OBJECTIVES: TO PRODUCE CRUSTAL MAGNETIC FIELD MAPS OF MERCURY COVERING LATITUDES OF ABOUT 35N TO 80N AND APPLY THEM TO: (A) EVALUATE WHETHER PREVIOUS EVIDENCE [1 2] FOR CONCENTRATIONS OF ANOMALIES NEAR IMPACT BASINS IN THE HEMISPHERE CENTERED AT 180E LONGITUDE (E.G. CALORIS) EXTENDS ALSO TO OTHER BASINS IN THE OPPOSITE HEMISPHERE; (B) MODEL SELECTED MAGNETIC ANOMALIES TO ESTIMATE PALEOMAGNETIC POLE POSITIONS; AND (C) MAKE USE OF CORRELATIONS BETWEEN CRUSTAL MAGNETIC ANOMALIES AND SURFACE SPECTRAL PROPERTIES TO PRODUCE AN APPROXIMATE MAP OF THE EXPECTED GLOBAL DISTRIBUTION OF CRUSTAL MAGNETIC FIELDS ON MERCURY. METHODS/TECHNIQUES: IN YEAR 1 WORK WILL FOCUS FIRST ON PRODUCING A REFINED MAP OF THE THREE VECTOR COMPONENTS AND SCALAR MAGNITUDE OF THE HERMEAN CRUSTAL FIELD AT A CONSTANT ALTITUDE OF 40 KM COVERING ALL LONGITUDES AT NORTHERN MIDDLE TO HIGH LATITUDES. PREVIOUS MAPPING OF THE CRUSTAL FIELD [1 2] WILL BE REFINED BY USING AN INTERNAL CORE FIELD MODEL [3 4] TO BETTER ISOLATE THE CRUSTAL FIELD AND BY USING THE EQUIVALENT SOURCE DIPOLE (ESD) TECHNIQUE MODIFYING INPUT PARAMETERS TO PROVIDE AN EQUALLY SPACED DIPOLE DISTRIBUTION. THEN THE EXTENDED FIELD MAP WILL BE USED TO EVALUATE WHETHER MAGNETIC ANOMALIES ARE CONCENTRATED NEAR AND WITHIN OTHER IMPACT BASINS BESIDES CALORIS AND SOBKOU [2] OR IF SOME BASINS DO NOT HAVE SUCH CONCENTRATIONS. IN YEAR 2 SELECTED ANOMALY GROUPS WILL BE MODELED USING PARKER'S METHOD [5 6] TO ESTIMATE PALEOMAGNETIC POLE POSITIONS WITH IMPLICATIONS FOR TRUE POLAR WANDER DURING MERCURY'S EARLY HISTORY. IN YEAR 3 A MULTIPLE LINEAR REGRESSION (MLR) ANALYSIS WILL BE CONDUCTED OF CRUSTAL FIELD MAGNITUDE VERSUS THE MESSENGER DUAL IMAGING SYSTEM (MDIS) 3-COLOR BASEMAP TO QUANTIFY THE RELATIONSHIP BETWEEN CRUSTAL FIELD STRENGTH AND SURFACE SPECTRAL PROPERTIES. THE MLR RESULTS WILL THEN BE APPLIED TOGETHER WITH GLOBAL MDIS DATA TO PRODUCE AN APPROXIMATE GLOBAL MAP OF THE EXPECTED CRUSTAL FIELD DISTRIBUTION. SIGNIFICANCE/RELEVANCE: THE PROPOSED WORK FALLS WITHIN THE SCOPE OF THE DISCOVERY DATA ANALYSIS PROGRAM BECAUSE IT WILL ENHANCE THE SCIENTIFIC RETURN FROM THE HIGHLY SUCCESSFUL MESSENGER MISSION. IT WILL PRODUCE OPTIMALLY ACCURATE LOW-ALTITUDE VECTOR CRUSTAL MAGNETIC FIELD MAPS AT NORTHERN MIDLATITUDES AND AN APPROXIMATE GLOBAL MAP OF PROJECTED CRUSTAL FIELD STRENGTH THAT CAN BE USED BY THE PLANETARY SCIENCE COMMUNITY FOR OTHER PURPOSES. IF SOME OF MERCURY'S BASINS ARE FOUND NOT TO HAVE CONCENTRATIONS OF MAGNETIC ANOMALIES THIS COULD IMPLY A ROLE OF IMPACTOR COMPOSITION (E.G. IRON CONTENT) IN PRODUCING THE CRUSTAL MATERIALS THAT ARE STRONGLY MAGNETIZED [7]. THE PALEOMAGNETIC POLE POSITIONS WILL ALLOW AN EVALUATION OF WHETHER TRUE POLAR WANDER OCCURRED ON MERCURY DURING ITS EARLY HISTORY. THE GLOBAL MAP OF THE EXPECTED CRUSTAL FIELD DISTRIBUTION WILL PROVIDE A PREDICTION TO BE TESTED WITH FUTURE DATA FROM THE EUROPEAN AND JAPANESE BEPICOLOMBO MISSION. IT WILL ALSO PROVIDE A MEANS OF INVESTIGATING THE LIKELIHOOD THAT OTHER BASINS ON MERCURY HAVE CRUSTAL FIELDS CONCENTRATED NEAR THEM.