scholarly journals Topographic Constraints on the Evolution and Connectivity of Titan's Lacustrine Basins

2017 ◽  
Vol 44 (23) ◽  
pp. 11,745-11,753 ◽  
Author(s):  
A. G. Hayes ◽  
S. P. D. Birch ◽  
W. E. Dietrich ◽  
A. D. Howard ◽  
R. L. Kirk ◽  
...  
Keyword(s):  
Topographic Constraints ◽  
Lacustrine Basins

scholarly journals Geoenvironmental Implications and Biocenosis of Freshwater Lakes in the Arid Zone of East Kazakhstan

2021 ◽  
Vol 13 (10) ◽  
pp. 5756
Author(s):  
Talant N. Samarkhanov ◽  
Anar B. Myrzagaliyeva ◽  
Jiri Chlachula ◽  
Ludmila B. Kushnikova ◽  
Jolanta Czerniawska ◽  
...  
Keyword(s):  
Central Asia ◽  
Arid Zone ◽  
Anthropogenic Impacts ◽  
Benthic Fauna ◽  
Steppe Zone ◽  
Taxonomic Composition ◽  
Nature Protection ◽  
Aquatic Biomass ◽  
East Kazakhstan ◽  
Lacustrine Basins

Steppe and semi-desert lakes of Central Asia represent unique and still poorly known aquatic ecosystems. The paper provides summaries of multi-proxy environmental and biological investigations of the previously unexplored ground of Sibe lakes in the naturally pristine zone of East Kazakhstan, and of their contributions to people. Data on the taxonomic composition of zooplankton and zoobenthos of these freshwater lacustrine basins are presented in terms of the species’ frequency of occurrence; the abundance of the aquatic biomass and the analyzed water geochemical variables insofar as they are dependent and correlative. The qualitative and quantitative records display variability in the biocenosis diversity due to the lakes’ geochemistry and hydrology differences—some lakes being oligotrophic and others being moderately trophic. In the latter case, the lakes characterized by an increased macrozoobenthos biomass are favourable for local ichthyofauna. Sapro-biological analysis reveals the predominance of β-saprobic species in the zooplankton composition pointing to slight or moderate pollution of surface waters due to natural biotic substances. This observation is in agreement with differences in the water quality of solitary lakes. The uneven distributions of benthic invertebrates (in terms of taxonomy and species populations) in the water bodies suggest specific hydro-ecological conditions that predetermine the structure of the lakes’ biocenosis. The littoral part of the lakes is characterized by the highest abundance of zooplankton and benthic fauna. The Sibe lakes are an example of an autonomous functioning of the lacustrine basins in the upland arid steppe zone, which is characterized by pronounced climate “continentality” and a high level of the sub-aquatic flora and fauna endemism. The present results are relevant to the understanding of the ecosystems’ dynamics and the modern anthropogenic impacts upon the pristine parkland-steppe landscapes of Central Asia, with implications for regional nature protection and sustainable eco-recreation.

scholarly journals Paleotopographic controls on facies development in various types of braid-delta depositional systems in lacustrine basins in China

2015 ◽  
Vol 6 (4) ◽  
pp. 579-591 ◽  
Author(s):  
Dong Feng ◽  
Hongwen Deng ◽  
Zhan Zhou ◽  
Xiaopeng Gao ◽  
Longtao Cui
Keyword(s):  
Depositional Systems ◽  
Lacustrine Basins

Massive ground ice and ice-cored terrain near Sabine Point, Yukon Coastal Plain

1988 ◽  
Vol 25 (11) ◽  
pp. 1846-1856 ◽  
Author(s):  
D. G. Harry ◽  
H. M. French ◽  
W. H. Pollard
Keyword(s):  
Coastal Plain ◽  
Yukon Territory ◽  
Ground Ice ◽  
Flow Slides ◽  
Petrographic Analyses ◽  
Multiple Cycles ◽  
Lacustrine Basins

Massive ground ice, 5–6 m in thickness, is exposed within retrogressive thaw flow slides near Sabine Point, Yukon Territory. The ice is present near the upper surface of Buckland Till and is overlain and thaw truncated by mudflow sediments and a thick unit of peat and organic silt. Cryotextural and petrographic analyses suggest that the ice formed primarily by segregation processes. The ice occurs within an area of rolling terrain, surrounded by lacustrine basins. This may form a remnant of an initial post-Buckland surface, degraded by multiple cycles of thermokarst during the period 14 000 to 8000 years BP.

The characteristics of tight oil sand reservoir-source assemblage in lacustrine basins: A case study of the Cretaceous Qingshankou Formation, Songliao Basin, northeast China

2018 ◽  
Vol 6 (2) ◽  
pp. T299-T311 ◽  
Author(s):  
Yaohua Li ◽  
Yan Song ◽  
Zhenxue Jiang ◽  
Lishi Yin ◽  
Mo Chen ◽  
...  
Keyword(s):  
Lake Level ◽  
Songliao Basin ◽  
Qualitative Description ◽  
Hydrocarbon Potential ◽  
Tight Oil ◽  
Sweet Spot ◽  
Oil Sand ◽  
Tight Reservoir ◽  
High Lake Level ◽  
Lacustrine Basins

The complicated source-reservoir-assemblage characteristics of lacustrine tight oil sand in China are the main controlling factors of tight reservoir oiliness (i.e., oil richness). Several studies have focused on qualitative description of source-reservoir-assemblage characteristics without quantitative assessment. In this study, reservoir-source-assemblage (RSA) has been evaluated quantitatively by fitting the RSA log in the evaluation of Qijia Depression in the Songliao Basin. Total organic carbon (TOC) and sand volume (Vs) logs are used to fit the RSA log in three steps: (1) TOC and Vs log fitting and normalization, (2) RSA log fitting, and (3) extraction of root-mean-square (rms) amplitude and frequency (Frq(0)) information from the RSA log. The rms represents the reservoir capability and hydrocarbon potential, and Frq(0) represents the interbedding frequency that changes with the lake level. Positive values (0–1] of the RSA log correspond to a high lake level, whereas negative values [[Formula: see text], 0) correspond to a low lake level. Based on RSA log values, we defined the parameter RSAsuf, a product of rms and Frq(0), to quantitatively evaluate the tight oil sweet spot. RSAsurf serves as tight oil sweet spot indicator and correlates positively to oil richness. As a result, four types of effective reservoirs (RI, RII, RIII, and RIV), two types of effective sources (SI and SII), and three types of RSAs (R-S-R, S-R-S, and S-S-R) are identified based on cores and RSA logs. High RSAsuf values on the isoline map indicate the sweet spot zones around the G933 and J392 well areas, which correlates very well with the oilfield test data. The approach is appropriate for lacustrine basins with complicated RSA, in which RSA logs serve as indicator for the sedimentary rhythm, reservoir capability, and hydrocarbon potential.

Early hydrocarbon generation of biological lipids in non-marine lacustrine basins—a genetic mechanism of immature oil

1997 ◽  
Vol 40 (1) ◽  
pp. 54-64 ◽  
Author(s):  
Tieguan Wang ◽  
Dujie Hou ◽  
Ningning Zhong ◽  
Jianping Bao ◽  
Guanghui Huang ◽  
...  
Keyword(s):  
Genetic Mechanism ◽  
Hydrocarbon Generation ◽  
Immature Oil ◽  
Lacustrine Basins
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