Daniel Mikes

This is Python code (SamSim) for simulating and analysing data related to insolation and sampling. The code uses various functions and parameters to create time series data, perform simulations, and analyse results. Below, we describe main components and how to use SamSim. GitHub: https://github.com/danmikes/samsim CoLab: https://colab.research.g...

Sequo-Strat (Sequence Stratigraphy) is a method that has many applications, the essence of which seems to be: (1) correlate depo-units (deposition units) to depo-units and (2) correlate depo-units to sea-level. These build respectively on following premises: (1) depo-units are laterally continuous and (2) depo-units are sufficiently frequent. For t...

In a cohesive team everything seems to function effortlessly and there is no need to analyse why and how it works so well. In a dispersive team everything functions with great effort and there is need to analyse why and how it works so badly. General approach is to search for flaws in current team and attempt to fix them. We suggest an alternative...

Can one infer a signal from discrete samples? The general answer to this question is: (1) Yes, if one knows signal shape and sample times; (2) No, if one ignores any of those. If one applies the question to infer sea level curve in time domain from shoreline trajectory in space domain the general answer is: (1) Yes, if one knows signal shape of all...

Deposition events are instantaneous and separated by varying periods of stasis; they therefore have finite thickness in space domain, yet negligible duration in time domain. Depo events form a stack of layers in space domain and a sequence of separated events in time domain. This discrepancy jeopardises correlation in space domain, e.g. shoreline t...

We analyse a crust-scale 3D structural model of the Western Bredasdorp Basin (WBB) located offshore southern South Africa to assess both the spatial and temporal development of geothermal gradients in the Southern African ‘passive-transform’ continental margin. The results of simulations of the present-day conductive thermal field were used to cons...

Education is a complex social construct by which teacher ideally optimises learner's learning process. The construct is similar at every level of education, yet social interaction varies. And it is therefore social interaction that plays a vital role in the education process. Yet, in today's world the social element is all too often neglected and e...

Particles settle with a terminal velocity proportional to their grain size squared when freely falling through fluid. Silt sized particles should therefore fall significantly faster than clay sized particles. In practise they don't, because they coagulate to form aggregates-flocs-of silt size, which fall at similar velocity as their single particle...

The English language appears easy to communicate in, because it possesses quite a flexible discourse and a relatively small vocabulary compared to many other languages. However, discourse and vocabulary in every country is different and in order to be accepted one must adopt it. When submitting an academic article to an international journal one is...

Depositional events at the shoreline can be considered non-uniformly spaced samples of (relative) sea level; the shoreline trajectory constructed from shoreline positions in a cross-section through a delta can therefore be considered a proxy to the sea level curve. The problem is that depositional events are stacked on top of each other in the spac...

The Nelson Mandela Metropolitan University (MU) carries the name of arguably South Africa's most famous icon, one who has become synonym of man's ultimate virtues of integrity and ubuntu. Integrity is more widely used and can be considered a balance of thought and action of the person. Ubuntu is used on the African continent and can be considered a...

Modern developments in “Complex System Science” and its geoscience equivalent “Earth System Science” require a certain skill set from the academic graduate in order for one to be fully applicable to the modern professional environment, be it academia or industry. It seems that academic curricula are not fully adapted yet to this shift and as a resu...

This manuscript addresses the gap that exists between modern geoscience and geology, which is caused by the relative isolation in which mainstream geologists have operated and continue to operate. This gap is inevitable, but could be significantly reduced by adopting frontline developments in “Complex System Science” and its geoscience equivalent “...

Palaeo shoreline is a commonly used proxy for palaeo sea-level, but only if deposition is continuous and constant will shoreline trajectory T(l) completely capture sea-level time-series E(t). Artificial deltas were generated in the Eurotank flume facility under stepwise tectonic subsidence, periodic sea-level fluctuation and two periodic water-disc...

Present day geology is mostly empirical of nature. I claim that geology is by nature complex and that the empirical approach is bound to fail. Let's consider the input to be the set of ambient conditions and the output to be the sedimentary rock record. I claim that the output can only be deduced from the input if the relation from input to output...

I prepared this document to present as HDR, but never did.

The southern South African continental margin documents a complex margin system that has undergone both continental rifting and transform processes in a manner that its present-day architecture and geodynamic evolution can only be better understood through the application of a multidisciplinary and multi-scale geo-modelling procedure. In this study...

Comprehensive Karoo chronostratic study

Investigator 1. Daniel MIKES (DM)-geology-sedimentology-recent deposystem 2. Richard BERRY (PhD) (RB)-geology-programming-geostatical analysis 3. Johan ten VEEN (JV)-geology-sedimentology-ancient deposystem 4. Ron STEEL (RS)-geology-sedimen-tology-ancient deposystem 5. John TIPPER (JT)-geology-sedimentology-digital simulation 6. ? (?)-engineering-c...

We propose a workflow to obtain shoreline length-series from artificial deltas and to transform them into shoreline time-series by way of a simple yet effective method that can be applied on any existing artificial delta created in a laboratory flume-tank. The workflow is based on first principles and is therefore guaranteed success. With the resul...

Sequence-stratigraphic models for fourth to sixth order, glacio-eustatic sequences based only on relative sea-level variations result in simplified and potentially false interpretations. Glacio-eustatic sea-level variations form only one aspect of cyclic climate variation; other aspects, such as variations in fluvial water discharge, vegetation cov...

Sequence-stratigraphic models for 5th to 6th order, glacio-eustatic sequences based only on relative sea-level variations result in simplified and potentially false interpretations. Glacio-eustatic sea-level variations form only one aspect of cyclic climate variation; other aspects of climate variation (e.g. variations in river runoff) can lead to...

Geology has evolved from a descriptive science into an empirical science. There exist numerous empirical methods to describe the rock record by means of geometrical and qualitative analysis. There exist also numerous mathematical methods to describe the rock record by means of physical and analytical equations. It is argued that there is a gap betw...

In recent years, construction of 3D geological models and their subsequent upscaling for reservoir simulation has become an important tool within the oil industry for managing hydrocarbon reservoirs and increasing recovery rate. Incorporating petroleum system elements (i.e. source, reservoir and trap) into these models is a relatively new concept t...

Basin subsidence analysis, employing the backstripping method, indicates that two fundamentally different basin-generating mechanisms controlled the Tanqua depocentre development in the southwestern Karoo Basin, South Africa. On one hand, the subsidence curves display initial dominantly decelerating subsidence suggesting an extensional regime and t...

In recent years, the construction of accurate geological models and subsequent upscaling for reservoir simulation are commonly built from an integration of subsurface and surface datasets. Surface data can supply additional information on facies variability and small scale heterogeneity needed for a robust reservoir model, yet impossible to attain...

Natural flocs in an estuary grow with increasing time, salinity, suspended particulate matter concentration, and with decreasing turbulence. Although various theoretical and empirical functions for floc growth have been proposed in the literature, they are all complex. It is argued in this study that there should be a simple and general function of...

We conducted an experiment with 10 karate students consisting of a range of experience levels, ranging from junior to senior and all intermediate levels. At the start the white belt was slowest and the black belt fastest and all others in between. At the end of the experiment all were equally fast and faster than the black belt at the start. This r...

Cohesive suspended particles in a river aggregate into microflocs with average diameters of 10-20 mu m, which on their arrival in the estuary aggregate to macroflocs with average diameters of 100-200 mu m. We performed a laboratory study on samples from the Seine estuary. The experiments show a more or less systematic behavior of floc size with dri...

Poster

Lack of age dates in the terrigenous Cenozoic sediments of the Duero and the Ebro sedimentary basins has complicated tecto-stratic correlation across the two basins. We tentatively synthesize a range of existing studies and new data to construct a rough general paleogeography throughout Upper Cenozoic times. The more extensive erosion of the Ebro h...

Deltaic successions are an important habitat for some of the major world's fossil fuel reserves (i.e. oil, gas and coal). An outcrop analogue study of the excellently exposed Permian siliciclastic Kookfontein deltaic sequence will therefore improve prediction of sandbody geometries and complex internal heterogeneities of subsurface examples. Prelim...

A deltaic sedimentary system has a point source; sediment is carried over the delta plain by distributary channels away from the point source and deposited at the delta front by distributary mouth bars. The established methods to describe such a sedimentary system are "bedding analysis", "facies analysis", and "basin analysis". We shall call the am...

The power of logic.

In this work I use the numerical model TAO to study the evolution of the Bureba escarpment, sitting at the watershed between Duero and Ebro Basins and draining into the Rioja Trough. Facies correlation across this area is troublesome through lack of age-dates and therefore timing of tectonosedimentary events is controversial. Numerical modelling sh...

Sequence stratigraphy' claims to be a method that describes the 3D/4D basin-fill. However, it comes short in a number of ways: there is no concensus on its concepts and terminology, some of the assumptions are known to be incorrect, there is no general model that fits all environments and locations. The scientific community has been working hard on...

This is a response to the main author of (Catuneanu et al., 2009).

Artificial miniature delta in Eurotank

Artificial miniature delta in Eurotank

The construction of reservoir models is frustrated by the fact that core and well cover only a fraction of the reservoir volume and it is therefore difficult to determine features like facies shape, -size, and -distribution, inter- and intra-facies boundaries and lateral trends from them. These features are, however, critical to fluid flow and they...

Small-scale heterogeneities like crossbedding hamper fluid flow and cause oil to be capillary trapped at the intersections of coarser to finer lamina. These effects are fairly well established, but less well established is the method to construct an adequate flow cell model containing critical hydraulic properties like bed-shape and -size, lamina-s...

The effect of small-scale heterogeneities on fluid flow through a reservoir is determined using one of so called mathematical upscaling methods, that as such are fairly well established. Less well established, however, are the operations that provide their input, i.e. construction of reservoir model and acquisition of data. We thereto propose syste...

Sampling permeability from individual laminae in crossbedded rocks is very well possible by making use of a so-called probe permeameter. The methodology and calculation of permeabilities from the output of this instrument are fairly well-established. However, what is hardly established is a sampling strategy that guarantees adequate representation...

A satire about my PhD endeavour.

Flocculation is one of the main process of sedimentation which modifies suspended particulate matter (SPM) characteristics, i.e. size and settling velocity. A combination of physical, chemical and biological parameters control coagulation and fragmentation of natural samples. A newly developed instrument, the Video In Lab, was used to monitor the k...

MANNING, A. Acquisition of in-situ images of real estuarine mud flocs is a recent (during the past ten years) development. Furthermore, images coupled with the corresponding floc characteristics offer distinct advantage over previous studies. Therefore, an improved understanding of floc structure (e.g. size and shape) and composition (e.g. porosity...

The following values have no corresponding Zotero field: ID - 196

Methodology to include effect of small heterogeneities in petroleum reservoir simulators

For over a century the Seine estuary has been highly affected by human activities, resulting in a reduction of the surface of wetland habitat. Several ponds of the Vernier Marsh, one of the main wetlands of the estuary, are being filled in by sediment. The St. Aubin canal, the only inlet from the Seine to the wetland, has regularly been opened in s...

Small-scale heterogeneities have a significant effect on the behaviour of fluid flow through a reservoir, since capillary forces trap the non-wetting phase in the high-permeable parts of a water-wet porous medium. An upscaling procedure must therefore be able to account for reservoir structure as well as for relative permeabilities and capillary pr...

Please correct co-author Geel: it is not Willem van Geel, but C.R. Geel.

Probe- or mini-permeameters are used for a quick determination of permeability distributions both in the field and in the laboratory. Based on designs of portable equipment, a fully automated probe has been developed for laboratory use. It allows the measurement of 100 values in an hour while scanning a sample on a dense grid. Thus heterogeneity on...

Introduction Groundwater has recently received increased attention especially in arid and semi-arid regions due to its potential to serve as an alternative water source. The potential for groundwater resources to be a sustainable source of water is affected by various factors, e.g. recharge rates, hydraulic properties, groundwater quality, etc. Qua...

This thesis presents a hierarchical and geologically constrained deterministic approach to incorporate small-scale heterogeneities into reservoir flow simulators. We use a hierarchical structure to encompass all scales from laminae to an entire depositional system. For the geological models under consideration we propose a five-scale hierarchy with...