Restless Tides of Time: Sea-level Change—Past, Present and Prescient
If readers will forgive the pun, eustasy—the study of global sea-level change—has had its ups and downs in geoscientific thinking, particularly in recent decades. The concept was introduced in the late nineteenth century by the Austrian geologist Eduard Suess, but it came to prominence in the late twentieth century through the work of a group of Exxon researchers led by Peter Vail. Bilal Haq, the author of this book, was for part of his career a member of that research team, and his publications over the past forty years have been central to debates on eustasy. A 1987 paper led by Haq on Mesozoic and Cenozoic eustasy is among the most referenced works in sedimentary geology and stratigraphy and remains the de facto framework for understanding eustatic change. It is therefore timely that this volume conveniently synthesises Haq’s work, and that of his collaborators, on sea-level change.
Restless Tides of Time provides a clear and readable overview of the methods used by Haq to identify sea-level change in the rock record, alongside summaries of his published interpretations of eustasy across the major Phanerozoic epochs. Possible driving mechanisms and biotic responses to eustatic change are outlined, and the discussion extends to anthropogenic sea-level rise and future trajectories. These latter—and often emotionally charged—topics are presented from a firmly scientific perspective, to positive effect.
The heyday of eustasy research lay in the 1980s and 1990s, when academic researchers embraced global sea-level curves as a framework for interpreting stratigraphic sections, and petroleum geologists recognised their predictive value for sequence stratigraphy in the subsurface. Over the past two decades, however, interest in eustasy has declined. Extracting a robust global sea-level signal from the rock record has proved challenging, the synchroneity of events is difficult to demonstrate, and successive iterations of the “Haq curves” have not always matched observations in terms of timing, rate, or magnitude. Critics have also highlighted the limited documentation of the data underpinning these curves and questioned some of the proposed driving mechanisms. As a result, eustasy has become sufficiently unfashionable that more recent stratigraphy textbooks do not mention the subject at all.
These critiques of Haq’s work are, perhaps unsurprisingly, absent from the present volume. Readers should therefore recognise that while the book offers a valuable and authoritative summary of a particular approach to the study of eustasy, the interpretations presented remain open to debate and comparison with alternative eustatic models.
Reviewed by Mike Simmons
DETAILS
BY: Bilal Haq (2026) Springer Cham, 198 pp.
ISBN: 9783032102911
PRICE: £22.99, springer.com
