oa High Resolution Logs of Organic Carbon by LIPS (Laser Induced Pyrolysis System)

Characterizing the content and understanding the distribution of organic carbon in sediments is a key element for the exploration and the production of new or revisited petroleum prospects.

Developed by Total, the LIPS has a set of unique features:

∘ it is poorly destructive: indeed, the laser impact affects only 1 mm³ of material,

∘ it generates very large datasets / big data (typically 10,000 data points and more for 100 meters of core). Statistical treatment on such data sets provide more significant and more representative description than discrete and low resolution sampling. This opens completely new perspectives to understand organic matter deposition and distribution. Thus, descriptive and inductive statistics may be used to infer laws and to detect:

  - trends, behaviors and dependencies,

  - relationships with lithology, rock type, Milankowitch cycles …

∘ it provides high resolution data allowing more accurate location and a better quantitative evaluation of the organic carbon in cores.

The LIPS equipment currently installed in Doha (Fig. 1) addresses typical issues in the Middle East.

Figure 1: LIPS equipment installed in TRC-Q, Doha, Qatar

The high resolution data acquisition allows exhaustive location of permeability barriers in carbonate reservoirs also known by petroleum engineers as tar mats. It also contributes to the identification of all the sweet spots in source rocks layers for non conventional plays in exploration and development. As such it is a tool contributing significantly to the economical exploitation of shales gases and shale oils.

“Milanković-type“ climate cycles are due to variation of Earth rotation. They are known to control fluctuation of sedimentary organic carbon. The data presented in Fig. 2 indicate that the resolution of LIPS data is high enough to highlight the climate change induced variations of organic carbon in the Jordan oil shale play. It also shows the added value of the LIPS in comparison with the conventional Rock Eval data.

Figure 2: High resolution LIPS data (1/cm) highlights the climate induced variations of organic carbon in the Jordan oil shale

In light of successful results obtained for GCC issues, new developments involving local staff are expected in Doha with the support of Total's Headquarter. Indeed, specific applications to carbonate reservoirs and resources are underway, for instance:

∘ new methods for performing quantitative analysis of bitumen forming tarmat in carbonate reservoirs. Middle East is the ideal trial field, since all tarmat configurations and formation pathways exist in these countries,

∘ new and simple devices for specific compound detection (e.g. CO2, organo-sulfur compounds...). The goal is to make a distinction between fossil organic carbon, tarmat, heavy oil and oil. Automatic measurement High resolution correlation between TOC and of residual permeability may be performed,

∘ hyphenated techniques from the coupling of the LIPS with on-line spectroscopic detection technologies (e.g. isotope ratios mass spectrometer).

The LIPS is a real breakthrough in terms of both its technological originality and its unique ability to characterize carbon deposits.