Page 19 - Fundamentals of Gas Shale Reservoirs

Preface

The hydrocarbon source from conventional reservoirs is The aim of this book is to provide some guidance on the
decreasing rapidly. At the same time, global energy con- major factors involved in evaluating shale gas plays. The
sumption is growing so quickly that conventional reserves book is structured as follows:
alone cannot solely satisfy the demand. Therefore, there is a
pressing need for alternative sources of energy. As things Chapter 1 introduces shale gas from the point of view
currently stand from a technical viewpoint, the more expen- of its global significance, distribution and inherent
sive clean‐sustainable energy sources cannot compete with challenges.
the relatively cheap nonrenewable fossil fuels. Thus, the Chapter 2 discusses the environments suitable for organic
obvious immediate alternative energy source would be matter‐rich shale deposition.
found in non‐conventional oil and gas resources. These non‐ Chapter 3 assesses the organic geochemical properties of
conventional resources come in many forms and include gas shale gas resource systems.
hydrate, tar sand, oil shale, shale oil, tight gas sand, coal bed
methane, and of course, shale gas. Shale gas has for some Chapter 4 highlights important points about the sequence
time been the focus of gas exploration and production in the stratigraphy of shales.
USA and in other countries. Based on a recent EIA report, Chapter 5 discusses methods used for evaluating pore
there is an estimated 7299 trillion cubic feet (Tcf) of techni- geometry in shales.
cally recoverable shale gas resource to be found in some 137 Chapter 6 details the steps required for the petrophysical
basins located in 41 countries. analysis of shale gas plays.
Following notable successes in shale gas production in the Chapter 7 deals with pore pressure estimation of shales
USA, to the point where that country now produces more shale using conventional log data.
gas than gas from the conventional sources, other countries Chapter 8 covers shale gas geomechanics.
are pursuing the same course. Even so, in order to be success- Chapter 9 discusses the rock physics of organic‐rich
ful in the exploration and the development of shale gas plays, shales.
a number of important factors have to be taken into account:
Chapter 10 introduces passive seismic methods for non‐
conventional resource development.
• A vast knowledge of the different aspects of shales, such
as organic geochemistry, mineralogy, petrophysical Chapter 11 discusses gas transport processes in shale.
properties, shale geomechanics, reservoir engineering Chapter 12 reviews the critical issues surrounding the sim-
and so on, is required in order to properly evaluate and ulation of transport and storage in shale reservoirs.
map shale gas sweet spots in each sedimentary basin. Chapter 13 provides important information about the
• Shale gas environmental issues together with chal- performance analysis of shale reservoirs.
lenges such as the high water demands and possible Chapter 14 presents methodologies to determine original
contamination risks posed by hydraulic fracturing gas in place (OGIP), technically recoverable resources
fluids and waste have to be addressed. (TRR) and the recovery factor (RF) for shale reservoirs.