Lateral intrusion processes in the ocean can facilitate mixing and modification among water masses with different properties. Lateral intrusion also exist in the deep and bottom layers around the Antarctic margin, promoting the offshore export of Antarctic Bottom Water (AABW) and the onshore intrusion of Lower Circumpolar Deep Water (LCDW). Based on hydrographic observations along 110°E during austral summers from 2011 to 2020, this study applied the Turner angle (Tu) threshold method to identify lateral intrusion layers in the LCDW and AABW layers. The intrusion strength is quantified by the deviation of observed temperature-salinity profiles from corresponding linearly interpolated values, with larger values indicating stronger nonlinearity and more pronounced intrusion signals. The results show that numerous cold and fresh lateral intrusion structures are present in both the LCDW and AABW layers, with thicknesses generally within 100 m, indicating offshore export of locally formed AABW variety. The peak intrusion strength of LCDW occurred in 2015, and the maximum values for both strength and thickness were concentrated between 2013 and 2016. For AABW, the peak intrusion strength appeared in 2016, while the maximum thickness occurred in 2013. Notably, the number of intrusion layers for both LCDW and AABW decreased markedly or even disappeared in 2019 and 2020. These sub-bottom lateral intrusions contribute to enhanced ventilation within their respective layers. This study provides valuable insight into the drivers of AABW property changes and the offshore export of newly formed bottom water.

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