Class <<DataType>> ParticleGeometryDescription

<xs:element xmlns:xs="http://www.w3.org/2001/XMLSchema" name="ParticleGeometryDescription" type="gsmlem:ParticleGeometryDescriptionType" substitutionGroup="gml:AbstractObject">

    <xs:annotation>

        <xs:documentation>ParticleGeometryDescription describes particles in a CompoundMaterial independent of their relationship to each other or orientation. It is distinguished from Fabric in that the ParticleGeometryDescription remains constant if the material is disaggregated into its constituent particles, whereas Fabric is lost if the material is disaggregated.  Properties include the particle size (grainsize), particle sorting (size distribution, eg: well sorted, poorly sorted, bimodal sorting), particle shape (surface rounding or crystal face development, eg: well rounded, euhedral, anhedral), and particle aspectRatio (eg: elongated, platy, bladed, compact, acicular).</xs:documentation>

    </xs:annotation>

</xs:element>

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

    <xs:sequence>

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

            <xs:annotation>

                <xs:appinfo>

                    <gml:targetElement xmlns:gml="http://www.opengis.net/gml/3.2">gsmlem:ParticleTypeTermType</gml:targetElement>

                </xs:appinfo>

                <xs:documentation>Terms to specify the nature of individual particles of each constituent in an Earth Material aggregation, based mostly on their genesis.  If applied on ParticleDescription for CompoundMaterial, then would characterize all particles in aggregate. Use this property on CompoundMaterial to distinguish rocks composed of crystals (crystalline rocks) from rocks composed of granular particles (clasts, fragments). Examples include oolith, crystals, pore space. Constituent type is determined based on the nature of the particles, and ideally is independent of the relationship between particles in a compound material aggregation.  See discussion of particleType vs ConstituentPart.role in the scope notes for ConstituentPart.</xs:documentation>

            </xs:annotation>

        </xs:element>

        <xs:element name="aspectRatio" nillable="true" minOccurs="1" maxOccurs="unbounded">

            <xs:annotation>

                <xs:documentation>AspectRatio describes the geometry of particles based on the ratios of lengths of long, intermediate and short axes of grains. Equates to sphericity in sedimentary rocks (ie: the degree to which the shape of a particle approximates a sphere).  A quantitative specification based on the ratio of lengths of long, intermediate and short axes of grain shape (Sneed and Folk, 1958; Zingg, 1935). (eg: prolate, slightly flattened, very bladed, equant, acicular, tabular)</xs:documentation>

            </xs:annotation>

            <xs:complexType>

                <xs:complexContent>

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

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

                    </xs:extension>

                </xs:complexContent>

            </xs:complexType>

        </xs:element>

        <xs:element name="shape" nillable="true" minOccurs="1" maxOccurs="unbounded">

            <xs:annotation>

                <xs:documentation>The Shape attribute describes, a) the development of crystal faces bounding particles in crystalline compond materials, and b) surface rounding of grains in sedimentary rocks. Roundness is a measure of the sharpness of the edges between surfaces bounding a particle (see Jackson, 1997; Wadell, 1932). Terms should be appropriate for the kind of compound material (eg: for crystalline rocks- euhedral, ideoblastic, subhedral, anhedral, xenoblastic; for sedimentary rocks - angular, rounded)</xs:documentation>

            </xs:annotation>

            <xs:complexType>

                <xs:complexContent>

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

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

                    </xs:extension>

                </xs:complexContent>

            </xs:complexType>

        </xs:element>

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

            <xs:annotation>

                <xs:documentation>The Size attribute specifies particle grainsize.  Values may be reported using absolute measurements (eg: range, mean, median, mode, maximum) or as descriptive terms from a schema appropriate to the type of Compound Material (eg: the Udden-Wentworth sheme for clastic sedimentary rocks - silt, sand, gravel; volcaniclastic rocks - ash, lapilli, bomb; crystalline rocks - fine, medium, coarse, cryptocrystalline)</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="sorting" nillable="true" minOccurs="1" maxOccurs="unbounded">

            <xs:annotation>

                <xs:documentation>The Sorting attribute holds text terms to specify size distribution of particles in a CompoundMaterial. Terminology for sorting in sedimentary rocks is based on the quantitative Graphic Standard Deviation (IGSD) scheme proposed by Folk (1968, 1974).  Example terms for this attribute may include sedimentary terms such as well sorted and poorly sorted, or igneous terms such as porphyritic, equigranuilar, seriate.</xs:documentation>

            </xs:annotation>

            <xs:complexType>

                <xs:complexContent>

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

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

                    </xs:extension>

                </xs:complexContent>

            </xs:complexType>

        </xs:element>

        <xs:element name="sourceOrganism" type="gml:ReferenceType " minOccurs="1" maxOccurs="unbounded" nillable="true">

            <xs:annotation>

                <xs:documentation>A byReference link to a description of an organism that was the source of the fossil particle within a compound material.  This association may only be populated if particleType = "fossil".</xs:documentation>

            </xs:annotation>

        </xs:element>

    </xs:sequence>

</xs:complexType>

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

    <xs:sequence>

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

    </xs:sequence>

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

</xs:complexType>