How the search for oil solved the enigma of flowering plants

The rapid appearance of flowering plants 125 million years ago during the Early Cretaceous has been an evolutionary mystery since Darwin’s time.

The diversity of ancient pollen in the rock formations of the Arabian Peninsula that might significantly contribute to the solving of this mystery was found by Aramco geologists, together with researchers from University of Western Australia — shedding new light on a puzzle that has intrigued scientists for centuries.

Geological expertise is in Aramco’s DNA.

It was Max Steineke, who became the company’s chief geologist in 1936, that famously encouraged his team to “drill a little deeper” at Dammam Well No. 7 in 1938, bringing in the first viable oil well in Saudi Arabia and laying the foundation for success at Aramco.

Understanding the subsurface is an element in the success of the hydrocarbon industry.

The expertise of our geological specialists remains equally important in our Upstream business today, playing a role at every stage, from pre-discovery to well placement and, ultimately, production.

A key component of our geological analysis is palynology — the study of pollen, spores and other organic-walled microfossils extracted from rock cuttings.

Analyzing these fossils helps us image and map the distribution of the subsurface rock successions, allowing petroleum geologists to identify potential reservoirs.

This ultimately leads to the discovery of new hydrocarbon fields or improves the development strategies of existing fields.

Palynology is now also being applied in studies related to carbon-storage initiatives, geothermal and mineral exploration, and has even contributed to the broader scientific understanding of the evolution of life on Earth.

Uncovering the mysteries of the past

Aramco geologist Dr. Hani Boukhamsin carried out a palynological study of rock formations in the Arabian Peninsula as part of his PhD research at the University of Western Australia.

This study has offered potential insights into one of the long-standing paradoxes in Charles Darwin’s theory of evolution.

A key aspect of Darwin’s theory is that evolution is a gradual process, occurring over an extended period of time.

However, the sudden and rapid evolution of flowering plants during the Early Cretaceous epoch, around 125 million years ago, posed a challenge to this concept.

Darwin himself referred to it as “the abominable mystery”. Despite ongoing research, the underlying reasons for this rapid evolution have remained elusive.

Recent research by Dr. Boukhamsin, published in the Earth-Science Reviews journal, has shed new light on this enigma.

His study analyzed pollen samples extracted from the Biyadh and Shu’aiba formations in Saudi Arabia, which date back to the Early Cretaceous epoch.

The results revealed an exceptionally diverse range of flowering plant pollen, surpassing the diversity found in contemporaneous records from Europe and North America.

This discovery suggests that the Arabian region may have played a role in the early evolution and diversification of flowering plants.

This finding led him to propose that the islands and archipelagos situated off the Arabian Plate were the cradle of the speciation of flowering plants.

During the Early Cretaceous epoch, the Arabian Plate experienced a warm climate with seasonal rainfall, giving rise to numerous rivers that flowed into the ocean and formed extensive deltas, depositing thick sand successions.

This process not only led to the deposition of the country’s hydrocarbon reservoirs, but also resulted in the creation of a vast Arabian forest.

His first model proposed that during periods of sea-level drop, migratory birds and flying reptiles served as key vectors for dispersing flowering plant seeds between islands in the region.

As sea levels subsequently rose, these islands would be isolated, and this isolation played a role in the speciation and diversification of the flowering plants, giving rise to unique ecosystems similar to those found in the Hawaiian archipelago.

The second model posits that the lakes and other bodies of water along the Arabian coast created isolated environments that facilitated the evolution of aquatic flowering plants, ultimately leading to their isolation, speciation, and diversification.

Looking to the future

Integrating knowledge derived from palynology with insights from other geological and geophysical disciplines has yielded several practical applications over the years.

The incorporation of digital tools and artificial intelligence into our workflow has the potential to enhance our understanding of the subsurface.

Our digital transformation team is diligently converting a vast amount of data from legacy paper reports as well as palynological slide collections, dating back to the era of Max Steineke, into digital formats that can be leveraged to inform AI systems.

We also envision potential in training AI in various domains, such as a rapid integration of vast geological datasets to reconstruct a more comprehensive and accurate picture of the subsurface geology.

By doing so, AI can help us bridge the knowledge gaps in our understanding of the subsurface, ultimately leading to more precise predictions and better-informed decision-making.

However, it’s essential to note that the expertise of our geoscientists remains our most valuable asset, even if AI augments our capabilities and helps us work more efficiently, reducing project timelines.

As our work in palynology demonstrates, advancing our understanding of the subsurface not only supports Aramco’s energy exploration efforts but also contributes to the broader scientific community’s understanding of the Earth’s history, evolution, and the complex interplay between geology, climate, and the natural world.