Geology
Big Timber Creek lies wholly within the Atlantic Coastal Plain Physiographic Province, specifically that portion known as the Inner Coastal Plain. The coastal plain is a wedge-shaped mass of sediments, mostly unconsolidated, lying upon Precambrian basement rock. It extends from the fall line out onto the continental shelf, thickening as it goes at the rate of 80 to 100 feet per mile (15–19 m/km).
New Jersey's inner coastal plain is defined by a cuesta that runs through the coastal plain roughly northeast to southwest across the middle and southern parts of the state. This cuesta marks the transition between the underlying Cretaceous sediments toward the Piedmont and the more recent Miocene sediments seaward and is itself Cretaceous in origin. In its southern reaches, where Big Timber Creek lies, it runs roughly parallel to the Delaware River at a distance of about 20 miles (32 km) and delineates the left edge of the Delaware River watershed in southern New Jersey.
The surficial geology of the New Jersey inner coastal plain is among the most complex in the world. At least eight of the 14 or 15 sedimentary strata, or formations, laid down since the Cretaceous period appear at the surface in the Big Timber Creek basin. Each formation is itself made up of many layers, some the result of irregular interglacial stream deposition. The situation is further complicated by the appearance of fragments of older formations at a shallower level than more recent ones, owing to cycles of deposition and erosion; in fact, the so-called Bridgeton formation, the oldest, containing iron-indurated sand, forms the summits of the few prominences on the landscape. Generally speaking, the surface of the area is weathered Cretaceous coastal plain consisting of quartz sand, with patches where gravel or clay are found. Glauconite occurs in varying concentrations in the younger formations, and some bog iron is seen. There is no rock, though some iron-bearing sand has become concreted and rock-like.
Read more about this topic: Big Timber Creek, Description, The Land