KNP Geomorphological Survey
INTRODUCTION

The geomorphological component of the Khirthar National Park Baseline Environmental Study was established to determine the basic geomorphology of the Park. This can be summarized as the geological surfaces and forms that make up the landscape (e.g. hillslopes, terraces, dunes), the materials that make up those surfaces and forms, the processes that create the forms, and the rates at which these processes operate.

Understanding these elements of the landscape is important for two main reasons. First, geomorphology provides a structure for describing and explaining the patterns and processes described by other facets of the study (e.g., there may be a close association between vegetation types and geomorphology). These relationships can then form the basis of land system maps. The second reason is in terms of the changes over time that are taking place in those geomorphic systems (e.g., erosion, sedimentation).

Methodology used to obtain geomorphological data of the park was determined by the size of the area being studied. We used satellite imagery and aerial photographs to prepare a preliminary geomorphological map. During six weeks of fieldwork this preliminary map was field-checked and detail was added where appropriate.

The geology of Kirthar National Park is dominated by low, rocky mountain ranges trending north-south and separated by broad flat valleys. These represent the erosional remnants of uplifted and highly deformed Tertiary and upper Mesozoic carbonate and clastic rocks. Deformation was the result of the collision between the sub-continent with the Asian plate around 45 m.y.b.p. Fossil shells, coral and other marine organisms are common and attest to large-scale uplift resulting from continental collision.

Over 20 different geomorphological units have been mapped to differentiate landscape processes in the area. The geomorphology is typical of arid and semi-arid mountain terranes. Piedmonts, perennial alluvial fans and braided river channels separate elevated areas of bedrock outcrops.

One of the striking features of Kirthar National Park is the almost complete absence of contemporary depositional features. This is probably the result of the high carbonate content of the bedrock that results in large amounts of the eroded material leaving the Park area in solution.

At the time of publishing the website, work was continuing with the aim of establishing a landscape history of the park and finalising the geomorphological map.