DOI: 10.1306/04021312122
Scopus记录号: 2-s2.0-84880817968
论文题名: Episodic and simultaneous illitization in oil-bearing brent group and fulmar formation sandstones from the northern and southern north sea based on illite k-ar dating
作者: Clauer N. ; Liewig N.
刊名: AAPG Bulletin
ISSN: 0149-1625
EISSN: 1558-9355
出版年: 2013
发表日期: 2013
卷: 97, 期: 12 起始页码: 2149
结束页码: 2171
语种: 英语
Scopus关键词: Crystallization temperature
; Geothermal gradients
; Illite-smectite
; Illitization
; Mixed layer
; Size fraction
; Southern North Sea
; Temperature increase
; Hydrostatic pressure
; Kaolinite
; Transmission electron microscopy
; Sandstone
; acceleration
; chlorite
; crystallization
; deposition
; hydrocarbon
; hydrostatic pressure
; illitization
; kaolinite
; sandstone
; subsidence
; temperature effect
; Atlantic Ocean
; North Sea
Scopus学科分类: Energy
; Earth and Planetary Sciences
英文摘要: Size fractions (<0.4 and 0.4-1.0 μm) of Brent Group sandstones from the northern North Sea contain mostly illitesmectite mixed layers with kaolinite, whereas the same size fractions of Fulmar Formation sandstones from the southcentral North Sea consist of illite-smectite mixed layers with minor chlorite. Transmission electron microscope observations show elongated illite laths or agglomerates consisting of small laths when larger individual laths are lacking. The K-Ar data of the fractions less than 0.4 pm of Brent Group samples plot on two arrays in a 40Ar/36Ar vs. 40K/36Ar diagram that have isochron characteristics with ages of 76.5 ± 4.2 and 40.0 ±1.5 Ma, and initial 40Ar/36Ar ratios of 253 ±16 and 301 ± 18, respectively. For the Fulmar Formation sampies, the data points of the fractions less than 0.2 and less than 0.4 pm also fit two isochrons with ages of 76.6 ±1.4 and 47.9 ± 0.5 Ma and initial 40Ar/36Ar ratios of 359 ± 52 and 304 ± 2, respectively. Some of the coarser 0.4-1.0-μm fractions also plot on the two isochrons, but most plot above indicating the presence of detrital components more than 0.4 μm. The almost identical ages obtained from illite-type crystals of sandstones with different deposition ages that are located about 600 km (373 mi) apart record two simultaneous illitization episodes. These events were not induced by local burial conditions, but are related to episodic pressure and/or temperature increases in the studied reservoirs, probably induced by hydrocarbon injection. This interpretation is indirectly supported by notably different K-Ar illite ages from cores of a nearby reservoir at hydrostatic pressure. Illite is not as well crystallized as expected for potential crystallization temperatures above 160°C measured by fluidinclusion determinations. In both the northern and south-central North Sea, the two illite generations remain unaffected after crystallization despite continued burial, suggesting notably higher crystallization temperatures than those estimated from geothermal gradients. No recent illite crystallization or alteration is recorded in the K-Ar ages, despite a dramatic regional acceleration of the subsidence in the southern North Sea. Copyright © 2013. The American Association of Petroleum Geologists. All rights reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84880817968&doi=10.1306%2f04021312122&partnerID=40&md5=0044f5ad769bae426c904aac0e369759
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/13195
Appears in Collections: 过去全球变化的重建 影响、适应和脆弱性 科学计划与规划 气候变化与战略 全球变化的国际研究计划 气候减缓与适应 气候变化事实与影响
There are no files associated with this item.
Recommended Citation:
Clauer N.,Liewig N.. Episodic and simultaneous illitization in oil-bearing brent group and fulmar formation sandstones from the northern and southern north sea based on illite k-ar dating[J]. AAPG Bulletin,2013-01-01,97(12)