solutions to petroleum geological problems

Founded in1987 ENRES International in theNetherlands provides specialised consultancyservices for the petroleum industry.

As oil and gas exploration and production ismoving towards more mature phases,innovative new concepts are needed inpetroleum geology. To meet these challengingand rapidly changing demands put on thetechnical skills of petroleum geologists,ENRES focuses on the development ofinnovative methods, tools and concepts andis committed to R&D, with emphasis onsedimentary geology.

ENRES pioneered research into therelationship of sequence stratigraphicconcepts, cyclostratigraphy andsedimentology, and actively continues withresearch into methods to obtain improvednear-isochronous high-resolutionstratigraphic correlations in support ofthe construction of state-of-the-artexploration models, field development andreservoir characterisation.

An important product of ENRES’research is CycloLog , which is aninnovative, Windows -based softwarepackage that can obtain stratigraphicand sedimentological information fromlog data.

ENRES has been providing its servicesworldwide to the petroleum industry formore than 10 years with success. Theservices are always carried out in closecooperation with clients.

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WHAT IS CYCLOLOG ?

WHAT CAN CYCLOLOG DO?

GEOLOGICAL INTERPRETATION OF

GEOPHYSICAL LOGS

CycloLog is a Windows -based, interactive,user-friendly mathematical software tool. Itallows the user to characterise distinct partsof geophysical log data in an objective,quantitative and repeatable manner.

CycloLog is a specially designed toolboxfor the geological interpretation ofgeophysical logs. It contains a number oflog transforms that can be used instratigraphic and sedimentary faciesanalysis. Some of these transformsoperate in the depth domain, while otherstransform the data from the depth domainto the depth-wave number domain. Oneof the specific features of CycloLog isthat all transform operations allow acontinuous analysis in depth.

The trend towards more cost-efficienthydrocarbon exploration, fielddevelopment and production requires adetailed and accurate understandingof the geology of the subsurface.ENRES’ approach to this challenge isto provide a tool, CycloLog ,whichallows the geologist to obtain anaccurate overview of the subsurfacethrough a PC-based analysis ofgeophysical logs. In addition, the toolis cost-efficient and user-friendly, andhas operational features to ensure asteep learning curve.Geophysical log data provide an excellentbasis for computer applications forgeological interpretation. Log data meet theessential requirements for effectivesampling such as continuity, resolution andresponse to features of depositionalconditions. Furthermore, the number ofdata points from logs is very large incontrast to fossil abundance data orgeochemical data.

in situ

CycloLog incorporates a number of routinesor tools for the transformation of logs. Theseroutines give the user relevant informationneeded for a whole range of geologicalinterpretations.

CycloLog supports and enhances solutionsin the following fields of geology:

Seismic stratigraphy

Sequence stratigraphy

Cyclostratigraphy

Chronostratigraphy

Lithostratigraphy

Electrofacies / Lithofacies

Sedimentary facies

Petrophysical attributes

EDGE ENHANCEMENT

MEDIAN FILTER

DERIVATIVE

AVERAGE

POROSITY(DENSITY/SONIC)

MILANKOVITCHCYCLICITY MODELLING

(MIMOD)

LOG FREQUENCYSIMULATIONS

(SIMOD)

MULTI-LOGCLUSTER ANALYSIS

2D / 3D CLUSTERCROSS PLOT VIEWS

FORCED LOGCLUSTER ANALYSIS

(FORCING CLUSTER FROMCORED TO NON-CORED WELLS)

MAXIMUM ENTROPYSPECTRAL ANALYSIS

(MESA)

INTEGRATED PREDICTIONERROR FILTER ANALYSIS

(INPEFA)

PREDICTION ERRORFILTER ANALYSIS

(PEFA)

GR-INDEXVSH (in version 2.1)

N/G AND THICKNESS(USING CUTOFF VALUES)

VOLUMETRIC ANALYSIS(IN VERSION 2.1)

MATH STUDIOCOMPLEX MATH

FUNCTIONSe.g TOC calculations from logs

(IN VERSION 2.1)

FALSE COLOURLOG DISPLAY(IN VERSION 2.1)

CROSS CORRELATIONOF LOG PATTERNS AND

PROCESSED LOGPATTERNS

LOG MULTIPLICATION

LOG DIVIDE

LOG ADD

LOG SUBTRACT

LOG LOGARITHMIC

LOG INTEGRAL

LOG EXPONENTIAL

ROOT MEAN SQUARE

STANDARD DEVIATION

PROBABILITY DENSITY

REFLECTIVITY

ACOUSTIC IMPEDANCE

SEISMIC SYNTHETICS

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BASIC TOOLS ADVANCED TOOLS

CYCLOLOG TOOLBOX

The toolbox consists of basic and advanced tools.The basic tools incorporate elements of basicmathematics and statistics. The advanced toolsconsist of more complex mathematics and anumber of time-series analytical algorithms.

The routines can be used in practically unlimitedcombinations as all the transform operations arealways displayed in depth. All the results of thecalculations are displayed on screen and areavailable for immediate geological interpretation.All transformed logs can be exported in ASCIIformat.

The user can assign geological boundaries onscreen together with their labels. All depth dataof the boundaries can be saved in ASCII andimported into any spread sheet for furtherevaluation. Fonts and colours can be changed.

CycloLog has two specially designed analyticalalgorithms:

Spectral transform using MaximumEntropy Spectral Analysis (MESA)

Multi-log cluster analysis to differentiategeophysical lithofacies

One of the unique features of CycloLog is that all computationsare displayed as log transforms in depth.

Log transforms are logs whose pattern has been modified byprocessing, such as math calculations or spectral analysis.

Log transforms operate in the depth domain as well as in thedepth-wave number domain.

CycloLog versionsVersion 2.0R: December 1999Version 2.1B: November 2000Version 2.1R: January 2001

Version 3.0B: May 2001

Tentative program of

CYCLOLOG OBJECTIVES

ME

TH

OD

S/

CO

NC

EP

TS

Stratal Patterns / Zonation Classification Petrophysical Atttributes Depth-Time Conversion Multi-Well Correlation Well-Seismic Integration

Sequence StratigraphyCyclostratigraphy

Sequence StratigraphyCyclostratigraphy

Chronostratigraphy Near-SynchronousStratigraphic Correlation

Framework

Inter-Well Stratigraphic andFacies FrameworkSedimentary Facies

PetrophysicsSedimentary Facies

Electro-Facies

Lithostratigraphy

VISUAL ANALYSISOF LOGS / MANUALASSIGNMENT OFBREAKS ORBOUNDARIES

AUTOMATEDASSIGNMENT OFINTERVALSUSING CLUSTERANALYSIS

ATTRIBUTEGENERATION

CROSSCORRELATIONAND LOGSHIFTING

MILANKOVITCHCYCLICITYMODELLING

GENERATION OFSEISMICSYNTHETICSIN DEPTH

CORRELATION OFWELL DATA TOSEISMICATTRIBUTES

PREDICTION OFELECTROFACIESUSING VELOCITYSURVEYS(incl. Neural network)

ATTRIBUTEANALYSIS

STRATIGRAPHICCLUSTER OF LOGSAUTOMATEDASSIGNMENT OFBREAKS ORBOUNDARIES

INTERACTIVEVISUAL CHECKSAND MANUALDEFINITION OFZONES

VOLUMETRIC CALCULATIONS

Original Logs Cluster Analysis

Forced-ClusterAnalysis

Transformed Logs

Single logs

Overlays of multiplelogs

Shale Volume (V )SH

Porosity

Log Statistics

Net/Gross

Probability Density

Detection ofM-cycles for thePaleozoic, Mesozoicand Tertiary

Estimation of theNet Duration

Estimation of theNet AccumulationRate

Correlation oforiginal logs

Correlation oflog transforms

Calculates acousticimpedance andreflectivity

Generates seismicsynthetics in singleand multi-tracepattern

Single and multiplelogs

Single and multiplelog transforms

2D and 3D clustercross plot diagrams

Imposing a clustermatrix to other wells

Basic log transforms

Spectral transforms oflogs (MESA)

Advanced transformsof logs (PEFA/INPEFA)

MATH STUDIO

FALSE COLOUR DISPLAY

MAXIMUM ENTROPYFFT

HADAMARD-WALSH

WAVELETCONTINUOUS SPECTRAL ANALYSIS

SPECTRAL TRANSFORMSVersion 2.0

Version 2.1

Version 3.0

OBJECTIVES AND USED METHODS /

CONCEPTS

CycloLog was designed primarily forgeologists in support of the need to enhanceand facilitate the geological interpretationof geophysical logs.The design of the program consists thereforeof a number of relevant objectives with whichthe geologist has to deal in interpreting thesubsurface:

Well zonation and characterisation ofstratal patterns.

Petrophysical attributes.

Depth-time conversion

Multi-well correlation

Well-seismic integrationClassification

Recognition of boundaries and depositionaltrends in sequence stratigraphy andcyclostratigraphy. Hierarchical pattern ofboundaries, changes in basin accommodationversus depositional patterns.

Determination of electrofacies units throughlithological log analysis. Inter-active calibrationof the electrofacies units with lithofacies andsedimentary facies from cores. Prediction oflithofacies in non-cored wells by using thecalibrated electrofacies units.

Calculation of petrophysical parameters forgeological interpretations. Porosity patterns forinstance can be plotted against lithofaciesvariability or systems tracts in a sequencestratigraphic framework.

Depth to time conversion is carried out withthe presence of Milankovitch cycles. TheMilankovitch periodicities can be recognisedby a special routine in the program.Subsequently, Net Accumulation Rates per Kaand Net Time Durations of pre-definedintervals can be estimated.

A cross correlation routine is available forthe correlation of original logs andlog transforms.

Seismic synthetics can be generated throughthe calculation of acoustic impedanceand reflectivity. The seismic synthetics aredisplayed in depth and can be correlatedwith lithofacies successions or sequencestratigraphic patterns

Depth positionand GR-log value

at cursor line

Density-neutronoverlay

Mirror imageof GR-log

Sonic logElectrofaciesdisplay with

GR-log outline

INPEFA logtransform, displayingaccommodation vs.

deposition

Assignment ofboundaries coal

poroussand

progradationaltrend

Cursor line

Position ofthe cursor

CYCLOLOG THE USER-FRIENDLY WORKING

PLATFORM FOR PETROLEUM GEOLOGISTS

CycloLog is specially designed for fast andeasy handling of log transform operations. Alloriginal logs and log transforms can be displayednext to each other for an immediate overview andcomparison of the log expressions. Some of theoperational features can be summarised asfollows:

Fast displays of original logsand log transforms

Vertical scale and the horizontalscale of each log can beset and saved by the user

Easy generation and adjustmentof multi-log overlays, e.g forneutron-density combinations

Cursor line extends over thedisplayed logs. Depth position andlog value are displayed.

Boundaries can be drawn on screen.Boundary labels can be defined,modified or deleted. All boundarydepths can be saved in an ASCII file.

All the displayed logs and logtransforms can be edited in an outputmenu and printed.

DerivativeEdge

EnhancementFilter size 3m

AverageFilter

Filter size 3m

MedianFilter

Filter size 3m

WigglerGR

MirrorGR

ORIGINAL LOGS LOG TRANSFORMS

MedianFilter Analysis

AverageFilter Analysis

SMOOTHINGLOG FILTERS

Edge EnhancementFilter Analysis

DerivativeFilter Analysis

ENHANCEMENTLOG FILTERS

Inputoffilte

rw

indow

siz

eLOG FILTERS

Log filters may be used for theenhancement of the pattern of theoriginal logs. Log pattern enhancementmay support the visual correlationof wells.

The smoothing log filters tend to “block”the log patterns, while enhancementlog filters will display the higherfrequency pattern of the log.Log filters are generally used incombination with other log transformoperations.

Density-neutronoverlay

Thorium-Potassiumratio

divide Th by K logs

Acoustic Impedancecurve, divide

RHOB by DT logs

Mirror imageof GR-log

Sonic logElectrofacies

cluster analysisof density-neutron

high Th/Kratios

porous sands

MATHEMATICAL CALCULATIONS WITH LOGS

A number of basic and advanced mathematicalfunctions has been incorporated in the program.Mathematical operations can be performed witheach log in a fast and easy way. The followingmathematical operations can be performed:

Multiply logs

Divide logs

Add logs

Subtract logs

Integral calculation of logs

Logarithmic calculation of logs

Exponential calculation of logs

Basic Math

Advanced Math

Using “Divide logs” for spectral logsproduces a ratio curve which may giveinformation on the lithologicaldevelopment

The combination of log ratio plots andlog overlays of the density and neutronmay be useful for having an overviewon the lithological or porositydevelopment in a well.

GR-log histogram SONIC-log histogram

GR-log SONIC-log

LOG STATISTICS

A number of statistical operationsfor the quantification of a singlelog has been included in theprogram. The interval can bedefined by the user. The followingstatistical analyses can be made:

The average value

The Root-Mean-Squarevalue (RMS)

The Standard Deviation(STANDARD)

Histograms of single logs canbe generated for a user-defined interval. The histogramsplot the log values againstfrequency.

SEISMIC SYNTHETICS FROM ACOUSTIC IMPEDANCE

ACOUSTIC IMPEDANCEdensity

sonic

REFLECTIVITYdata - data(N) (N+1)

data + data(N) (N+1)

CALCULATE SEISMICSinput seismic wavelength

SEISMIC SYNTHETICS FROM SONIC LOG

INVERTED SONIC1

sonic

REFLECTIVITYdata - data(N) (N+1)

data + data(N) (N+1)

CALCULATE SEISMICSinput seismic wavelength

SEISMIC SYNTHETICS FROM DENSITY LOG

DENSITY LOGREFLECTIVITY

data - data(N) (N+1)

data + data(N) (N+1)

CALCULATE SEISMICSinput seismic wavelength

Density-neutronoverlay

Mirror imageof GR-log

Sonic logElectrofaciesdisplay with

GR-log outline

Seismicsynthetics in

multi-trace mode

INPEFA logtransform, displayingaccommodation vs.

deposition

SEISMIC LOG CALCULATIONS -

SEISMIC SYNTHETICS

Seismic synthetics can be generated fromthe acoustic impedance, sonic and density.The seismic synthetic display is in the depthdomain and can be correlated with theoriginal logs as well as the log transforms.

N/G calculation withcutoff GR-log value

of 30 APIN/G = 15.97

Total thickness = 30.3 m

N/G calculation ofporous sandN/G = 46.4

Total thickness = 88.2 m

PETROPHYSICAL ATTRIBUTES

Petrophysical attributes are used tosupport the geological interpretation oflogs, and to evaluate the relationshipbetween petrophysical parametersand geological features.

Attribute generation

Attribute analysis

GR/Th-index

Log statistics

Sonic / density derivedporosity

Net/Gross calculations

Single log histograms

MESA SPECTRUM BANDSWITH DIFFERENT WINDOW SIZES

MESAGR/W30ACO=8m

MIRRORGR

MESAGR/W40ACO=9m

MESAGR/W50

ACO=10m

FREQUENCY RANGELOW HIGH

0.5 WINDOW = 15 m

SPECTRUM BREAK

��� WAVE LENGTHsmalllarge

K = WAVE NUMBERsmall large

HIGH AMPLITUDE (RED) = PRONOUNCED CYCLICITY

LOW AMPLITUDE (YELLOW) = WEAK CYCLICITYNO AMPLITUDE (BLUE) = NO CYCLICITY OR NOISE

SPECTRUM BAND AMPLITUDE

LOW FREQUENCY / LARGE = TO THE LEFT OF SPECTRUM BAND SCALE�

HIGH FREQUENCY / SMALL = TO THE RIGHT OF SPECTRUM BAND SCALE�

CYCLE HIERARCHY

IN GEOLOGY = MISSING SECTIONS, CONDENSED SECTIONS, STACKED EROSIONAL SURFACES,LARGE-SCALE CHANGE IN DEPOSITIONAL PATTERN, LOG DATA ERRORS

POSITION OF BREAK IN THE DEPTH SCALE = 0.5 WINDOW SIZEDEPTH SHIFT RELATED TO WINDOW SIZE

SPECTRUM BREAKS (Cycle Interval Boundaries / CIB)

SPECTRAL TRANSFORM OF LOGS

Spectral transform of logs is uses a specially-designed version of Maximum Entropy Analysis(MESA). The program is a predictive tool in whichpart of a series of data points is analysed in order toattempt to predict the next point in the series.Essentially the analysis is performed on a portion of thedata series. In a downhole log data series, this portionis known as the window of analysis.

Window size is defined by the user. A cyclepattern or spectrum and prediction errorvalue is produced for that window. Theanalysis is then repeated on another, over-lapping portion of the data series.

INFORMATION BAR

A= 6.94m

D

C

E

WAVELENGTH =APPROX. 6.9m

RATIOMATCH

NUMBER

NETACCUMULATION

RATE

GEOLOGICALPERIOD

MESA CURSOR

MILANKOVITCHRATIOS

MILANKOVITCHPARAMETERS

USED CODES

MILANKOVITCHPERIODICITIES(TRIASSIC)

A

A

A4

A4

C

C DB

E

E

F

F

DECREASEINCREASE

NET ACCUMULATIONRATE (N)

413 Ka 100 Ka

1 0.37 0.21 0.184.13

37.0 Ka 21.0 Ka 18.0 Ka

ECCENTRICITY OBLIQUITY PRECESSION

USING THE MESA CURSOR FORPREDICTING MILANKOVITCH

CYCLES

SPECTRAL TRANSFORM OF LOGS -

MILANKOVITCH CYCLICITY PREDICTION

Prediction of M-cycles is part of the spectraltransform operational algorithm. The predictedM-periodicities from the Carboniferous to thepresent have been stored in the memorydataset of the program.

We use these predicted values to derive theratios between ancient climatic cycles andthen compare those ratios between the cyclewavelengths detected by MESA. This is doneinteractively on screen with the program.

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NEGATIVE PREDICTED ERRORVALUE / FREQUENCY DISCONTINUITYPRODUCED BY A JUMP FROM HIGH TOLOW GR VALUES

ACCOMMODATION INCREASE < SEDIMENT SUPPLY

POSITIVE PREDICTED ERRORVALUE / FREQUENCY DISCONTINUITYPRODUCED BY A JUMP FROM LOW TOHIGH GR VALUES

ACCOMMODATION INCREASE > SEDIMENT SUPPLY

PREDICTED TOP CARBONIFEROUSOR BASE ROTLIEGEND

PREDICTED STRATIGRAPHICBREAKS OR EROSIONAL SURFACES

PREDICTED STRATIGRAPHICBREAKS CAUSED BY MAJORFLOODING SURFACES

PEFAGR/MF7

PEFAGR/MF5

PEFAGR/MF3

PEFAGR/MF1

MIRRORGR

SEDIMENT DYNAMICSEROSIONAL HIATUS

CORRELATION LEVEL

EUSTATIC CHANGES

SUB-REGIONAL REGIONAL

EUSTATIC CHANGES / TECTONICS

LOCAL

PREDICTION ERROR FILTER ANALYSIS(PEFA)

Prediction Error Filter Analysis (PEFA) isbased on the comparison of measured logvalues and predicted log values. If weassume a certain predictability in (part of)the dataset, this predictability may beexpressed in terms of a prediction filter.This filter, when applied to the log valueswithin a depth window, will predict the logvalues just outside of that depth window.

If a prediction filter that was derived for aspecific part of a dataset is applied toanother part of the dataset, and thedifference between predicted and measuredlog values is determined, this differencecan be used to quantify how well the twolog-parts resemble each other.

Thus high output values of PEFA canoften be found to correspond to suddenchanges in log characteristics.These changes may be related togeological events, such as changes inclimate or basin dynamics.

0 +5 0.4 0.6 0.8 1.0-5

MAINEROSIONALSURFACE

OTHER MAJOREROSIONAL SURFACES

MAIN FLOODINGSURFACE

DECREASE OF EROSIONALSURFACES / INCREASE OF

ACCOMMODATION

NEGATIVE ORTHICKENING-UPWARD

TREND

INPEFACumulative differencebetween the predictedlog values and actual

log values

INTEGRATED PREDICTION ERRORFILTER ANALYSIS (INPEFA)

The INPEFA curve is the integration ofall PEFA values. INPEFA therefore isrelated to PEFA and represents thecumulative difference between thepredicted log values and actual logvalues.

High PEFA values will be presented asa major change in the INPEFA pattern.These major changes are defined as

.Cycle Interval Boundaries (CIB)

A stacked succession of negativePEFA values will show a negative or,in geological terms, a thickening-upward or progradational trend.Positive PEFA values will show apositive or retrogradational trend.

The negative trends are separated fromthe positive trends by major CIB’s.

INPEFA shows the following features:

A distinct hierarchical cyclicpattern of sedimentarysuccessions.

Enhances the sequencestratigraphic or cyclostratigraphicinterpretation of a well.

Geological events, such assequence boundaries and floodingsurfaces are clearly displayed.

Depositional trends - negativetrends (to the left) are relatedto progradational / aggradationaldepositional systems, whilepositive trends (to the right) arelinked to retrogradationalsystems.

Electrofacies fromthe cluster analysisof GR, RHOB and

NPHI

INPEFA ofthe GR-log

Cluster matrix display

Cluster parameters input

NON-HIERARCHICAL MULTI-LOG

CLUSTER ANALYSIS

The non-hierarchical multi-log clusteranalysis includes a number ofoperational routines which enablethe user to define a number of inputparameters. These input parametersenhance the results of the clusteranalysis and may also recognisediscrete horizons such as paleosols orthin coal layers.

In addition, a whole range of routines,such as changing the cluster colours,editing the interpretation labels, a 2Dand 3D cluster cross plot display areavailable to the user.

GR RHOB

NPHI

DT

INPEFA - GR

300 1.95

0.45

140

-0.50 0.55300 3.05

-0.15

40

(ACC>SED)(ACC<SED)

GEOLOGICAL EVENTINDICATING A CHANGE

IN DEPOSITIONALPATTERN

BASE WESTPHALIAN B

GEOLOGICAL EVENTINDICATING THE ONSET

OF A SAND-PRONEDEPOSITION

BASE WESTPHALIAN C

TRANSGRESSIVE BOUNDARYSURFACE (TBS)

TRANSGRESSIVE BOUNDARYSURFACE (TBS)

"PROGRADING"

SAND-PRONE

INTERVAL

WESTPAHLIAN B SANDS

"RETROGRADATIONAL"

TRANSGRESSIVE

SHALE-PRONE AND

COAL-BEARING INTERVAL

WESTPHALIAN B / MAURITS FM

TOP CARBONIFEROUS

GEOLOGICAL EVENTIN THE ROTLIEGEND

COPPER SHALEZEZ1K

BASE WESTPHALIAN D

D

C

A

B

LOWER SLOCHTERENTREND

AMELANDTREND

UPPER SLOCHTERENTREND

SILVERPITTREND

MID-CFLOODING

MID-BFLOODING

MID-AFLOODING

EXAMPLES OF CYCLOLOG SINGLE WELLINPEFA LOG TRANSFORMS ANDINTERPRETATIONS

ROSLL

ZEZ1K

Cycle Interval Boundary (CIB)

Well data courtesy NITG-TNO

ZEZ1K ZEZ1K

ROSLL

ROSLLLOWER SLOCHTEREN

TREND

AMELANDTREND

UPPER SLOCHTERENTREND

SILVERPITTREND

MID-CFLOODING

MID-BFLOODING

MID-AFLOODING

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Memory 32 Mb RAM (minimum)

Colour graphics card with 8 Mb memory

Recommended 17 inch SVGA 1024 x 768, 75Hz and 0.28 dpi colour monitor

Intel Pentium II 300mHz or higher

Windows 95 / 98 / NT 4.0 or higher

PLATFORM(S)

HARDWARE REQUIREMENTS

RECOMMENDED PLOTTERS

EXAMPLE OF CYCLOLOG WELL CORRELATIONUSING INPEFA LOG TRANSFORMS

Well data courtesy NITG-TNO

EPSON Stylus 1520

HP Designjet 750C

APPROX. 10 km

RESERVOIR CORRELATION AND CHARACTERISATION

USING INPEFA FREQUENCY CURVES

CORRELATION OF INDIVIDUAL SAND UNITS

Ruysdaellaan 33712 AP Huis ter Heide

Netherlands

Phone: 31.30.693 1922Telefax: 31.30.693 2149

E-mail: enres@euronet.nlWeb: www.enres.nl

United Kingdom

StrataData Ltd.17 The Bothy, Ottershaw ParkChobham Road, OttershawSurrey KT 16 0QGUK

Contact: David SmithE-mail: smithdg@cwcom.net

Phone/Fax: 44.1932.872041

Netherlands

Panterra Geoconsultants B.V.Veerpolder 52361 KX WarmondNetherlands

Contact: Greg van de BiltE-mail: g.van.de.bilt@panterra.nl

Phone: 31.71.301 9307Fax: 31.71.301 0802

United States

Digital Formation6000 East Evans Avenue, Suite 1-400Denver, Colorado 80222-5415USA

Contact: Christian P. BachE-mail: Christian.Bach@DigitalFormation.com

Phone: 1.303.770-4235Fax: 1.303.770-0432

Indonesia

PT. GEOSERVICES (Ltd.)Jl. Taman Matraman Timur 11Jakarta 10320Indonesia

Contact: Ms. Fitri NurrahmahE-mail: software@geoservices.co.id

Phone: 62.21.390-4118Fax: 62.21.319-6295

United States

Contact: Neil MooreE-mail: seacon@scscomputers.com

Seacon Computer Systems, Inc.11381 Meadowglen, Suite FHouston, Texas 77082-2647USA

Phone: 1.281.293-9565Fax: 1.281.293-9504

Egypt

Earth Resources Exploration (EREX)El Salam TowerMisr Helwan Agricultural RoadMaadi-CairoEgypt

Phone: 20.2.525-3989Fax: 20.2.525-4277

Contact: Nazih TewfikE-mail: erex@ritsec1.com.eg

ENRES has cooperative agreements with a number ofconsulting companies. They act as re-sellers for CycloLogand we support each other in consulting services.

Please contact the company in your region for moreinformation on CycloLog or consulting services