Discussion of symposium on land erosion “Piping”

Abstract

The present writers are familiar only with the Picacho and San Pedro areas, among those cited by the authors, and therefore limit discussion to the occurrence of earth cracks in these areas. The existence of piping is not questioned, and the five conditions suggested by the authors are a justified explanation in the San Pedro area, for example. It is thought, however, that some of the phenomena described as piping are earth cracks whose origins are governed by factors other than those outlined. Once formed, certain earth cracks may facilitate the development of piping by providing ready access to downward and lateral movement of water.

Classification, grading criteria and quantitative expression of earth fissures: a case study in Daming Area, North China Plain

“…With further study, more and more scholars use painstaking 'lines' to describe these earth fissures. They even analysed stratigraphic profiles and found that these earth fissures appear to be dynamic and are more closely related to atmospheric precipitation and groundwater pumping activities (Heindl et al 1955;Pashley 1961;Carpenter 1993). Because these factors affect earth fissures and their characteristics emphasize different aspects, studies on these factors often lead to different judgments on the same geological phenomenon and even opposite conclusions.…”

Earth-Fissure Movements Associated with Fluctuations in Ground-Water Levels near the Picacho Mountains, South-Central Arizona, 1980-84

“…In general, however, earth fissures occur in areas of low seismicity (Holzer, 1986). In particular, the Basin and Range province in Arizona is an area of low seismicity (Sumner, 1976 Heindl and Feth (1955) argued against piping as a sole cause of fissuring because drainage of fissures is internal.…”

Earth-fissure movements associated with fluctuations in ground-water levels near the Picacho Mountains, south-central Arizona, 1980-84

“…Heindl and Feth (1955) rejected the piping hypothesis because earth fissures drain internally. Pashley (1961) Correlation of horizontal strain with water-level fluctuations was tested statistically using Pearson correlation coefficients (Sokal and Rohlf, 1969).…”