Sequence-stratigraphic architectures and sand-body distribution in Cenozoic rifted lacustrine basins, east China

Abstract

A B S T R A C TCenozoic rifted lacustrine basins in east China display three main basin types: (1) basins with steeply dipping boundary fault, whose hanging walls tilt along pivot points; (2) basins with listric boundary faults, whose hanging walls bend along flexural bending points; and (3) basins formed by earlier extensional rifting with later strike-slip movement superimposed.The sequence development is intimately linked to the tectonic movements in the area, where second-order sequences are regionally correlatable from basin to basin and relate to the largescale tectonic movements in the region. Third-order sequences are related to local tectonic activity and are correlatable within basins, between subbasins, and sometimes, between neighboring basins. Detailed sequence-stratigraphic analysis and mapping of depositional systems demonstrate that sand-body distribution patterns are related to sequence-stratigraphic frameworks. For the three kinds of basins, the positions of pivot point zones, flexural bend zones, and strike-slip faults plus the syndepositional faults all control the distribution of depositional systems, systems tract, and sand bodies. These controlling factors can be attributed to different structural and stratigraphic features that change the accommodation. Structural elements include boundary faults, syndepositional faults, and abrupt changes in dip. Stratigraphic controls include preexisting surfaces with local channelization, paleobathymetric lows, and onlap onto clinoform slopes. The lowstand sand bodies deposited at the downdip A U T H O R S

Sequence stratigraphy and its application in marine shale gas exploration: A case study of the Lower Silurian Longmaxi Formation in the Jiaoshiba shale gas field and its adjacent area in southeast Sichuan Basin, SW China

“…As an integrated approach, sequence stratigraphy, after nearly forty years development, has been applied to siliciclastic and carbonate deposits in depositional settings from lacustrine to deep water settings and led to great success in conventional clastic and carbonate petroleum exploration (Vail et al, 1977;Van Wagoner et al, 1990;Miall, 1991;Schlager, 1992;Weimer et al, 1998;Posamentier and Allen, 1999;Catuneanu, 2002;Catuneanu et al, 2009;Jiang et al, 2013;Hemmesch et al, 2014). However, little research has been done to study the sequence stratigraphy of shale strata deposited in deep water environment (Slatt and Rodriguez, 2012).…”

Multiple-stacked Hybrid Plays of lacustrine source rock intervals: Case studies from lacustrine basins in China

“…Due to the relatively smaller size of lacustrine water bodies, lakes experience higher rates of environmental change compared to marine systems, resulting in small reservoir bodies characterized by rapid lateral and vertical facies changes, sensitivity to climate, broad ranges of salinity, pH, etc. (Kelts 1988;Graham et al 1990;Lambiase 1990;Carroll and Bohacs 1999;Bohacs et al 2000;Cohen 2003;Gierlowski-Kordesch 2010;Jiang et al 2013a).…”

Sequence Stratigraphy of Fine-Grained “Shale” Deposits: Case Studies of Representative Shales in the USA and China

“…Sequence stratigraphy is a relatively new concept of stratigraphy and is a powerful tool to subdivide the stratigraphic intervals into geologically realistic and cyclic patterns and to predict the stratal patterns, the lithofacies variations, and the petroleum reservoirs within a chronostratigraphic unit. In the past 40 years, the sequence stratigraphic studies mainly focused on the coarse-grained siliciclastic and carbonate deposits and on the fine-grained turbiditic systems from lacustrine to deepwater settings, leading to a great success in the conventional petroleum exploration [1][2][3][4][5]. However, only limited studies on the high-frequency sequence and sedimentology have been conducted to study the sequence stratigraphy of shale strata deposited in deep water or restricted shallow water environment [6][7][8].…”