Class <<Type>> ConstituentPart

<xs:element xmlns:xs="http://www.w3.org/2001/XMLSchema" name="ConstituentPart" type="gsmlem:ConstituentPartType" substitutionGroup="gml:AbstractGML">

    <xs:annotation>

        <xs:documentation>The Constituent Part class describes how Earth Materials may be made up of other Earth Materials, including the proportion of the constituent part in the whole 

				(eg: 20%, minor, dominant); the role that the constituent plays in the whole (eg: matrix, groundmass, framework, phenocryst, xenolith, vein).

				

				The distinction between "role" and "particleType" is subtle.  An operational test is that constituentType may be determined independent of relationship 

				between particles in the aggregation, whereas role requires consideration of the relationship to other particles. A particle may be identified as clast, 

				independent of its material composition, and independent of its relationship to other grains in a rock. The term 'floating clast' is a role, because it is dependent 

				on the relationship 'not in contact with other clasts'. Consider Dunham's textural classification of carbonate rocks (wackestone, packstone, grainstone...) in the 

				description of carbonate rocks. The description is predicated on identification of two kinds of intraclasts (grains) and matrix (carbonate mud), and then uses 

				this distinction to establish relationships--mud supported vs. grain supported -- that define roles for the two types of constituents (framework, matrix...).



Examples of type vs. role:

- Particle type: clast. Role: framework, floating particle

- Particle type: crystal. Role: matrix, pseudomatrix (in case that matrix is interpreted as recrystallized material)

- Particle type: clast. Role: matrix (in case that matrix is interpreted as very-fine grained detrital fraction)

- Particle type: crystal. Role: cement (in case that material insterstitial to particles is crystalline material introduced during diagenesis)

- Particle type: crystal. Role: phenocryst (in igneous rock)

- Particle type: microlite Role: groundmass (in porphyrytic igneous rock)

- Particle type: crystal. Role: framework (in igneous rock)

- Particle type: pyroclast. role: framework (in tuff)

- Particle type: crystal Role: oikocryst

- Particle type: crystal Role: overgrowth

- Particle type: biogenic particle Role: floating particle

- Particle type: ooid Role: framework</xs:documentation>

    </xs:annotation>

</xs:element>

<xs:complexType xmlns:xs="http://www.w3.org/2001/XMLSchema" name="ConstituentPartType">

    <xs:complexContent>

        <xs:extension base="gml:AbstractGMLType">

            <xs:sequence>

                <xs:element name="proportion" nillable="true">

                    <xs:annotation>

                        <xs:documentation>The fraction of the whole that is formed by a ConstituentPart in a part/whole relationship.  Used for the ConstituentPart portion in a CompoundMaterial. 



Quantity that specifies the fraction of the Earth Material formed by the part (eg: 20%, minor, dominant)</xs:documentation>

                    </xs:annotation>

                    <xs:complexType>

                        <xs:complexContent>

                            <xs:extension base="swe:QuantityRangePropertyType">

                                <xs:attribute name="nilReason" type="gml:NilReasonType"/>

                            </xs:extension>

                        </xs:complexContent>

                    </xs:complexType>

                </xs:element>

                <xs:element name="role" type="gml:ReferenceType">

                    <xs:annotation>

                        <xs:documentation>The role a ConstituentPart plays in a CompoundMaterial aggregation. The same EarthMaterial may occur as different ConstituentParts playing different roles within the same CompoundMaterial.  For example, feldspar may be present as groundmass (a ConstituentPart::role) and as phenocrysts (an ConstituentPart::role) within a single igneous rock.</xs:documentation>

                    </xs:annotation>

                </xs:element>

                <xs:element name="material" type="gsmlem:EarthMaterialPropertyType" nillable="true"/>

                <xs:element name="particleGeometry" nillable="true">

                    <xs:complexType>

                        <xs:complexContent>

                            <xs:extension base="gsmlem:ParticleGeometryDescriptionPropertyType">

                                <xs:attribute name="nilReason" type="gml:NilReasonType"/>

                            </xs:extension>

                        </xs:complexContent>

                    </xs:complexType>

                </xs:element>

                <xs:element name="relatedMaterial" type="gsmlem:MaterialRelationPropertyType" minOccurs="1" maxOccurs="unbounded" nillable="true">

                    <xs:annotation>

                        <xs:documentation>Specifies the ConstituentPart that is playing the target role in the MaterialRelation</xs:documentation>

                    </xs:annotation>

                </xs:element>

            </xs:sequence>

        </xs:extension>

    </xs:complexContent>

</xs:complexType>

<xs:complexType xmlns:xs="http://www.w3.org/2001/XMLSchema" name="ConstituentPartPropertyType">

    <xs:sequence minOccurs="0">

        <xs:element ref="gsmlem:ConstituentPart"/>

    </xs:sequence>

    <xs:attributeGroup ref="gml:AssociationAttributeGroup"/>

    <xs:attributeGroup ref="gml:OwnershipAttributeGroup"/>

</xs:complexType>