Lead Mineralisation Within The Stublick Fault System At Church Burn And Wolf Hills, Haltwhistle, Northumberland

Abstract

Two hitherto unreported small clusters of lead-bearing veins and associated workings at Church Burn and Wolf Hills, south of Haltwhistle, described here, add to the group of mineral deposits within the main Tyne Valley, sometimes collectively referred to as the Haydon Bridge Orefield. Long regarded as an outlying portion of the Northern Pennine Orefield, with which they share close structural and mineralogical similarities, these deposits are separated by approximately 15 km of barren ground from the nearest mineralisation in the orefield and lie adjacent to the Stublick Fault, part of the Maryport-Gilcrux-Stublick-Ninety Fathom Fault System. This major fault belt acted as a syn-sedimentary ‘hinge zone’ during Carboniferous times resulting in the accumulation of substantially greater thicknesses of Carboniferous sediments in the Northumberland-Solway Basin than on the Alston and Lake District blocks to the south. Similar base metal-barium mineralisation is common within a narrow belt along this structural line from coast to coast. It is suggested that the Church Burn and Wolf Hills mineralisation adds further weight to the hypothesis that this belt of mineralisation is both structurally and genetically related to the development of this major Carboniferous fault line. Also reported here is the first reliable record of plumbojarosite from a Pennine location.