Explorational snapshot Non-conventional hydrocarbon in Hungary

Explorational snapshot Non-conventional hydrocarbon in Hungary Károly Kiss

2017.01.10 -11.

www.afki.hu

By definition , unconventional resources are ones that cannot be produced at economic flow rates or that do not produce economic volumes of oil and gas without assistance from massive stimulation treatments or special recovery processes and technologies. The difference between conventional and unconventional occurrences is either the nature of existence or the geological location. Unconventional oil and gas deposits require different and more complex production methods and additional upgrading to be usable as fuels. In essence, unconventional resources are more capital intensive (for development, production and upgrading) than conventional ones. The prospects for unconventional resources depend on the rate and costs at which these can be converted into quasi-conventional reserves.

(Source: ©2006 by Research Reports International, Inc.)

„Új kutatási irányok a földi energiaforrások hasznosításához kapcsolódóan” című szakmai tudományos konferencia

(Pollastro and others, 2003) Source: Courtesy of S. Holditch

„Shale Gas&Oil”

„Coalbed Methane”

Gas in sandstone reservoirs Generally thick reservoir sequences with lithological variation, high frequency thin bedding Generally over pressured

Gas/Oil in shale rocks, where the massive shale is the source and the reservoir of the hydrocarbon at the same time

Adsorbed, mainly methane gas connected to coal accumulations, situated mainly close to surface

Reservoir parameters are bad – typically the primary porosity is below 10%, permeability is below 0,1 mD

Significant heterogenetic structure Couple of percentage primary porosity, ultra low permeability <1,0 μD is typical

Production without stimulation is possible, but for commercial and economical production hydraulic fracturing requested

No flow without hydraulic fracturing No significant inflow just from the induced fractured zone

„Tight Gas”

Abnormal pressure regime

Generally low pressure system

The coal mostly fractured, the fractures contains water and gas together The key of production is the dewatering process


Typical Unconventional Accumulations

Value chain comparison Conventional case  





Relatively small(er) targets Conventional geological risk profile Well defined methods and tools Bookable, conventional reserve

Field Development

Non conventional case 

 



Up to several hundred or thousand km2 target Different risk profile Old-new technologies under development In place volumes, questionable bookable reserve

Drilling and stimulation program

Vertical Drilling Horizontal Drilling

Fracturing

Unconventional plays in the United States Major Basins

Marcellus

Conventional case 

  

One, relatively short development phase Well defined size One off cost for long period Low level or no risk


 

 

Continuous development for long time period Lot of wells and stimulation Continuous surface technological development Continuous investment Remaining risks

Continuous development

Production Conventional case 

 

High production rate for long period, then relatively quick drop Easy to operate One off abandonment






High production rate, then quick drop within short period Management and operation of huge number of wells with different production rates and pressures Continuous abandonment

Cumulative production profile


Exploration

Fayetteville Haynesville Barnett

4

(Pollastro andand others, 2003) (Pollastro others, 2003)


Main features of the unconventional accumulations


 Analysis/study


Top map of Preneogene basement

Pannonian Basin–Neogene Geological environment

1.8

5.3

Target Formations for Unconventional Hydrocarbon

Total thickness >5km

MMyears

Pannonian (brackish lacustrine, then fluvial)

11.6 13.0

Sarmatian (restricted marine) Badenian (marine)

16.3

Geology - base of the potential  Evaluated play types:  Shale gas – tight gas reservoirs in pannonian deep basin positions  Tight Gas in middle Miocene sediments

 Base conditions High sedimentation rate – thick sedimentary system Proved - hydrocarbon system – existing fields Presence of „tight” – „shale” reservoirs Early, low level of production from tight reservoirs without of massive stimulation  Proved, but volumetrically questionable source potential  Maturation/fluid type - working kitchen with mixed generation  Young, not fully consolidated reservoir system    

(Pollastro and others, 2003) Cross section - East-SouthEast Hungarian subbasins

 Challenges  Special - HPHT environment in the zones of unconventional reservoirs Possible top of accumulation

(Source: Horvath)

 Old wells – plenty of HC indication in the total formation column  No commercial flow during tests! No water inflow  Abnormal porosity and pressure regime  Non conventional reservoir conditions

2017.01.10 -11.

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Strengths of the initial deep basin model



Geological uncertainties: 

Lack of reliable data from the deepest part of sub-basins



Old dataset



Uncertain resource potential





Restricted inflow due to the low permeability or lack of natural fracture system

Technological challenges:  

High temperature and high formation pressure Requires special techniques for drilling, completion, stimulation

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Initial uncertainties

Main characteristics of Mid-Miocene play

Beru-1 summary:



Reservoirs: Thick Middle Miocen sandstone system Reservoir quality (core measurements) tight - low porosity-low permeability



Reservoir conditions - HPHT:

 

 

Pres. of deepest reservoir.: 57,1 MPa Temp. of deepest reservoir.: 200 0C



Fluid: good quality wet gas system



Initial test results (without any stimulation):

Beru-1 Core No 1-3. 100,00

Kl h (10-3µm2)

10,00

 

1,00

0,10

Low – non/sub commercial production Tight behaviour – high formation – low prod. Pressure



Actual state of well – Periodical production



Hydraulic fracturing treatment required

0,16

0,15

0,14

0,13

0,12

0,11

0,10

0,09

0,08

0,07

0,06

0,05

0,04

0,03

0,02

0,01

0,00

0,01

Porosity h (frac.)

►

Reservoir Quality (Core measurement result) ► Avr porosity: 8 % ► Avr. Perm.: 0,07-0,09 (10-3 m2)

Source: Unconventional exploration projects in the Central European environment, AIPN Conference, Vienna, 2012




Evaluation phase: Project preparation process 

Basin Evaluation Study  Decreasing of

Risks&Uncertainties  Checking of key elements High SCH

 Integration of available dataset

 3D basin modelling  Potential estimation

Low SCH

 Feasibility Study based on available dataset by Market Leader Service Companies

 Reservoir characterisation

 Stimulation technics,  Production forecast estimation

Source: Unconventional exploration projects in the Central European environment, AIPN Conference, Vienna, 2012

Drill&test


Top map of Preneogene basement

 Presence of Hydrocarbon has been proved in the tested reservoirs  Viability of the stimulation technology in HPHT environment has been proved  Flow-high initial rate has been proved by well tests  Huge in place volumes has been defined  All tested blocks converted into mining plot

Flowback on the Derecske area

 Initial models and technology has been tested

Non conventional mining plots

 Some domestic and international records:  deepest well in Hungary (Makó area)  highest temperature onshore frac operation in all Europe (Derecske area)

 Challanges ahead of any potentially successful non-conventional project:  Deep understanding of the static and dynamic behaviour of the reservoirs  Limited, or not existing long term production experience  No lateral wells, no technological optimization maximizing the production  Economic production still not proved 2017.01.10 -11.

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Source: MBFH

Resource Gas Conventional Nonconventional

In place volume 2015. 01. 01. MMm 3 185.474,96 3.923.342,47


Experiences of the Exploration stage


 When the reservoir permeability is poor hydraulic fracturing is a way to improve hydrocarbon production.  The process of hydraulic fracturing means that a fluid is pumped through the perforations into the formation together with propping material that secures the fracture keeping it open.  To fracture the formation the pressure has to reach the rock fracture gradient which requires very high pressure (700-1000bar) and to place the proper amount of proppant needs high volume (58000 litre/min) at that pressure. The technical result of the fracturing mainly depends on the proppant placement success.


Hydraulic fracturing


Reservoir characterisation from fracturing point of view

Frac Geometry

Chiswick Gamma 49/4a-C2 (49/4-1) 301.22 min 0.000

TVD m 3300

0.588

Proppant Coverage lb/ft^2

1.177

3350

1.765 2.353 2.942 3.530 4.119 4.707

3400

5.295 5.884

8500 9000 9500 1000010500 Stress (psi)

20

40

60 80 100 Fracture Penetration (m)

120

140


19


Monitoring of the fracs Microseismic

 Modelling fracture behaviour by using actual fracture dimensions Untitled

Shale

221.87 min

0.000 TVD m 4200

0.265

Proppant Coverage lb/ft^2

0.530

4250

0.795 1.060 1.325 1.590 1.855 2.121

Shale

4300

2.386 2.651

9500 10000 105001100011500 Stress (psi)

100

200 300 Fracture Penetration (m)

400

Candidate selection


Production Forecast


Result of Optimised Fracturing

Non technical challenges Public protests against unconventional – hydraulic fracturing, land issue…. Time-consuming regulation processes, specific regulations/recommendations on EU and local level (2010-) USD/bbl

Access to exploration licences (2010-2013)

USD/bbl

Forrás: MBFH

Oil Price drop (2014-)

Forrás: oil-price.net

Tight Gas fracturing – Development Phase

Köszönöm megtisztelő figyelmüket!

2017.01.10 -11.

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Explorational snapshot Non-conventional hydrocarbon in Hungary

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