North Sea (UK, Norway, Denmark & Holland)
The North Sea is one of PetroStrats core areas. We have particularly strong, state-of-the-art expertise in the following areas and stratigraphic sections:
Tertiary Clastics (Early Palaeocene to Pliocene)
PetroStrat has extensive experience of the Tertiary stratigraphy of North West Europe, including the Central and Viking Graben areas, having assisted in the development of >35 UKCS fields that produce from Eocene and Palaeocene reservoirs, providing wellsite services on over 80 wells (in order to help pick casing points and/or monitor reservoir stratigraphy).Our high resolution approach has enabled subdivision of Eocene sands within the Frigg, Tay, and Skroo depositional systems of the lower Horda Formation (Unit H1), and within the Balder and Sele Formations. In addition, detailed subdivision of the Middle Eocene Horda Formation (Unit H2) at wellsite has permitted accurate positioning of casing points above Tay reservoir sands.Within the ‘earliest’ Eocene we have helped to differentiate sands within units S3 (Gannet) and S2a (Bittern) of the Sele Formation, in addition to the S2B (Cromarty) sands. Differentiation of these Sele sand units (via high resolution biostratigraphy) has proven vital to the development of post Forties reservoir sands in several fields including Bittern and Gannet D.
PetroStrat has unrivalled experience in the palynostratigraphy of the Forties Sandstone Member, having undertaken intensive studies on over 150 well sections from 20+ fields that produce from Forties reservoirs. We have demonstrated that Forties sands vary in age from field to field, and between wells within individual fields. We are actively involved with development drilling on several fields, providing non-acid wellsite palynological services to assist with picking casing points and geo-steering highly deviated and horizontal wells.
Within the Palaeocene, PetroStrat have a wealth of experience within the Lista and Maureen Formations of the UK sector and Norway, having completed studies on the Andrew/Heimdal and Maureen/Ty sands in the Viking Graben and on the Andrew/Mey and Maureen sands of the Central Graben area, in both the UK and Norwegian sectors.
Chalk (Late Cretaceous and Early Palaeocene)
We have vast experience in many of the Chalk Group developments in the North Sea, including wellsite monitoring or “biosteering” of many long-reach development wells in the UK, Norwegian, Danish and Dutch sectors. We have developed and improved zonations scheme and realtime data delivery in Danian to Turonian aged sections with extensive experience in the Ekofisk, Tor and Hod/Mackerel Formations. This experience has been complimented by casing pick work on approach to depleted crestal structures and montoring wellbore stability in overburden sections. We continue to develop our palaeoenvironmental and facies interpretations in these important reservoirs.
PetroStrat personnel have extensive biostratigraphic experience of Early Cretaceous Fields and single exploration wells throughout the UK North Sea including the Central Graben, Fisher Bank, South Viking Graben, North Viking Graben and West of Shetlands. This has often included extensive multi-well re-analysis/review of previous biostratigraphic data of variable quality and vintage, followed up by infill analysis. In addition we have worked on Danish Early Cretaceous Reservoirs including the Valdemar, Tyra and Adda fields, extensive review of vintage data and re-analysis of Lower Cretaceous sections.This work has included numerous wellsits in the UK, Norwegian, Danish and Dutch sectors, including horizontal biosteering in Early Cretaceous reservoirs and assisting casing and coring picks within the Cromer Knoll Group.
We have strong expertise in North Sea Jurassic micropalaeontology/palynology and stratigraphy, having completed numerous well studies including multiwell correlations and wellsite support work. We also have expertise in radiolaria, useful in HPHT wells, following John Gregory’s Ph.D. research and Brent Group sections following Nick Butlers Ph.D. research. PetroStrat has considerable experience in integration and re-interpretation of large regional datasets (biostratigraphy, lithostratigraphy and sequence stratigraphic correlations) within the Moray Firth, Central and Viking Grabens and Mid-Norway. Micropalaeontology has proven invaluable during wellsite monitoring of HP/HT wells where palynology is not viable (due to steep thermal maturation gradients).
Triassic – Permian North Sea
Petrostrat has significant experience in Triassic palynology from the North Sea (Skagerrak, Lunde, Lomvi, and Teist Formations). Within the Central North Sea, PetroStrat have also undertaken several studies that builds on recent Ph.D. research at the University of Aberdeen (Roger Burgess) allowing for identification and correlation of the J-member sequences from the Skagerrak Formation. PetroStrat has also provided well-site services within the Central Graben Area of the North Sea Central, where a multidisciplinary approach combining palynology with chemostratigraphy was utilised to identify and monitor Triassic sediments. This experience is supported by a wealth of experience in the northern hemisphere from a wide range of regions including North Africa (Triassique Argilo-Greseux Inferieur), Eastern Mediterranean (Sabunsuyu, Areban and Uludere Formations), Canada and the Permo-Triassic of the Barents Sea (Flatsalen, De Geerdalen, Tschermakfjellet and Botneheia Formations).
Southern North Sea Carboniferous
PetroStrat have accumulated experience in the Carboniferous of the Southern North Sea in recent years. Our staff have worked to provide real-time biostratigraphic monitoring starting in the Conybeare Group (Westphalian, Caister Coal Formation). Typically, these wells have targeted Namurian (Alportian/Chokierian, Millstone Grit Formation) reservoir targets, but also include work penetrating the Bowland Shale Formation in search of deeper Visean Limestone plays. In addition to wellsite services, our team have undertaken post-well analyses of samples processed by our in-house laboratory technicians. We have also worked on the Carboniferous of the Barents Sea.
Our personnel have considerable experience within the Black Sea and Caspian Sea region, having worked on many well sections of various stratigraphic ages in Azerbaijan, Bulgaria, Kazakhstan and Romania. PetroStrat also has significant experience in Poland.
PetroStrat experience includes four extensive well sections in south-east Poland, penetrating stratigraphic sections of Late Cretaceous to Palaeozoic age. Real-time wellsite biostratigraphy was also carried out on the Palaeozoic intervals of two of the wells.
PetroStrat experience encompasses biostratigraphic analysis of Tertiary intervals in six offshore wells in the Black Sea. Outcrop samples have also been analysed.
PetroStrat experience includes palynological analysis of three well sections from north-east Romania, predominantly of Palaeozoic age.
John Gregory (one of the PetroStrat directors) has unique experience gained over 10 years working in academic association with CASP (Cambridge Arctic Shelf Programme). He has conducted micropalaeontology analyses and been involved in stratigraphical integration of ammonite-dated, Jurassic and Cretaceous on-shore sections (>100 separate localities in Kangerlussaq, Hold with Hope, Geographical Society O, Wollaston Foreland, Clavering O, Jameson Land and Milne Land). In addition, he has studied previously un-recognised Tertiary sections.
Additional related Boreal experience has been gained of Jurassic outcrop successions from Svalbard (Spitsbergen).