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The accurate dating of prehistoric eruptions is essential for reconstructing volcanic sequences and for preparing volcanic-hazard assessments. The chronology of the eruptions of the Datong volcanic field (DVF) in eastern China has been debated for several decades, especially the start and end of volcanism. Loess sediments incorporated in explosive volcanic products have been described from the Dongpingshan scoria cone in the DVF. We conducted radiocarbon dating of the loess sediments, which produced an age of ~7300 cal yr BP for the Dongpingshan volcanic eruption. This result confirms the eruption of the DVF during the Holocene, and it provides important evidence for assessing volcanic hazards in this densely populated region. The Holocene age of the eruption indicates that DVF is dormant, contrary to previous studies which concluded that the DVF is extinct and that its volcanic eruptions ended at ~100 ka. In addition, this study documents a new method of dating Late Pleistocene to Holocene volcanic eruptions in and around the DVF, where loess sediments are widespread and may be preserved within volcanic products. • Datong is not an extinct volcanic field. • First radiocarbon dating of Datong volcanic field was present. • The most recent eruption of the Datong volcanic field was not older than ~7300 cal a BP. [ABSTRACT FROM AUTHOR]

Wudalianchi volcanic field (WDLC) is one of the youngest intracontinental monogenetic volcanic fields in China. The 1719–1721 CE Laoheishan-Huoshaoshan eruption, and the 1776 CE Laoheishan eruption are the latest eruptions in WDLC based on the local historical records. However, most of the recent explosive eruptive products around WDLC are attributed to the 1719–1721 CE Laoheishan-Huoshaoshan eruption while less attentions were paid on the 1776 CE Laoheishan eruption. There are two types of scoria fall deposits around Laoheishan volcano, i.e. the upper light grey high vesicular scoria deposit (US) and below dark low vesicular scoria deposit (BS). Most of the glass shards from US exhibit >4% Na 2 O while BS show <4% Na 2 O. In addition, US presents two different glass composition clusters, indicating a complex magma batch feeding the eruption. Broadly, all of these eruptive products from WDLC have extreme high potassium (usually >5%) content with trachyandesitic to tephriphonolitic in composition that can be clearly distinguished from those from other nearby volcanic regions, such as Nuomin (~150 km to Nangelaqiushan lake (NGLQ)), Arxan-Chaihe (~450 km to NGLQ), Longgang (~700 km to NGLQ) and Jingbohu (~550 km to NGLQ). A cryptotephra layer is clearly revealed as a distinct peak in magnetic susceptibility measurements from NGLQ ~ 8 km northwest to Laoheishan volcano. Glass composition of the cryptotephra layer recorded in NGLQ is similar to the proximal US around Laoheishan volcano. On basis of historical records and field observations, we ascribed US to the 1776 CE Laoheishan eruption and BS to the 1719–1721 CE Laoheishan-Huoshaoshan eruption. Consequently, historical records assigned a precise age (1776 CE) for the tephra recorded in NGLQ, and thus can be used to refine the age model of these lacustrine sediments. • Ash from the most recent eruption (1776 CE) in the Wudalianchi volcanic field was identified. • A cryptotephra layer from 1776 CE Laoheishan eruption was detected in the Lake Nangelaqiushan. • The 1776 CE Laoheishan and 1719–1721 CE Laoheishan-Huoshaoshan eruption show different glass composition. [ABSTRACT FROM AUTHOR]

"Maars and Environment" highlights maar research in China and sheds light on the wealth of information a maar volcano can store from the pure volcanology to understanding magma fragmentation to the sedimentology of deep lacustrine basins which record changing environmental conditions. Furthermore, maar volcanoes are the type of small-volume, monogenetic volcanoes where the rising magma can strongly influence the environment. This Special Issue will provide a snapshot of maar research especially from the maars and their environmental aspects. [Extracted from the article]

The sediments of maar lakes often provide paleoenvironmental records which are highly suitable for palaeoclimatic studies. The main advantages of the records from maar lakes compared with other lacustrine records are as follows: First, the presence of varves (annually laminated layers) and tephra layers, as well as other materials (like terrestrial plant macrofossils, charcoals, organic carbon, organic shells) suitable for isotopic dating (like AMS 14C, 210Pb, 137Cs, 238U/230Th, 40Ar/39Ar), provides the possibility of developing several independent chronologies, enabling the development of robust, high-resolution chronologies. Second, maars and maar lakes can provide continuous sedimentary records spanning tens of thousands of years (Tianyang Maar in China is hosted the longest known record spanning at least 400 kyr BP) that are ideal for the investigation of climate change on different timescales, including orbital, millennial-centennial and annual-decadal. Third, recent studies of biomarkers based on long-chain alkenones (LCAs) and glycerol dialkyl glycerol tetraethers (GDGTs) have demonstrated the potential of maar lakes for quantitative paleotemperature reconstruction. In this study, we review some of the more significant achievements of palaeoclimatic research based on maar lake sediment sequences from China, with the focus on chronology, multiple timescales and quantitative paleoclimatic reconstruction. • Varves and tephra layers existed in maar sediment can develop high-resolution chronologies combined with isotopic dating. • Maars and maar lakes provide continuous sedimentary records for the investigation of climate change. • Biomarkers (LCAs or GDGTs) from maar sediment provide the potentials for quantitative paleotemperature reconstruction. [ABSTRACT FROM AUTHOR]