Processing results from drill hole VNIIO-1989-24 in the Murmanskaya Area, southern part of the South Barents Deep (Report 6383, Leningrad)


Area of drilling: Murmanskaya area, southern part of the South Barents Deep, Barents Sea.Reasons for drilling:1. Study of the geological section from the longest drill hole in the South Barents Sea recovered Late Permian, Triassic and Jurassic deposits.2. Obtaining data for stratification of the section and its allocation with reflecting seismic horizons;3. Study of properties, composition and lithologic-facial features of sedimentary rocks.Technical results:The hole has penetrated the section of 4373 m and stopped in the Late Permian deposits. This section is the thickest in the Muramnsk area.Scientific results:1. Comprehensive study of the Late Permian, Mesozoic and Cenozoic deposits from the hole has allowed to reveal lithologic features and to carry out a detailed lithologic and stratigraphic sequence of sedimentary rocks. Permian deposits have been reliably identified on the base of obtained lithologic and paleontologic materials (foraminifera, palynology) from Permian-Triassic to Early Cretaceous ones. 2. Thicknesses of the units are as followed: Permian-Triassic - 1322 m, Early Triassic - 241 m, Middle Triassic - 403 m, Late Triassic - 416 m, Early Jurassic - 287 m, Middle Jurassic (Aalenian-Bathonian) - 348 m, Late Jurassic - 117 m (Callovian-Kimmeridgian - 91 m, Tithonian - 26 m), Early Cretaceous - 1239 m (Berriasian-Hauterivian - 39 m, Barremian-Aptian - 501 m, Albian - 699 m). The question about presence or absence of Late Cretaceous and Paleogene deposits (mapped in the South Barents Deep) in the section remains undetermined. Presumably these deposits have low thickness and occur above the sampling interval.3. Sedimentation rate varied from 0.3 cm/kyr in the Late Jurassic to 10 cm/kyr in the Early Triassic.4. Pre-Valanginian washout and weathering crust as well as pre-Cenozoic washout have been identified. Hiatuses are assumed in the post-Jurassic, post-Valanginian, and pre-Cenozoic time.5. Clayey-silty sedimentary rocks dominate in the hole. Silty-sandy rocks dominate in the Permian, Triassic, Early and Middle Jurassic.6. Coals of gas stage metamorphism occur in the Permian, Late Triassic, Middle Jurassic and Late Aptian deposits.7. Sedimentation environment has been reconstructed. Permian-Triassic sediments accumulated in lagoonal-continental and lagoonal-marine conditions. Triassic to Early Jurassic sediments accumulated in lagoonal-continental and continental conditions. Middle-Late Jurassic and Cretaceous sediments accumulated in a mainly shallow marine basin. In the end of the Late Jurassic this basin deepened.8. Maximal downwarping was in the Permian, Triassic and in the end of the Early Cretaceous.9. Sedimentary rocks are lithified from ones affected by deep epigenesis (Permian-Triassic) to ones affected by early epigenesis (Early Jurassic Early Cretaceous).10. Mineral composition of sedimentary rocks from the Murmansk area strongly differs from one of deposits in the Kolguev Island and the Timan-Pechora region.11. During the Late Jurassic black clays enriched in organic matter accumulated. This resulted from scarcity of sedimentary material, very low sedimentation rates, and a rather deep basin of sedimentation.

Metadata Access
Creator Ronkina, Zinaida Z; Komarnitsky, Valery M
Publisher PANGAEA
Contributor All-Russian Research Institute for Geology and Mineral Resources of the World Ocean, St. Petersburg
Publication Year 1989
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Language English
Resource Type Publication Series of Datasets; Collection
Format application/zip
Size 3 datasets
Discipline Earth System Research
Spatial Coverage (39.033 LON, 70.083 LAT); Barents Sea