic location or position where the seismic data was received or acquired. 
     In another example, the seismic data may be received from receivers  118  as shown in  FIG. 1A . In this example, sound vibration  112  generated by the source  110  reflects off horizons  114  in earth formation  116 . A set of sound vibrations may be received by sensors, such as geophone-receivers  118 , situated on the earth&#39;s surface. The seismic data received by the receivers  118  may be represented as a function of time and space. The time may represent the time at which the seismic data was received or acquired, and the space may indicate a geographic location or position where the seismic data was received or acquired. In one example, the seismic data can be previously recorded, whether in a marine or land environment, and retrieved from a storage device. 
     In some embodiments, the seismic data can be aggregated into three-dimensional (3D) seismic volumes that indicate rock formation characteristics of subterranean formations within various geographical areas. For example, the 3D seismic volumes can include seismic data indicating discontinuity patterns, which can be interpreted as horizontal and/or vertical fault lines. In some embodiments, the 3D seismic volumes can be interpreted with any suitable number of machine learning techniques as described in greater detail below in relation to blocks  404 - 408 . 
     At block  404 , the method  400  can further include combining inline probability values and crossline probability values generated by a first machine learning technique to form a merged data set. The inline probability values can indicate a likelihood of a fault residing in a vertical plane of seismic data. The vertical plane is parallel to the direction in which the seismic data was acquired. The crossline probability values can indicate a likelihood of a fault residing in a vertical plane of seismic data. The vertical plane is perpendicular to the direction in which the seismic data was acquired. In some embodiments, the inline probability values are represented as an inline prediction probability cube in which each data point indicates a probability that the data point is associated with a fault line. In some examples, each data point of the inline prediction probability cube can correspond to a different area within a three-dimensional region of a subterranean region. For example, the inline prediction probability cube can include probability values that indicate a likelihood that vertical cross sections of the three-dimensional seismic data include fault lines. The inline prediction probability cube can correspond to fault lines that are parallel to the direction in which the seismic data was acquired. 
     In some embodiments, the crossline probability values are represented as a crossline prediction probability cube in which each data point indicates a probability that the data point is associated with a fault line. In some embodiments, the crossline prediction probability cube corresponds to fault lines that are perpendicular to the direction in which the seismic data was acquired. 
     In some examples, the merged data set is calculated by applying any suitable function to the inline probability values and the crossline probability values. For example, the merged data set can be calculated with a maximum function, among others, based on a comparison of corresponding data points of the inline probability values and the crossline probability values. For example, a maximum function can be applied to data points from the inline prediction probability cube and the crossline prediction probability cube that correspond to the same location in a subterranean region. The maximum function can generate a combined or merged probability cube that is discussed in further detail below in relation to  FIG. 7 . 
     In some examples, at block  404 , the first machine learning technique can be trained to identify one or more vertical fault lines from a 3D seismic volume. For example, labeled vertical planes or slices of three-dimensional seismic data can be provided to the first machine learning technique. The labeled vertical planes can indicate data points corresponding to fault lines and data points that are false positive values, among others. In some embodiments, the first machine learning technique can be a neural network, a classification technique, a regression-based technique, a support-vector machine, and the like. In some examples, the first neural network can include any suitable number of interconnected layers of neurons in various layers. For example, the first neural network can include any number of fully connected layers of neurons that organize the seismic data provided as input. The organized data can enable visualizing a probability of a fault line within a vertical plane of the seismic data as described in greater detail below in relation to  FIG. 7 . 
     The first neural network can employ any suitable convolutional neural network techniques, encoding techniques, or clustering techniques such as k-means clustering, hierarchical clustering, and the like. In some embodiments, a convolutional neural network can include any suitable number of local or global pooling layers that can reduce the dimensions of the seismic data by combining output from neuron clusters at one layer into a single neuron in a subsequent layer. In some examples, the convolutional neural network can include computing a maximum value or an average value, among others, while pooling seismic data. For example, a maximum value from a cluster of neurons at a prior layer can be selected and used in a subsequent layer. In some examples, an average value from a cluster of neurons can be selected and used in a subsequent layer. 
     In some embodiments, each seismic data point can initially be placed in a first cluster, and the first cluster can be merged with additional clusters using a bottom-up approach. In another embodiment, the seismic data points can be included in a first cluster, and the first cluster can be split using recursive techniques as the neurons of the neural network move in a top-down approach. The seismic data points can be combined or split based on a dissimilarity value between the seismic data points. For example, the dissimilarity value can indicate a distance between two seismic data points or two sets of seismic data points. The distance can be calculated using any suitable technique such as a Euclidean distance, a squared Euclidean distance, a Manhattan distance, a Maximum distance, or a Mahalanobis distance, among others. In some embodiments, the first neural network can also include linkage criteria that specifies the dissimilarity of sets of seismic data as a function of pairwise distances of data points in the sets of seismic data. For example, the linkage criteria can be calculated using Maximum or complete-linkage clustering, Minimum or single-linkage clustering, unweighted average linkage clustering, weighted average linkage clustering, centroid linking clustering, or minimum energy clustering, among others. 
     At block  406 , the method  400  can include training a second machine learning technique based on a subset of labeled horizontal planes from the merged data set. In some examples, the second machine learning technique can be trained to identify one or more horizontal fault lines from a 3D seismic volume. The labeled horizontal planes used to train the second machine learning technique can indicate data points that correspond to horizontal fault lines and data points that are false positive values. In some examples, the false positive values do not correspond to a fault line despite a high probability value. In some embodiments, the second machine learning technique can be initiated or trained with a subset of horizontal planes of the combined or merged probability cube, or merged data set. 
     In some embodiments, the second machine learning technique can be a neural network, a classification technique, a regression-based technique, a support-vector machine, or any other machine learning technique. In some examples, the second machine learning technique can be smaller than the first machine learning technique and include fewer layers of neurons and/or fewer neurons per layer. In some embodiments, the neurons of the second machine learning technique may or may not be fully connected. 
     In some examples, the trained second machine learning technique can process the remaining horizontal planes of the merged data set. Furthermore, in some examples, the second machine learning technique can be trained with horizontal planes of seismic data from multiple seismic volumes. In some embodiments, an initialized or trained second machine learning technique can analyze the merged data set without detecting labeled horizontal planes of seismic data for the seismic volume being analyzed. For example, the trained second machine learning technique can process a merged data set of a seismic volume based on weights assigned to neurons in previous training iterations of the machine learning technique. In some embodiments, the output of the second machine learning technique can include a modified merged data set or modified probability cube that reflects a probability that each point in a vertical plane or a horizontal plane of seismic data corresponds to a fault line. In some examples, the output of the second machine learning technique can identify and remove false positive data values previously identified as fault lines. An example of output from the second machine learning technique is described below in relation to  FIG. 8 . 
     At block  408 , the method  400  can include generating a three-dimensional representation of the seismic volume based on the second machine learning technique. In some embodiments, the three-dimensional representation can include an indication of a three-dimensional fault structure within the 3D seismic volume. The three-dimensional fault structure, as discussed herein, can include any suitable number of vertical faults, horizontal faults, or a combination thereof. In some examples, the three-dimensional representation of the seismic volume can remove false positives unrelated to fault lines and connect horizontal and vertical fault lines. In some examples, the three-dimensional representation of the seismic volume can enable the selection of drilling plans for reservoirs corresponding to the seismic data. For example, the three-dimensional representation can indicate regions of a subterranean region to be avoided in conventional drilling due to likely fault lines. In some examples, the three-dimensional representation can indicate regions of a subterranean region to be utilized in unconventional drilling. For example, the identified faults can enable removal of additional oil and/or gas from a reservoir by allowing the oil and/or gas to travel through the faults and to become trapped in a reservoir. 
     In some embodiments, the three-dimensional representation of the seismic volume can be stored on a local computing device or transmitted to an external computing device for storage. In some examples, an alert can be generated based on the three-dimensional representation of the seismic volume and transmitted to equipment controlling a drill string. For example, the alert can indicate a horizontal and/or vertical change in direction of drilling based on identified horizontal and/or vertical fault lines. 
     The process flow diagram of  FIG. 4  is not intended to indicate that the operations of the method  400  are to be executed in any particular order, or that all of the operations of the method  400  are to be included in every case. Additionally, the method  400  can include any suitable number of additional operations. For example, the method  400  can include creating a three-dimensional subsurface model of subterranean rock associated with an oil and gas reservoir. The method  400  can also include selecting an oil and gas production plan based on the three-dimensional subsurface model. For example, the three-dimensional subsurface model can be used to indicate a location and size of a potential reservoir. Furthermore, the method  400  can include transmitting the oil and gas production plan to equipment to cause a retrieval of a resource from the oil and gas reservoir. 
       FIG. 5  illustrates a block diagram for interpreting 3D seismic data with machine learning techniques, according to embodiments herein. In some examples, a seismic volume  502  can include any suitable number of three-dimensional seismic data sets. In some embodiments, the three-dimensional seismic data sets can include any number of data points corresponding to crossline data values and inline data values. 
     In some embodiments, vertical fault lines  504  can be labeled within the seismic volume  502 . For example, any suitable subset of vertical planes of data from the seismic volume  502  can be labeled for vertical fault lines, false positive values, and the like. In some embodiments, the labeled vertical fault lines  504  can be provided to a first neural network (NN #1)  506 . As discussed above, the first neural network  506  can analyze the remaining vertical planes of the seismic volume  502  and generate output comprising inline prediction values  508  and crossline prediction values  510 . The inline prediction values  508  can include any suitable representation of data points indicating a likelihood or probability of fault lines in the inline vertical planes of the seismic volume  502 . The inline vertical planes can include a two dimensional vertical plane of the seismic volume  502 , wherein the inline vertical planes are parallel to the direction from which the seismic volume  502  was acquired. The crossline prediction values  510  can include any suitable representation of data points indicating a likelihood or probability of fault lines in the crossline vertical planes of the seismic volume  502 . The crossline vertical planes can include a two dimensional vertical plane of the seismic volume  502 , wherein the crossline vertical planes are perpendicular to the direction from which the seismic volume  502  was acquired. In some examples, the inline prediction values  508  and the crossline prediction values  510  can be represented as three-dimensional probability cubes in which each data point of the 3D probability cubes corresponds to a probability of a fault line at that data point. 
     In some embodiments, a merged prediction  512  is generated by combining the inline prediction values  508  and the crossline prediction values  510 . The merged prediction  512  can be generated with a maximum function or any other suitable function. For example, the inline prediction values  508  and the crossline prediction values  510  can be merged by creating a merged three-dimensional probability cube in which each data point is a maximum data point based on corresponding data points in the inline prediction  508  and the crossline prediction  510 . In some examples, the inline prediction values  508  and the crossline prediction values  510  can be merged with any other suitable function such as a minimum function, an average function, a mean function, and the like. 
     In some embodiments, a subset of horizontal planes of data  514  from the merged prediction  512  can be extracted, labeled, and used to train a second neural network (NN #2)  516 . In some examples, the number of horizontal planes of labeled data  514  used to train the second neural network  516  can be less than the number of vertical planes of labeled data used to train the first neural network  506 . For example, the second neural network  516  can be trained with as few as one or two horizontal planes of labeled data  514  from the merged prediction  512 . In some embodiments, the second neural network  516  can generate output such as the final prediction  518 . In some embodiments, the final prediction  518  indicates horizontal fault lines within the merged prediction  512 . In some embodiments, the second neural network  516  can identify and remove false positive data values that do not correspond to fault lines. Accordingly, the final prediction  518  can include fewer false positive data points, which can reduce the noise of the final prediction  518  to more clearly indicate vertical fault lines and/or horizontal fault lines. 
     In some examples, the final prediction  518  can be any suitable three-dimensional representation of data points indicating the probability of horizontal and/or vertical fault lines. The final prediction  518  can be displayed within a user interface, transmitted to an external device, and/or stored within any suitable computing device. In some embodiments, the final prediction  518  can be used to modify a drilling plan. The final prediction  518  is described below in relation to  FIG. 8 . 
       FIG. 6A  is an example of a horizontal plane of data from analyzed 3D seismic data. In some embodiments, the analyzed 3D seismic data corresponds to a merged probability cube based on an inline prediction probability cube and a crossline prediction probability cube. In some examples, the first machine learning technique can generate the inline prediction probability cube and the crossline prediction probability cube, which can be combined to form the merged probability cube based on any suitable function, such as a maximum function, among others. The horizontal plane of data  600  of  FIG. 6A  represents data points along an X axis and Y axis. The data points  602  and  604  can represent high probability data values that likely correspond to horizontal fault lines. The horizontal fault lines are represented as a pattern of discontinuity that can exist in a horizontal direction, a vertical direction, or any combination thereof. In some examples, the data points  606  and  608  can represent high probability data values that are likely false positives for horizontal fault lines because the data points  606  and  608  are isolated. 
       FIG. 6B  is an example of an interpretation of fault lines within a horizontal plane of data from analyzed 3D seismic data. In some embodiments, the analyzed 3D seismic data corresponds to a merged probability cube based on an inline prediction probability cube and a crossline prediction probability cube. In some examples, the first machine learning technique can generate the inline prediction probability cube and the crossline prediction probability cube, which can be combined to form the merged probability cube based on any suitable function, such as a maximum function, among others. In some embodiments, the data points  610  and  612  correspond to labeled horizontal fault lines. In some examples, the labeled horizontal fault lines are identified due to interconnectedness with surrounding high probability data points. For example, the data points  610  and  612  belong to a pattern of discontinuity that exists within the 3D seismic data. In some embodiments, a fault line can be predicted if the pattern of discontinuity exists within an area of the 3D seismic data that exceeds a predetermined threshold. In some embodiments, the data points  614  and  616  are considered to be false positive values that are not interconnected with neighboring high probability data points. Accordingly, in some examples, data points  614  and  616  are not identified as horizontal fault lines and can be discarded or ignored. In some embodiments, the probability values for data points  614  and  616  can be adjusted to a lower probability value of neighboring data points. 
       FIG. 7  is an example diagram depicting output from a first machine learning technique. In some embodiments, the output  700  represents a merged representation of a 3D inline prediction probability cube and a 3D crossline prediction probability cube. As discussed above, the output  700  from a first neural network can indicate a probability of vertical fault lines in a seismic volume. However, regions  702 ,  704 , and  706 , among others, can be noisy and include a higher percentage of false positive values. In some examples, regions  702 ,  704 , and  706  can also lack continuity and consistency. In some embodiments, the output  700  can be difficult to interpret due to the representation of a higher concentration of false positive data values and a lack of continuity. 
       FIG. 8  is an example diagram depicting output from a second machine learning technique. In some embodiments, the output  800  represents the probability of vertical fault lines and horizontal fault lines in a seismic volume. The second neural network can remove false positive data points from horizontal planes, which can remove noise from the output  800 . The second neural network can also improve the continuity and consistency of data values corresponding to fault lines. In some embodiments, regions  802 ,  804 , and  806  can include clear indications of fault structures within a seismic volume. In some embodiments, the output  800  can enable the detection of three-dimensional fault structures in a seismic volume by generating points within the regions  802 ,  804 , and  806  that indicate a high likelihood of a horizontal or vertical fault line at a particular location in a subterranean region. 
     In one or more embodiments, the functions described can be implemented in hardware, software, firmware, or any combination thereof. For a software implementation, the techniques described herein can be implemented with modules (e.g., procedures, functions, subprograms, programs, routines, subroutines, modules, software packages, classes, and so on) that perform the functions described herein. A module can be coupled to another module or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, or the like can be passed, forwarded, or transmitted using any suitable means including memory sharing, message passing, token passing, network transmission, and the like. The software codes can be stored in memory units and executed by processors. The memory unit can be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art. 
     In some embodiments, any of the methods of the present disclosure may be executed by a computing system.  FIG. 9  illustrates an example of such a computing system  900 , in accordance with some embodiments. The computing system  900  may include a computer or computer system  901 A, which may be an individual computer system  901 A or an arrangement of distributed computer systems. The computer system  901 A includes one or more analysis module(s)  902  configured to perform various tasks according to some embodiments, such as one or more methods disclosed herein. To perform these various tasks, the analysis module  902  executes independently, or in coordination with, one or more processors  904 , which is (or are) connected to one or more storage media  906 . The processor(s)  904  is (or are) also connected to a network interface  907  to allow the computer system  901 A to communicate over a data network  909  with one or more additional computer systems and/or computing systems, such as  901 B,  901 C, and/or  901 D (note that computer systems  901 B,  901 C and/or  901 D may or may not share the same architecture as computer system  901 A, and may be located in different physical locations, e.g., computer systems  901 A and  901 B may be located in a processing facility, while in communication with one or more computer systems such as  901 C and/or  901 D that are located in one or more data centers, and/or located in varying countries on different continents). 
     A processor can include a microprocessor, microcontroller, processor module or subsystem, programmable integrated circuit, programmable gate array, or another control or computing device. 
     The storage media  906  can be implemented as one or more non-transitory computer-readable or non-transitory machine-readable storage media. Note that while in the example embodiment of  FIG. 9  storage media  906  is depicted as within computer system  901 A, in some embodiments, storage media  906  may be distributed within and/or across multiple internal and/or external enclosures of computing system  901 A and/or additional computing systems. Storage media  906  may include one or more different forms of memory including semiconductor memory devices such as dynamic or static random access memories (DRAMs or SRAMs), erasable and programmable read-only memories (EPROMs), electrically erasable and programmable read-only memories (EEPROMs) and flash memories, magnetic disks such as fixed, floppy and removable disks, other magnetic media including tape, optical media such as compact disks (CDs) or digital video disks (DVDs), BLURAY disks, or other types of optical storage, or other types of storage devices. Note that the instructions discussed above can be provided on one computer-readable or machine-readable storage medium, or alternatively, can be provided on multiple computer-readable or machine-readable storage media distributed in a large system having possibly plural nodes. Such computer-readable or machine-readable storage medium or media is (are) considered to be part of an article (or article of manufacture). An article or article of manufacture can refer to any manufactured single component or multiple components. The storage medium or media can be located either in the machine running the machine-readable instructions, or located at a remote site from which machine-readable instructions can be downloaded over a network for execution. 
     In some embodiments, computing system  900  contains one or more interpretation module(s)  908 . In the example of computing system  900 , computer system  901 A includes the interpretation module  908 . In some embodiments, a single interpretation module  908  may be used to perform some or all aspects of one or more embodiments of the methods. In alternate embodiments, a plurality of interpretation modules  908  may be used to perform some or all aspects of techniques described herein. 
     It should be appreciated that computing system  900  is only one example of a computing system, and that computing system  900  may have more or fewer components than shown, may combine additional components not depicted in the example embodiment of  FIG. 9 , and/or computing system  900  may have a different configuration or arrangement of the components depicted in  FIG. 9 . The various components shown in  FIG. 9  may be implemented in hardware, software, or a combination of both hardware and software, including one or more signal processing and/or application specific integrated circuits. 
     Further, the steps in the processing methods described herein may be implemented by running one or more functional modules in information processing apparatus such as general purpose processors or application specific chips, such as ASICs, FPGAs, PLDs, or other appropriate devices. These modules, combinations of these modules, and/or their combination with general hardware are all included within the scope of protection of the invention. 
     Geologic interpretations, models and/or other interpretation aids may be refined in an iterative fashion; this concept is applicable to embodiments of the present methods discussed herein. This can include use of feedback loops executed on an algorithmic basis, such as at a computing device (e.g., computing system  900 ,  FIG. 9 ), and/or through manual control by a user who may make determinations regarding whether a given step, action, template, model, or set of curves has become sufficiently accurate for the evaluation of the subsurface three-dimensional geologic formation under consideration. 
     The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. Moreover, the order in which the elements of the methods are illustrated and described may be re-arranged, and/or two or more elements may occur simultaneously. The embodiments were chosen and described in order to best explain the principals of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.