Book reviews

Fine-Grained Turbidite Systems. Edited by Arnold

H. Bouma and Charles G. Stone. 342 pages, Index,

CD-ROM included. AAPG Memoir 72 ± SEPM Special

publication no. 68. ISBN: 0 89181 353 5.

Perce Allen, introducing a British Sedimentological

Research Group annual meeting in the late seventies,

commented on the cyclical nature of the interest in

turbidites. Sandy turbidites were all the rage at the time,

pushed back onto the stage at BSRG by North Sea

discoveries and the studies that oil companies were asking

sedimentologists to carry out. Turbidites are back in the

international limelight for a third round at the turn of the

millennium, not the least because of the deep-water,

offshore West Africa successes in oil exploration and the

accompanying wealth of 3D data. Arnold Bouma is to be

congratulated for having stayed all three rounds so far!

Many of the more recent hydrocarbon discoveries in

turbidites, not only those from offshore West Africa, have

been in fairly muddy depositional systems. As technology

has allowed exploration further and further offshore into

ever deeper waters, the large submarine fans laid down

in front of major rivers and deltas have naturally been

an attraction for the oil business. and these systems, of

course, are on the whole muddy.

In this context, Arnold Bouma and Charles Stone,

with several people in the wings, have brought together

28 papers which were gathered to address some seven

general themes: 3-D seismic, sequence stratigraphy,

outcrop data, lithologies, logging, reservoir characteriza-

tion, experimentation. However, rather than grouping

into themes, the book presents each contribution as a

separate chapter.

Individual papers cover a reasonably broad spread: an

overview of ®ne-grained turbidite systems, a comparison

between muddy and sandy systems, present deepwater

sediment paths of Northern Gulf of Mexico, Recent

deep-sea sediment waves, subsurface studies (Neogene

offshore Nigeria, middle Miocene Gulf of Mexico),

outcrop based studies (Ouachitas of Arkansas and

Oklahoma, nine papers on Tanqua and Laingsburg of

South Africa, three papers on the West Texas Brushy

Canyon, three papers on the Jackfork of Arkansas, Mount

Messenger Fm, New Zealand), process modelling,

seismic models, borehole imaging.

In my experience, the Brushy Canyon data and the

`build, cut, ®ll, spill' model have proven to be most useful

in interpreting seismic, and comparison with several other

outcrop systems has shown the model to be highly robust.

The Brushy Canyon papers presented here tell some of

the essentials from Mike Gardner's consortium activities.

One can only applaud the use of outcrop geology (when

chosen appropriately), both for building analogues to help

interpret seismic, and to ground truth geological models.

Conversely, the wealth of ®nely detailed, high-resolution

3-D seismic, particularly from offshore West Africa, now

shows us that much outcrop geology has to be revisited

with a new generation of 3-D models in mind.

Fine-Grained Turbidite Systems will bring some of this

to the reader.

Peter HomewoodSultan Qaboos University,

Muscat, Oman

Quartz Cementation in Sandstones. Edited by

R. H. Worden and S. Morad. International Association

of Sedimentologists, 2000, Special Publication 29.

ISBN: 0 632 05482 4. Price £55.00

Quartz cementation? Why do real geologists have any

interest in that? Well, because quartz is the most common

cement in sandstones, and together with carbonate

cements, binds the grains in many clastic sedimentary

rocks that are examined at the surface. In spite of the

explosive growth since the 1970s of facies analysis,

sequence stratigraphy, and all erosional and depositional

work, the petrographic and geochemical strands of

sedimentology remain alive and well. This book witnesses

that approaches and techniques have moved far beyond

simple examination of thin sections by undergraduates,

and now include an array of integrated approaches

analogous to those deployed by organic geochemists and

basin modellers ± the difference being that sedimentol-

ogists can at least see their item of study.

The diagenetic transformation of loose sediment to

rock is, in most sandstones, assisted by quartz cementa-

tion. This common cement is also a chief cause of pore

in®lling for hydrocarbon reservoirs. About half of deeply

buried pore-space is ®lled by quartz: to put this another

way, there would be twice as much oil in sandstones

without quartz cementation. Yet despite its abundance,

the simple and pure mineralogy of quartz cement has been

one of the most dif®cult to track geochemically, and the

most dif®cult to understand the processes contributing to

its origins. This book contains publications of relevance

both to academic geologists concerned with mass transfer

and subsurface ¯uids in basins; and of interest to

industrial scientists concerned to make accurate predic-

tions of porosity. This 342-page volume is one of three

planned to be published by the IAS, as a medium for

current research articles on: quartz cements, carbonate

cements and clay cements. As we can expect from

Blackwell Scienti®c, the book is well produced, clearly

laid out, with clear diagrams and photographs. This

particular compilation grew out of a small workshop

meeting, organized in May 1996 by Richard Worden,

to focus on quartz cement. Consequently, some articles

Basin Research (2001) 13, 377±378

# 2001 Blackwell Science Ltd 377

date from that time, whereas others contain more recent

information from studies completed during the book's

4-year gestation. This was a source of frustration to some

early contributors at the time.

This book does not attempt to be a de®nitive volume

with an historical perspective. Rather it contains a

comprehensive representation of modern work available

at the time of compilation and publication. The editors

have solicited contributions from outside the original

meeting, so that the range of coverage is wide, both

geographically and in subject. There are articles reporting

on: the North Sea, offshore Norway, Egypt, Oman,

Australia, USA and Brazil. However, one tenet of studies

of deep cementation is that processes are often depth

or temperature dependent, so more important is the

coverage of subjects. This spans geochemical models

(four articles), ®ve petrographic, isotopic and geochemical

studies, three contributions examining petrophysical

and fault-structure effects, and a diverse suite of eight

case studies. The editors summarize the state of play

with their own review. There is an inevitable bias towards

studies based in hydrocarbon reservoirs. This really

re¯ects the logistical problems of sample availability from

2 to 6 km burial; the processes inferred should apply to all

quartz sands irrespective of their hydrocarbon content or

potential. Consequently, this is by nobody's standards

`just another book of oily research', but is a successful

attempt to represent the range of scienti®c approaches

deployed to understand the depositional, geological and

geochemical aspects in¯uencing the rates and volumes of

quartz cementation and pore-®lling.

So where are we now with it all? It is perhaps fair to say

that there is no ®nal consensus, there are still frontiers to

be pushed, and merits of competing processes to be

argued. Even so, undoubted progress has been made.

During the 1980s there was much discussion of deep

¯uid-¯ow, of convection, of pulses of hot water squeezed

up faults during earthquakes ... A problem with those

very geological concepts was that each sandstone unit

would need a couple of oceans worth of water gushing

through to carry its quartz cement in solution. The

situation now is viewed as considerably less dynamic.

Quartz is derived locally from grain-to-grain pressure-

solution, diffuses a few tens of millimetres, and pre-

cipitates to cement the sandstone. Fluids don't ¯ow up

faults ± in fact, some faults are much less permeable than

the surrounding rock. The major control is temperature

in the North Sea rift and Norwegian passive margin.

According to the Norwegians (Walderhaug, Lander,

Bjorkum, Bjorlykke et al.), the rate of quartz cement

growth doubles for each 10 uC of increase in classic

Arhennius fashion. It has taken us all a long time to get

back to what Heald published in 1955 ( Journal of Geology,

63, 101±114). Its rather like cool metamorphism with a

high water content. There are many advantages to this

concept of process: it's local, it's ubiquitous, and it doesn't

need two oceans worth of water for each sandstone in the

basin. So attention is now shifting to the second-order

problems: Can you quantify that process and predict

porosity (Lander and Walderhaug. Bulletin AmericanAssociation of Petroleum Geologists, 1999, 83, 433±449)?

Can you track the sources of quartz, as it can potentially

be supplied from mudrocks, sands or assorted detrital

grains? Do mudrocks and sandstones interact chemically

during deep burial? How cool can quartz grow? How do

¯uid pressure and effective grain-to-grain stress interact?

Can we ®nd anomalous places where the general model

does not work or needs to be modi®ed ± it seems that

clay coatings around detrital grains block cementation,

and microcrystalline quartz coatings might achieve the

same result, as might oil-®lling of the pores. These are

important for the hydrocarbons industry ± as predictors

of unusually large pore volumes in locations controlled by

depositional facies, or by structure. To make progress

with all these questions will need, inevitably, more data.

The ultimate goal is a predictive computational model,

linked into the basin evolution. Personally, I doubt that

will ever be feasible ± there are too many geologically

poorly quanti®ed unknowns. But it will be fun getting

towards it.

This is an excellent compliation, but still a book to

recommend selectively: sequence stratigraphers, basin

modellers and petrographers don't overlap very much.

Anybody working with burial cements or porosity should

browse it; clastic petrographers should buy their own

copy. All respectable geo-libraries should have access to

this realistically priced volume, which will remain useful

for several years into the future.

R. Stuart HaszeldineDepartment of Geology and Geophysics,

University of Edinburgh,Edinburgh EH9 3JW, UK

E-mail: s.haszeldine@glg.ed.ac.uk

Book reviews

378 # 2001 Blackwell Science Ltd, Basin Research, 13, 377±378