Exploration Insights November 2019 | Page 12

12 | Halliburton Landmark
New Product: Basin-Scale
Frameworks
Exploration Insights | 13
Adding Context to
Oceanic Anoxic Events
as Source Rock Drivers:
A New Approach for
Frontier Areas
by: Christine Yallup and Benjamin Gréselle
OAE II at the Halle Hesseltal section in northern Germany. Photograph provided by and used with the permission of Prof. Joerg Mutterlose, University of
Bochum.
Our basin-scale frameworks bring together disparate data from the public
domain to generate depth surfaces that can be used to better assess
hydrocarbon prospectivity. This new product provides:
» High resolution models, which give you the ability to analyze the subsurface
during the reconnaissance stages of exploration on a basin-scale
» Enhanced subsurface resolution, and the context beyond your area of data
control
» Generated depth surfaces that can help you to better assess the
prospectivity of key petroleum elements
These new basin-scale frameworks are available within the Depth Analysis
Openworks project backups, as ArcGIS grids or ZMap format for Neftex ®
Insights Advanced subscribers.
Contact us today for more information.
THE IMPORTANCE OF SOURCE
ROCK PREDICTION
Recent analysis suggests that almost half of
exploration wells that fail to find commercial
quantities of hydrocarbons do so due to issues
with the prediction of a viable source rock
system (Rudolph and Goulding, 2017). Of these
issues, the most common reason for these
failures was erroneous estimation of source rock
presence (Figure 1). It is, therefore, important
that we improve our understanding of source
rock distribution. Can we challenge commonly
held assumptions about drivers of source rock
deposition to reduce the risk of wells failing due to
lack of source rock presence?
It has long been noted that strata favorable for
the production of hydrocarbons are not evenly
distributed throughout geological time (Figure 2;
Klemme and Ulmishek, 1991). The Eocene, mid-
Cretaceous, Late Jurassic, Late Devonian, and
Silurian are particularly remarkable in terms of the
quantities of proven hydrocarbons attributed to
source rocks of these ages. These source rocks
have often been linked to oceanic anoxic events
(OAEs). These events, in which large portions
of the ocean floor appear to have become
anoxic, correspond to short-lived, strong
perturbations of the carbon cycle, with oceanic to
global extent. They are commonly characterized in
the stratigraphic record by widespread deposition of
organic-rich strata. This has led to the assumption
that OAEs drove widespread organic enrichment,
and the deposition of prolific source rocks.
How valid is this assumption? To test this,
44 wells from the Neftex ® Insights dataset
were studied, covering a wide range of
paleogeographic and environmental settings.
These were used to quantify the impact of OAE2
on organic carbon burial, by studying well-time-
constrained total organic carbon (TOC) data.
2018 Frontier Well Failure Analysis
N=76
Reservoir
Presence
Updip Seal
Reservoir
Quality
Trap Size
Carbon
Dioxide
Uneconomic
Phase
Focusing your exploration efforts
0 1
© 2
Timing/Migration
9 H
a l l
u
i b
Source
Presence
Source Maturity
Migration
Figure 1> Analysis of reasons why wells failed to find
commerical quantities of hydrocarbons in 2018. Data compiled
from public domain well reports published in 2018.