METHODS OF DEFLECTING A WELLBORE con't 4

Steerable Motor Assembly

Effect of bend housing angle on build rate and bit side load

 

Effect of hole erosion on build rate

 

Baker motor stabilization configuration 

• The expected build rate will depend upon the motor configuration

  

• Build rate for a fully stabilized motor assembly 
• Can rotate to a bend of 1.5o

  

•     Build rate for a fully partially stabilized motor assembly Can rotate to a bend of 1.5o

 

Build rate for a slick motor assembly

Can rotate to a bend of 1.6o

 

The build rate will depend upon

-Motor stabilization

-Hole size

-Motor size

-Distance from bit to bend

-Stabilizer diameter (undergage)

-Etc.

Rotary steerable 

Steerable without sliding (100% rotation)

Can change both inclination and direction 

Steerable motor in the slide and rotate mode

Theoretically in the rotary mode, it will drill straight ahead

Limitations of steerable 

motors in the slide mode

 

•   Sometimes difficult to slide due to hole drag and stabilizers hanging up
•   Difficulty maintaining orientation especially as the well gets deeper and the drill string gets smaller
•   More difficult to maintain orientation with a PDC bit because of higher bit torques versus bit weight   

•   Poor hole cleaning while in the slide mode.  Rotation helps clean the hole
•   Lower effective penetration rate.  Harder to keep a constant weight on bit in slide mode.  Time is spent orienting the motor.
•   Higher wellbore tortuosity
•   Differential pressure sticking
•   Build rate is formation sensitive  

Limitations of steerable motors in the rotate mode  

•   Higher vibrations lead to motor and MWD failure
•   Accelerated bit wear
•    Poor hole quality for logs (sometimes)
•   Poor performance in air  

The rotary steerable system address some but not all of the limitations  

These rotary steerable concepts were patented in the 1950’s, but the design is being used today

Guidance systems were required to make them work

 

Rotary steerable systems being designed and used today

 

Schlumberger rotary steerable system

 

Gyrodata rotary steerable system

 

Economics of rotary steerable

 

Rotary steerable can improve hole cleaning with 100% rotation

Rotary steerable assemblies have the potential to reduce overall dogleg severity

Rotary steerables can still drill directionally when the pipe will not fall into the hole with its own weight (steerable motor cannot slide)

 

Service companies eventually want to get the rotary steerable to drill the hole without interference from the surface

The directional program is placed in the MWD

The computer computes a position and determines what it needs to do to get to the target and takes the appropriate action

 

All the drilling contractor does is add drill pipe like drilling a vertical well

It would not be applicable where the directional target changes based on geosteering data

Equation for calculating toolface angle to change direction and azimuth

 

Need to change inclination from 14o to 25o and change azimuth from 10o to 48o  

 

METHODS OF DEFLECTING A WELLBORE

METHODS OF DEFLECTING A WELLBORE con't

 

METHODS OF DEFLECTING A WELLBORE con't 2

METHODS OF DEFLECTING A WELLBORE con't 3

mappingbook (William A. Thomas)

William A. Thomas

With a Foreword by
Philip E. LaMoreaux

American Geological Institute
In cooperation with
Association of American State Geologists
Geological Society of America
National Park Service
U.S. Geological Survey

 value of geologic maps

geologic maps are the single most important and
valuable tool we have for understanding and living
with the Earth around us. Their usefulness is so broad
that geologic maps are the most requested scientific product
produced by state and federal geological surveys. Kentucky’s
experience with geologic maps exemplifies their value and
utility.

download for free

contents

Using Geologic Maps for Habitat
Prediction Tim Connors 28
2 Geologic Maps and Cave Resources
Kentucky Geological Survey 30
3 Geologic Maps and Mineral Resources
Jonathan G. Price 32
4 Geologic Map Delineates Landslide
Hazards Gregory C. Ohlmacher,
James R. McCauley, John C. Davis 34
5 Geologic Map Depicts Sinkhole
Susceptibility David K. Brezinski,
James P. Reger, Gerald R. Baum 36
6 Geologic Maps Identify Landslide
Hazards Russell W. Graymer,
Richard J. Pike 38
7 Geologic Map Helps To Protect
Groundwater William A. Thomas,
Willard E. Ward, W. Edward Osborne 40
8 Geologic Map Guides Earthquake
Damage Prediction Scott D. Stanford 42
9 Geologic Maps Identify Post-Wildfire
Hazards Vince Matthews, David Gonzales 44
10 Geologic Maps Guide the Delineation
of Ecosystems Scott Southworth,
Danielle Denenny 46
11 Geologic Map Delineates Volcanic Hazards
Joe D. Dragovich, David K. Norman 48
12 Geologic Maps Delineate Sand and Gravel
Resources Beth L. Widmann, Jim Cappa 50
13 Geologic Maps Identify Could Resources
and Past Mining Clifford H. Dodge 52
14 Geologic Map Guides Transportation
Planning Edward C. Murphy 54
15 Geologic Map Aids Mitigation of
Earthquake Damage George Plafker 56
16 Using Geologic Maps To Find
Groundwater Peggy S. Johnson 58
Glossary 60
Credits 61
State Geological Surveys 62
Index 63
AGI Environmental Geoscience Program
& AGI Foundation 64

Geological Structures and Maps

Geological Structures
and Maps
A PRACTICAL GUIDE

Geological Structures
and Maps
A PRACTICAL GUIDE
Third edition
RICHARD J. LISLE
Cardiff University

 

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Contents

Geological Maps 

 Uniformly Dipping Beds 

 Folding 

 Faulting 

 Unconformity 

 Igneous Rocks 

 Folding with Cleavage
Further Reading

Preface

GEOLOGICAL maps represent the expression on the earth’s
surface of the underlying geological structure. For this
reason the ability to correctly interpret the relationships
displayed on a geological map relies heavily on a knowledge
of the basic principles of structural geology.
This book discusses, from first principles up to and
including first-year undergraduate level, the morphology of
the most important types of geological structures, and
relates them to their manifestation on geological maps.
Although the treatment of structures is at an elementary
level, care has been taken to define terms rigorously and in
a way that is in keeping with current professional usage. All
too often concepts such as ‘asymmetrical fold’, ‘fold axis’
and ‘cylindrical fold’ explained in first textbooks have to be
re-learned ‘correctly’ at university level.
Photographs of structures in the field are included to
emphasize the similarities between structures at outcrop
scale and on the scale of the map. Ideally, actual fieldwork
experience should be gained in parallel with this course.
The book is designed, as far as possible, to be read
without tutorial help. Worked examples are given to assist
with the solution of the exercises. Emphasis is placed
throughout on developing the skill of three-dimensional
visualization so important to the geologist.
In the choice of the maps for the exercises, an attempt
has been made to steer a middle course between the
artificial-looking idealized type of ‘problem map’ and real
survey maps. The latter can initially overwhelm the
student with the sheer amount of data presented. Many of
the exercises are based closely on selected ‘extracts’ from
actual maps.
I am grateful to the late Professor T.R. Owen who
realized the need for a book with this scope and encouraged
me to write it. Peter Henn and Catherine Shephard of
Pergamon Books are thanked for their help and patience.
Thanks are also due to Vivienne Jenkins and Wendy
Johnson for providing secretarial help, and to my wife Ann
for her support.