J 2017

Mineralogical characteristics of upper Jurassic Mikulov Marls, theCzech Republic, in relation to their thermal maturity

SEDLÁKOVÁ, Iva, Eva GERŠLOVÁ, Petr UHLÍK and Vladimír OPLETAL

Basic information

Original name

Mineralogical characteristics of upper Jurassic Mikulov Marls, theCzech Republic, in relation to their thermal maturity

Authors

SEDLÁKOVÁ, Iva (203 Czech Republic, guarantor, belonging to the institution), Eva GERŠLOVÁ (203 Czech Republic, belonging to the institution), Petr UHLÍK (703 Slovakia) and Vladimír OPLETAL (203 Czech Republic)

Edition

Chemie der Erde – Geochemistry, Jena, Elsevier, 2017, 0009-2819

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10505 Geology

Country of publisher

Germany

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 1.723

RIV identification code

RIV/00216224:14310/17:00096274

Organization unit

Faculty of Science

UT WoS

000401042700011

Keywords in English

Mikulov Marls; Smectite illitization; Bulk mineralogy; Thermal maturity

Tags

Tags

International impact, Reviewed
Změněno: 9/4/2018 12:40, Ing. Nicole Zrilić

Abstract

V originále

The Upper Jurassic Marls of Mikulov present a formation that is considered to be the most promising strata to produce hydrocarbons in the Vienna basin. The marls are composed of dark pelagic marlstones that frequently contain layers of limestone with thickness reaching several hundreds of meters. Twenty-seven core samples from selected wells located in the south-eastern portion of the Czech Republic representing depths ranging from 2300 to 4500 m were analyzed by x-ray diffraction to assess bulk mineralogy and the progress of smectite illitization.Bulk mineralogy of the Mikulov Marls comprises carbonates (mean value = 54.4 mass%), clay minerals(26.6 mass%), quartz (15.0 mass%), and feldspar (1.6 mean%). In the decreasing order, the clay mineral fraction is composed of illite/mica, kaolinite, illite-smectite, and chlorite. The amount of smectite inillite-smectite decreases with depth from 70% to 28%. There is a change from random to ordered inter-stratification at the depth of 3300 m. The transition from short-range ordering (R1) to long-range ordering(R3) occurs at depths greater than 4,500 m. There was a good correspondence between thermal maturity parameters: the percentage of smectite in illite-smectite structures and vitrinite reflectance as a parameter of organic matter. The increase of the metamorphic grade was compared in respect to the geothermal gradient with adjacent basins.