North China Plain around 1000 BC.
Own work, using

Modern coastline, lakes and rivers from Natural Earth 1:10m Physical Vectors.
Contours derived from 2-Minute Gridded Global Relief Data (ETOPO2) v2, NOAA National Centers for Environmental Information, using gdal_contour (from GDAL).
Ancient coastline, lakes and rivers based on:
Tan Qixiang (1996 [1982]), The Historical Atlas of China, volume 1, China Cartographic Publishing House, ISBN 7-5031-1840-7, pp15–18.
Liu Li and Chen Xingcan (2012), The Archaeology of China: From the Late Paleolithic to the Early Bronze Age, Cambridge University Press, ISBN 978-0-521-64310-8, Figures 8.13 (p289), 10.1 (p351), 10.8 (p365).
Conversion to SVG using svgis.
Kanguole