Field Mapping Module 02

Quaternary Geology of Lower San Antonio Canyon

(Course  Number GSC 499-02, CRN 44733 in the Fall, 2000 Catalog)   

Instructor: J. A. Nourse              

General Assignment: Map the Quaternary sedimentary deposits in lower San Antonio Canyon, delineate damage to the old Mt. Baldy Road caused by the 1969 flood, and write a summary report on the Quaternary geologic history of the canyon.  This report must include the illustrations and supporting data described below.

Logistics:  Begin mapping with your instructor on June 26, 2000.  Students will map contacts between crystalline bedrock and Quaternary deposits, and contacts separating various Quaternary units.  Most field mapping will be carried out on 8½ ” x 11” fragments of a 1:6,000 topographic base.  Field data is to be compiled onto a 1:12,000 office map that covers the entire field area.  A total of six days field work is required.  Students are encouraged to transfer their data to the office map following each day in the field.  In this fashion, a working model of the entire field area will evolve as the summer’s work progresses.

Work to be Submitted: 

(1) One finalized 1:12,000 geologic map, neatly inked and lightly colored, with a detailed explanation.  This map should clearly delineate the following lithologic units: Holocene alluvium, talus deposits, Pleistocene stream terraces, Pleistocene or Holocene(?) landslides, and crystalline bedrock.  The map should also differentiate remnant (existing) segments of the old Mt. Baldy Road from sections washed out during the 1969 flood. Maximum aerial coverage will be San Antonio Canyon between the latitudes of San Antonio Dam and Ontario Power Plant #2;

(2) Three cross sections (locations to be specified by instructor) showing details of the Quaternary deposits relative to bedrock;

(3) A concise, written report consisting of: (a) an introductory statement summarizing the purpose and objectives of the field work, (b) complete description of major lithologic units, (c) a generalized stratigraphic column (or columns) showing representative sedimentologic features observed in the Pleistocene stream terrace deposits, and (d) a comprehensive Quaternary geologic history of the study area based upon your field work and literature search;

(4) A detailed notebook containing a daily diary of your field activities which should include: (a) notations of times of arrival and departure from the field each day, and (b) specific description of each field site and the data collected, and (c) a referencing system that ties your field notes to specific locations on the field maps;

(5) Your original field maps.

**All work is due September 15, 2000**