Why would the geometry be different dependent on task? Disclosure: the source layer is in NAD27 state plane, but the published service is in WebMercator (don't ask....not my service). However, it is still odd that the two tasks return different geometries.
ID Task:
http://<ourserver>.com/arcgis/rest/services/Environmental/HBC/MapServer/identify?geometry={"x"%3A-10104270.40554004%2C"y"%3A3421909.1378388647%2C"spatialReference"%3A{"wkid"%3A102100}}&geometryType=esriGeometryPoint&sr=102100&layers=all%3A37&layerDefs=&time=&layerTimeOptions=&tolerance=4&mapExtent=-10104780.9810024%2C3421630.85928276%2C-10103634.4255781%2C3422182.6390807&imageDisplay=1920%2C924%2C96&returnGeometry=true&maxAllowableOffset=&geometryPrecision=&dynamicLayers=&returnZ=false&returnM=false&gdbVersion=&f=pjson
Result:
{
"displayFieldName": "Lease_Desc", "fieldAliases": { "Lease_Desc": "Lease_Desc" }, "geometryType": "esriGeometryPolygon", "spatialReference": { "wkid": 102100, "latestWkid": 3857 }, "fields": [ { "name": "Lease_Desc", "type": "esriFieldTypeString", "alias": "Lease_Desc", "length": 254 } ], "features": [ { "attributes": { "Lease_Desc": "Kelly-Union Prod. mineral lease except land in the limits of Kelly Uint #1 & Bourg #3" }, "geometry": { "rings": [ [ [ -10104329.693222033, 3421940.565859702 ], [ -10104085.713358521, 3421945.3538992852 ], [ -10104328.649349043, 3421868.1444641766 ], [ -10104329.693222033, 3421940.565859702 ] ] ] } } ]}
QueryTask:
http://<ourserver>com/arcgis/rest/services/Environmental/HBC/MapServer/37/query?where=FID%3D0&text=&objectIds=&time=&geometry=&geometryType=esriGeometryEnvelope&inSR=&spatialRel=esriSpatialRelIntersects&relationParam=&outFields=&returnGeometry=true&maxAllowableOffset=&geometryPrecision=&outSR=102100&returnIdsOnly=false&returnCountOnly=false&orderByFields=&groupByFieldsForStatistics=&outStatistics=&returnZ=false&returnM=false&gdbVersion=&returnDistinctValues=false&f=pjson
Result:{ "displayFieldName": "Lease_Desc", "fieldAliases": { "Lease_Desc": "Lease_Desc" }, "geometryType": "esriGeometryPolygon", "spatialReference": { "wkid": 102100, "latestWkid": 3857 }, "fields": [ { "name": "Lease_Desc", "type": "esriFieldTypeString", "alias": "Lease_Desc", "length": 254 } ], "features": [ { "attributes": { "Lease_Desc": "Kelly-Union Prod. mineral lease except land in the limits of Kelly Uint #1 & Bourg #3" }, "geometry": { "rings": [ [ [ -10104329.693222033, 3421940.565859702 ], [ -10104085.713358521, 3421945.3538992852 ], [ -10104328.649349043, 3421868.1444641766 ], [ -10104329.693222033, 3421940.565859702 ] ] ] } } ]