Archive

Past lectures

lecture

lecture

Wednesday 21 December 2016  17:00 - 22:00

2016 XMAS Lecture: The E&P Business; Steering between Scylla and Charybdis

Lecturer: Evert van de Graaff (VDG)

Abstract:

Read more...

In Greek mythology [e.g. Homer’s Odysseus] Scylla and Charybdis were major hazards to sailors that wanted to pass through the Strait of Messina. Scylla was a six-headed monster that threatened to devour the sailors on board a ship, whereas Charybdis was a whirlpool that could cause the loss of the entire ship. For the EP business I use Scylla and Charybdis as metaphors for respectively ‘paralysis by analysis’ and ‘the 80% solution will do fine’. EP projects are typically manpower and capital intensive, high risk / high reward projects. To ensure commercial success it is critical to strike a proper balance between ‘paralysis by analysis’ through overly detailed studies, and the cutting of corners by assuming that ‘the 80% solution will do fine’. To achieve this balance it is essential to understand the technical, economical, commercial, organisational and political risks that can cause an EP project to de-rail. Based on a number of well-known and not so well-known examples [e.g. Cormorant Block IV / Chinguetti / Ekofisk / Kashagan / Sakhalin / Macondo] the consequences of not understanding and/or ignoring key risks are highlighted. In hindsight those risks though either not recognised or acted on at the time, were rather obvious and disaster could have been easily avoided. It is hoped that awareness of these ‘learning points’ will help members of the PGK to successfully ‘steer between Scylla and Charybdis’ in their own EP projects. If nothing else, hearing about some juicy case stories should help to put you in the proper mood for the Festive Season in these times of Industrial gloom and doom.

Location

KIVI Building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Wednesday 16 November 2016  17:00

Monthly Lecture: Better Geophysics for De-Gassing Shallow Hazards (or De-Risking Shallow Gas)

Lecturer: Andrew Cochran (HALO)

Abstract:

Read more...

Shallow Gas remains an attractive resource to exploit near ageing infrastructure on the Dutch Continental Shelf; Quads A&B have proven the commerciality of such a resource and addressed with effective resolution of production issues associated with these young, unconsolidated reservoirs.
However, going forward the legacy seismic data base may not be ideal for continued exploration of these young reservoirs. Recent large towed-array 3D seismic acquisition lacks near surface sampling (i.e. minimum offset can be as much as 550m) and the source is tuned for deeper objectives.
Legacy 2D seismic is actually better to map these Miocene objectives due to regularity of offset distribution, better spatial sampling and a source better tuned toward shallower objectives. These legacy 2D then offer better support for attribute analyses such as Amplitude Variations with Offset.
Frequency content in the shallow targets can be 30-35Hz and has been sampled to 4ms and processed with 12.5x25m bins. This means that much of the resolutions desired is beyond the existing seismic tuning. Shorter sample rates and smaller bins may preserve wider bandwidth.
Going forward, new 3D seismic may be required but acquired with specific parameters to support the Shallow Objectives. Hopefully, better tuned and sampled data will also support inversion and better reservoir characterization and development planning through horizontal wells.
Some survey design considerations would be towing shorter cable, reduced record lengths, higher temporal sampling, regularized offsets and smaller bin-sizes. The cost of the smaller bins in processing would be offset by reduced record length and fewer traces.

Location

KIVI Building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Wednesday 19 October 2016  17:00 - 19:00

Getting the most out of drill cuttings Application of automated mineralogy and nanoindentation techniques

Lecturer: Merijn de Block (SGS)

Abstract:

Read more...

During drilling operations, drill cuttings are examined at the well site to determine the lithology and stratigraphy of the drilled formations. After examination they are usually stored in a shed and never looked at again. This is a shame as drill cuttings can provide valuable information on key rock properties by utilizing innovative analytical methods, which is especially useful in cases where cores are not available and the log data are limited. In this talk, two of these analytical methods are presented, i.e. automated mineralogy solutions and nanoindentation.

Automated mineralogy solutions (such as QEMSCAN) combine electron microscopy with x-ray spectroscopy for quantitative analysis of the mineralogy and lithology of rock samples. As these solutions are non-destructive the textures of the rock samples are preserved, providing textural analysis and mineralogical mapping of the rock samples.

Nanoindentation is a method to determine the mechanical properties of small samples by pressing a hard tip with known mechanical properties into a sample and simultaneously measuring the applied load on the tip and the displacement of the tip into the sample. From the ratio between the applied load and the displacement selected mechanical properties are determined, including the Young’s modulus and the hardness.

The application of these analytical methods to oil and gas projects is demonstrated using several case studies. In these studies drill cuttings analysis results were used for different purposes, including the delineation of lithostratigraphic zones and well correlation, the development of sedimentological concepts for exploration, and the evaluation of formation fracability for identification of sweet spots in unconventional reservoirs.

Location

KIVI Building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Wednesday 14 September 2016  17:00 - 19:00

Monthly Lecture: Fluvial fans and megafans: modern evidence and geologic models (or: what really infills continental basins)

Lecturer: Dario Ventra

Abstract:

Read more...

Fluvial fans and megafans have been recently reevaluated for their relevance to sediment distribution within modern continental basins, and may have contributed to the aggradation of thick alluvial successions forming a large fraction (if not the majority) of non-marine stratigraphic records. An increasing body of research on active fans worldwide is illustrating common processes and dynamics from channel to system scale, while highlighting differences related to specific climatic settings, and interactions with surrounding sedimentary environments. At the same time, studies on the geology of ancient (Proterozoic to Plio-Quaternary) fan deposits show that long-term progradation of these systems produces consistent architectural signatures and trends, such as vertical stacking of laterally extensive, tabular units of amalgamated channel fills and overbank fines with minimal erosional discontinuities, poorly developed pedogenic horizons, and regionally predictable, proximal-to-distal fining of coarser facies associations and reduction in the volume, dimension and connectivity of channel fills. Fluvial deposits are among the hardest to tackle for hydrocarbon and groundwater development, due to their hierarchical heterogeneity and especially to difficult assessment of palaeohydrologic and process trends on regional scales. The predictable spatial organization of facies associations and trends in fluvial-fan successions, confirmed by numerous examples, suggests that depositional models for thick alluvial units in the subsurface should include possible accumulation in fan settings, improving success from preliminary basin exploration to more advanced phases of reservoir characterization and production.

Dario Ventra - TNO

TNO (Petroleum Geoscience), Utrecht, Netherlands
& Department of Earth Sciences, University of Geneva, Switzerland

Location

KIVI Building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Monday 13 June 2016  17:00 - 22:00

PGK-SPE Annual BBQ 2016

ABSTRACTS:

Read more...

High-resolution stratigraphic correlation of Rotliegend fluvial fan deposits and its relevance to exploration and production

Mat De Jong and colleagues - ENGIE E&P Nederland B.V.

Oh no, not again! Not again the Rotliegend! You may be inclined to think that, after more than fifty years of exploration and production, there are no secrets anymore in the Upper Rotliegend sediments of the Dutch part of the Southern Permian Basin. Is there nothing new to be learned ‘after SEPM Special Publication No.98’? Application of high-resolution log-based correlation techniques integrated with outcrop-based information on the depositional processes of thin-bedded fluvial fan sediments, however, produces a remarkably detailed chronostratigraphic framework and an improved understanding of the spatial and temporal distribution of reservoir facies – to the benefit of both exploration and production.

The lithostratigraphic units of the RGD & NOGEPA nomenclature of the Upper Rotliegend are generally accepted to be diachronous, leading to much confusion when used in correlating at field and regional scale. Sequence stratigraphic concepts are now being applied, which rely on the identification of (maximum) flooding or wettening surfaces as the correlatable, near-synchronous, events. In a similar approach, we have used conventional and unconventional correlation techniques to identify equivalent, near-synchronous, vertical lithofacies changes in the sand-poor and evaporite-bearing section of the central part of the basin – where we can expect the most complete preservation - and extended the correlations to the south, to the area where the sand content increases as well as the likelihood of erosional events and, therefore, hiatuses. The vertical resolution is generally in the order of 5-10 meters and occasionally higher. The correlation is underpinned by a thorough understanding of the fluvial fan depositional environment, and is in line with and benefitted from the work on thin-bedded crevasse-splay deposits in the Altiplano Basin of Bolivia and the Ebro Basin of Spain by
Donselaar and colleagues (Monthly PGK Lecture, November 2015).

The current approach gives better insight into the processes of filling the basin and its architecture. Among other things, the work has revealed the existence of a topography at the Base Permian Unconformity surface, which controlled the fluvial fan development; it shows a shift of the depositional axis of the fluvial fan through time; it offers a predictive model for the occurrence of sands at field and regional scale; and, it reduces risks involved in drilling highly deviated and costly wells.

What better subject could reservoir geologists and engineers learn than the language of well testing derivatives?

Patrick Corbett

Well test data – or more specifically pressure build-up data and the derived derivative response are scrawl of dots on a graph with meaningless axes to most geologists. However, they should be considered as the language of the nearby geology speaks to the well bore. For some it is merely noise and for some signal. Those that can decipher the language will find it is a rich source of information.

Often non-unique, the response are poorly constrained by other hard engineering data. So the engineers who hear the signal and recognise the language and, whilst understanding the words, might not grasp the full meaning and become confused.

This is the paradox of reservoir characterisation. The reservoir speaks in a language that geologists don’t traditionally understand. However, this language can be learned as the message can be a critical one!

This talk sheds light on the words that make up this language (the vocabulary), looks at some simple combinations of words (sentences) and give insights into some of the stories that can be teased out of the well test data. We explore a mixture of synthetic well test simulation studies where geological models are converted into the pressure derivative language and case studies where the pressure derivative response is converted into a geological story. Hopefully, the audience will take away an appreciation of the language and be inspired to devote more time to learning this modern universal reservoir language of the reservoir geoengineer.

lecture

lecture

Wednesday 18 May 2016  17:00 - 19:00

Monthly Lecture: Two PhD student lectures

Lecturer: Helena van de Vegt / TU Delft IBA Team

Abstracts:

Read more...

Generating and applying synthetic reservoir analogues
by Helena van de Vegt

Both ancient and modern reservoir analogues are used to improve the estimation of geobody dimensions and connectivity within a reservoir. However, finding an appropriate analogue can be challenging. Even the most appropriate analogues typically only match a subset of the unique conditions comprising the reservoir’s depositional environment. To simplify analogue identification, libraries of data from many different sites are often consulted. However, data is limited to accessible outcrops and available data from modern systems. To supplement these sources, a library of synthetic realisations can be generated and accessed as required, based on any combinations of boundary conditions.

Our current work simulates deposition in river delta environments, calculating the hydrodynamic, sediment transport and morphological responses to a range of boundary conditions. Studying depositional behaviour through process-based models has two important advantages. Firstly it allows the investigation of individual variables independently from each other. Secondly the output data has a high spatial and temporal resolution. To illustrate the application of these synthetic delta deposits, we present a set of tools to quantify the variability within one such a model ensemble.

In addition to the ongoing research into deltaic deposition, TUDelft, Deltares and Statoil are collaborating to develop a new software tool allowing users to build, access and analyse a large database of synthetic delta analogues.

The hydrocarbon potential of the Taranaki Basin, New Zealand
by TU Delft IBA team: Duaa Alshiroofi, Thore Boerboom, Lisanne Douma, Axel Sandén, Fu Kai Yap

This year, a team of five MSc/PhD students of Delft University of Technology won the AAPG Imperial Barrel Award for the European Region in Prague. During a period of eight weeks, the team members analysed a dataset (e.g. geology, geophysics, petrophysics, production infrastructure) of New Zealand’s Taranaki Basin. On June 17 the team will present their findings to a panel of industry experts during the world finals in Calgary.

New Zealand’s Taranaki Basin is a Cretaceous to Tertiary sedimentary basin that evolved during phases of rifting in a continental margin environment, followed by a phase of post-rift passive margin subsidence. This continued up to the present day in a transpressional regime that resulted in uplift and erosion. So far, only the Taranaki peninsula and shallow marine part of the Taranaki Basin have demonstrated to result in commercial hydrocarbon accumulations. This project defines potential petroleum systems in both the shallow and the deep water parts of the Taranaki Basin. The syn-rift to early post-rift phase of basin history contains characteristic petroleum system types, based on terrestrial to marginal- and deeper marine deltaic source- and reservoir rocks. The shallow marine petroleum system types are used to predict the petroleum prospectivity of the deep water Taranaki basin.

Location

KIVI Building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Wednesday 20 April 2016  17:00 - 19:00

Monthly lecture: Westphalian A: The hidden pearl of the Dutch sector of the North Sea? by Paul Segers

Lecturer: Paul Segers

Abstract:

Read more...

The gas industry in the Netherlands has flourished for over 50 years. Many gas fields in the off shore, smaller and larger, have been discovered and developed making the off shore Netherlands with its different plays a mature to very mature petroleum province. This leads to explore for new and under developed plays which can hold a significant amount of hydrocarbons in place. The Carboniferous Westphalian A got the potential to be the rather new play to be developed in order to stretch the tail-end production of the existing off shore installations.
In the Dutch sector of the North Sea one field in producing from the Westhalian A as well as a handful fields in the UK sector close to the K-Quadrant of the Dutch sector of the North Sea. The Westphalian A consists of fluvio-deltaic deposits resulting from a Southward progradating delta. These sand-shale intervals can be linked to a sequence stratigraphy model which is alternative option the classic Exxon sequence stratigraphic model to predict the sand intervals. Linked to this conceptual model the interval and lateral extend of where coals are formed will be discussed as well, that not only influence the sourcing, but also the development of the field by horizontal wells.
As an analogue some of the UK fields will be discussed to illustrate the effect of the depostional environment on the reservoir quality. These fields might also be used to develop these sort of fluvial-deltaic reservoirs in near future.
Is the reservoir quality in the other K and L blocks sufficient to be an interesting hydrocarbon play and moreover, how to develop this Carboniferous play? In this presentation the sequence stratigraphy model of the Westphalian A, the coal deposition and the potential development of these Westphalian prospects will be discussed.

Location

KIVI building
Prinsessegracht 23
2514 AP
Den Haag
View map


View larger map

lecture

lecture

Wednesday 23 March 2016  17:00

Zuidwal: Has all the gas been produced and is it time to close in?

Lecturer: Chris Maaijwee

Abstract:

Read more...

The Zuidwal field was discovered in 1970, but due to its location in the Wadden Sea has only come on stream 18 years later. Zuidwal is now nearing end-of-field life. EBN, as part of their commitment to optimize the value of oil and gas resources has spearheaded a review of the field potential. An update of the petrophysical analysis had already been carried out in 2012. This presentation will focus on the work carried out in 2015, which includes seismic interpretation and velocity modelling and will also include a short discussion on the geological history.
The field is largely covered by a 3D seismic survey and has a relative abundance of well velocity data. A Gas Water Contact can be interpreted and a clear outline of the GWC seismic anomaly can be extracted. Despite this a longstanding discrepancy has existed between the GIIP calculated in the static models and the GIIP calculated to be connected to the wells. In a renewed effort to close this ‘GIIP Gap’, the available seismic and well data was thoroughly reviewed, interpreted and a new static model was built. The structural uncertainty was significantly reduced with an updated mis-tie analysis (of 2D and 3D seismic data), by conditioning the time-depth conversion to the GWC seismic signal and by including the effects of Late Cretaceous inversion.