Complex sentence: Studies on quartz fluid inclusions suggest that this mineralisation was caused by fluid derived from Permo-Triassic sedimentary sequence that once covered the entire area and is still preserved in the Southwest Approaches to the English Channel.
Split into simpler sentences: Studies on quartz fluid inclusions suggest that this mineralisation was caused by fluid coming from Permo-Triassic sedimentary rocks sequence that once covered the entire area. These rocks still preserved in the Southwest Approaches to the English Channel.