This theme contains information about Solution Subsidence Structures (Q -Quaternary and M -Miocene).

Qs - Modern beach sands (HOLOCENE).Qv - Valley fill (LATE PLEISTOCENE-HOLOCENE, TYRRHENIAN): Low angle subaerial fanglomerate cones, terra rossas, local clays and alluvium. Fanglomerates frequently are dominated by subangular carbonate lithoclast breccias and interpenetrative channels. Intercalated terra rossa palaeosols often contain rhizoid (root) fabrics and nodular caliche of varying ages but all post date valley cutting.Thickness 0-7m. Qb - Dunes and raised beach deposits (LATE PLEISTOCENE-HOLOCENE, TYRRHENIAN): Wind blown foraminiferal, marine mollusc and quartzarenitic grainstones. In Malta, the Marfa Point deposit contains rhizoid fabrics, and pulmonate gastropods of undiagnostic age. Terra rossa palaeosols are intercalated in some sections. The main deposits in Gozo are at Ramla Bay. Thickness 0-3m. Qt - Tufa and travertine deposits (? EARLY PLEISTOCENE): Friable, cream coloured lime mudstones, and wackestones with abundant plant remains, pulmonate and hydrobid gastropods. All deposits developed before termination of valley incision. The Fiddien Valley deposit near Rabat (Malta) pre-dates the terra rossa palaeosols but molluscan faunas are undiagnostic of age. Thickness 0-16m.

The Tertiary theme gives information on the Miocene and Oligocene bedrock divided at Member level.It was produced from the Geological Map of the Maltese Islands published at a scale of 1:25,000 by the Oil Exploration Directorate (OPM) in 1993. This map depicts the bedrock geology of the Maltese Islands including lithological and structural information.

The Stratigraphical boundaries are indicated by solid lines where observed and by dashed lines where inferred.

The Fault theme contains information on faults and fault controlled synclines divided into threeclasses as follows:Fault Obs - Observed faults are indicated by solid lines. Downthrow direction indicated by bars and sense of relative movement indicated by arrows;Fault Inf - Inferred faults are indicated by dashed lines. Downthrow direction indicated by bars and sense of relative movement indicated by arrows;Fold Syncline - Fault controlled syncline axial trace.