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The seismic merging dataset, wireline logs, core photographs, thin sections, and other geological information were employed to investigate sequence architecture and reveal depositional evolution of Enping Formation in Lufeng Depression, Pearl River Mouth Basin. The results showed that one second‐order sequence and four third‐order sequences were identified based on the unconformities along basin margin/slope and correlative conformities in the basin centre. In addition, several associated sedimentary facies or microfacies (including braided channel deposits, subaqueous distributary channel deposits, beach‐bar deposits, and so on) that were recognized within sequence stratigraphic framework and depositional evolution were revealed by well tie–seismic correlations with seismic attributes extracted from the stratal slicing in terms of sand sections/units in Enping Formation. It was characterized by progradational process from seismic attributes in general that the delta deposits gradually retrograded. Through comprehensive analysis, it can be concluded that episodic tectonic movements and subsequent uplift played an important role in controlling sequence architecture. Sediment supply and lacustrine level fluctuations derived from accommodation space changes exerted an essential effect on depositional evolution. This study provides new and robust insights into understanding the sequence architecture, depositional evolution, and hydrocarbon exploration in Enping Formation. In addition to the significance for academia, study of sequence architecture and depositional evolution are of great importance for hosting potential hydrocarbon reserves, because they are frequently related to important and potential reservoirs. Consequently, investigating sequence architecture and depositional evolution are significant economically as well.

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Abstract. New particle formation (NPF) events and their impacts on cloud condensation nuclei (CCN) were investigated using continuous measurements collected in urban Shanghai from 1 to 30 April 2012. During the campaign, NPF occurred in 8 out of the 30 days and enhanced CCN number concentration (N CCN ) by a factor of 1.2-1.8, depending on supersaturation (SS). The NPF event on 3 April 2012 was chosen as an example to investigate the NPF influence on CCN activity. In this NPF event, secondary aerosols were produced continuously and increased PM 2.5 mass concentration at a rate of 4.33 µg cm −3 h −1 , and the growth rate (GR) and formation rate (FR) were on average 5 nm h −1 and 0.36 cm −3 s −1 , respectively. The newly formed particles grew quickly from nucleation mode (10-20 nm) into CCN size range. N CCN increased rapidly at SS of 0.4-1.0 % but weakly at SS of 0.2 %. Correspondingly, aerosol CCN activities (fractions of activated aerosol particles in total aerosols, N CCN /N CN ) were significantly enhanced from 0.24-0.60 to 0.30-0.91 at SS of 0.2-1.0 % due to the NPF. On the basis of the κ-Köhler theory, aerosol size distributions and chemical composition measured simultaneously were used to predict N CCN . There was a good agreement between the predicted and measured N CCN (R 2 = 0.96, N predicted /N measured = 1.04). This study reveals that NPF exerts large impacts on aerosol particle abundance and size spectra; thus, it significantly promotes N CCN and aerosol CCN activity in this urban environment. The GR of NPF is the key factor controlling the newly formed particles to become CCN at all SS levels, whereas the FR is an effective factor only under high SS (e.g., 1.0 %) conditions.

Abstract. Measurements of cloud condensation nuclei (CCN), condensation nuclei (CN) and aerosol chemical composition were performed simultaneously at an urban site in Shanghai from 6 to 9 November 2010. The variations of CCN number concentration (N CCN ) and aerosol activity (activated aerosol fraction, N CCN /N CN ) were examined during a fog-haze co-occurring event. Anthropogenic pollutants emitted from vehicles and unfavorable meteorological conditions such as low planetary boundary layer (PBL) height exerted a great influence on PM 2.5 and black carbon (BC) loadings. N CCN at 0.2 % supersaturation (SS) mostly fell in the range of 994 to 6268 cm −3 , and the corresponding N CCN /N CN varied between 0.09 and 0.57. N CCN and N CCN /N CN usually were usually higher in the hazy case due to increased aerosol concentration in the accumulation mode (100-500 nm), and lower in the foggy-hazy and clear cases. The BC mass concentration posed a strong positive effect on N CCN in the foggy-hazy and hazy cases, whereas it poorly correlated with N CCN in the clear case. N CCN /N CN was weakly related with BC in both foggy-hazy and hazy cases. By using a simplified particle hygroscopicity (κ), the calculated critical dry size (CDS) of activated aerosol did not exceed 130 nm at 0.2 % SS in spite of diverse aerosol chemical compositions. The predicted N CCN at 0.2 % SS was very successful compared with the observed N CCN in clear case (R 2 = 0.96) and foggy-hazy/hazy cases (R 2 = 0.91). In addition, their corresponding ratios of predicted to observed N CCN were on average 0.95 and 0.92, respectively. More organic matter is possibly responsible for this closure difference between foggy-hazy/hazy and clear cases. These results reveal that the particulate pollutant burden exerts a significant impact on N CCN , especially N CCN /N CN promotes effectively during the polluted periods.

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