1

UNCONVENTIONAL OIL AND GAS

RESERVOIRS

PETE 612

FALL 2010

Lecture 11 A

“Tight Gas Resources, Reserves, and Production”

Walter B. Ayers, PhD

Tight Gas Topics

• Economic importance of tight gas sands

• Locations of USA tight gas basins

• Definitions of tight gas sands

• Controls on tight gas occurrence and

producibility

• Primary controls

• Secondary controls

• Models of tight gas reservoirs occurrence

• Characteristics of tight gas reservoirs

• Production and reserves

• Drilling, completion, stimulation techniques

• Challenges

2

Economides and Oligney, 2000

GLOBAL ENERGY DEMAND TO 2020

U.S. Historic and Forecast Unconventional

Gas Production

EIA: Annual Energy Outlook 2005 with Projections to 2025, DOE Report #: DOE/EIA-0383(2005)

3

Region

Coalbed

Methane

(Tcf)

Shale

Gas

(Tcf)

Tight-Sand

Gas

(Tcf)

Total

(Tcf)

North America 3,017 3,842 1,371 8,228

Latin America 39 2,117 1,293 3,448

Western Europe 157 510 353 1,019

Central and Eastern Europe 118 39 78 235

Former Soviet Union 3,957 627 901 5,485

Middle East and North Africa 0 2,548 823 3,370

Sub-Saharan Africa 39 274 784 1,097

Centrally planned Asia and China 1,215 3,528 353 5,094

Pacific (Organization for Economic

Cooperation and Development) 4702,313

705 3,487

Other Asia Pacific 0 314 549 862

South Asia 39 0 196 235

World 9,051 16,112 7,406 32,560

From Rogner, 1997

World Unconventional Gas Resources

Total U.S. Dry Natural Gas Discoveries per

Exploratory Gas Well Completion, 1977-2006

From EIA, 2007

Bcf

Dis

co

vere

d p

er

Exp

lora

tory

Well

Year

4

From Kuuskraa, 2007

Changes in Productivity of Unconventional

Gas Wells, 1996 - 2005

5

From Kuuskraa, 2007; with data from EIA

U.S. Gas Production, 1996 and 2006

U.S. Unconventional Gas Production, 1996 and 2006

From Kuuskraa, 2007

Ga

s P

rod

uc

tio

n (

Tc

f )

1.58x

1.64x

3.66x

6

From Kuuskraa, 2007

To

tal N

um

ber

of

Wells

U.S. Unconventional Gas Wells Drilled, by Year

http://www.adv-res.com/pdf/Tight-Sand-Basins.pdf

U.S. TIGHT SAND BASINS

7

http://www.adv-res.com/pdf/Annual-Tight-Sand-Production.pdf

Historic Tight Gas Production, by Basin

From Kuuskraa and Banks, 2007

(59%)

(65%)(71%)

1.58x

8

Comparison of Unconventional Gas Resource

Estimates, U.S. Lower- 48 States (Tcf)

From Kuuskraa and Banks, 2007

From Kuuskraa, 2007

To

tal N

um

ber

of

Wells

U.S. Unconventional Gas Wells Drilled, by Year

9

10

Henry Hub Natural Gas Prices,

2005 - 2009

Why has gas price

Dropped in the past

year?

What are the impacts of gas prices on the operators and their activities?

Henry Hub is the pricing point for natural gas futures contracts traded on the New York Mercantile

Exchange (NYMEX). It is a point on the natural gas pipeline system in Erath, Louisiana.

http://research.stlouisfed.org/fred2/series/GASPRICE

http://www.oilnergy.com/1gnymex.htm

Henry Hub

Natural Gas

Prices

2010

11

NEXT:

“Primary Origins of Tight Gas Sands”