Lithology - menu

The Lithology menu on the main screen looks surprisingly simple. However, CURVE 3.1 uses two implied types of AKAs.? The first is ‘AKA curve names’ which are alternative curve names associated with primary curve names or aliases as defined in the project’s CurveLogAliasFile.xlsx. The latter has been populated by Eucalyptus with over 1300 curve AKAs and Alias names. Curve also creates a list of missing curve names for the project that can be used to update the CurveLogAliasFile.xlsx manually.??

The second type of AKA names are alternative formation names such as the changing alternative tops along an angular unconformity or a diachronous contact (see the Strat-col spreadsheet). We plan to apply this in the future when Curve sets the top of the Zones when plotting data or when calculating tops in the various scripts for water saturation (SW_Fn) or VCL_Fn, or the final porosity (PHI_Fn). See the Script Menu.

The Lithology menu items are ‘Load core data’ and ‘Define Zones and AKAs’.? AKA curve names are substituted by the associated curve alias’. The latter allows the user to inspect and load Zones in the Strat_col.xlsx spreadsheet. The excel files (CurveLogAliasFile.xlsx and the Strat_col.xlsx spreadsheets) can also be directly created and edited in Excel. The Strat_col.xlsx is created for each project and stored in the project’s Dir (LAS) IN/databases directory. So is the CurveLogAliasFile.xlsx.

The Strat_col.xlsx spreadsheet defines the project Formation tops, its AKAs, as well as its Zones of curve analysis (see figure below which is defined for projects in Eastern Alberta). The Formation tops list the typical tops for the project. These tops were picked using Petra, AccuMap or similar software.? The AKAs are other tops defined to be equivalent to the Formation top (up to 11 AKAs). This is especially handy when the top of the formation in question is formed along an angular uniformity. E.g. in the Western part of the study area the Mannville top is formed by the McLaren or the top of a McLaren Incised Valley or more to the East by the Waseca Formation, etc. This complexity has currently not been implied in Curve 3.1. But it will be coming.

The Zones to which custom petrophysical parameters are assigned when? calculating curves (using Params.xlsx stored in LAS IN/databases), have a stratigraphic base and top and a possible offset value. For example, the top of the Mannville Zone can be set at 10m above the Mannville, or 5m below the Cummings.? In the future, if no Mannville lithostratigraphic Formation Name is defined for the well in question (See Fig 2), the formation AKAs are intended to provide an alternative Zone top or base. Curve applies changing Zone tops and Zone parameters in its Scripts (See Script Menu) by using formation AKAs. Applying changing parameters for individual stratigraphic zones when running scripts slows down CURVE compared with other software that do not automatically change parameters.

Since rock properties do both change with depth but also with project area, we spilt up regional studies into smaller project area(s) allowing project specific normalization, zone parameters and custom scripts (See Scripts Menu). Projects may also represent specific pools or oil or gas fields. All these features and concepts applied in Curve, allows a must more divers analysis with ever changing lithologies than most other existing software. That is why we also aim at integration of CURVE results in more general project software such as Petra or Geographixs.

These parameters are often defines in Xplots or lab work.

The Lithology menu has two main items:?

1.????? Load Core Data

2.????? Define Zones and AKAs

The Load Core Data submenu is further subdivided into:

·??????? (Load) Core Description

·??????? (Load conventional) Core Analysis????

Load Core Data creates a Core LAS file or ‘.cas’ file to integrate core data and core depth shifting value(s) (See Tools menu). The Core Shift also has submenus that allow several methods of core depth shifting, including graphical core shifting, the results of which are stored in the well’s ‘.cas’ file.

The core description is Eucalyptus specific again (Fig 4). It integrates conventional core analysis with detailed core description mineralogical data and Thin Section analysis results to create up to 54 core curves in the well's '.cas' file.

A ‘.cas’ file is like a ‘.las file’ but contains conventional core analysis data, core description data converted to 54 data curves at 0.1m depth increments just like wireline data curves are. We use the spreadsheet shown below (Fig. 4)? for the core description which also includes TS analysis data. The '.cas' files enable Curve to plot core data against wireline log data. In the future we intend to add mercury injection data. Mercury injection data can be critical for working with pore throat size and distribution data. It is essential for reservoir quality understanding.?

By now you may realized that Curve 3.1 has many unique features to integrate rock and wire log characteristics.? We call this calibrating logs to rocks or ‘From the rock to the log’ (Eucalyptus' corporate motto. This is (amongst other functionality) done with list boxes that show curves that wells of the current well list have in common. These lists may contain curves specifically in the DirIn (often assigned to the LAS IN directory), DirOut (often assigned to LAS OUT) and the curves in the ‘.cas’ files.? The ‘.cas’ files are also stored in the DirIn directory (often the project’s LAS IN directory in file explorer).? These curve lists are often displayed for curve selection in list boxes.? The curve-lists are also used in the background when various curves are automatically selected when running various scripts or in the tabs displaying Log Curves (DirIn curves), Calculated Curves (DirOut curves) and Core data (CorDir) in the Main Window (Fig. 5).

Please note that this tabs have many build in functionality activated by mouse clicks that are elsewhere documented (Fig 5).

The current well list is displayed on the Main Window (Fig 1 and Fig5) or on the Graphing Window (which is displayed when selecting Graphing on the main menu in Fig 1). Also the Well List frame has a lot of Mouse click functionality build in.