Posted Monday July 13th, 2015, 10:12 am
An independent, regional chemostratigraphic correlation has been constructed for the Cretaceous and Jurassic successions penetrated by offshore wells from across the Grand Banks area and includes key exploration wells from the: Orphan, Flemish Pass, Jeanne d’Arc and Carson basins, in addition to wells from the Outer Ridge Complex. Geochemical data have been collected via ICP instruments from a total of 28 wells, with a further 24 wells currently under investigation (data available from early September, 2015).
Cuttings samples were collected from base Tertiary through to TD, with a focus on the Jurassic and Cretaceous successions and includes the organic-rich source rock intervals of the Rankin Formation and the prolific, syn-rift sandstones of the Jeanne d’Arc, Fortune Bay, Hibernia and Avalon units. An independent chemostratigraphic correlation, comprising first, second and third-order chemostratigraphic divisions, was developed across the study area and integrated, where possible, with existing lithostratigraphic and biostratigraphic data, providing a high resolution stratigraphic framework with which to calibrate wireline and seismic based correlations. The chemostratigraphic correlation is based on up-sequence variations in key elements and elemental ratios reflecting changes in lithology, clay mineralogy, heavy mineral and feldspar assemblages and organic matter preservation. Furthermore, spatial variations in these mineral phases allows for inferences to be made regarding sediment input and organic preservation.
The elemental data used to produce the chemostratigraphic zonations and correlations have been further utilised to calculate mineralogy (ChemMin) and TOC over the well sections. The predicted mineralogy was calibrated against a sub-set of XRD data to provide a tailored and high-resolution mineralogical model across the entire Grand Banks area, utilising a fraction of the XRD analyses that would otherwise be required. The resultant mineralogical logs provide a strong visual summary of the bulk mineralogy across the analysed successions in each well, as well as providing a means of quickly assessing which minerals principally control the E-log responses. Although the geochemical data acquired is inorganic in nature, there are elements within the dataset that can be associated with organic material, for example U, Mo and Ni. Using the same principals developed for the mineral modelling described above, it was possible to estimate relative TOC abundance using elemental proxies, with this data being further supplemented and calibrated with acquired TOC data.
In addition to the extensive Grand Banks dataset, geochemical data have been acquired from the nearby Hopedale and Saglek basins (offshore Labrador) and Scotian Margin (including the Scotian Shelf and Scotian Slope) with a total of 24 wells being analysed to date.
Wells can be purchased individually or as area parcels. The data and interpretations are presented in a GIS-based data package which includes raw data (.xls, .csv), tabulated tops, key figures, chemical maps and study report – AVAILABLE NOW. Further details on the study can be found here.
Posted Tuesday May 26th, 2015, 2:35 pm
A robust regional chemostratigraphic correlation has been constructed for the Namurian to Westphalian successions penetrated by onshore wells within the Gainsborough Trough, Edale Basin, East Midlands Shelf, Humber Basin, Askern-Spital High, Cleveland Basin, Bowland and Blacon Basin. A total of 36 wells from the UK onshore Carboniferous have been analysed with full ICP data, XRD, TOC, δ13Corg stable isotope analysis and palynological data. However due to limited sample volume some wells have had elemental data acquired by a calibrated handheld XRF, while a calibrated FTIR has been used to determine whole rock mineralogy.
This study focuses on the informally named ‘Bowland-Hodder unit’, typically, a high gamma ray interval located above Dinantian aged strata. This succession consists of silty claystones and siltstones that are distributed across northern England. Sandstones are localised and are thought to be associated with the progradation of deltaic systems from the North East. High calcareous lithologies are associated with the occurrence of the carbonate platforms, and the calcareous turbidite deposits derived from them. The study intervals have been subdivided into a series of chemostratigraphic sequences, and packages, on the changes in key elements and ratios based on lithology, heavy minerals, organic matter and clay minerals/feldspars. A high resolution stratigraphic framework that can used to calibrate wireline and seismic based correlations.
The elemental data used to erect the chemostratigraphic zonation and correlation have been used to predict the mineralogy (ChemMin) of all the analysed samples, allowing the construction of the mineralogical logs. The predicted mineralogy is calibrated against the sub set of XRD mineralogical data. This approach is advantageous as it converts the elemental data into minerals proportions, which are easily understood by geologists. In addition, mineralogical logs can be used to calibrate mineralogical models established by petrophysicists from E-log responses; as well as providing a relative brittleness index (ChemRBI). Using ChemMin mineralogical logs can be rapidly acquired from geochemical datasets from large numbers of samples and wells. Unlike XRD, which can vary from contractors, are typically time consuming and expensive. The logs provide a strong visual summary of the bulk mineralogy of the analysed successions in each well, as well as providing a means of quickly assessing which minerals principally control the E-log responses.
Redox conditions have also been determined using inorganic elemental datasets and TOC data. U, Mo, Cr, Co, Ni, Cu and S, Zn are potentially useful for highlighting variations in redox conditions (Tribovillard et al. 2006) as they are more soluble under oxidising conditions and less soluble under reducing conditions.
Chemostrat have already used the chemostratigraphic zonation from this study to provide offset well control for a wellsite chemostratigraphy deployment in the Bowland play.
Posted Thursday May 7th, 2015, 12:28 pm
Chemostrat has built an unrivalled reputation for providing and interpreting the highest quality laboratory data over the past quarter of a century.
We have worked in most basins around the world, providing elemental, mineralogical, isotopic and organic geochemical data and interpreting those data to deliver meaningful stratigraphic correlations. We have also carried out numerous studies in many North American shale plays, implementing not only high-resolution stratigraphic analysis, but a full array of Shale Solutions. With our wellsite services we are bringing this experience to wellsite as well as using state-of-the art instrumentation to provide inorganic whole rock geochemical data, mineralogical data and magnetic susceptibility data.
Our elemental data are collected using small compact XRF instruments that require minimal sample preparation (no heavy cumbersome pellet press required), yet yield data of a quality similar to that of larger instruments in a matter of minutes.
Our mineralogical data are collected using highly portable Fourier transform infrared (FTIR) instruments which determines bulk mineralogy and TOC indication from small samples in minutes. Magnetic susceptibility data provides detection of magnetic minerals to aid in the identification of sequence stratigraphic boundaries.
According to John Martin, Director for Chemostrat wellsite, “The new wellsite website will provide an informative user experience for our clients. As an integral part of our ambitious growth plans for the next three years, we recognised that we needed to develop a brand in line with the aspirations of the company. We needed a strong, new identity that communicates the message that we offer far more than chemostratigraphy to clients worldwide. Simplified site navigation and enhanced search capability” John continued “make it quick and easy for the visitor to find the appropriate service to suit their needs.”
Posted Thursday December 11th, 2014, 10:48 am
The Board of Directors of Hafren Scientific Ltd (the ‘Company’) is pleased to announce the appointment of Dr Carol Bell as Non-Executive Chairman with effect from the 1st December 2014, Dr Bell will succeed Dr Tim Pearce (acting Chairman).
Dr Bell read Natural Sciences before starting her career in oil and gas industry and moving into investment banking where she held senior posts at JP Morgan and the Chase Manhattan Bank oil industry finance. Dr Bell also has considerable board experience serving as a Non-Executive Director in a number of companies in the oil and gas industry. She currently serves on the board of Salamander Energy plc and Petroleum Geo-Services ASA, having previously been a board member at Hardy Oil and Gas plc, Det norske oljeselskap ASA and Caracal Energy Inc. She is also a member of the Welsh Government Energy and Environment Sector Panel and serves on the board of Finance Wales.
Commenting, Dr Pearce said, ‘I am delighted that the Board has appointed Carol Bell to succeed me as Chairman. She has a distinguished track record in the oil industry and as an international businesswoman and she is the ideal person to chair the Board through our ambitious agenda.’
Dr Bell commented ‘The oil and gas industry is constantly having to develop new scientific techniques to improve the chance of finding and developing new resources around the world. I am very pleased to have the chance to work with innovative scientists, based in Wales, that are building an international reputation in this field.‘
Posted Tuesday October 7th, 2014, 10:20 am
Three new team members joined Chemostrat Ltd over the summer.
Dr. Luca Caracciolo – Senior Geologist, Sandtrak Manager
Luca graduated the University of Calabria in 2005, and gained his PhD in 2009. From 2009 to present he developed his EU community funded Post-doctoral research in the Thrace basin (NE Greece, SE Bulgaria and NW Turkey) at the Universities of Calabria (Italy) and Goettingen (Germany). His research is focused on the application of a wide spectrum of Provenance analysis techniques to basin analysis, particularly on the relationships between tectonic and sedimentation. His main skills are: - Quantitative and qualitative sedimentary provenance analysis; Sedimentary petrology and detrital geochemistry; sedimentary processes (weathering / recycling, volcaniclastic sedimentation) diagenesis (cementation chronology, pore-water interaction, thermal history), Low temperature thermochronology (Fission tracks and U/Th/He dating). Luca has had the chance to work around the world, including Southern California, Spain, The Alps, Czech Republic, SW Europe, Morocco and the Mediterranean Basin.
He is currently the National Correspondent for Italy of IAS (International Association of Sedimentologists). He is also the secretary of a European network of geoscientists (Goettingen, Delft, Madrid, Milan, Calabria, UCL (London), Dublin, Bern, Darmstadt), the WGSG (Working Group on Sediment Generation).
Luca will be heading up the Sandtrak team, our specialist provenance unit which is currently involved in multi-clients studies from the North Sea, Barents Sea, Irish Atlantic margin, WOS and Tanzania.
Marta Barbarano – Geologist
Marta Graduated from Milano-Bicocca University, Milan in 2013, with a Master in Geology. Through her Bachelor and Master she developed a background in different disciplines, including Sedimentology, Stratigraphy, Structural Geology and Geological Mapping, studying also in Utrecht University. She has been involved in a research project focused on the provenance analysis of sandstones from Corsica, characterising the Heavy Minerals composition of the sandstones and mapping the geology of the study area. Marta continued to work as field geologist for her Master thesis, combining structural data with geomorphological and geotechnical data, in order to build up a multidisciplinary description of a Deep-Seated Gravitational Slope Deformation. She has also done an internship in Geotechnics in Seville.
Marta will join the geological team undertaking heavy mineral analysis and provenance studies as part of the Sandtrak team.
Dr Eliza Mathia - Senior Geologist
Eliza graduated from Warsaw University, Poland in 2007, obtaining a Master’s degree in Geology, major in Geochemistry, Mineralogy and Petrology. She continued her education at Newcastle University, UK, where, in 2010, she completed an MSc course in Petroleum Geochemistry. Eliza’s dissertation focused on modelling of the distribution of organic rich sediments off-shore Namibia. Following on, she enrolled on a PhD program, graduating in 2014. Eliza’s PhD research was part of the industry-funded project Gas Shales in Europe, with a particular focus on the evolution of pore systems in shales.
Eliza will provide Chemostrat with specialist organic geochemical interpretative services and devise innovative methods to model anoxia, organic preservation and ‘sweet spot prediction’ in shale resource plays