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Software - HIIP

HIIP™ is a depth structure uncertainty and volumetric

calculator package for fast and easy computation of field

and prospect volumes. HIIP™ is of value whether working in

exploration, appraisal or field development.

Running under Windows operating systems HIIP is a Java-based software package. Easy to use and portable, HIIP can be run on laptops or desktop PCs and is ideal for rapid testing of volumetric scenarios. Whether in the office or data room, HIIP is an essential tool for geoscientists, working on anything from new ventures to mature assets. HIIP allows the user to create or load existing depth maps and generate multiple geostatistical realisations of depth structure in order to estimate the full range of depth and volumetric uncertainty over a particular area of interest. A comprehensive set of geological scenarios can then be tested very quicky to come up with GRV Uncertainty distributions. Play and prospect risk factors and probability distributions for petrophysics, fluids and recovery can be set in order to make probabilistic calculations of HIIP (Hydrocarbons Initially In Place) and Reserves. Features of the software include: Single and Multi-layer depth conversion Automated fitting of complex DC functions Automatic closure & spillpoint calculation Connectivity & fault-seal sensitivity: Test and constrain Amplitude conformance with structure Fast geological scenario testing Unbiased geostatistical ranges Non-conditional simulation for exploration targets Reliable uncertainty recognition and estimation Prospect evaluation and reporting HIIP from Earthworks Reservoir Developed over the last decade and a proven technology within Earthworks Reservoir’s consultancy portfolio, HIIP™ was commercialised in 2008. Providing a statistically robust tool with a simple and efficient workflow, HIIP™ has moved from strength to strength. Continuous dedicated development has seen HIIP™ gain and hold market position as recognised technology for depth conversion and volumetric uncertainty uniquely combining advanced depth conversion with stochastic subsurface analysis. Utilising a modular workflow and project tree format, HIIP™ has been designed with you the user in mind. Focussed and customer driven development result in a smooth, efficient and intuitive tool. With a streamlined licence structure, HIIP™ delivers a sound technology without the worry or complexity of varied licence options. Workflow Management The interface is built around a tree structure, rather like a file manager. Each branch of the tree represents a scenario. New scenarios can be created by cut and paste, either of an entire tree or selectively to add new components. Scenarios can have multiple branches, thus allowing what-ifs? to be constructed, for example attaching several different reservoir layer models to a gross rock volume geological scenario and calculation. Data Import and Export Depending on the analysis, the user can choose to load a number of different data types including point sets, grids, well locations, formation tops, faults and polygons. These data may be used to constrain volumetric computations, be used as input for mapping or geostatistical simulation within HIIP or simply for display purposes to represent a prospect and associated licence boundary and well data. Many data types are supported, both for input and export. Popular grid formats include: Generic X Y Z loader Zmap (LandMark) CPS-3  (GeoQuest) Irap Classic (Petrel) Isatis Utility Capability HIIP has a comprehensive set of Utility functions for both data preperation and QC. These include: Gridding & Utility: Median filters can now be applied to a grid to remove anomalous values with changing the structure of the grid A brand new morphological operations module has been added allowing the user to process and filter noise from amplitude grids o Options such as ‘close’ and ‘open’ give the user flexibility to remove noise and anomalous values from the fringes of amplitude anomalies while also accounting for amplitude area lost due to tuning/ thinning of the reservoir Upgrades and improvement to Petrel data bridge Development of grid cleaning/homogenisation tool which takes any grids which may have different extent, sizes etc and creates a clean, common geometry stack of grids with user defined truncation with layer priorities.  This tool is designed to provide significant upgrade to grid preparation for depth conversion  and (externally) seismic inversion. Proportional horizon generation tool to generate sub-horizons between horizons. DC - Depth Conversion Module HIIP has a comprehensive and fully featured Depth Conversion (DC) module available as an option.  The DC module has data analysis and function fitting capability combined with a convenient tool for comparing depth conversion cases and identifying optimal solutions.

HIIP™ v2.6.1 New Features:

Significant performance improvements throughout the depth conversion and improved management if very large well data sets Apparent velocity grids for any interval/method can now be generated for any depth conversion function and saved to the work tree, intended for use in 3rd party depth conversion packages An intermediate tie can now be applied for a V0+Kz. Shift the preceding horizon by the mean of the depth residuals at the well to ensure the velocity at top of layer  is more accurate Residual reporting inlcudes well XY coordinates Major upgrade to automatic fitting of V0+kZ velocity functions.  Legge&Rupnick fitting has been extended and is no longer restricted to layer1, so automatic V0+kZ function fitting allowed for any layer o Function fitting can be optimised from any horizon as reference level, not just datum, so functions can fitted with reference to seabed/mudline for example o Error residual data and optimal V0 as a function of velocity gradient k stored and can be displayed for every layer V0+kZ function o If user over-rides k value in any layer, program can still identify V0 from error residual function and populate interface with optimal V0 to match user-defined k. Additional statistical information on crossplots including coincident sample mean calculations Residual data at any horizon in depth conversion can be stored to the HIIP data tree as a point set for further analysis or kriging View/Export instantaneous velocity slice through any depth conversion function as % proportion of slice position with layer.  Particularly useful for QC of function methods such as V0+kZ. View/Export velocity difference map across depth conversion interval boundaries to QC for velocity inversions etc. Unique neighbourhood kriging has been included, particularly designed for well datasets and offering significant performance upgrades when kriging residuals Kriging now recognises horizon null nodes in residual kriging, greatly improving efficiency HIIP’s depth conversion module allows the user to input TWT grids and depth convert them using a range of different methods from a wide variety of velocity data types as shown below. The DC module allows the user to associate the well formation tops (and well times) with the TWT grids and perform back-calculation from grids to the formation top intersection location with the grid. These data are presented in the Data Tables as the layer and horizon based times and depths for QC and analysis using the cross-plot and regression tools. Multiple depth conversion cases can be specified and compared side-by-side, changing the layer model and the functions or velocity grids within each layer. The depth conversion residuals and associated statistics are all compared simultaneously.

Available Functions

HIIP has a broad range of available functions, and for some types of relation these are expanded by also including reverse regressions and by substituting well or seismic times.  The basic methods can be summarised as: Constant Velocity average o Vwell o Vpseudo Velocity Map – Imported Velocity Map – Wells o Vwell o Vpseudo Depth | Time & Time | Depth o Vpseudo Velocity | Time & Time : Velocity o Vwell o Vpseudo Dual Velocity V0+kZ Instantaneous Velocity o Mid-point method o Legge & Rupnick

V0 + kZ Instantaneous Velocity

The linear instantaneous velocity function is a common and widely used approach.  The increase of velocity with depth is assumed to approximate a compaction function with velocity increasing as porosity is progressively lost. The instantaneous velocity is given by: v=V_0+kZ And the depth conversion formula by: z_base=z_top e^kΔt+(V_0/k)(e^kΔt-1) There are a number of approaches to estimating the intercept (V0) and gradient (k) terms.  Sonic logs can be used, this tends to give a higher estimate of gradient, k.  Sonic logs are not currently available in HIIP,  however, an externaly derived estimate of V0 and k can easily be input manually in HIIP. HIIP offers two methods of estimating the parameters V0 and k.  Both of these use time-depth pairs as the input.   The first approach is the Mid-Point Method.  This is a traditional method based on the linear regression of the interval velocity against the mid-point depth of layer.  The regression line gives an estimate of the parameters.  The graphical display for this approach is a standard crossplot for each horizon or interval in the HIIP data analysis screens and an option to use this approach is provided on the V0+kZ edit panel.  The mid-point method has the advantage of a graphical plot to evaluate the data quality and is easy to use.       Regression of velocity plotted against mid-point depth There are a number of published methods for solving by least squares for V0 and k.  The method used in HIIP finds the optimal solution to the travel time-depth pairs (not the velocity) by iterating on k and then solving forV0.  The method was published by Legge & Rupnik (1943).  The original published method solves for a single layer with datum at the top of layer, HIIP uses a more general approach which can solve for any interval and using any other horizon as the reference or datum level for V0.  A further advantage of L&R is the reporting of the error as a function of k. The left image below shows the V0+kZ function edit panel and the right image below the error as a function of k.                                    V0+kZ function edit panel (left) and Legge & Rupnick depth error as function of gradient k (right) Note that the error function indicates that the depth error is fairly constant for a range of values of gradient k from about 0.6 to 0.9.  For each value of k HIIP holds a corresponding optimal V0 calculated by the L&R algorithm.  This means that if the user over-rides the value of k using the user defined checkbox and then ticks the “Calculate V0” button, the optimal V0 for a given k solving for the time-depth pairs for the depth conversion can be found automatically.  An additional option available to the V0+kZ function is the ability to remove any depth conversion shift arising at the top of the interval from the depth conversion of the shallower intervals.  By checking this option on the mean residual is subtracted prior to computing the thickness through the current V0+kZ interval.  The depth conversion Tie screen allows the comparison of the resultant residual grids and depth converted grids both before and after tie to the wells. Selected depth conversion cases can then be saved to the main HIIP tree for subsequent analysis in the GS and/or VPP modules or they can be exported in industry standard formats and utilised within other frameworks. Key Features Single and multilayer depth cases Deviated wells supported Back calculation at wells from grids Horizon and Layer views o Data analysis and crossplotting o QC travel times using seismic and CVL times o Linear regression and function definition o Well selections/masking o Large set of DC functions o Sophisticated automatic function fitting o Large set of QC and error analysis tools Side-by-side comparison of multiple depth conversion Cases with residuals and statistics tabulated for easy comparison QC Tools Input data can be quality controlled and inspected, and function validity reviewed, using the crossplot tool available on each horizon and layer table in the Data Tables section of the DC tree.  Additionally, for each method there are tools for reviewing the implied velocity grid associated with the method.  This includes: Apparent Velocity Grid Instantaneous Velocity Grid Slice Velocity Difference at Layer Top Grid Gradient Error Misfit (V0+kZ Function) Dual Velocity function curve GS - Geostatistics Module The GS geostatistics object is used for computing SGS geostatistical simulations of the top base structure or thicknesses. The HIIP™ GS module is designed to be simple and easy to use for non-geostatisticians, requiring just 4 simple steps via an on-screen wizard. HIIP™ computes multiple realisations using the sequential Gaussian simulation (SGS) algorithm and stores the results ready for subsequent analysis in the VPP module. Grids created in HIIP™ can be exported to other packages through the industry standard formats supported. Geostats SGS simulation includes support for faults. The GS module also includes an automated tool for directional anisotropic variogram analysis and for variogram model fitting. The GS module now also includes simulation of thickness grids either as imported tied grids or as variability around a user-specified mean thickness value. When used with well data, the realisations are automatically tied to the well control points. However, geostatistical realisations can also be computed in the absence of wells, creating multiple geostatistical realisations for exploration scenarios too. Geostatistical capability includes: Variogram Analysis and Modelling Kriging and Standard Deviation Estimation with full support for faults SGS conditional or non-conditional simulation with full support for faults       VPP - Volumetric Post Processing

HIIP™ v2.6.1 New Features:

Area depth information can now be calculated based on hydrocarbon column height as well as contact depth New Probability Distribution Functions (PDF), have been added so that area depth calculations on either contact or column height do not need to be treated exclusively as a uniform distribution o ‘Slice’ through your prospect and see the area-depth information obtained using functions such as normal, log-normal and triangular o A brand new beta function has been added o Advantageous to use as it is a bounded distribution (unlike normal etc.) A new layer model allows the stacking of as many reservoir or waste zone intervals as required for the prospect, allowing the building of a complex reservoir model for volumetric analysis The VPP module is the core interactive tool which allows the user to tackle any volumetric scenario. The geoscientist can specify “what if” scenarios taking into consideration possible fault seal, spillpoint, amplitude maps, contacts and stratigraphic trapping mechanisms as well as defining multiple reservoir and waste zone layers offset from the mapped horizon to the top reservoir. The grid input to VPP may be an existing deterministic top structure grid loaded to HIIP, a depth converted grid generated within HIIP or you may have run multiple geostatistical realisations on either input using the GS module supplied with HIIP. Whichever way, VPP rapidly computes volumes for your selected scenario. By setting up multiple Vpp objects, different geological assumptions can be modelled and stored. The scenarios you model in VPP are limited only by your imagination. You may have an oil or gas contact identified in a drilled well which you want to input. It may be a prospect yet to be drilled. You may have an oil-down-to (ODT) or water-up-to (WUT). All these (and more) can be incorporated into the scenario modelling . With a yet to drill target you can automatically compute the gross rock volume associated with the lowest closing contour. From the maximum fill you can then reduce the volume to account for partial fill by adjusting the contact or using the automatic area-depth slicing. To run an automatic spillpoint (lowest closing contour) calculation the user defines seed points. An Include seed is a point inside of the field or prospect outline and an Exclude seed is a point beyond the field or prospect. A seed can be a well or a control point digitized on the screen interactively. After specifying include and exclude positions the connectivity and autospill functions determine the maximum possible size of the prospect. With multiple realizations the batch controller rapidly applies your settings to all realizations, automatically computing the volumes. Automatic Lowest Closing Contour (Spillpoint) Verification against known contacts and automatic rejection of invalid solutions Connectivity and Compartmentalisation Calculations Fault Seal Constraints Isoprobability Closure Mapping Area Depth realization displays WUT/ODT Constraints Column Height Constraints Contact PDF uncertanty Gas column height proportions Amplitide conformance statistics and constraint Volume calculations can include multiple polygons, volume reporting can then be per polygon as well as total volumes. Reservoir layering can be introduced through the layer model option. The user can specify a constant or can use a thickness grid. Waste zones can also be included, to account for offset between the mapped structure and the top of reservoir / porous zone. Any number of reservoir or waste zones can be stacked. Base reservoir grid is also offered which allows truncation in the connectivity calculations and provides the means for defining stratigraphic traps. HIIP also allows sets of geostatistical realisations for the reservoir thickness, waste zone / or base reservoir. Stratigraphic traps can also be defined using faults as barriers.   Using multiple geostatistical realisations as input the batch controller will automatically process all realisations and report the volumes from which P90, P50 and P10 probabilities can be calculated. In addition the Isoprobability closure map can be generated, showing the probability at any grid node of drilling within the closure. These maps, being based on connectivity, can also be used to estimate probability of structural dip compartmentalisation of the prospect or field. PEP - Prospect Evalaution and Risking PEP is a fully functional 1D Monte Carlo engine. In HIIP™ PEP can be used in a traditional manner as a standard risk and uncertainty module, with user supplied distributions for porosity, net:gross, saturation, GRV and so forth, but it can also be linked directly to the grid data through Vpp. With GRV often the largest contribution to HIIP uncertainty, it allows information to be taken directly from the prospect map, with geostatistical uncertainty, into the PEP model. Merging Geostatistics and Prospect Evaluation The key concept in HIIP™ is to link the traditional 1D Monte Carlo Prospect Evaluation approach to the grids and maps produced during any sub-surface analysis. Prospects identified on digital grids can be input directly to the Prospect Evaluation. By using the output from geostatistical uncertainty modelling the GRV uncertainty can be passed to the Prospect Evaluation as a statistical distribution of gross rock volume. In turn, the prospect parameters such as reservoir thicknesses, waste zone thicknesses and base reservoir grids can be used to modify volumetric calculations on the grids.


HIIP™ includes the play and prospect chance factors in the reporting of reserves and these parameters are set in the PEP module. Different companies will have different numbers of and names for these chance or “risk” factors. The play and prospect configuration shown below is quite common but HIIP™ is adaptable and companies can define their own standard risk factors within the software using an xml template. The user can have as many or as few factors as required and can name them according to their corporate conventions. The PEP module allows the user to set up probability distribution functions (PDF) for each of the parameters that contribute to the calculation of in- place hydrocarbons and reserves. All common PDF types are supported and distributions may also be truncated. The GRV distribution can also be used directly from a Vpp analysis based on multiple realisations, allowing the geostatistical and Vpp spillpoint results to be seamlessly passed into the final prospect evaluation. After defining the required input PDF’s, the PEP module then runs a Monte Carlo analysis to combine the PDF’s and reports final distribution functions for hydrocarbons in-place and for reserves. The reporting is also split by gross and net interest in the in-place or reserves, defined by the production working interest parameter set by the user for each analysis. PEP also allows a large amount of text, context and geological information to be attached to each prospect evaluation and this can then used to generate summary reports containing all relevant information as well as the hydrocarbon volume calculations. Different reserve categories can be selected and, like the chance factor categories, these can be configured to suit the customer’s requirements.  HIIP™ - Petrel™ Data Link Plug-in Readily integrate HiiP™ within your Petrel™ workflows with the HiiP™ - Petrel™ data link plug-in and simply transfer data between the two environments; allowing you to fully analyse the uncertainty of your prospects. Launch the HiiP™ executable pathway from within Petrel™ or independently as a standalone tool from your desktop. The settings are clearly outlined within a pop-up wizard which details the port configuration and IP. The user can then effectively import and export data between HiiP™ and the Petrel™ environments. Licencing is fully managed by the HiiP™ licence server to provide simple licence control Independent licencing means the licence can be utilised with or without Petrel™. Strengthen and improve your workflow efficiency with the Petrel Data Link Plug-in and analyse uncertainty of your prospects. •        Readily integrate and utilise HiiP™ within Petrel™ •        Simply transfer data between the two environments •        Strengthen and improve the efficiency of your project workflow •        Straightforward licence control We hope you found this overview of HIIP interesting and useful. If you have any further queries or wish to find out about the software release status, licensing or pricing please send an e-mail to:                                                    or call +44 (0) 1224 619 300
EARTHWORKS reservoir
HIIP - Realising the prospects
Grid export and view options Final Depth Map Residual Error Grid test Vpp PEP Depth Conversion Geostatistics Volume Uncertainty GRV  Uncertainty Risked Volumes Uncertainty Risking Seismic TWT Grids/Maps Depth Grids/Maps
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